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SCHEDULE III REAL ESTATE AND ACCUMULATED DEPRECIATION (Details) $ in Thousands | 12 Months Ended |  |
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Dec. 31, 2016 USD ($) apartment | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2016 USD ($) ft² | Dec. 31, 2014 USD ($)
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Encumbrance |  |  |  | $ 2,191,481 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,501,616 |
Buildings and improvements |  |  |  | 8,663,818 |
Costs capitalized subsequent to acquisition |  |  |  | 1,510,872 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,559,743 |
Buildings and improvements |  |  |  | 10,116,563 |
Total | $ 12,676,306 |  |  | 12,676,306 |
Accumulated depreciation | (1,949,892) | $ (1,564,806) | $ (1,254,886) | (2,311,546) | $ (1,564,806)
Aggregate cost for federal income tax purpose | 10,000,000 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Acquisition, development, and improvement of real estate | 609,669 | 1,333,102 | 5,833,617 |  |
Disposition of real estate | (264,832) | (246,314) | (32,693) |  |
Balance at the end of year | 12,676,306 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at beginning of year | (1,949,892) | (1,564,806) | (1,254,886) |  |
Balance at beginning of year | 432,165 | 402,687 | 320,921 |  |
Depreciation expense - Disposals and other | (70,511) | (17,601) | (11,001) |  |
Balance at the end of year | $ (2,311,546) | (1,949,892) | (1,564,806) |  |
BRE Properties, Inc. [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Rental property expense |  |  |  |  | 5,200,000
Encumbered Apartment Communities [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 16,620 |  |  |  |
Encumbrance |  |  |  | 2,191,481 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 794,369 |
Buildings and improvements |  |  |  | 2,564,810 |
Costs capitalized subsequent to acquisition |  |  |  | 529,149 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 807,080 |
Buildings and improvements |  |  |  | 3,081,248 |
Total | $ 3,888,328 |  |  | 3,888,328 |
Accumulated depreciation | (848,327) |  |  | (848,327) |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | 3,888,328 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (848,327) |  |  |  |
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 446 |  |  |  |
Encumbrance |  |  |  | 43,687 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,536 |
Buildings and improvements |  |  |  | 24,522 |
Costs capitalized subsequent to acquisition |  |  |  | 20,008 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,601 |
Buildings and improvements |  |  |  | 44,465 |
Total | $ 55,066 |  |  | 55,066 |
Accumulated depreciation | $ (28,536) |  |  | (28,536) |
Date of construction | 1970 |  |  |  |
Date acquired | Jan-99 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 55,066 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (28,536) |  |  |  |
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Avondale at Warner Center [Member] | Woodland Hills, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 462 |  |  |  |
Encumbrance |  |  |  | 51,531 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 12,105 |
Buildings and improvements |  |  |  | 18,252 |
Costs capitalized subsequent to acquisition |  |  |  | 33,311 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 12,682 |
Buildings and improvements |  |  |  | 50,986 |
Total | $ 63,668 |  |  | 63,668 |
Accumulated depreciation | $ (30,311) |  |  | (30,311) |
Date of construction | 1988 |  |  |  |
Date acquired | Jan-95 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 63,668 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (30,311) |  |  |  |
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Bel Air [Member] | San Ramon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 296 |  |  |  |
Encumbrance |  |  |  | 52,238 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,725 |
Buildings and improvements |  |  |  | 92,091 |
Costs capitalized subsequent to acquisition |  |  |  | 487 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 21,725 |
Buildings and improvements |  |  |  | 92,578 |
Total | $ 114,303 |  |  | 114,303 |
Accumulated depreciation | $ (9,268) |  |  | (9,268) |
Date of construction | 2009 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 114,303 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,268) |  |  |  |
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Belcarra [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 248 |  |  |  |
Encumbrance |  |  |  | 39,597 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 16,197 |
Buildings and improvements |  |  |  | 67,207 |
Costs capitalized subsequent to acquisition |  |  |  | 3,240 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 16,197 |
Buildings and improvements |  |  |  | 70,447 |
Total | $ 86,644 |  |  | 86,644 |
Accumulated depreciation | $ (7,170) |  |  | (7,170) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 86,644 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,170) |  |  |  |
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | BellCentre [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 275 |  |  |  |
Encumbrance |  |  |  | 29,629 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 8,100 |
Buildings and improvements |  |  |  | 66,666 |
Costs capitalized subsequent to acquisition |  |  |  | 5,704 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,267 |
Buildings and improvements |  |  |  | 72,203 |
Total | $ 80,470 |  |  | 80,470 |
Accumulated depreciation | $ (23,456) |  |  | (23,456) |
Date of construction | 2009 |  |  |  |
Date acquired | Mar-09 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 80,470 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (23,456) |  |  |  |
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Belmont Station [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 170 |  |  |  |
Encumbrance |  |  |  | 18,536 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,301 |
Buildings and improvements |  |  |  | 16,310 |
Costs capitalized subsequent to acquisition |  |  |  | 23,979 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,328 |
Buildings and improvements |  |  |  | 37,262 |
Total | $ 47,590 |  |  | 47,590 |
Accumulated depreciation | $ (18,245) |  |  | (18,245) |
Date of construction | 1973 |  |  |  |
Date acquired | Jun-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 47,590 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (18,245) |  |  |  |
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Brookside Oaks [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 250 |  |  |  |
Encumbrance |  |  |  | 27,059 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,088 |
Buildings and improvements |  |  |  | 44,473 |
Costs capitalized subsequent to acquisition |  |  |  | 2,845 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,088 |
Buildings and improvements |  |  |  | 47,318 |
Total | $ 66,406 |  |  | 66,406 |
Accumulated depreciation | $ (15,836) |  |  | (15,836) |
Date of construction | 2005 |  |  |  |
Date acquired | May-07 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 66,406 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,836) |  |  |  |
Encumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Canyon Oaks [Member] | San Ramon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 348 |  |  |  |
Encumbrance |  |  |  | 63,142 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 26,842 |
Buildings and improvements |  |  |  | 107,368 |
Costs capitalized subsequent to acquisition |  |  |  | 3,952 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 26,842 |
Buildings and improvements |  |  |  | 111,320 |
Total | $ 138,162 |  |  | 138,162 |
Accumulated depreciation | $ (11,480) |  |  | (11,480) |
Date of construction | 2000 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 138,162 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,480) |  |  |  |
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Carmel Creek [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 572 |  |  |  |
Encumbrance |  |  |  | 61,761 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,883 |
Buildings and improvements |  |  |  | 37,670 |
Costs capitalized subsequent to acquisition |  |  |  | 24,081 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,350 |
Buildings and improvements |  |  |  | 61,284 |
Total | $ 71,634 |  |  | 71,634 |
Accumulated depreciation | $ (41,530) |  |  | (41,530) |
Date of construction | 1975 |  |  |  |
Date acquired | Mar-98 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 71,634 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (41,530) |  |  |  |
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | City View [Member] | Hayward, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 110 |  |  |  |
Encumbrance |  |  |  | 15,133 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,465 |
Buildings and improvements |  |  |  | 21,405 |
Costs capitalized subsequent to acquisition |  |  |  | 3,467 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,465 |
Buildings and improvements |  |  |  | 24,872 |
Total | $ 32,337 |  |  | 32,337 |
Accumulated depreciation | $ (5,651) |  |  | (5,651) |
Date of construction | 2000 |  |  |  |
Date acquired | Oct-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 32,337 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,651) |  |  |  |
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Courtyard off Main [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 92 |  |  |  |
Encumbrance |  |  |  | 14,597 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,059 |
Buildings and improvements |  |  |  | 27,177 |
Costs capitalized subsequent to acquisition |  |  |  | 830 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,059 |
Buildings and improvements |  |  |  | 28,007 |
Total | $ 37,066 |  |  | 37,066 |
Accumulated depreciation | $ (4,152) |  |  | (4,152) |
Date of construction | 2009 |  |  |  |
Date acquired | Sep-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 37,066 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,152) |  |  |  |
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Domaine [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 158 |  |  |  |
Encumbrance |  |  |  | 10,697 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,758 |
Buildings and improvements |  |  |  | 14,285 |
Costs capitalized subsequent to acquisition |  |  |  | 5,961 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,757 |
Buildings and improvements |  |  |  | 20,247 |
Total | $ 25,004 |  |  | 25,004 |
Accumulated depreciation | $ (6,425) |  |  | (6,425) |
Date of construction | 1986 |  |  |  |
Date acquired | Jun-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 25,004 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,425) |  |  |  |
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Elevation [Member] | Redmond, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 220 |  |  |  |
Encumbrance |  |  |  | 21,497 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,066 |
Buildings and improvements |  |  |  | 45,249 |
Costs capitalized subsequent to acquisition |  |  |  | 2,170 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,066 |
Buildings and improvements |  |  |  | 47,419 |
Total | $ 62,485 |  |  | 62,485 |
Accumulated depreciation | $ (3,879) |  |  | (3,879) |
Date of construction | 1994 |  |  |  |
Date acquired | Jul-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 62,485 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,879) |  |  |  |
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Ellington [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 164 |  |  |  |
Encumbrance |  |  |  | 15,761 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,626 |
Buildings and improvements |  |  |  | 10,485 |
Costs capitalized subsequent to acquisition |  |  |  | 6,622 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,957 |
Buildings and improvements |  |  |  | 16,776 |
Total | $ 19,733 |  |  | 19,733 |
Accumulated depreciation | $ (8,593) |  |  | (8,593) |
Date of construction | 1970 |  |  |  |
Date acquired | Nov-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 19,733 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,593) |  |  |  |
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Fairhaven Apartments [Member] | Santa Ana, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 242 |  |  |  |
Encumbrance |  |  |  | 47,442 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 24,510 |
Buildings and improvements |  |  |  | 72,221 |
Costs capitalized subsequent to acquisition |  |  |  | 4,513 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 25,540 |
Buildings and improvements |  |  |  | 75,704 |
Total | $ 101,244 |  |  | 101,244 |
Accumulated depreciation | $ (2,120) |  |  | (2,120) |
Date of construction | 2014 |  |  |  |
Date acquired | Mar-16 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 101,244 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,120) |  |  |  |
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Form 15 [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 490 |  |  |  |
Encumbrance |  |  |  | 97,220 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 61,714 |
Buildings and improvements |  |  |  | 144,000 |
Costs capitalized subsequent to acquisition |  |  |  | 7,016 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 61,714 |
Buildings and improvements |  |  |  | 151,016 |
Total | $ 212,730 |  |  | 212,730 |
Accumulated depreciation | $ (15,886) |  |  | (15,886) |
Date of construction | 1987 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 212,730 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,886) |  |  |  |
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Foster's Landing [Member] | Foster City, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 226 |  |  |  |
Encumbrance |  |  |  | 32,118 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 26,046 |
Buildings and improvements |  |  |  | 60,773 |
Costs capitalized subsequent to acquisition |  |  |  | 3,229 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 26,046 |
Buildings and improvements |  |  |  | 64,002 |
Total | $ 90,048 |  |  | 90,048 |
Accumulated depreciation | $ (6,363) |  |  | (6,363) |
Date of construction | 1990 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 90,048 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,363) |  |  |  |
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Fountain At Riveroaks [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 705 |  |  |  |
Encumbrance |  |  |  | 82,435 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 25,073 |
Buildings and improvements |  |  |  | 94,980 |
Costs capitalized subsequent to acquisition |  |  |  | 30,967 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 25,203 |
Buildings and improvements |  |  |  | 125,817 |
Total | $ 151,020 |  |  | 151,020 |
Accumulated depreciation | $ (59,294) |  |  | (59,294) |
Date of construction | 2002 |  |  |  |
Date acquired | Feb-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 151,020 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (59,294) |  |  |  |
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Fountain Park [Member] | Playa Vista, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 215 |  |  |  |
Encumbrance |  |  |  | 19,833 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,695 |
Buildings and improvements |  |  |  | 16,753 |
Costs capitalized subsequent to acquisition |  |  |  | 19,093 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,733 |
Buildings and improvements |  |  |  | 35,808 |
Total | $ 42,541 |  |  | 42,541 |
Accumulated depreciation | $ (15,684) |  |  | (15,684) |
Date of construction | 1970 |  |  |  |
Date acquired | Jun-99 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 42,541 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,684) |  |  |  |
Encumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Hampton Place Hampton Court [Member] | Glendale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 324 |  |  |  |
Encumbrance |  |  |  | 29,295 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 14,174 |
Buildings and improvements |  |  |  | 34,065 |
Costs capitalized subsequent to acquisition |  |  |  | 3,373 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,674 |
Buildings and improvements |  |  |  | 41,938 |
Total | $ 51,612 |  |  | 51,612 |
Accumulated depreciation | $ (17,484) |  |  | (17,484) |
Date of construction | 2004 |  |  |  |
Date acquired | Dec-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 51,612 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (17,484) |  |  |  |
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Hidden Valley [Member] | Simi Valley, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 333 |  |  |  |
Encumbrance |  |  |  | 30,901 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 16,271 |
Buildings and improvements |  |  |  | 48,932 |
Costs capitalized subsequent to acquisition |  |  |  | 9,533 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 16,271 |
Buildings and improvements |  |  |  | 58,465 |
Total | $ 74,736 |  |  | 74,736 |
Accumulated depreciation | $ (18,290) |  |  | (18,290) |
Date of construction | 2000 |  |  |  |
Date acquired | Aug-08 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 74,736 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (18,290) |  |  |  |
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Highlands at Wynhaven [Member] | Issaquah, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 255 |  |  |  |
Encumbrance |  |  |  | 69,202 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,419 |
Buildings and improvements |  |  |  | 18,347 |
Costs capitalized subsequent to acquisition |  |  |  | 29,991 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,073 |
Buildings and improvements |  |  |  | 47,684 |
Total | $ 53,757 |  |  | 53,757 |
Accumulated depreciation | $ (30,084) |  |  | (30,084) |
Date of construction | 1972 |  |  |  |
Date acquired | May-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 53,757 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (30,084) |  |  |  |
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Highridge [Member] | Rancho Palos Verdes, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 608 |  |  |  |
Encumbrance |  |  |  | 64,211 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,318 |
Buildings and improvements |  |  |  | 40,601 |
Costs capitalized subsequent to acquisition |  |  |  | 18,880 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,755 |
Buildings and improvements |  |  |  | 59,044 |
Total | $ 74,799 |  |  | 74,799 |
Accumulated depreciation | $ (34,815) |  |  | (34,815) |
Date of construction | 1973 |  |  |  |
Date acquired | Mar-98 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 74,799 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (34,815) |  |  |  |
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Hillcrest Park [Member] | Newbury Park, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 342 |  |  |  |
Encumbrance |  |  |  | 35,943 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,306 |
Buildings and improvements |  |  |  | 22,720 |
Costs capitalized subsequent to acquisition |  |  |  | 18,651 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,315 |
Buildings and improvements |  |  |  | 41,362 |
Total | $ 50,677 |  |  | 50,677 |
Accumulated depreciation | $ (22,606) |  |  | (22,606) |
Date of construction | 1984 |  |  |  |
Date acquired | Oct-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 50,677 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (22,606) |  |  |  |
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Huntington Breakers [Member] | Huntington Beach, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 224 |  |  |  |
Encumbrance |  |  |  | 8,194 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,467 |
Buildings and improvements |  |  |  | 7,881 |
Costs capitalized subsequent to acquisition |  |  |  | 7,159 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,474 |
Buildings and improvements |  |  |  | 15,033 |
Total | $ 18,507 |  |  | 18,507 |
Accumulated depreciation | $ (11,373) |  |  | (11,373) |
Date of construction | 1985 |  |  |  |
Date acquired | Oct-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 18,507 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,373) |  |  |  |
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Inglenook Court [Member] | Bothell, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 121 |  |  |  |
Encumbrance |  |  |  | 48,414 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,359 |
Buildings and improvements |  |  |  | 21,845 |
Costs capitalized subsequent to acquisition |  |  |  | 7,268 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,359 |
Buildings and improvements |  |  |  | 29,113 |
Total | $ 38,472 |  |  | 38,472 |
Accumulated depreciation | $ (7,266) |  |  | (7,266) |
Date of construction | 1971 |  |  |  |
Date acquired | Mar-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 38,472 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,266) |  |  |  |
Encumbered Apartment Communities [Member] | Magnolia Square [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 188 |  |  |  |
Encumbrance |  |  |  | 52,175 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 8,190 |
Buildings and improvements |  |  |  | 24,736 |
Costs capitalized subsequent to acquisition |  |  |  | 15,223 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,191 |
Buildings and improvements |  |  |  | 39,958 |
Total | $ 48,149 |  |  | 48,149 |
Accumulated depreciation | $ (15,672) |  |  | (15,672) |
Date of construction | 1963 |  |  |  |
Date acquired | Sep-07 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 48,149 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,672) |  |  |  |
Encumbered Apartment Communities [Member] | Magnolia Square [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Magnolia Square [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 400 |  |  |  |
Encumbrance |  |  |  | 46,414 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 29,551 |
Buildings and improvements |  |  |  | 69,032 |
Costs capitalized subsequent to acquisition |  |  |  | 3,935 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 29,551 |
Buildings and improvements |  |  |  | 72,967 |
Total | $ 102,518 |  |  | 102,518 |
Accumulated depreciation | $ (23,405) |  |  | (23,405) |
Date of construction | 2005 |  |  |  |
Date acquired | Sep-07 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 102,518 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (23,405) |  |  |  |
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Mill Creek at Windermere [Member] | San Ramon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 188 |  |  |  |
Encumbrance |  |  |  | 42,544 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,180 |
Buildings and improvements |  |  |  | 26,673 |
Costs capitalized subsequent to acquisition |  |  |  | 14,474 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,270 |
Buildings and improvements |  |  |  | 41,057 |
Total | $ 47,327 |  |  | 47,327 |
Accumulated depreciation | $ (21,140) |  |  | (21,140) |
Date of construction | 2000 |  |  |  |
Date acquired | May-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 47,327 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (21,140) |  |  |  |
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Mirabella [Member] | Marina Del Rey, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 472 |  |  |  |
Encumbrance |  |  |  | 61,972 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 26,697 |
Buildings and improvements |  |  |  | 106,787 |
Costs capitalized subsequent to acquisition |  |  |  | 3,280 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 26,697 |
Buildings and improvements |  |  |  | 110,067 |
Total | $ 136,764 |  |  | 136,764 |
Accumulated depreciation | $ (11,271) |  |  | (11,271) |
Date of construction | 1990 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 136,764 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,271) |  |  |  |
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Montarosa [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 390 |  |  |  |
Encumbrance |  |  |  | 44,122 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,842 |
Buildings and improvements |  |  |  | 19,776 |
Costs capitalized subsequent to acquisition |  |  |  | 21,476 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,997 |
Buildings and improvements |  |  |  | 41,097 |
Total | $ 46,094 |  |  | 46,094 |
Accumulated depreciation | $ (35,665) |  |  | (35,665) |
Date of construction | 1973 |  |  |  |
Date acquired | Dec-88 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 46,094 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (35,665) |  |  |  |
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Montclaire [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 248 |  |  |  |
Encumbrance |  |  |  | 26,475 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,857 |
Buildings and improvements |  |  |  | 41,575 |
Costs capitalized subsequent to acquisition |  |  |  | 4,077 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,858 |
Buildings and improvements |  |  |  | 45,651 |
Total | $ 59,509 |  |  | 59,509 |
Accumulated depreciation | $ (7,791) |  |  | (7,791) |
Date of construction | 1996 |  |  |  |
Date acquired | Jul-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 59,509 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,791) |  |  |  |
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Montebello [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 124 |  |  |  |
Encumbrance |  |  |  | 11,939 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,925 |
Buildings and improvements |  |  |  | 7,685 |
Costs capitalized subsequent to acquisition |  |  |  | 3,173 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,194 |
Buildings and improvements |  |  |  | 10,589 |
Total | $ 12,783 |  |  | 12,783 |
Accumulated depreciation | $ (5,420) |  |  | (5,420) |
Date of construction | 1974 |  |  |  |
Date acquired | Nov-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 12,783 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,420) |  |  |  |
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Montejo Apartments [Member] | Garden Grove, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 250 |  |  |  |
Encumbrance |  |  |  | 26,617 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,391 |
Buildings and improvements |  |  |  | 38,224 |
Costs capitalized subsequent to acquisition |  |  |  | 10,626 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,391 |
Buildings and improvements |  |  |  | 48,850 |
Total | $ 58,241 |  |  | 58,241 |
Accumulated depreciation | $ (5,230) |  |  | (5,230) |
Date of construction | 1993 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 58,241 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,230) |  |  |  |
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Park Highland [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 245 |  |  |  |
Encumbrance |  |  |  | 27,224 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,284 |
Buildings and improvements |  |  |  | 21,937 |
Costs capitalized subsequent to acquisition |  |  |  | 6,769 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,284 |
Buildings and improvements |  |  |  | 28,706 |
Total | $ 35,990 |  |  | 35,990 |
Accumulated depreciation | $ (11,712) |  |  | (11,712) |
Date of construction | 1999 |  |  |  |
Date acquired | Feb-99 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 35,990 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,712) |  |  |  |
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Park Hill at Issaquah [Member] | Issaquah, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 296 |  |  |  |
Encumbrance |  |  |  | 35,673 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,083 |
Buildings and improvements |  |  |  | 16,757 |
Costs capitalized subsequent to acquisition |  |  |  | 19,526 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,239 |
Buildings and improvements |  |  |  | 34,127 |
Total | $ 40,366 |  |  | 40,366 |
Accumulated depreciation | $ (27,669) |  |  | (27,669) |
Date of construction | 1975 |  |  |  |
Date acquired | Feb-91 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 40,366 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (27,669) |  |  |  |
Encumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Pathways at Bixby Village [Member] | Long Beach, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 396 |  |  |  |
Encumbrance |  |  |  | 45,454 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,848 |
Buildings and improvements |  |  |  | 59,606 |
Costs capitalized subsequent to acquisition |  |  |  | 9,087 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,848 |
Buildings and improvements |  |  |  | 68,693 |
Total | $ 88,541 |  |  | 88,541 |
Accumulated depreciation | $ (6,386) |  |  | (6,386) |
Date of construction | 1969 |  |  |  |
Date acquired | May-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 88,541 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,386) |  |  |  |
Encumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Piedmont [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 192 |  |  |  |
Encumbrance |  |  |  | 26,804 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,019 |
Buildings and improvements |  |  |  | 45,932 |
Costs capitalized subsequent to acquisition |  |  |  | 1,699 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,019 |
Buildings and improvements |  |  |  | 47,631 |
Total | $ 58,650 |  |  | 58,650 |
Accumulated depreciation | $ (4,847) |  |  | (4,847) |
Date of construction | 2004 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 58,650 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,847) |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Fullerton [Member] | Fullerton, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 180 |  |  |  |
Encumbrance |  |  |  | 18,078 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,760 |
Buildings and improvements |  |  |  | 31,041 |
Costs capitalized subsequent to acquisition |  |  |  | 755 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,760 |
Buildings and improvements |  |  |  | 31,796 |
Total | $ 39,556 |  |  | 39,556 |
Accumulated depreciation | $ (3,245) |  |  | (3,245) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 39,556 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,245) |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle on Lake Washington [Member] | Renton, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 253 |  |  |  |
Encumbrance |  |  |  | 38,538 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,810 |
Buildings and improvements |  |  |  | 66,401 |
Costs capitalized subsequent to acquisition |  |  |  | 2,115 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,810 |
Buildings and improvements |  |  |  | 68,516 |
Total | $ 84,326 |  |  | 84,326 |
Accumulated depreciation | $ (6,945) |  |  | (6,945) |
Date of construction | 2002 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 84,326 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,945) |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at MacArthur Ranch [Member] | Santa Ana, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 364 |  |  |  |
Encumbrance |  |  |  | 40,069 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 17,023 |
Buildings and improvements |  |  |  | 68,093 |
Costs capitalized subsequent to acquisition |  |  |  | 2,561 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 17,023 |
Buildings and improvements |  |  |  | 70,654 |
Total | $ 87,677 |  |  | 87,677 |
Accumulated depreciation | $ (7,157) |  |  | (7,157) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 87,677 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,157) |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Otay Ranch I & II [Member] | Chula Vista, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | San Clemente, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 362 |  |  |  |
Encumbrance |  |  |  | 44,804 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,292 |
Buildings and improvements |  |  |  | 77,168 |
Costs capitalized subsequent to acquisition |  |  |  | 1,576 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,292 |
Buildings and improvements |  |  |  | 78,744 |
Total | $ 98,036 |  |  | 98,036 |
Accumulated depreciation | $ (8,014) |  |  | (8,014) |
Date of construction | 2002 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 98,036 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,014) |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | Irvine, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Pinnacle at Talega [Member] | Irvine, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 200 |  |  |  |
Encumbrance |  |  |  | 20,628 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 996 |
Buildings and improvements |  |  |  | 5,582 |
Costs capitalized subsequent to acquisition |  |  |  | 10,694 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,001 |
Buildings and improvements |  |  |  | 16,271 |
Total | $ 17,272 |  |  | 17,272 |
Accumulated depreciation | $ (11,105) |  |  | (11,105) |
Date of construction | 1975 |  |  |  |
Date acquired | Apr-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 17,272 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,105) |  |  |  |
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Stevenson Place [Member] | Fremont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 100 |  |  |  |
Encumbrance |  |  |  | 12,793 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,654 |
Buildings and improvements |  |  |  | 4,918 |
Costs capitalized subsequent to acquisition |  |  |  | 10,432 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,656 |
Buildings and improvements |  |  |  | 15,348 |
Total | $ 18,004 |  |  | 18,004 |
Accumulated depreciation | $ (7,221) |  |  | (7,221) |
Date of construction | 1988 |  |  |  |
Date acquired | Sep-88 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 18,004 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,221) |  |  |  |
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Summerhill Park [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 137 |  |  |  |
Encumbrance |  |  |  | 21,279 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,228 |
Buildings and improvements |  |  |  | 36,911 |
Costs capitalized subsequent to acquisition |  |  |  | 423 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,228 |
Buildings and improvements |  |  |  | 37,334 |
Total | $ 46,562 |  |  | 46,562 |
Accumulated depreciation | $ (3,761) |  |  | (3,761) |
Date of construction | 1992 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 46,562 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,761) |  |  |  |
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | The Audrey at Belltown [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 161 |  |  |  |
Encumbrance |  |  |  | 15,666 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 0 |
Buildings and improvements |  |  |  | 8,520 |
Costs capitalized subsequent to acquisition |  |  |  | 5,984 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,353 |
Buildings and improvements |  |  |  | 12,151 |
Total | $ 14,504 |  |  | 14,504 |
Accumulated depreciation | $ (6,678) |  |  | (6,678) |
Date of construction | 1984 |  |  |  |
Date acquired | Apr-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 14,504 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,678) |  |  |  |
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Barkley [Member] | Anaheim, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 63 |  |  |  |
Encumbrance |  |  |  | 8,841 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,699 |
Buildings and improvements |  |  |  | 11,345 |
Costs capitalized subsequent to acquisition |  |  |  | 384 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,689 |
Buildings and improvements |  |  |  | 11,739 |
Total | $ 15,428 |  |  | 15,428 |
Accumulated depreciation | $ (2,136) |  |  | (2,136) |
Date of construction | 2008 |  |  |  |
Date acquired | Sep-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 15,428 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,136) |  |  |  |
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Bernard [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 184 |  |  |  |
Encumbrance |  |  |  | 59,866 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,984 |
Buildings and improvements |  |  |  | 82,286 |
Costs capitalized subsequent to acquisition |  |  |  | 405 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,984 |
Buildings and improvements |  |  |  | 82,691 |
Total | $ 102,675 |  |  | 102,675 |
Accumulated depreciation | $ (5,863) |  |  | (5,863) |
Date of construction | 2015 |  |  |  |
Date acquired | Mar-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 102,675 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,863) |  |  |  |
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Dylan [Member] | West Hollywood, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Elliot [Member] | Mukilteo, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 301 |  |  |  |
Encumbrance |  |  |  | 10,639 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,498 |
Buildings and improvements |  |  |  | 10,595 |
Costs capitalized subsequent to acquisition |  |  |  | 15,308 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,824 |
Buildings and improvements |  |  |  | 25,577 |
Total | $ 28,401 |  |  | 28,401 |
Accumulated depreciation | $ (16,550) |  |  | (16,550) |
Date of construction | 1981 |  |  |  |
Date acquired | Jan-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 28,401 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (16,550) |  |  |  |
Encumbered Apartment Communities [Member] | The Elliot [Member] | Mukilteo, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Elliot [Member] | Mukilteo, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 276 |  |  |  |
Encumbrance |  |  |  | 29,861 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,374 |
Buildings and improvements |  |  |  | 41,495 |
Costs capitalized subsequent to acquisition |  |  |  | 4,191 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,374 |
Buildings and improvements |  |  |  | 45,686 |
Total | $ 56,060 |  |  | 56,060 |
Accumulated depreciation | $ (7,652) |  |  | (7,652) |
Date of construction | 1975 |  |  |  |
Date acquired | Jun-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 56,060 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,652) |  |  |  |
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Huntington [Member] | Huntington Beach, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 187 |  |  |  |
Encumbrance |  |  |  | 54,501 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,362 |
Buildings and improvements |  |  |  | 75,641 |
Costs capitalized subsequent to acquisition |  |  |  | 770 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,362 |
Buildings and improvements |  |  |  | 76,411 |
Total | $ 95,773 |  |  | 95,773 |
Accumulated depreciation | $ (5,537) |  |  | (5,537) |
Date of construction | 2014 |  |  |  |
Date acquired | Mar-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 95,773 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,537) |  |  |  |
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Huxley [Member] | West Hollywood, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 282 |  |  |  |
Encumbrance |  |  |  | 53,055 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 33,554 |
Buildings and improvements |  |  |  | 78,292 |
Costs capitalized subsequent to acquisition |  |  |  | 4,246 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 33,554 |
Buildings and improvements |  |  |  | 82,538 |
Total | $ 116,092 |  |  | 116,092 |
Accumulated depreciation | $ (8,759) |  |  | (8,759) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 116,092 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,759) |  |  |  |
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | The Landing at Jack London Square [Member] | Oakland, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 192 |  |  |  |
Encumbrance |  |  |  | 19,752 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,560 |
Buildings and improvements |  |  |  | 6,242 |
Costs capitalized subsequent to acquisition |  |  |  | 12,093 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,565 |
Buildings and improvements |  |  |  | 18,330 |
Total | $ 19,895 |  |  | 19,895 |
Accumulated depreciation | $ (15,115) |  |  | (15,115) |
Date of construction | 1977 |  |  |  |
Date acquired | May-90 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 19,895 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,115) |  |  |  |
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Palisades [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 460 |  |  |  |
Encumbrance |  |  |  | 55,441 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 23,584 |
Buildings and improvements |  |  |  | 94,334 |
Costs capitalized subsequent to acquisition |  |  |  | 3,393 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 23,584 |
Buildings and improvements |  |  |  | 97,727 |
Total | $ 121,311 |  |  | 121,311 |
Accumulated depreciation | $ (9,922) |  |  | (9,922) |
Date of construction | 1988 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 121,311 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,922) |  |  |  |
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | The Palms at Laguna Niguel [Member] | Laguna Niguel, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 238 |  |  |  |
Encumbrance |  |  |  | 30,240 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,808 |
Buildings and improvements |  |  |  | 24,500 |
Costs capitalized subsequent to acquisition |  |  |  | 14,172 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,165 |
Buildings and improvements |  |  |  | 35,315 |
Total | $ 50,480 |  |  | 50,480 |
Accumulated depreciation | $ (19,053) |  |  | (19,053) |
Date of construction | 2000 |  |  |  |
Date acquired | Jun-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 50,480 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (19,053) |  |  |  |
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Waterford [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 404 |  |  |  |
Encumbrance |  |  |  | 52,715 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,652 |
Buildings and improvements |  |  |  | 53,336 |
Costs capitalized subsequent to acquisition |  |  |  | 4,595 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,661 |
Buildings and improvements |  |  |  | 57,922 |
Total | $ 71,583 |  |  | 71,583 |
Accumulated depreciation | $ (25,300) |  |  | (25,300) |
Date of construction | 2001 |  |  |  |
Date acquired | Jan-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 71,583 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (25,300) |  |  |  |
Encumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Tierra Vista [Member] | Oxnard, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 160 |  |  |  |
Encumbrance |  |  |  | 21,530 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,361 |
Buildings and improvements |  |  |  | 13,420 |
Costs capitalized subsequent to acquisition |  |  |  | 5,545 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,761 |
Buildings and improvements |  |  |  | 18,565 |
Total | $ 22,326 |  |  | 22,326 |
Accumulated depreciation | $ (9,050) |  |  | (9,050) |
Date of construction | 1969 |  |  |  |
Date acquired | Nov-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 22,326 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,050) |  |  |  |
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Valley Park [Member] | Fountain Valley [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 256 |  |  |  |
Encumbrance |  |  |  | 24,723 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,498 |
Buildings and improvements |  |  |  | 17,962 |
Costs capitalized subsequent to acquisition |  |  |  | 6,808 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,962 |
Buildings and improvements |  |  |  | 24,306 |
Total | $ 29,268 |  |  | 29,268 |
Accumulated depreciation | $ (12,185) |  |  | (12,185) |
Date of construction | 1970 |  |  |  |
Date acquired | Nov-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 29,268 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,185) |  |  |  |
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Villa Angelina [Member] | Placentia, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 270 |  |  |  |
Encumbrance |  |  |  | 58,828 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 38,299 |
Buildings and improvements |  |  |  | 89,365 |
Costs capitalized subsequent to acquisition |  |  |  | 1,059 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 38,299 |
Buildings and improvements |  |  |  | 90,424 |
Total | $ 128,723 |  |  | 128,723 |
Accumulated depreciation | $ (9,193) |  |  | (9,193) |
Date of construction | 2010 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 128,723 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,193) |  |  |  |
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Encumbered Apartment Communities [Member] | Villa Grenada [Member] | Santa Clara, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 156 |  |  |  |
Encumbrance |  |  |  | 5,224 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,285 |
Buildings and improvements |  |  |  | 4,980 |
Costs capitalized subsequent to acquisition |  |  |  | 3,981 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,296 |
Buildings and improvements |  |  |  | 8,950 |
Total | $ 10,246 |  |  | 10,246 |
Accumulated depreciation | $ (6,767) |  |  | (6,767) |
Date of construction | 1986 |  |  |  |
Date acquired | Nov-95 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 10,246 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,767) |  |  |  |
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Wandering Creek [Member] | Kent, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 149 |  |  |  |
Encumbrance |  |  |  | 16,924 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,118 |
Buildings and improvements |  |  |  | 7,385 |
Costs capitalized subsequent to acquisition |  |  |  | 7,984 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,797 |
Buildings and improvements |  |  |  | 14,690 |
Total | $ 18,487 |  |  | 18,487 |
Accumulated depreciation | $ (9,114) |  |  | (9,114) |
Date of construction | 1992 |  |  |  |
Date acquired | Jan-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 18,487 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,114) |  |  |  |
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Wilshire Promenade [Member] | Fullerton, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Encumbered Apartment Communities [Member] | The Avery [Member] | Anaheim, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Encumbered Apartment Communities [Member] | The Avery [Member] | Anaheim, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 31,481 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,693,968 |
Buildings and improvements |  |  |  | 6,072,893 |
Costs capitalized subsequent to acquisition |  |  |  | 977,660 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,738,155 |
Buildings and improvements |  |  |  | 7,006,366 |
Total | $ 8,744,521 |  |  | 8,744,521 |
Accumulated depreciation | (1,446,609) |  |  | (1,446,609) |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | 8,744,521 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,446,609) |  |  |  |
Unencumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | 1000 Kiely [Member] | Santa Clara, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 290 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 29,279 |
Buildings and improvements |  |  |  | 169,350 |
Costs capitalized subsequent to acquisition |  |  |  | 1,746 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 29,279 |
Buildings and improvements |  |  |  | 171,096 |
Total | $ 200,375 |  |  | 200,375 |
Accumulated depreciation | $ (11,991) |  |  | (11,991) |
Date of construction | 2014 |  |  |  |
Date acquired | Feb-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 200,375 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,991) |  |  |  |
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Eighth And Hope [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 624 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 32,136 |
Buildings and improvements |  |  |  | 128,543 |
Costs capitalized subsequent to acquisition |  |  |  | 4,416 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 32,136 |
Buildings and improvements |  |  |  | 132,959 |
Total | $ 165,095 |  |  | 165,095 |
Accumulated depreciation | $ (13,779) |  |  | (13,779) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 165,095 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,779) |  |  |  |
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Alessio [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 97 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,869 |
Buildings and improvements |  |  |  | 23,977 |
Costs capitalized subsequent to acquisition |  |  |  | 1,811 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,869 |
Buildings and improvements |  |  |  | 25,788 |
Total | $ 31,657 |  |  | 31,657 |
Accumulated depreciation | $ (7,554) |  |  | (7,554) |
Date of construction | 2010 |  |  |  |
Date acquired | Oct-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 31,657 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,554) |  |  |  |
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Allegro [Member] | Valley Village, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 194 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,923 |
Buildings and improvements |  |  |  | 47,690 |
Costs capitalized subsequent to acquisition |  |  |  | 862 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,923 |
Buildings and improvements |  |  |  | 48,552 |
Total | $ 60,475 |  |  | 60,475 |
Accumulated depreciation | $ (4,885) |  |  | (4,885) |
Date of construction | 2002 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 60,475 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,885) |  |  |  |
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Allure [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 301 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,967 |
Buildings and improvements |  |  |  | 19,728 |
Costs capitalized subsequent to acquisition |  |  |  | 7,285 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,982 |
Buildings and improvements |  |  |  | 26,998 |
Total | $ 31,980 |  |  | 31,980 |
Accumulated depreciation | $ (12,764) |  |  | (12,764) |
Date of construction | 1971 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 31,980 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,764) |  |  |  |
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Alpine Village [Member] | Alpine, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 250 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,925 |
Buildings and improvements |  |  |  | 63,712 |
Costs capitalized subsequent to acquisition |  |  |  | 7,262 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,925 |
Buildings and improvements |  |  |  | 70,974 |
Total | $ 86,899 |  |  | 86,899 |
Accumulated depreciation | $ (14,512) |  |  | (14,512) |
Date of construction | 2009 |  |  |  |
Date acquired | Dec-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 86,899 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (14,512) |  |  |  |
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Anavia [Member] | Anaheim, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 56 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,727 |
Buildings and improvements |  |  |  | 14,229 |
Costs capitalized subsequent to acquisition |  |  |  | 426 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,726 |
Buildings and improvements |  |  |  | 14,656 |
Total | $ 19,382 |  |  | 19,382 |
Accumulated depreciation | $ (1,977) |  |  | (1,977) |
Date of construction | 2009 |  |  |  |
Date acquired | Jan-13 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 19,382 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,977) |  |  |  |
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Annaliese [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 366 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 44,240 |
Buildings and improvements |  |  |  | 103,251 |
Costs capitalized subsequent to acquisition |  |  |  | 1,685 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 44,240 |
Buildings and improvements |  |  |  | 104,936 |
Total | $ 149,176 |  |  | 149,176 |
Accumulated depreciation | $ (8,143) |  |  | (8,143) |
Date of construction | 2014 |  |  |  |
Date acquired | Aug-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 149,176 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,143) |  |  |  |
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Apex [Member] | Milpitas, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 500 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 58,442 |
Buildings and improvements |  |  |  | 175,326 |
Costs capitalized subsequent to acquisition |  |  |  | 8,039 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 58,442 |
Buildings and improvements |  |  |  | 183,365 |
Total | $ 241,807 |  |  | 241,807 |
Accumulated depreciation | $ (19,062) |  |  | (19,062) |
Date of construction | 2001 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 241,807 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (19,062) |  |  |  |
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Aqua at Marina Del Rey [Member] | Marina Del Rey, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 90 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,924 |
Buildings and improvements |  |  |  | 11,862 |
Costs capitalized subsequent to acquisition |  |  |  | 1,726 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,924 |
Buildings and improvements |  |  |  | 13,588 |
Total | $ 17,512 |  |  | 17,512 |
Accumulated depreciation | $ (2,335) |  |  | (2,335) |
Date of construction | 1988 |  |  |  |
Date acquired | Oct-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 17,512 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,335) |  |  |  |
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Ascent [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 264 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 23,550 |
Buildings and improvements |  |  |  | 93,811 |
Costs capitalized subsequent to acquisition |  |  |  | 12 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 23,550 |
Buildings and improvements |  |  |  | 93,823 |
Total | $ 117,373 |  |  | 117,373 |
Accumulated depreciation | $ (136) |  |  | (136) |
Date of construction | 2014 |  |  |  |
Date acquired | Dec-16 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 117,373 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (136) |  |  |  |
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Ashton Sherman Village [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 440 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 32,379 |
Buildings and improvements |  |  |  | 137,940 |
Costs capitalized subsequent to acquisition |  |  |  | 593 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 32,379 |
Buildings and improvements |  |  |  | 138,533 |
Total | $ 170,912 |  |  | 170,912 |
Accumulated depreciation | $ (6,522) |  |  | (6,522) |
Date of construction | 2014 |  |  |  |
Date acquired | Jun-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 170,912 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,522) |  |  |  |
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Avant [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 224 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 27,235 |
Buildings and improvements |  |  |  | 64,403 |
Costs capitalized subsequent to acquisition |  |  |  | 13,349 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 27,235 |
Buildings and improvements |  |  |  | 77,752 |
Total | $ 104,987 |  |  | 104,987 |
Accumulated depreciation | $ (7,074) |  |  | (7,074) |
Date of construction | 2007 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 104,987 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,074) |  |  |  |
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Avenue 64 [Member] | Emeryville, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 166 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 0 |
Buildings and improvements |  |  |  | 49,813 |
Costs capitalized subsequent to acquisition |  |  |  | 498 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 0 |
Buildings and improvements |  |  |  | 50,311 |
Total | $ 50,311 |  |  | 50,311 |
Accumulated depreciation | $ (5,693) |  |  | (5,693) |
Date of construction | 2013 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 50,311 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,693) |  |  |  |
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Aviara [Member] | Mercer Island, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 115 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,405 |
Buildings and improvements |  |  |  | 33,585 |
Costs capitalized subsequent to acquisition |  |  |  | 1,287 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,405 |
Buildings and improvements |  |  |  | 34,872 |
Total | $ 40,277 |  |  | 40,277 |
Accumulated depreciation | $ (9,957) |  |  | (9,957) |
Date of construction | 2010 |  |  |  |
Date acquired | Aug-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 40,277 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,957) |  |  |  |
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Axis 2300 [Member] | Irvine, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 231 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 17,247 |
Buildings and improvements |  |  |  | 40,343 |
Costs capitalized subsequent to acquisition |  |  |  | 2,544 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 17,247 |
Buildings and improvements |  |  |  | 42,887 |
Total | $ 60,134 |  |  | 60,134 |
Accumulated depreciation | $ (9,707) |  |  | (9,707) |
Date of construction | 2004 |  |  |  |
Date acquired | Sep-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 60,134 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,707) |  |  |  |
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bella Villagio [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 63 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,401 |
Buildings and improvements |  |  |  | 21,803 |
Costs capitalized subsequent to acquisition |  |  |  | 856 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,401 |
Buildings and improvements |  |  |  | 22,659 |
Total | $ 28,060 |  |  | 28,060 |
Accumulated depreciation | $ (5,427) |  |  | (5,427) |
Date of construction | 2011 |  |  |  |
Date acquired | Aug-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 28,060 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,427) |  |  |  |
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bellerive [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 71 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,446 |
Buildings and improvements |  |  |  | 10,290 |
Costs capitalized subsequent to acquisition |  |  |  | 5,181 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,473 |
Buildings and improvements |  |  |  | 15,444 |
Total | $ 19,917 |  |  | 19,917 |
Accumulated depreciation | $ (6,223) |  |  | (6,223) |
Date of construction | 1974 |  |  |  |
Date acquired | Oct-06 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 19,917 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,223) |  |  |  |
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Belmont Terrace [Member] | Belmont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 165 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,771 |
Buildings and improvements |  |  |  | 50,800 |
Costs capitalized subsequent to acquisition |  |  |  | 27,370 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 28,371 |
Buildings and improvements |  |  |  | 71,570 |
Total | $ 99,941 |  |  | 99,941 |
Accumulated depreciation | $ (10,291) |  |  | (10,291) |
Date of construction | 2004 |  |  |  |
Date acquired | Dec-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 99,941 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,291) |  |  |  |
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bennett Lofts [Member] | San Francisco, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 216 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,802 |
Buildings and improvements |  |  |  | 43,209 |
Costs capitalized subsequent to acquisition |  |  |  | 2,263 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,802 |
Buildings and improvements |  |  |  | 45,472 |
Total | $ 56,274 |  |  | 56,274 |
Accumulated depreciation | $ (4,633) |  |  | (4,633) |
Date of construction | 1988 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 56,274 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,633) |  |  |  |
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bernardo Crest [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 120 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,496 |
Buildings and improvements |  |  |  | 9,913 |
Costs capitalized subsequent to acquisition |  |  |  | 2,842 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,503 |
Buildings and improvements |  |  |  | 12,748 |
Total | $ 15,251 |  |  | 15,251 |
Accumulated depreciation | $ (6,100) |  |  | (6,100) |
Date of construction | 1983 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 15,251 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,100) |  |  |  |
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bonita Cedars [Member] | Bonita, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 172 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,520 |
Buildings and improvements |  |  |  | 8,182 |
Costs capitalized subsequent to acquisition |  |  |  | 11,391 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,580 |
Buildings and improvements |  |  |  | 19,513 |
Total | $ 23,093 |  |  | 23,093 |
Accumulated depreciation | $ (14,961) |  |  | (14,961) |
Date of construction | 1978 |  |  |  |
Date acquired | Jan-96 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 23,093 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (14,961) |  |  |  |
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Boulevard [Member] | Fremont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 108 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,500 |
Buildings and improvements |  |  |  | 5,930 |
Costs capitalized subsequent to acquisition |  |  |  | 5,622 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,531 |
Buildings and improvements |  |  |  | 11,521 |
Total | $ 13,052 |  |  | 13,052 |
Accumulated depreciation | $ (7,672) |  |  | (7,672) |
Date of construction | 1986 |  |  |  |
Date acquired | Oct-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 13,052 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,672) |  |  |  |
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bridle Trails [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 264 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,623 |
Buildings and improvements |  |  |  | 10,800 |
Costs capitalized subsequent to acquisition |  |  |  | 4,523 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,656 |
Buildings and improvements |  |  |  | 15,290 |
Total | $ 17,946 |  |  | 17,946 |
Accumulated depreciation | $ (10,385) |  |  | (10,385) |
Date of construction | 1986 |  |  |  |
Date acquired | Dec-96 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 17,946 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,385) |  |  |  |
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Brighton Ridge [Member] | Renton, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 188 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,278 |
Buildings and improvements |  |  |  | 11,853 |
Costs capitalized subsequent to acquisition |  |  |  | 8,069 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,293 |
Buildings and improvements |  |  |  | 19,907 |
Total | $ 25,200 |  |  | 25,200 |
Accumulated depreciation | $ (11,273) |  |  | (11,273) |
Date of construction | 1989 |  |  |  |
Date acquired | Jan-95 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 25,200 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,273) |  |  |  |
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bristol Commons [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 115 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 8,557 |
Buildings and improvements |  |  |  | 34,235 |
Costs capitalized subsequent to acquisition |  |  |  | 2,111 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,557 |
Buildings and improvements |  |  |  | 36,346 |
Total | $ 44,903 |  |  | 44,903 |
Accumulated depreciation | $ (8,028) |  |  | (8,028) |
Date of construction | 2009 |  |  |  |
Date acquired | Dec-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 44,903 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,028) |  |  |  |
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | 416 on Broadway [Member] | Glendale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 456 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,498 |
Buildings and improvements |  |  |  | 27,871 |
Costs capitalized subsequent to acquisition |  |  |  | 63,985 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,639 |
Buildings and improvements |  |  |  | 91,715 |
Total | $ 103,354 |  |  | 103,354 |
Accumulated depreciation | $ (32,678) |  |  | (32,678) |
Date of construction | 1968 |  |  |  |
Date acquired | Mar-98 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 103,354 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (32,678) |  |  |  |
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Bunker Hill [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 564 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,953 |
Buildings and improvements |  |  |  | 25,254 |
Costs capitalized subsequent to acquisition |  |  |  | 5,444 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,075 |
Buildings and improvements |  |  |  | 30,576 |
Total | $ 41,651 |  |  | 41,651 |
Accumulated depreciation | $ (20,556) |  |  | (20,556) |
Date of construction | 1985 |  |  |  |
Date acquired | Jul-96 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 41,651 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (20,556) |  |  |  |
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Camarillo Oaks [Member] | Camarillo, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 320 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 18,185 |
Buildings and improvements |  |  |  | 72,739 |
Costs capitalized subsequent to acquisition |  |  |  | 1,619 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 18,185 |
Buildings and improvements |  |  |  | 74,358 |
Total | $ 92,543 |  |  | 92,543 |
Accumulated depreciation | $ (7,679) |  |  | (7,679) |
Date of construction | 1998 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 92,543 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,679) |  |  |  |
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cambridge Park [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Camino Ruiz Square [Member] | Camarillo, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 159 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,871 |
Buildings and improvements |  |  |  | 26,119 |
Costs capitalized subsequent to acquisition |  |  |  | 1,567 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,931 |
Buildings and improvements |  |  |  | 27,626 |
Total | $ 34,557 |  |  | 34,557 |
Accumulated depreciation | $ (9,542) |  |  | (9,542) |
Date of construction | 1990 |  |  |  |
Date acquired | Dec-06 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 34,557 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,542) |  |  |  |
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 250 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,692 |
Buildings and improvements |  |  |  | 18,288 |
Costs capitalized subsequent to acquisition |  |  |  | 6,623 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,693 |
Buildings and improvements |  |  |  | 24,910 |
Total | $ 29,603 |  |  | 29,603 |
Accumulated depreciation | $ (11,707) |  |  | (11,707) |
Date of construction | 1990 |  |  |  |
Date acquired | Oct-03 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 29,603 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,707) |  |  |  |
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Canyon Pointe [Member] | Bothell, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 102 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,337 |
Buildings and improvements |  |  |  | 13,320 |
Costs capitalized subsequent to acquisition |  |  |  | 8,626 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,048 |
Buildings and improvements |  |  |  | 21,235 |
Total | $ 25,283 |  |  | 25,283 |
Accumulated depreciation | $ (11,437) |  |  | (11,437) |
Date of construction | 1961 |  |  |  |
Date acquired | Sep-01 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 25,283 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,437) |  |  |  |
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Capri at Sunny Hills [Member] | Fullerton, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 356 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 16,725 |
Buildings and improvements |  |  |  | 66,901 |
Costs capitalized subsequent to acquisition |  |  |  | 3,866 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 16,725 |
Buildings and improvements |  |  |  | 70,767 |
Total | $ 87,492 |  |  | 87,492 |
Accumulated depreciation | $ (7,321) |  |  | (7,321) |
Date of construction | 1989 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 87,492 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,321) |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Landing [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 246 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 14,968 |
Buildings and improvements |  |  |  | 59,871 |
Costs capitalized subsequent to acquisition |  |  |  | 2,007 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 14,968 |
Buildings and improvements |  |  |  | 61,878 |
Total | $ 76,846 |  |  | 76,846 |
Accumulated depreciation | $ (6,271) |  |  | (6,271) |
Date of construction | 1989 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 76,846 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,271) |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Carnel Summit [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 216 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,149 |
Buildings and improvements |  |  |  | 16,028 |
Costs capitalized subsequent to acquisition |  |  |  | 3,066 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,833 |
Buildings and improvements |  |  |  | 18,410 |
Total | $ 23,243 |  |  | 23,243 |
Accumulated depreciation | $ (12,291) |  |  | (12,291) |
Date of construction | 1998 |  |  |  |
Date acquired | Dec-98 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 23,243 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,291) |  |  |  |
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Castle Creek [Member] | New Castle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 128 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,714 |
Buildings and improvements |  |  |  | 26,856 |
Costs capitalized subsequent to acquisition |  |  |  | 710 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,714 |
Buildings and improvements |  |  |  | 27,566 |
Total | $ 34,280 |  |  | 34,280 |
Accumulated depreciation | $ (2,811) |  |  | (2,811) |
Date of construction | 1987 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 34,280 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,811) |  |  |  |
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Catalina Gardens [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 239 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,841 |
Buildings and improvements |  |  |  | 45,320 |
Costs capitalized subsequent to acquisition |  |  |  | 5,848 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,906 |
Buildings and improvements |  |  |  | 51,103 |
Total | $ 63,009 |  |  | 63,009 |
Accumulated depreciation | $ (21,004) |  |  | (21,004) |
Date of construction | 1962 |  |  |  |
Date acquired | Jan-06 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 63,009 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (21,004) |  |  |  |
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | CBC Apartments [Member] | Goleta, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 180 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,543 |
Buildings and improvements |  |  |  | 16,442 |
Costs capitalized subsequent to acquisition |  |  |  | 5,457 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,652 |
Buildings and improvements |  |  |  | 21,790 |
Total | $ 27,442 |  |  | 27,442 |
Accumulated depreciation | $ (9,597) |  |  | (9,597) |
Date of construction | 1984 |  |  |  |
Date acquired | Jan-05 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 27,442 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,597) |  |  |  |
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cedar Terrace [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 224 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,405 |
Buildings and improvements |  |  |  | 7,743 |
Costs capitalized subsequent to acquisition |  |  |  | 20,221 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,442 |
Buildings and improvements |  |  |  | 27,927 |
Total | $ 31,369 |  |  | 31,369 |
Accumulated depreciation | $ (13,724) |  |  | (13,724) |
Date of construction | 1974 |  |  |  |
Date acquired | Jun-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 31,369 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,724) |  |  |  |
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | CentrePointe [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 96 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,582 |
Buildings and improvements |  |  |  | 15,689 |
Costs capitalized subsequent to acquisition |  |  |  | 1,387 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,582 |
Buildings and improvements |  |  |  | 17,076 |
Total | $ 23,658 |  |  | 23,658 |
Accumulated depreciation | $ (5,165) |  |  | (5,165) |
Date of construction | 2002 |  |  |  |
Date acquired | Jul-08 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 23,658 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,165) |  |  |  |
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Chestnut Street [Member] | Santa Cruz, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 76 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,276 |
Buildings and improvements |  |  |  | 22,226 |
Costs capitalized subsequent to acquisition |  |  |  | 179 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,276 |
Buildings and improvements |  |  |  | 22,405 |
Total | $ 29,681 |  |  | 29,681 |
Accumulated depreciation | $ (1,973) |  |  | (1,973) |
Date of construction | 2013 |  |  |  |
Date acquired | May-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 29,681 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,973) |  |  |  |
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Collins On Pine [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 169 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,801 |
Buildings and improvements |  |  |  | 17,415 |
Costs capitalized subsequent to acquisition |  |  |  | 2,368 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,801 |
Buildings and improvements |  |  |  | 19,783 |
Total | $ 25,584 |  |  | 25,584 |
Accumulated depreciation | $ (4,515) |  |  | (4,515) |
Date of construction | 1978 |  |  |  |
Date acquired | Nov-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 25,584 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,515) |  |  |  |
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Corbella at Juanita Bay [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 308 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,912 |
Buildings and improvements |  |  |  | 55,649 |
Costs capitalized subsequent to acquisition |  |  |  | 1,103 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,912 |
Buildings and improvements |  |  |  | 56,752 |
Total | $ 70,664 |  |  | 70,664 |
Accumulated depreciation | $ (5,799) |  |  | (5,799) |
Date of construction | 1999 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 70,664 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,799) |  |  |  |
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Cortesia [Member] | Rancho Santa Margarita, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 180 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,174 |
Buildings and improvements |  |  |  | 16,583 |
Costs capitalized subsequent to acquisition |  |  |  | 3,902 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,187 |
Buildings and improvements |  |  |  | 20,472 |
Total | $ 24,659 |  |  | 24,659 |
Accumulated depreciation | $ (10,111) |  |  | (10,111) |
Date of construction | 1976 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 24,659 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,111) |  |  |  |
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Country Villas [Member] | Oceanside, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 400 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 37,579 |
Buildings and improvements |  |  |  | 87,685 |
Costs capitalized subsequent to acquisition |  |  |  | 3,158 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 37,579 |
Buildings and improvements |  |  |  | 90,843 |
Total | $ 128,422 |  |  | 128,422 |
Accumulated depreciation | $ (9,277) |  |  | (9,277) |
Date of construction | 1992 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 128,422 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,277) |  |  |  |
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Crow Canyon [Member] | San Ramon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 171 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,478 |
Buildings and improvements |  |  |  | 50,116 |
Costs capitalized subsequent to acquisition |  |  |  | 1,629 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 21,478 |
Buildings and improvements |  |  |  | 51,745 |
Total | $ 73,223 |  |  | 73,223 |
Accumulated depreciation | $ (5,335) |  |  | (5,335) |
Date of construction | 1996 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 73,223 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,335) |  |  |  |
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Deer Valley [Member] | San Rafael, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 126 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,470 |
Buildings and improvements |  |  |  | 22,511 |
Costs capitalized subsequent to acquisition |  |  |  | 1,056 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,470 |
Buildings and improvements |  |  |  | 23,567 |
Total | $ 31,037 |  |  | 31,037 |
Accumulated depreciation | $ (4,127) |  |  | (4,127) |
Date of construction | 2005 |  |  |  |
Date acquired | Dec-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 31,037 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,127) |  |  |  |
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Delano [Member] | Redmond, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 276 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,470 |
Buildings and improvements |  |  |  | 13,786 |
Costs capitalized subsequent to acquisition |  |  |  | 3,685 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,482 |
Buildings and improvements |  |  |  | 17,459 |
Total | $ 20,941 |  |  | 20,941 |
Accumulated depreciation | $ (8,659) |  |  | (8,659) |
Date of construction | 1988 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 20,941 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,659) |  |  |  |
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Devonshire [Member] | Hemet, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 379 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 23,848 |
Buildings and improvements |  |  |  | 95,394 |
Costs capitalized subsequent to acquisition |  |  |  | 1,141 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 23,848 |
Buildings and improvements |  |  |  | 96,535 |
Total | $ 120,383 |  |  | 120,383 |
Accumulated depreciation | $ (10,174) |  |  | (10,174) |
Date of construction | 2013 |  |  |  |
Date acquired | Nov-13 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 120,383 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,174) |  |  |  |
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Domain [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 160 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 8,458 |
Buildings and improvements |  |  |  | 33,832 |
Costs capitalized subsequent to acquisition |  |  |  | 1,203 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,458 |
Buildings and improvements |  |  |  | 35,035 |
Total | $ 43,493 |  |  | 43,493 |
Accumulated depreciation | $ (3,605) |  |  | (3,605) |
Date of construction | 1989 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 43,493 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,605) |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Pointe [Member] | Diamond Bar, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 180 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,449 |
Buildings and improvements |  |  |  | 7,801 |
Costs capitalized subsequent to acquisition |  |  |  | 4,937 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,449 |
Buildings and improvements |  |  |  | 12,738 |
Total | $ 16,187 |  |  | 16,187 |
Accumulated depreciation | $ (8,907) |  |  | (8,907) |
Date of construction | 1987 |  |  |  |
Date acquired | Nov-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 16,187 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,907) |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerald Ridge [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 144 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,378 |
Buildings and improvements |  |  |  | 53,240 |
Costs capitalized subsequent to acquisition |  |  |  | 9 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,378 |
Buildings and improvements |  |  |  | 53,249 |
Total | $ 66,627 |  |  | 66,627 |
Accumulated depreciation | $ (77) |  |  | (77) |
Date of construction | 2012 |  |  |  |
Date acquired | Dec-16 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 66,627 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (77) |  |  |  |
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Emerson Valley Village [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 183 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,397 |
Buildings and improvements |  |  |  | 71,135 |
Costs capitalized subsequent to acquisition |  |  |  | 858 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 21,397 |
Buildings and improvements |  |  |  | 71,993 |
Total | $ 93,390 |  |  | 93,390 |
Accumulated depreciation | $ (2,637) |  |  | (2,637) |
Date of construction | 2014 |  |  |  |
Date acquired | Dec-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 93,390 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,637) |  |  |  |
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Enso [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 278 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 18,170 |
Buildings and improvements |  |  |  | 40,086 |
Costs capitalized subsequent to acquisition |  |  |  | 11,222 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 18,429 |
Buildings and improvements |  |  |  | 51,049 |
Total | $ 69,478 |  |  | 69,478 |
Accumulated depreciation | $ (21,749) |  |  | (21,749) |
Date of construction | 2002 |  |  |  |
Date acquired | Apr-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 69,478 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (21,749) |  |  |  |
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Esplanade [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 349 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,537 |
Buildings and improvements |  |  |  | 146,099 |
Costs capitalized subsequent to acquisition |  |  |  | 4,587 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 21,537 |
Buildings and improvements |  |  |  | 150,686 |
Total | $ 172,223 |  |  | 172,223 |
Accumulated depreciation | $ (24,175) |  |  | (24,175) |
Date of construction | 2008 |  |  |  |
Date acquired | Apr-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 172,223 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (24,175) |  |  |  |
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Essex Skyline [Member] | Santa Ana, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 200 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,566 |
Buildings and improvements |  |  |  | 13,395 |
Costs capitalized subsequent to acquisition |  |  |  | 4,936 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,649 |
Buildings and improvements |  |  |  | 18,248 |
Total | $ 21,897 |  |  | 21,897 |
Accumulated depreciation | $ (11,867) |  |  | (11,867) |
Date of construction | 1990 |  |  |  |
Date acquired | Jun-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 21,897 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,867) |  |  |  |
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Evergreen Heights [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 74 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 0 |
Buildings and improvements |  |  |  | 7,850 |
Costs capitalized subsequent to acquisition |  |  |  | 7,136 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9 |
Buildings and improvements |  |  |  | 14,977 |
Total | $ 14,986 |  |  | 14,986 |
Accumulated depreciation | $ (8,513) |  |  | (8,513) |
Date of construction | 1972 |  |  |  |
Date acquired | Jun-99 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 14,986 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,513) |  |  |  |
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fairway Apartments at Big Canyon [Member] | Newport Beach, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 28 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 194 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,296 |
Buildings and improvements |  |  |  | 15,564 |
Costs capitalized subsequent to acquisition |  |  |  | 2,784 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,297 |
Buildings and improvements |  |  |  | 18,347 |
Total | $ 23,644 |  |  | 23,644 |
Accumulated depreciation | $ (8,155) |  |  | (8,155) |
Date of construction | 1997 |  |  |  |
Date acquired | Oct-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 23,644 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,155) |  |  |  |
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fairwood Pond [Member] | Renton, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 394 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,435 |
Buildings and improvements |  |  |  | 9,821 |
Costs capitalized subsequent to acquisition |  |  |  | 38,221 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,440 |
Buildings and improvements |  |  |  | 48,037 |
Total | $ 50,477 |  |  | 50,477 |
Accumulated depreciation | $ (34,450) |  |  | (34,450) |
Date of construction | 1978 |  |  |  |
Date acquired | Mar-90 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 50,477 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (34,450) |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Commons [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 176 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,875 |
Buildings and improvements |  |  |  | 13,992 |
Costs capitalized subsequent to acquisition |  |  |  | 8,902 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,964 |
Buildings and improvements |  |  |  | 22,805 |
Total | $ 28,769 |  |  | 28,769 |
Accumulated depreciation | $ (13,660) |  |  | (13,660) |
Date of construction | 1985 |  |  |  |
Date acquired | Feb-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 28,769 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,660) |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Foothill Gardens/Twin Creeks [Member] | San Ramon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 192 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,731 |
Buildings and improvements |  |  |  | 14,530 |
Costs capitalized subsequent to acquisition |  |  |  | 2,101 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,731 |
Buildings and improvements |  |  |  | 16,631 |
Total | $ 20,362 |  |  | 20,362 |
Accumulated depreciation | $ (7,661) |  |  | (7,661) |
Date of construction | 1998 |  |  |  |
Date acquired | Oct-03 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 20,362 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,661) |  |  |  |
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Forest View [Member] | Renton, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 320 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,702 |
Buildings and improvements |  |  |  | 27,306 |
Costs capitalized subsequent to acquisition |  |  |  | 10,809 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,585 |
Buildings and improvements |  |  |  | 38,232 |
Total | $ 44,817 |  |  | 44,817 |
Accumulated depreciation | $ (21,314) |  |  | (21,314) |
Date of construction | 2000 |  |  |  |
Date acquired | Mar-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 44,817 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (21,314) |  |  |  |
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fountain Court [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 171 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 8,879 |
Buildings and improvements |  |  |  | 52,351 |
Costs capitalized subsequent to acquisition |  |  |  | 2,621 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,879 |
Buildings and improvements |  |  |  | 54,972 |
Total | $ 63,851 |  |  | 63,851 |
Accumulated depreciation | $ (13,809) |  |  | (13,809) |
Date of construction | 2010 |  |  |  |
Date acquired | Apr-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 63,851 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,809) |  |  |  |
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fourth & U [Member] | Berkeley, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 443 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 39,731 |
Buildings and improvements |  |  |  | 92,706 |
Costs capitalized subsequent to acquisition |  |  |  | 18,477 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 39,731 |
Buildings and improvements |  |  |  | 111,183 |
Total | $ 150,914 |  |  | 150,914 |
Accumulated depreciation | $ (15,448) |  |  | (15,448) |
Date of construction | 1968 |  |  |  |
Date acquired | Feb-13 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 150,914 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (15,448) |  |  |  |
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Fox Plaza [Member] | San Francisco, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 697 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 22,000 |
Buildings and improvements |  |  |  | 94,681 |
Costs capitalized subsequent to acquisition |  |  |  | 21,533 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 22,000 |
Buildings and improvements |  |  |  | 116,214 |
Total | $ 138,214 |  |  | 138,214 |
Accumulated depreciation | $ (44,137) |  |  | (44,137) |
Date of construction | 1948 |  |  |  |
Date acquired | Sep-06 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 138,214 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (44,137) |  |  |  |
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Hillsdale Garden Apartments [Member] | San Mateo, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 108 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,078 |
Buildings and improvements |  |  |  | 16,877 |
Costs capitalized subsequent to acquisition |  |  |  | 2,675 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,208 |
Buildings and improvements |  |  |  | 19,422 |
Total | $ 23,630 |  |  | 23,630 |
Accumulated depreciation | $ (6,308) |  |  | (6,308) |
Date of construction | 1965 |  |  |  |
Date acquired | Mar-07 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 23,630 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,308) |  |  |  |
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Hope Ranch Collection [Member] | Santa Barbara, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 295 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 14,558 |
Buildings and improvements |  |  |  | 69,417 |
Costs capitalized subsequent to acquisition |  |  |  | 3,849 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 14,558 |
Buildings and improvements |  |  |  | 73,266 |
Total | $ 87,824 |  |  | 87,824 |
Accumulated depreciation | $ (18,880) |  |  | (18,880) |
Date of construction | 2010 |  |  |  |
Date acquired | Mar-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 87,824 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (18,880) |  |  |  |
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Joule [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 196 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,023 |
Buildings and improvements |  |  |  | 9,527 |
Costs capitalized subsequent to acquisition |  |  |  | 12,514 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,031 |
Buildings and improvements |  |  |  | 22,033 |
Total | $ 26,064 |  |  | 26,064 |
Accumulated depreciation | $ (12,625) |  |  | (12,625) |
Date of construction | 1979 |  |  |  |
Date acquired | Jun-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 26,064 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,625) |  |  |  |
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Kings Road [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 150 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 17,774 |
Buildings and improvements |  |  |  | 41,473 |
Costs capitalized subsequent to acquisition |  |  |  | 851 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 17,774 |
Buildings and improvements |  |  |  | 42,324 |
Total | $ 60,098 |  |  | 60,098 |
Accumulated depreciation | $ (4,330) |  |  | (4,330) |
Date of construction | 1973 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 60,098 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,330) |  |  |  |
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lafayette Highlands [Member] | Lafayette, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 308 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 38,155 |
Buildings and improvements |  |  |  | 89,028 |
Costs capitalized subsequent to acquisition |  |  |  | 4,172 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 38,155 |
Buildings and improvements |  |  |  | 93,200 |
Total | $ 131,355 |  |  | 131,355 |
Accumulated depreciation | $ (10,025) |  |  | (10,025) |
Date of construction | 1988 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 131,355 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,025) |  |  |  |
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lakeshore Landing [Member] | San Mateo, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 164 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,559 |
Buildings and improvements |  |  |  | 6,430 |
Costs capitalized subsequent to acquisition |  |  |  | 5,701 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,595 |
Buildings and improvements |  |  |  | 12,095 |
Total | $ 13,690 |  |  | 13,690 |
Accumulated depreciation | $ (8,373) |  |  | (8,373) |
Date of construction | 1981 |  |  |  |
Date acquired | Dec-96 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 13,690 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,373) |  |  |  |
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Laurels at Mill Creek [Member] | Mill Creek, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 336 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 45,532 |
Buildings and improvements |  |  |  | 106,735 |
Costs capitalized subsequent to acquisition |  |  |  | 517 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 45,532 |
Buildings and improvements |  |  |  | 107,252 |
Total | $ 152,784 |  |  | 152,784 |
Accumulated depreciation | $ (13,299) |  |  | (13,299) |
Date of construction | 2012 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 152,784 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,299) |  |  |  |
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Lawrence Station [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 140 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,090 |
Buildings and improvements |  |  |  | 7,421 |
Costs capitalized subsequent to acquisition |  |  |  | 11,503 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,092 |
Buildings and improvements |  |  |  | 18,922 |
Total | $ 22,014 |  |  | 22,014 |
Accumulated depreciation | $ (13,388) |  |  | (13,388) |
Date of construction | 1975 |  |  |  |
Date acquired | Feb-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 22,014 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,388) |  |  |  |
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Le Parc [Member] | Santa Clara, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 202 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,700 |
Buildings and improvements |  |  |  | 18,605 |
Costs capitalized subsequent to acquisition |  |  |  | 7,913 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,760 |
Buildings and improvements |  |  |  | 26,458 |
Total | $ 31,218 |  |  | 31,218 |
Accumulated depreciation | $ (12,247) |  |  | (12,247) |
Date of construction | 1987 |  |  |  |
Date acquired | Sep-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 31,218 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,247) |  |  |  |
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marbrisa [Member] | Long Beach, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 101 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 0 |
Buildings and improvements |  |  |  | 28,167 |
Costs capitalized subsequent to acquisition |  |  |  | 42,537 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 0 |
Buildings and improvements |  |  |  | 70,704 |
Total | $ 70,704 |  |  | 70,704 |
Accumulated depreciation | $ (20,352) |  |  | (20,352) |
Date of construction | 1971 |  |  |  |
Date acquired | Jan-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 70,704 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (20,352) |  |  |  |
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marina City Club [Member] | Marina Del Rey, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 292 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,320 |
Buildings and improvements |  |  |  | 16,431 |
Costs capitalized subsequent to acquisition |  |  |  | 13,464 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,324 |
Buildings and improvements |  |  |  | 29,891 |
Total | $ 35,215 |  |  | 35,215 |
Accumulated depreciation | $ (20,354) |  |  | (20,354) |
Date of construction | 1974 |  |  |  |
Date acquired | Jun-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 35,215 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (20,354) |  |  |  |
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Marina Cove [Member] | Santa Clara, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 105 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,555 |
Buildings and improvements |  |  |  | 6,103 |
Costs capitalized subsequent to acquisition |  |  |  | 2,218 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,562 |
Buildings and improvements |  |  |  | 8,314 |
Total | $ 9,876 |  |  | 9,876 |
Accumulated depreciation | $ (4,954) |  |  | (4,954) |
Date of construction | 1987 |  |  |  |
Date acquired | May-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 9,876 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,954) |  |  |  |
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mariner's Place [Member] | Oxnard, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 360 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,421 |
Buildings and improvements |  |  |  | 114,376 |
Costs capitalized subsequent to acquisition |  |  |  | 121,769 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 42,001 |
Buildings and improvements |  |  |  | 215,565 |
Total | $ 257,566 |  |  | 257,566 |
Accumulated depreciation | $ (12,003) |  |  | (12,003) |
Date of construction | 2014 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 257,566 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,003) |  |  |  |
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | MB 360 [Member] | San Francisco, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 133 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,888 |
Buildings and improvements |  |  |  | 7,498 |
Costs capitalized subsequent to acquisition |  |  |  | 1,501 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,894 |
Buildings and improvements |  |  |  | 8,993 |
Total | $ 10,887 |  |  | 10,887 |
Accumulated depreciation | $ (4,323) |  |  | (4,323) |
Date of construction | 1963 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 10,887 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,323) |  |  |  |
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mesa Village [Member] | Clairemont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 103 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,012 |
Buildings and improvements |  |  |  | 39,982 |
Costs capitalized subsequent to acquisition |  |  |  | 182 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,012 |
Buildings and improvements |  |  |  | 40,164 |
Total | $ 51,176 |  |  | 51,176 |
Accumulated depreciation | $ (1,363) |  |  | (1,363) |
Date of construction | 2015 |  |  |  |
Date acquired | Jan-16 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 51,176 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,363) |  |  |  |
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mio [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 354 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,165 |
Buildings and improvements |  |  |  | 28,459 |
Costs capitalized subsequent to acquisition |  |  |  | 9,962 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,186 |
Buildings and improvements |  |  |  | 38,400 |
Total | $ 45,586 |  |  | 45,586 |
Accumulated depreciation | $ (20,783) |  |  | (20,783) |
Date of construction | 1982 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 45,586 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (20,783) |  |  |  |
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mira Monte [Member] | Mira Mesa, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 236 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,791 |
Buildings and improvements |  |  |  | 23,075 |
Costs capitalized subsequent to acquisition |  |  |  | 13,759 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,886 |
Buildings and improvements |  |  |  | 36,739 |
Total | $ 44,625 |  |  | 44,625 |
Accumulated depreciation | $ (22,818) |  |  | (22,818) |
Date of construction | 1988 |  |  |  |
Date acquired | Aug-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 44,625 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (22,818) |  |  |  |
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Miracle Mile Marbella [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 282 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,099 |
Buildings and improvements |  |  |  | 38,778 |
Costs capitalized subsequent to acquisition |  |  |  | 5,762 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,167 |
Buildings and improvements |  |  |  | 44,472 |
Total | $ 54,639 |  |  | 54,639 |
Accumulated depreciation | $ (18,507) |  |  | (18,507) |
Date of construction | 1984 |  |  |  |
Date acquired | Jul-05 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 54,639 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (18,507) |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Hills [Member] | Oceanside, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 453 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 46,499 |
Buildings and improvements |  |  |  | 108,498 |
Costs capitalized subsequent to acquisition |  |  |  | 2,168 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 46,499 |
Buildings and improvements |  |  |  | 110,666 |
Total | $ 157,165 |  |  | 157,165 |
Accumulated depreciation | $ (11,305) |  |  | (11,305) |
Date of construction | 1995 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 157,165 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,305) |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks [Member] | Fremont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 336 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 31,429 |
Buildings and improvements |  |  |  | 73,334 |
Costs capitalized subsequent to acquisition |  |  |  | 3,170 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 31,429 |
Buildings and improvements |  |  |  | 76,504 |
Total | $ 107,933 |  |  | 107,933 |
Accumulated depreciation | $ (7,962) |  |  | (7,962) |
Date of construction | 1989 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 107,933 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,962) |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Mission Peaks II [Member] | Fremont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 122 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,349 |
Buildings and improvements |  |  |  | 5,579 |
Costs capitalized subsequent to acquisition |  |  |  | 6,117 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,424 |
Buildings and improvements |  |  |  | 11,621 |
Total | $ 14,045 |  |  | 14,045 |
Accumulated depreciation | $ (6,834) |  |  | (6,834) |
Date of construction | 1974 |  |  |  |
Date acquired | Jul-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 14,045 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,834) |  |  |  |
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Monterey Villas [Member] | Oxnard, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Muse [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 152 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,822 |
Buildings and improvements |  |  |  | 33,436 |
Costs capitalized subsequent to acquisition |  |  |  | 2,457 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,823 |
Buildings and improvements |  |  |  | 35,892 |
Total | $ 43,715 |  |  | 43,715 |
Accumulated depreciation | $ (9,961) |  |  | (9,961) |
Date of construction | 2011 |  |  |  |
Date acquired | Feb-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 43,715 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,961) |  |  |  |
Unencumbered Apartment Communities [Member] | Muse [Member] | Hollywood, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Muse [Member] | Hollywood, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 117 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,864 |
Buildings and improvements |  |  |  | 32,348 |
Costs capitalized subsequent to acquisition |  |  |  | 934 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,864 |
Buildings and improvements |  |  |  | 33,282 |
Total | $ 47,146 |  |  | 47,146 |
Accumulated depreciation | $ (3,438) |  |  | (3,438) |
Date of construction | 2002 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 47,146 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,438) |  |  |  |
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Museum Park [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 301 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 32,230 |
Buildings and improvements |  |  |  | 77,320 |
Costs capitalized subsequent to acquisition |  |  |  | 589 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 32,230 |
Buildings and improvements |  |  |  | 77,909 |
Total | $ 110,139 |  |  | 110,139 |
Accumulated depreciation | $ (6,431) |  |  | (6,431) |
Date of construction | 2013 |  |  |  |
Date acquired | Jul-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 110,139 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,431) |  |  |  |
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Paragon Apartments [Member] | Fremont, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 90 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,710 |
Buildings and improvements |  |  |  | 18,839 |
Costs capitalized subsequent to acquisition |  |  |  | 2,785 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,710 |
Buildings and improvements |  |  |  | 21,624 |
Total | $ 26,334 |  |  | 26,334 |
Accumulated depreciation | $ (3,739) |  |  | (3,739) |
Date of construction | 2002 |  |  |  |
Date acquired | Jun-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 26,334 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,739) |  |  |  |
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park Catalina [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Anaheim, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 320 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,894 |
Buildings and improvements |  |  |  | 63,574 |
Costs capitalized subsequent to acquisition |  |  |  | 1,727 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 15,894 |
Buildings and improvements |  |  |  | 65,301 |
Total | $ 81,195 |  |  | 81,195 |
Accumulated depreciation | $ (6,673) |  |  | (6,673) |
Date of construction | 2008 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 81,195 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,673) |  |  |  |
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Irvine, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park Viridian [Member] | Irvine, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 126 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,424 |
Buildings and improvements |  |  |  | 21,988 |
Costs capitalized subsequent to acquisition |  |  |  | 11,278 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,424 |
Buildings and improvements |  |  |  | 33,266 |
Total | $ 42,690 |  |  | 42,690 |
Accumulated depreciation | $ (5,609) |  |  | (5,609) |
Date of construction | 1958 |  |  |  |
Date acquired | Sep-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 42,690 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,609) |  |  |  |
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Park West [Member] | San Francisco, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 240 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 10,680 |
Buildings and improvements |  |  |  | 42,722 |
Costs capitalized subsequent to acquisition |  |  |  | 1,896 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,680 |
Buildings and improvements |  |  |  | 44,618 |
Total | $ 55,298 |  |  | 55,298 |
Accumulated depreciation | $ (4,667) |  |  | (4,667) |
Date of construction | 1989 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 55,298 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,667) |  |  |  |
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Parkwood at Mill Creek [Member] | Mill Creek, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 28 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 0 |
Buildings and improvements |  |  |  | 1,711 |
Costs capitalized subsequent to acquisition |  |  |  | 519 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6 |
Buildings and improvements |  |  |  | 2,224 |
Total | $ 2,230 |  |  | 2,230 |
Accumulated depreciation | $ (1,344) |  |  | (1,344) |
Date of construction | 1973 |  |  |  |
Date acquired | Dec-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 2,230 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,344) |  |  |  |
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pinehurst [Member] | Ventura, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 24 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 268 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 14,647 |
Buildings and improvements |  |  |  | 58,586 |
Costs capitalized subsequent to acquisition |  |  |  | 1,911 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 14,647 |
Buildings and improvements |  |  |  | 60,497 |
Total | $ 75,144 |  |  | 75,144 |
Accumulated depreciation | $ (6,089) |  |  | (6,089) |
Date of construction | 2000 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 75,144 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,089) |  |  |  |
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pinnacle Sonata [Member] | Bothell, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pointe at Cupertinoe [Member] | Cupertino, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 116 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,505 |
Buildings and improvements |  |  |  | 17,605 |
Costs capitalized subsequent to acquisition |  |  |  | 11,631 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,505 |
Buildings and improvements |  |  |  | 29,236 |
Total | $ 33,741 |  |  | 33,741 |
Accumulated depreciation | $ (13,938) |  |  | (13,938) |
Date of construction | 1963 |  |  |  |
Date acquired | Aug-98 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 33,741 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (13,938) |  |  |  |
Unencumbered Apartment Communities [Member] | Pinnacle At Cupertino [Member] | Cupertino, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Pinnacle At Cupertino [Member] | Cupertino, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 264 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 11,702 |
Buildings and improvements |  |  |  | 152,336 |
Costs capitalized subsequent to acquisition |  |  |  | (39) |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 11,702 |
Buildings and improvements |  |  |  | 152,297 |
Total | $ 163,999 |  |  | 163,999 |
Accumulated depreciation | $ (14,159) |  |  | (14,159) |
Date of construction | 2015 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 163,999 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (14,159) |  |  |  |
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Radius [Member] | Redwood City, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 100 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,873 |
Buildings and improvements |  |  |  | 16,037 |
Costs capitalized subsequent to acquisition |  |  |  | 7,788 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,873 |
Buildings and improvements |  |  |  | 23,825 |
Total | $ 30,698 |  |  | 30,698 |
Accumulated depreciation | $ (5,865) |  |  | (5,865) |
Date of construction | 1970 |  |  |  |
Date acquired | Jan-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 30,698 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,865) |  |  |  |
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Reed Square [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 75 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,184 |
Buildings and improvements |  |  |  | 12,737 |
Costs capitalized subsequent to acquisition |  |  |  | 3,066 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,184 |
Buildings and improvements |  |  |  | 15,803 |
Total | $ 18,987 |  |  | 18,987 |
Accumulated depreciation | $ (4,623) |  |  | (4,623) |
Date of construction | 1989 |  |  |  |
Date acquired | Dec-09 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 18,987 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,623) |  |  |  |
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Regency at Encino [Member] | Encino, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 460 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 27,870 |
Buildings and improvements |  |  |  | 111,482 |
Costs capitalized subsequent to acquisition |  |  |  | 3,165 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 27,870 |
Buildings and improvements |  |  |  | 114,647 |
Total | $ 142,517 |  |  | 142,517 |
Accumulated depreciation | $ (11,618) |  |  | (11,618) |
Date of construction | 2007 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 142,517 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,618) |  |  |  |
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Renaissance at Uptown Orange [Member] | Orange, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 438 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 25,073 |
Buildings and improvements |  |  |  | 121,314 |
Costs capitalized subsequent to acquisition |  |  |  | 854 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 25,073 |
Buildings and improvements |  |  |  | 122,168 |
Total | $ 147,241 |  |  | 147,241 |
Accumulated depreciation | $ (8,165) |  |  | (8,165) |
Date of construction | 2010 |  |  |  |
Date acquired | Apr-15 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 147,241 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,165) |  |  |  |
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Reveal [Member] | Woodland Hills, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 132 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,717 |
Buildings and improvements |  |  |  | 11,483 |
Costs capitalized subsequent to acquisition |  |  |  | 1,781 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,801 |
Buildings and improvements |  |  |  | 13,180 |
Total | $ 16,981 |  |  | 16,981 |
Accumulated depreciation | $ (7,106) |  |  | (7,106) |
Date of construction | 2000 |  |  |  |
Date acquired | Oct-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 16,981 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,106) |  |  |  |
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Salmon Run at Perry Creek [Member] | Bothell, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 153 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,324 |
Buildings and improvements |  |  |  | 7,501 |
Costs capitalized subsequent to acquisition |  |  |  | 6,497 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,331 |
Buildings and improvements |  |  |  | 13,991 |
Total | $ 17,322 |  |  | 17,322 |
Accumulated depreciation | $ (11,078) |  |  | (11,078) |
Date of construction | 1986 |  |  |  |
Date acquired | Nov-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 17,322 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,078) |  |  |  |
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Sammamish View [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 323 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,173 |
Buildings and improvements |  |  |  | 58,961 |
Costs capitalized subsequent to acquisition |  |  |  | 9,052 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,173 |
Buildings and improvements |  |  |  | 68,013 |
Total | $ 72,186 |  |  | 72,186 |
Accumulated depreciation | $ (16,920) |  |  | (16,920) |
Date of construction | 2001 |  |  |  |
Date acquired | Jul-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 72,186 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (16,920) |  |  |  |
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | 101 San Fernando [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 432 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 15,563 |
Buildings and improvements |  |  |  | 36,204 |
Costs capitalized subsequent to acquisition |  |  |  | 28,870 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 22,866 |
Buildings and improvements |  |  |  | 57,771 |
Total | $ 80,637 |  |  | 80,637 |
Accumulated depreciation | $ (26,023) |  |  | (26,023) |
Date of construction | 2003 |  |  |  |
Date acquired | Nov-03 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 80,637 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (26,023) |  |  |  |
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | San Marcos [Member] | Richmond, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 238 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 9,581 |
Buildings and improvements |  |  |  | 40,317 |
Costs capitalized subsequent to acquisition |  |  |  | 4,935 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 9,582 |
Buildings and improvements |  |  |  | 45,251 |
Total | $ 54,833 |  |  | 54,833 |
Accumulated depreciation | $ (10,633) |  |  | (10,633) |
Date of construction | 2004 |  |  |  |
Date acquired | Oct-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 54,833 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,633) |  |  |  |
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Santee Court/Santee Village [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 172 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,812 |
Buildings and improvements |  |  |  | 11,170 |
Costs capitalized subsequent to acquisition |  |  |  | 2,818 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,820 |
Buildings and improvements |  |  |  | 13,980 |
Total | $ 16,800 |  |  | 16,800 |
Accumulated depreciation | $ (6,781) |  |  | (6,781) |
Date of construction | 1983 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 16,800 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (6,781) |  |  |  |
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Shadow Point [Member] | Spring Valley, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 418 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 19,292 |
Buildings and improvements |  |  |  | 77,168 |
Costs capitalized subsequent to acquisition |  |  |  | 3,028 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 19,292 |
Buildings and improvements |  |  |  | 80,196 |
Total | $ 99,488 |  |  | 99,488 |
Accumulated depreciation | $ (8,197) |  |  | (8,197) |
Date of construction | 1986 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 99,488 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,197) |  |  |  |
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Shadowbrook [Member] | Redmond, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 108 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 7,379 |
Buildings and improvements |  |  |  | 22,138 |
Costs capitalized subsequent to acquisition |  |  |  | 540 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 7,379 |
Buildings and improvements |  |  |  | 22,678 |
Total | $ 30,057 |  |  | 30,057 |
Accumulated depreciation | $ (2,621) |  |  | (2,621) |
Date of construction | 2013 |  |  |  |
Date acquired | Sep-13 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 30,057 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,621) |  |  |  |
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Slater 116 [Member] | Kirkland, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 280 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 34,444 |
Buildings and improvements |  |  |  | 147,262 |
Costs capitalized subsequent to acquisition |  |  |  | 4,404 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 34,444 |
Buildings and improvements |  |  |  | 151,666 |
Total | $ 186,110 |  |  | 186,110 |
Accumulated depreciation | $ (17,915) |  |  | (17,915) |
Date of construction | 2014 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 186,110 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (17,915) |  |  |  |
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Solstice [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 196 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,167 |
Buildings and improvements |  |  |  | 12,603 |
Costs capitalized subsequent to acquisition |  |  |  | 5,889 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,201 |
Buildings and improvements |  |  |  | 18,458 |
Total | $ 21,659 |  |  | 21,659 |
Accumulated depreciation | $ (12,004) |  |  | (12,004) |
Date of construction | 1986 |  |  |  |
Date acquired | Oct-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 21,659 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,004) |  |  |  |
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Stonehedge Village [Member] | Bothell, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 300 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,959 |
Buildings and improvements |  |  |  | 23,670 |
Costs capitalized subsequent to acquisition |  |  |  | 5,523 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,977 |
Buildings and improvements |  |  |  | 29,175 |
Total | $ 35,152 |  |  | 35,152 |
Accumulated depreciation | $ (14,340) |  |  | (14,340) |
Date of construction | 1972 |  |  |  |
Date acquired | Dec-02 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 35,152 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (14,340) |  |  |  |
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Summit Park [Member] | San Diego, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 197 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,915 |
Buildings and improvements |  |  |  | 57,700 |
Costs capitalized subsequent to acquisition |  |  |  | 648 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,915 |
Buildings and improvements |  |  |  | 58,348 |
Total | $ 72,263 |  |  | 72,263 |
Accumulated depreciation | $ (5,840) |  |  | (5,840) |
Date of construction | 2008 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 72,263 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,840) |  |  |  |
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Taylor 28 [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Avery [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 121 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,964 |
Buildings and improvements |  |  |  | 29,922 |
Costs capitalized subsequent to acquisition |  |  |  | 105 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,964 |
Buildings and improvements |  |  |  | 30,027 |
Total | $ 36,991 |  |  | 36,991 |
Accumulated depreciation | $ (2,793) |  |  | (2,793) |
Date of construction | 2014 |  |  |  |
Date acquired | Mar-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 36,991 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,793) |  |  |  |
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 100 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,937 |
Buildings and improvements |  |  |  | 20,679 |
Costs capitalized subsequent to acquisition |  |  |  | 1,195 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,939 |
Buildings and improvements |  |  |  | 21,872 |
Total | $ 28,811 |  |  | 28,811 |
Accumulated depreciation | $ (7,191) |  |  | (7,191) |
Date of construction | 2006 |  |  |  |
Date acquired | Jun-07 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 28,811 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,191) |  |  |  |
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Cairns [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 264 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 12,555 |
Buildings and improvements |  |  |  | 29,307 |
Costs capitalized subsequent to acquisition |  |  |  | 5,378 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 12,556 |
Buildings and improvements |  |  |  | 34,684 |
Total | $ 47,240 |  |  | 47,240 |
Accumulated depreciation | $ (9,005) |  |  | (9,005) |
Date of construction | 1973 |  |  |  |
Date acquired | Jul-10 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 47,240 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,005) |  |  |  |
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Commons [Member] | Campbell, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 243 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,531 |
Buildings and improvements |  |  |  | 89,208 |
Costs capitalized subsequent to acquisition |  |  |  | 5,646 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,531 |
Buildings and improvements |  |  |  | 94,854 |
Total | $ 99,385 |  |  | 99,385 |
Accumulated depreciation | $ (27,586) |  |  | (27,586) |
Date of construction | 2009 |  |  |  |
Date acquired | Jan-09 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 99,385 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (27,586) |  |  |  |
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Grand [Member] | Oakland, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 292 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,202 |
Buildings and improvements |  |  |  | 4,794 |
Costs capitalized subsequent to acquisition |  |  |  | 51,281 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 8,385 |
Buildings and improvements |  |  |  | 49,892 |
Total | $ 58,277 |  |  | 58,277 |
Accumulated depreciation | $ (21,785) |  |  | (21,785) |
Date of construction | 1972 |  |  |  |
Date acquired | Apr-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 58,277 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (21,785) |  |  |  |
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Hallie [Member] | Pasadena, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 118 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 1,570 |
Buildings and improvements |  |  |  | 3,912 |
Costs capitalized subsequent to acquisition |  |  |  | 4,648 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 1,618 |
Buildings and improvements |  |  |  | 8,512 |
Total | $ 10,130 |  |  | 10,130 |
Accumulated depreciation | $ (4,933) |  |  | (4,933) |
Date of construction | 1971 |  |  |  |
Date acquired | Jun-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 10,130 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,933) |  |  |  |
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Lofts at Pinehurst [Member] | Ventura, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 188 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,574 |
Buildings and improvements |  |  |  | 54,298 |
Costs capitalized subsequent to acquisition |  |  |  | 1,857 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,574 |
Buildings and improvements |  |  |  | 56,155 |
Total | $ 69,729 |  |  | 69,729 |
Accumulated depreciation | $ (5,919) |  |  | (5,919) |
Date of construction | 2007 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 69,729 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,919) |  |  |  |
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Stuart [Member] | Pasadena, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 423 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 21,930 |
Buildings and improvements |  |  |  | 87,720 |
Costs capitalized subsequent to acquisition |  |  |  | 2,992 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 21,930 |
Buildings and improvements |  |  |  | 90,712 |
Total | $ 112,642 |  |  | 112,642 |
Accumulated depreciation | $ (9,312) |  |  | (9,312) |
Date of construction | 1985 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 112,642 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,312) |  |  |  |
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | The Trails of Redmond [Member] | Redmond, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 101 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,949 |
Buildings and improvements |  |  |  | 27,796 |
Costs capitalized subsequent to acquisition |  |  |  | 906 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,949 |
Buildings and improvements |  |  |  | 28,702 |
Total | $ 35,651 |  |  | 35,651 |
Accumulated depreciation | $ (2,902) |  |  | (2,902) |
Date of construction | 1987 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 35,651 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (2,902) |  |  |  |
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Tiffany Court [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 132 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 3,638 |
Buildings and improvements |  |  |  | 8,640 |
Costs capitalized subsequent to acquisition |  |  |  | 2,707 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 3,890 |
Buildings and improvements |  |  |  | 11,095 |
Total | $ 14,985 |  |  | 14,985 |
Accumulated depreciation | $ (7,091) |  |  | (7,091) |
Date of construction | 1985 |  |  |  |
Date acquired | Oct-97 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 14,985 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (7,091) |  |  |  |
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Trabucco Villas [Member] | Lake Forest, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 284 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 22,000 |
Buildings and improvements |  |  |  | 82,270 |
Costs capitalized subsequent to acquisition |  |  |  | 1,792 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 22,016 |
Buildings and improvements |  |  |  | 84,046 |
Total | $ 106,062 |  |  | 106,062 |
Accumulated depreciation | $ (19,028) |  |  | (19,028) |
Date of construction | 2011 |  |  |  |
Date acquired | Jul-11 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 106,062 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (19,028) |  |  |  |
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Via [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 272 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 13,842 |
Buildings and improvements |  |  |  | 55,367 |
Costs capitalized subsequent to acquisition |  |  |  | 3,627 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 13,842 |
Buildings and improvements |  |  |  | 58,994 |
Total | $ 72,836 |  |  | 72,836 |
Accumulated depreciation | $ (5,937) |  |  | (5,937) |
Date of construction | 1974 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 72,836 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (5,937) |  |  |  |
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Villa Siena [Member] | Costa Mesa, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 272 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 6,488 |
Buildings and improvements |  |  |  | 36,768 |
Costs capitalized subsequent to acquisition |  |  |  | 2,820 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 6,488 |
Buildings and improvements |  |  |  | 39,588 |
Total | $ 46,076 |  |  | 46,076 |
Accumulated depreciation | $ (4,132) |  |  | (4,132) |
Date of construction | 1971 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 46,076 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (4,132) |  |  |  |
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Village Green [Member] | La Habra, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 76 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,573 |
Buildings and improvements |  |  |  | 11,901 |
Costs capitalized subsequent to acquisition |  |  |  | 8,205 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,573 |
Buildings and improvements |  |  |  | 20,106 |
Total | $ 25,679 |  |  | 25,679 |
Accumulated depreciation | $ (8,793) |  |  | (8,793) |
Date of construction | 1963 |  |  |  |
Date acquired | Aug-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 25,679 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (8,793) |  |  |  |
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Vista Belvedere [Member] | Tiburon, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 58 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,545 |
Buildings and improvements |  |  |  | 16,635 |
Costs capitalized subsequent to acquisition |  |  |  | 79 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,545 |
Buildings and improvements |  |  |  | 16,714 |
Total | $ 22,259 |  |  | 22,259 |
Accumulated depreciation | $ (1,802) |  |  | (1,802) |
Date of construction | 2013 |  |  |  |
Date acquired | Oct-13 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 22,259 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (1,802) |  |  |  |
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Vox Apartments [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 163 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,858 |
Buildings and improvements |  |  |  | 19,168 |
Costs capitalized subsequent to acquisition |  |  |  | 4,269 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,887 |
Buildings and improvements |  |  |  | 23,408 |
Total | $ 28,295 |  |  | 28,295 |
Accumulated depreciation | $ (10,501) |  |  | (10,501) |
Date of construction | 1964 |  |  |  |
Date acquired | Oct-03 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 28,295 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,501) |  |  |  |
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Walnut Heights [Member] | Walnut, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 155 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,245 |
Buildings and improvements |  |  |  | 7,020 |
Costs capitalized subsequent to acquisition |  |  |  | 11,286 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,258 |
Buildings and improvements |  |  |  | 18,293 |
Total | $ 20,551 |  |  | 20,551 |
Accumulated depreciation | $ (11,308) |  |  | (11,308) |
Date of construction | 1990 |  |  |  |
Date acquired | Jun-94 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 20,551 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (11,308) |  |  |  |
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Wharfside Pointe [Member] | Seattle, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 508 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 43,194 |
Buildings and improvements |  |  |  | 101,030 |
Costs capitalized subsequent to acquisition |  |  |  | 9,603 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 43,194 |
Buildings and improvements |  |  |  | 110,633 |
Total | $ 153,827 |  |  | 153,827 |
Accumulated depreciation | $ (17,032) |  |  | (17,032) |
Date of construction | 1989 |  |  |  |
Date acquired | Oct-12 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 153,827 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (17,032) |  |  |  |
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Willow Lake [Member] | San Jose, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 284 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 30,535 |
Buildings and improvements |  |  |  | 91,604 |
Costs capitalized subsequent to acquisition |  |  |  | 1,004 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 30,535 |
Buildings and improvements |  |  |  | 92,608 |
Total | $ 123,143 |  |  | 123,143 |
Accumulated depreciation | $ (9,435) |  |  | (9,435) |
Date of construction | 2008 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 123,143 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (9,435) |  |  |  |
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | 5600 Wilshire [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 478 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 56,932 |
Buildings and improvements |  |  |  | 211,998 |
Costs capitalized subsequent to acquisition |  |  |  | 7,368 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 56,932 |
Buildings and improvements |  |  |  | 219,366 |
Total | $ 276,298 |  |  | 276,298 |
Accumulated depreciation | $ (25,646) |  |  | (25,646) |
Date of construction | 2014 |  |  |  |
Date acquired | Apr-14 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 276,298 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (25,646) |  |  |  |
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 5 years |  |  |  |
Unencumbered Apartment Communities [Member] | Wilshire La Brea [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 216 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 4,017 |
Buildings and improvements |  |  |  | 10,315 |
Costs capitalized subsequent to acquisition |  |  |  | 15,508 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,021 |
Buildings and improvements |  |  |  | 25,819 |
Total | $ 29,840 |  |  | 29,840 |
Accumulated depreciation | $ (17,389) |  |  | (17,389) |
Date of construction | 1989 |  |  |  |
Date acquired | Mar-89 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 29,840 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (17,389) |  |  |  |
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Windsor Ridge [Member] | Sunnyvale, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 302 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 2,040 |
Buildings and improvements |  |  |  | 8,727 |
Costs capitalized subsequent to acquisition |  |  |  | 22,031 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 2,044 |
Buildings and improvements |  |  |  | 30,754 |
Total | $ 32,798 |  |  | 32,798 |
Accumulated depreciation | $ (16,605) |  |  | (16,605) |
Date of construction | 1978 |  |  |  |
Date acquired | Mar-90 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 32,798 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (16,605) |  |  |  |
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Woodland Commons [Member] | Bellevue, WA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Units | apartment | 145 |  |  |  |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | 5,331 |
Buildings and improvements |  |  |  | 21,036 |
Costs capitalized subsequent to acquisition |  |  |  | 3,751 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 5,341 |
Buildings and improvements |  |  |  | 24,777 |
Total | $ 30,118 |  |  | 30,118 |
Accumulated depreciation | $ (10,673) |  |  | $ (10,673) |
Date of construction | 1987 |  |  |  |
Date acquired | Dec-04 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 30,118 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (10,673) |  |  |  |
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Unencumbered Apartment Communities [Member] | Woodside Village [Member] | Ventura, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Other Property [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Area of real estate property | ft² |  |  |  | 140,564 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | $ 13,279 |
Buildings and improvements |  |  |  | 26,115 |
Costs capitalized subsequent to acquisition |  |  |  | 4,063 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 14,508 |
Buildings and improvements |  |  |  | 28,949 |
Total | $ 43,457 |  |  | 43,457 |
Accumulated depreciation | (16,610) |  |  | $ (16,610) |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | 43,457 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | (16,610) |  |  |  |
Other Property [Member] | Hollywood [Member] | Los Angeles, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Area of real estate property | ft² |  |  |  | 34,000 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | $ 10,200 |
Buildings and improvements |  |  |  | 13,800 |
Costs capitalized subsequent to acquisition |  |  |  | 14 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 10,200 |
Buildings and improvements |  |  |  | 13,814 |
Total | 24,014 |  |  | 24,014 |
Accumulated depreciation | $ (3,934) |  |  | $ (3,934) |
Date of construction | 1938 |  |  |  |
Date acquired | Jul-06 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 24,014 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (3,934) |  |  |  |
Other Property [Member] | Hollywood [Member] | Los Angeles, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Other Property [Member] | Hollywood [Member] | Los Angeles, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member] |  |  |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |  |  |
Area of real estate property | ft² |  |  |  | 106,564 |
Initial cost [Abstract] |  |  |  |  |
Land |  |  |  | $ 3,079 |
Buildings and improvements |  |  |  | 12,315 |
Costs capitalized subsequent to acquisition |  |  |  | 4,049 |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Land and improvements |  |  |  | 4,308 |
Buildings and improvements |  |  |  | 15,135 |
Total | $ 19,443 |  |  | 19,443 |
Accumulated depreciation | $ (12,676) |  |  | (12,676) |
Date of construction | 1983 |  |  |  |
Date acquired | Jul-00 |  |  |  |
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at the end of year | $ 19,443 |  |  |  |
Reconciliation of Real Estate Accumulated Depreciation [Roll Forward] |  |  |  |  |
Balance at the end of year | $ (12,676) |  |  |  |
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member] | Minimum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 3 years |  |  |  |
Other Property [Member] | Derian Office Building [Member] | Irvine, CA [Member] | Maximum [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Life Used for Depreciation | 30 years |  |  |  |
Real Estate, Rental Property [Member] |  |  |  |  |
Gross amount carried at close of period [Abstract] |  |  |  |  |
Total | $ 12,331,469 | 11,244,681 | 5,443,757 | $ 12,676,306 | $ 11,244,681
Reconciliation of Carrying Amount of Real Estate Investments [Roll Forward] |  |  |  |  |
Balance at beginning of year | 12,331,469 | 11,244,681 | 5,443,757 |  |
Balance at the end of year | $ 12,676,306 | $ 12,331,469 | $ 11,244,681 |  |

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