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Schedule III Real Estate and Accumulated Depreciation (Parenthetical) (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 USD ($) Contract | Dec. 31, 2015 | Sep. 30, 2016 USD ($)
Real Estate and Accumulated Depreciation [Line Items] |  |  |
SEC Schedule III, Real Estate, Federal Income Tax Basis | $ 10,450,000,000 |  |
Finite-Lived Intangible Assets, Remaining Amortization Period | 6 months |  |
Encumbrance 1 | FNMA |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Secured credit facilities, amount available | $ 160,000,000 |  |
Line of credit facility, amount outstanding | $ 160,000,000 |  |
Variable interest rate (percent) | 1.10% |  |
Encumbrance 1 | FNMA | Interest Rate Swap |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Number of Interest rate derivatives held (contracts) | Contract | 2 |  |
Variable rate borrowings after interest rate swaps (percent) | 4.50% |  |
Encumbrance 1 | FNMA | Interest Rate Cap |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Derivative, Notional Amount | $ 50,000,000 |  |
Encumbrance 2 | Fixed Rate Debt | Loan [Member] |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Amount of bond used as encumbrance | $ 127,000,000 |  |
Derivative, Notional Amount |  |  | $ 128,000,000
Derivative cap interest rate (percent) | 4.50% |  |
Derivative termination date | Jun. 10, 2021 |  |
Furniture, fixtures and equipment |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Estimated useful lives (years) | 5 years |  |
Minimum | Land improvements and buildings |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Estimated useful lives (years) | 8 years |  |
Maximum | Land improvements and buildings |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Estimated useful lives (years) | 40 years |  |
Corporate Real Estate Owned | Minimum |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Real Estate and Accumulated Depreciation, Life Used for Depreciation |  | 1 year |
Corporate Real Estate Owned | Maximum |  |  |
Real Estate and Accumulated Depreciation [Line Items] |  |  |
Real Estate and Accumulated Depreciation, Life Used for Depreciation |  | 40 years |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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