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Organization and Summary of Significant Accounting Policies (Textual) (Details) $ / shares in Units, ft² in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 USD ($) $ / shares | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2017 shares | Dec. 31, 2017 | Dec. 31, 2017 Property | Dec. 31, 2017 Communities | Dec. 31, 2017 ft² | Dec. 01, 2016 shares
Real Estate Properties |  |  |  |  |  |  |  |  |  |
General partners' capital account, units outstanding | shares |  | 113,518,212 |  |  | 113,643,166 |  |  |  |  |
Limited Liability (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest | 96.40% |  |  |  |  |  |  |  |  |
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest |  | 96.40% |  |  |  |  |  |  |  |
Number of Real Estate Properties |  |  |  |  |  |  | 302 | 301 |  |
Advertising expenses | $ 18,800,000 | $ 13,000,000 | $ 13,500,000 |  |  |  |  |  |  |
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months |  |  |  | $ 2,800,000 |  |  |  |  |  |
Finite-Lived Intangible Assets, Amortization Expense, Year Three |  |  |  | 1,600,000 |  |  |  |  |  |
Finite-Lived Intangible Assets, Amortization Expense, Year Four |  |  |  | 800,000 |  |  |  |  |  |
Finite-Lived Intangible Assets, Amortization Expense, Year Five |  |  |  | 500,000 |  |  |  |  |  |
Finite-Lived Intangible Assets, Amortization Expense, after Year Five |  |  |  | 300,000 |  |  |  |  |  |
Preferred Stock, Redemption Price Per Share | $ / shares | $ 50.00 |  |  |  |  |  |  |  |  |
Acquisition Costs, Period Cost | $ 1,300,000 |  |  |  |  |  |  |  |  |
Leases, Acquired-in-Place |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Amortization period of in-place leases and residential relationships (months) | 6 months |  |  |  |  |  |  |  |  |
Lease Intangibles, Gross |  | 42,400,000 |  | 11,200,000 |  |  |  |  |  |
Accumulated amortization |  | 7,300,000 |  | 4,100,000 |  |  |  |  |  |
Depreciation and amortization | $ 29,400,000 | 8,700,000 | 5,000,000 |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) |  |  |  |  |  | 92.50% |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) |  |  |  |  |  | 100.00% |  |  |  |
Maximum self insurance reserve for workers' compensation claims |  |  |  | 500,000 |  |  |  |  |  |
Development Properties |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties | Communities |  |  |  |  |  |  |  | 3 |  |
Number of units under development community | Property |  |  |  |  |  |  | 937 |  |  |
Number of units in real estate property | Property |  |  |  |  |  |  | 240 |  |  |
Development Properties | Expected Costs |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Development and capital improvements in progress |  |  |  | 214,000,000 |  |  |  |  |  |
Development Properties | Costs Incurred to Date |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Development and capital improvements in progress |  |  |  | 167,700,000 |  |  |  |  |  |
Retail |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties | Property |  |  |  |  |  |  | 29 |  |  |
Square footage of real estate property (square foot) | ft² |  |  |  |  |  |  |  |  | 620 |
Commercial Properties |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Number of Real Estate Properties | Property |  |  |  |  |  |  | 4 |  |  |
Square footage of real estate property (square foot) | ft² |  |  |  |  |  |  |  |  | 230 |
Colonial Grand at McKinney |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  | 35.00% |  |  |  |
Real Estate Investments, Joint Ventures |  |  |  | 45,000,000 |  |  |  |  |  |
Real Estate Technology Ventures, L.P. [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Equity Method Investment, Ownership Percentage |  |  |  |  |  | 31.00% |  |  |  |
Real Estate Investments, Joint Ventures |  |  |  | 1,500,000 |  |  |  |  |  |
Real Estate Technology Ventures, L.P. [Member] | Limited Partner Capital Contribution, Future Obligation [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Real Estate Investments, Joint Ventures |  |  |  | 13,500,000 |  |  |  |  |  |
Post River North [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Number of units in real estate property |  |  |  |  |  | 359 |  |  |  |
Development and capital improvements in progress |  |  |  | 0 |  |  |  |  |  |
Buildings, Improvements, and Other |  |  |  | 33,900,000 |  |  |  |  |  |
Percentage of ownership interests of all consolidated subsidiaries (percent) |  |  |  |  |  | 92.50% |  |  |  |
Land |  |  |  | 0 |  |  |  |  |  |
Accrued Liabilities |  |  |  | 0 |  |  |  |  |  |
Parent Company [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Capitalized Development Costs, Period | $ 11,000,000 | $ 2,700,000 | 2,300,000 |  |  |  |  |  |  |
Preferred Stock, Shares Outstanding | shares |  | 867,846 |  |  | 867,846 |  |  |  |  |
Development and capital improvements in progress |  | $ 231,224,000 |  | 116,833,000 |  |  |  |  |  |
Buildings, Improvements, and Other |  | 10,853,474,000 |  | 11,281,504,000 |  |  |  |  |  |
Common Stock, Conversion Basis | 0.71 |  |  |  |  |  |  |  |  |
Total interest capitalized during period | $ 7,238,000 | 2,073,000 | 1,655,000 |  |  |  |  |  |  |
Lease Intangibles, Gross |  | 12,900,706,000 |  | 13,234,754,000 |  |  |  |  |  |
Accumulated amortization |  | 1,674,801,000 |  | 2,075,071,000 |  |  |  |  |  |
Depreciation and amortization | 493,708,000 | 322,958,000 | 294,520,000 |  |  |  |  |  |  |
Land |  | 1,816,008,000 |  | 1,836,417,000 |  |  |  |  |  |
Accrued Liabilities |  | 452,605,000 |  | 405,560,000 |  |  |  |  |  |
Parent Company [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Maximum self insurance reserve for general liability claims |  |  |  | 100,000 |  |  |  |  |  |
Accrued Liabilities [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Dividends Payable |  | 102,400,000 |  | 108,700,000 |  |  |  |  |  |
Accrued Real Estate Taxes |  | 97,600,000 |  | 99,600,000 |  |  |  |  |  |
Unearned Income | 40,800,000 | 39,400,000 |  |  |  |  |  |  |  |
Loss Contingency, Loss in Period | $ 32,100,000 | 42,100,000 |  |  |  |  |  |  |  |
Security Deposit Liability |  | 18,800,000 |  | 19,100,000 |  |  |  |  |  |
Interest Payable |  | $ 19,100,000 |  | 18,100,000 |  |  |  |  |  |
Limited Partner [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
General partners' capital account, units outstanding | shares |  | 113,518,212 |  |  | 113,643,166 |  |  |  |  |
Development and capital improvements in progress |  | $ 231,224,000 |  | 116,833,000 |  |  |  |  |  |
Buildings, Improvements, and Other |  | 10,853,474,000 |  | 11,281,504,000 |  |  |  |  |  |
Common Unit, Conversion Basis | 0.71 |  |  |  |  |  |  |  |  |
Total interest capitalized during period | $ 7,238,000 | 2,073,000 | 1,655,000 |  |  |  |  |  |  |
Lease Intangibles, Gross |  | 12,900,706,000 |  | 13,234,754,000 |  |  |  |  |  |
Accumulated amortization |  | 1,674,801,000 |  | 2,075,071,000 |  |  |  |  |  |
Depreciation and amortization | $ 493,708,000 | 322,958,000 | $ 294,520,000 |  |  |  |  |  |  |
Land |  | 1,816,008,000 |  | 1,836,417,000 |  |  |  |  |  |
Accrued Liabilities |  | $ 452,605,000 |  | $ 405,560,000 |  |  |  |  |  |
Redeemable Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Real Estate Properties |  |  |  |  |  |  |  |  |  |
Preferred Stock, Shares Outstanding | shares |  |  |  |  |  |  |  |  |  | 867,846

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