XML 140 R120.htm IDEA: XBRL DOCUMENT
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Subsequent Events/Other - Additional Information (Details) $ in Thousands | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Feb. 22, 2018 USD ($) Property ApartmentUnit | Dec. 31, 2017 USD ($) Property | Dec. 31, 2016 USD ($) Property ApartmentUnit | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Aug. 31, 2017 USD ($)
Subsequent Event [Line Items] |  |  |  |  |  |
Properties disposed | Property |  | 5 | 99 |  |  |
Disposed Units | Property |  | 1,194 | 29,776 |  |  |
Proceeds from sale of property |  | $ 388,400 | $ 6,943,458 |  |  |
Repayment of mortgage debt |  | $ 10,704 | 8,544 | $ 9,275 |  |
Debt instrument, maturity date |  | Jan. 10, 2022 |  |  |  |
Other liabilities |  | $ 341,852 | 350,466 |  |  |
Interest and other income |  | 6,136 | $ 65,773 | $ 7,372 |  |
Military Housing [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Disposed Units | ApartmentUnit |  |  | 5,161 |  |  |
Proceeds from sale of property |  |  | $ 63,300 |  |  |
Interest and other income |  |  | 52,400 |  |  |
Series P [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Preferred Stock Preference Units Dividend Rate Percentage |  |  |  |  | 3.00% |
Liquidation Value Preferred Interests |  |  |  |  | $ 18,400 |
Business acquisition, percentage of voting interests acquired |  |  |  |  | 95.00% |
Redemption of series P preference units |  |  | 18,400 |  |  |
Other liabilities |  |  | 18,400 |  |  |
Mortgages [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Write off of deferred debt issuance cost |  | $ 300 | $ 1,600 |  |  |
Debt instrument, maturity date |  | May 28, 2061 | May 28, 2061 |  |  |
Forward Starting Swaps [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Public notes, face value |  |  |  |  |  | $ 400,000
Subsequent Event [Member] | 6.08% Mortgage Debt [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Repayment of mortgage debt | $ 550,000 |  |  |  |  |
Prepayment penalty charges | 22,100 |  |  |  |  |
Subsequent Event [Member] | 5.75% Mortgage Debt [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Repayment of mortgage debt | $ 43,400 |  |  |  |  |
Subsequent Event [Member] | Mortgages [Member] | 6.08% Mortgage Debt [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Debt instrument, interest rate, stated percentage | 6.08% |  |  |  |  |
Write off of deferred debt issuance cost | $ 400 |  |  |  |  |
Debt instrument, maturity date | Mar. 01, 2020 |  |  |  |  |
Subsequent Event [Member] | Mortgages [Member] | 5.75% Mortgage Debt [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Debt instrument, interest rate, stated percentage | 5.75% |  |  |  |  |
Debt instrument, maturity date | Apr. 01, 2018 |  |  |  |  |
Subsequent Event [Member] | 3.50% Notes [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Debt instrument, interest rate, stated percentage | 3.50% |  |  |  |  |
Public notes, face value | $ 500,000 |  |  |  |  |
Proceeds from debt, net of issuance costs | $ 497,000 |  |  |  |  |
Debt instrument, interest rate, effective percentage | 3.61% |  |  |  |  |
Subsequent Event [Member] | Forward Starting Swaps [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Secured or unsecured debt issuances | $ 250,000 |  |  |  |  |
Payments for (proceeds from) hedge, investing activities | $ 1,600 |  |  |  |  |
Subsequent Event [Member] | PARTIALLY OWNED PROPERTIES [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Properties disposed | Property | 2 |  |  |  |  |
Disposed Units | ApartmentUnit | 331 |  |  |  |  |
Proceeds from sale of property | $ 113,000 |  |  |  |  |

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