The total number of rental properties that the Company disposed of to unaffiliated parties during the period.

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Total number of rental units associated with rental properties that the company disposed of to unaffiliated third parties during the period.

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No definition available.

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The aggregate liquidation preference of preferred interests acquired in conjunction with the Archstone transaction.

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The percentage rate used to calculate dividend payments on preferred shares/preference units.

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No definition available.

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Represents charges to interest expense related to the extinguishment of borrowing before maturity.

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The cash inflow from the sale of real estate investment property.

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No definition available.

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Redemption of Series P Preference Units

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral.

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No definition available.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Fair value of liability arising from contracts that meet the criteria of being accounted for as derivative instruments, financial instrument or contract used to mitigate a specified risk (hedge), energy marketing activities (trading activities), expected to be settled after one year or beyond the normal operating cycle, if longer. Examples of energy marketing activities include, but are not limited to, trading of electricity, coal, natural gas and oil using financial instruments, including, but not limited to, forward contracts, options and swaps.

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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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No definition available.

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Amount of liabilities classified as other.

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The cash outflow or inflow for a financial contract that meets the hedge criteria as either a cash flow hedge, fair value hedge, or hedge of a net investment in a foreign operation.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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No definition available.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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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