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 difference between the book value and the sale price of land parcels sold within the period.

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No definition available.

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Represents the purchase price of land acquired in a joint venture.

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No definition available.

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Carrying amount of equity interests owned by noncontrolling partners in partially owned properties.

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No definition available.

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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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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities.

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Amount of assets acquired at the acquisition date.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Real Estate and Lease Intangibles - Additional Information (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Oct. 14, 2016 USD ($) $ / shares	Mar. 10, 2016 USD ($) $ / shares	Dec. 31, 2017 USD ($) Property $ / shares	Dec. 31, 2016 USD ($) Property $ / shares	Dec. 31, 2015 USD ($) $ / shares
Real Estate [Line Items]
Net gain on sales of real estate properties			$ 157,057	$ 4,044,055	$ 335,134
Net gain (loss) on sales of land parcels			$ 19,167	$ 15,731	$ (1)
Properties disposed \| Property			5	99
Property Units disposed \| Property			1,194	29,776
Sales Price			$ 388,400	$ 6,943,458
Distributions declared per common share outstanding \| $ / shares			$ 2.015	$ 13.015	$ 2.21
Non-cash asset impairment charge			$ 1,700
Real estate held-for-sale, value			200
Business combination, recognized identifiable assets acquired and liabilities assumed, assets			468,050	$ 249,334
Investment in real estate, net			19,986,518	20,026,036
Noncontrolling interests partially owned properties			4,708	10,609
Deposits - restricted			50,115	141,881	$ 112,839
Company's Portion [Member]
Real Estate [Line Items]
Land purchase price			76,100
Business combination, recognized identifiable assets acquired and liabilities assumed, assets			102,500
Investment in real estate, net			0
Noncontrolling interests partially owned properties			0
Accrued liabilities			0
Deposits - restricted			0
Joint Venture Partner [Member]
Real Estate [Line Items]
Land purchase price			57,900
Business combination, recognized identifiable assets acquired and liabilities assumed, assets			75,700
Investment in real estate, net			116,700
Noncontrolling interests partially owned properties			117,300
Accrued liabilities			1,100
Deposits - restricted			1,700
Partially Owned Properties – Unconsolidated
Real Estate [Line Items]
Net gain on sales of real estate properties				$ 8,900
Properties disposed \| Property				1
Property Units disposed \| Property				336
Sales Price				$ 74,500
Investment in real estate, net			316,187
Noncontrolling interests partially owned properties			137,152
Deposits - restricted			$ 258
Starwood Portfolio [Member]
Real Estate [Line Items]
Net gain on sales of real estate properties				$ 3,200,000
Properties disposed \| Property				72
Property Units disposed \| Property				23,262
Sales Price				$ 5,365,000
Distributions declared per common share outstanding \| $ / shares	$ 3.00	$ 8.00	$ 0	$ 11.00	$ 0
Payments of dividends	$ 1,100,000	$ 3,000,000