Real Estate Starwood Disposition (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) property $ / shares	Mar. 31, 2015 $ / shares	Dec. 31, 2015 USD ($)
Disposed Properties \| property	80
Apartment Units	26,162
Sales Price	$ 6,342,408
Earnest money on pending acquisitions	0		$ 1,000
Land	5,777,206		5,864,046
Depreciable property Abstract
Buildings and improvements	16,430,979		16,346,829
Furniture, fixtures and equipment	1,219,444		1,207,098
In-Place lease intangibles	179,511		179,511
Investment in real estate	25,120,866		25,182,352
Accumulated depreciation	(4,977,274)		(4,905,406)
Real estate held for sale	$ 0		$ 2,181,135
Common Stock, Dividends, Per Share, Declared \| $ / shares	$ 8.50375	$ 0.5525
Starwood Portfolio [Member]
Disposed Properties \| property	72
Apartment Units	23,262
Sales Price	$ 5,365,000
Earnest money on pending acquisitions	250,000
Land	602,737
Depreciable property Abstract
Buildings and improvements	2,386,489
Furniture, fixtures and equipment	335,565
In-Place lease intangibles	35,554
Investment in real estate	3,360,345
Accumulated depreciation	(1,179,210)
Real estate held for sale	$ 2,181,135
Common Stock, Dividends, Per Share, Declared \| $ / shares	$ 8.00
Payments of Dividends	$ 3,000,000
Rental Properties – Consolidated (1)
Disposed Properties \| property	80
Apartment Units	26,162
Sales Price	$ 6,314,953
Rental Properties – Consolidated (1) \| Starwood Portfolio [Member]
Disposed Properties \| property	72
Apartment Units	23,262
South Florida \| Starwood Portfolio [Member]
Disposed Properties \| property	33
Apartment Units	10,742
Denver \| Starwood Portfolio [Member]
Disposed Properties \| property	18
Apartment Units	6,635
Washington D.C. \| Starwood Portfolio [Member]
Disposed Properties \| property	10
Apartment Units	3,020
Seattle \| Starwood Portfolio [Member]
Disposed Properties \| property	8
Apartment Units	1,721
Inland Empire, CA (part of Los Angeles) \| Starwood Portfolio [Member]
Disposed Properties \| property	3
Apartment Units	1,144

Depreciable property.

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

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No definition available.

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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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- Definition

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

+ References

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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A deposit made by a purchaser of real estate to evidence good faith. It is customary for a buyer to give the seller earnest money at the time a sales contract is signed. The earnest money generally is credited to the down payment at closing, which is applied at closing as a component of payment against the purchase price.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Amount before accumulated depreciation of fixtures and equipment. Includes, but is not limited to, machinery, equipment, and engines.

+ References

No definition available.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
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The cumulative amount of depreciation for real estate property held for investment purposes.

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-Name Accounting Standards Codification
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Amount of real estate investment property 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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