Income from Participating Loan

No definition available.

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- Definition

Participating Loan, Interest Rate, Stated Percentage

+ References

No definition available.

+ Details

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- Definition

Participating Loan Years to Maturity

+ References

No definition available.

+ Details

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- Definition

Amount of gain on the sale of property that does not qualify for gain recognition as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 40

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.U.Q2)

-URI http://asc.fasb.org/extlink&oid=6955272&loc=d3e221323-122791

+ Details

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Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

+ Details

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570

+ Details

Name:	us-gaap_EquityMethodInvestments
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

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Joint Ventures (Details) (USD $)	12 Months Ended
Joint Ventures (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2014 Communities	Sep. 30, 2014 Land_Parcels	Jun. 30, 2013
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	$ 718,226,000us-gaap_EquityMethodInvestments	$ 507,655,000us-gaap_EquityMethodInvestments
Deferred Gain on Sale of Property	24,683,000us-gaap_DeferredGainOnSaleOfProperty	25,400,000us-gaap_DeferredGainOnSaleOfProperty
MetLife I
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	13,306,000	47,497,000
MetLife I \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	4			6
Number of Units in Real Estate Property	0
Investment in and advances to unconsolidated joint ventures, net	13,306,000	47,497,000
Equity method investment, ownership percent	15.70%	4.50%
MetLife I \| Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Equity method investment, ownership percent	5.00%
MetLife II
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	431,277,000	327,926,000
MetLife II \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	21
Number of Units in Real Estate Property	4,642
Investment in and advances to unconsolidated joint ventures, net	431,277,000	327,926,000
Equity method investment, ownership percent	50.00%	50.00%
MetLife II \| Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties					2
Equity method investment, ownership percent					50.10%
Unconsolidated Joint Venture Other MetLife [Member] \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	1
Number of Units in Real Estate Property	1,282
Investment in and advances to unconsolidated joint ventures, net	134,939,000	36,313,000
Equity method investment, ownership percent	50.60%	35.80%
Unconsolidated Joint Venture Other MetLife [Member] \| Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Unconsolidated Joint Venture Other MetLife [Member] \| Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	2
Unconsolidated Joint Venture Vitruvian Park [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	80,302,000	79,318,000
Equity method investment, ownership percent		50.00%				50.00%
Deferred Gain on Sale of Property		436,000
Unconsolidated Joint Venture Vitruvian Park [Member] \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3	2
Number of Units in Real Estate Property	1,394
Investment in and advances to unconsolidated joint ventures, net	80,302,000	79,318,000
Equity method investment, ownership percent	50.00%	50.00%
Unconsolidated Joint Venture Vitruvian Park [Member] \| Land Parcel
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	6
Unconsolidated Joint Venture 399 Fremont [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net		31,100,000
Equity method investment, ownership percent		49.00%
Unconsolidated Joint Venture 399 Fremont [Member] \| Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Units in Real Estate Property		447
Lodge at Stoughton
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percent		95.00%
KFH
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	21,596,000	25,919,000
Equity method investment, ownership percent	30.00%
KFH \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	3
Number of Units in Real Estate Property	660
Investment in and advances to unconsolidated joint ventures, net	21,596,000	25,919,000
Equity method investment, ownership percent	30.00%	30.00%
Texas JV
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	(25,901,000)	(23,591,000)
Deferred Gain on Sale of Property	23,900,000	24,000,000
Texas JV \| Operating Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Real Estate Properties	8		10
Number of Units in Real Estate Property	3,359
Investment in and advances to unconsolidated joint ventures, net	(25,901,000)	(23,591,000)
Equity method investment, ownership percent	20.00%	20.00%
399 Fremont
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net			55,500,000
Unconsolidated Joint Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Investment in and advances to unconsolidated joint ventures, net	655,519,000	493,382,000
Participating Loan Investment Steele Creek Denver Colorado [Member]
Schedule of Equity Method Investments [Line Items]
Income from Participating Loan	156,000
Participating Loan Investment Steele Creek Denver Colorado [Member] \| Development Community [Member]
Schedule of Equity Method Investments [Line Items]
Number of Units in Real Estate Property	218
Investment in and advances to unconsolidated joint ventures, net	62,707,000	14,273,000
Participating Loan, Interest Rate, Stated Percentage	6.50%
Participating Loan Years to Maturity	2 years 10 months 0 days
Income from Participating Loan	$ 2,350,000	$ 156,000	$ 0