Represents the amount of financing receivables recorded in other assets on the entity's balance sheet.

No definition available.

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- Definition

Represents the high end of the range of estimated fair value for investments in mortgage loans on real estate.

+ References

No definition available.

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- Definition

Represents the low end of the range of estimated fair value for investments in mortgage loans on real estate.

+ References

No definition available.

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- Definition

The impact of fair value adjustments on purchase price and it's impact on net income or loss for the period, gross.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification
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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

+ References

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

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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-Section S99
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-Subparagraph (SX 210.5-02.12)
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

No definition available.

+ Details

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The portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

No definition available.

+ Details

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- Definition

The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(c))
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- Definition

Amount of the contractual principal due at the origination of the mortgage loan (face amount).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
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-Subparagraph (SX 210.12-29)
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-Subparagraph (SX 210.5-04.(c) Schedule IV)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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Fair Value Measurements (Details) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
Fair Value Measurements (Details) - USD ($)	May 31, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Fair Value of Financial Instruments
Marketable securities		$ 28,570,000		$ 28,570,000		$ 28,579,000
Interest rate cap and swap agreements (included in other assets)		26,132,000		26,132,000		16,692,000
Purchase price and other fair value adjustments		11,149,000	$ 0	60,442,000	$ 0
Debt and preferred equity investments		2,168,515,000		2,168,515,000		2,114,041,000
Equity method investments		3,059,985,000		3,059,985,000		2,362,989,000
Additional amount of financing receivables included in other assets		89,600,000		89,600,000		65,500,000
Carrying Value
Fair Value of Financial Instruments
Debt and preferred equity investments		2,168,515,000		2,168,515,000		2,114,041,000
Fixed rate debt		3,765,899,000		3,765,899,000		4,305,165,000
Variable rate debt		2,137,000,000		2,137,000,000		1,605,431,000
Total		5,902,899,000		5,902,899,000		5,910,596,000
Fair Value
Fair Value of Financial Instruments
Marketable securities		28,570,000		28,570,000		28,579,000
Total		5,948,223,000		5,948,223,000		6,034,090,000
Estimated fair value of debt and preferred equity investments, low end of range		2,200,000,000		2,200,000,000		2,100,000,000
Estimated fair value of debt and preferred equity investments, high end of range		2,400,000,000		2,400,000,000		2,300,000,000
Level 1
Fair Value of Financial Instruments
Interest rate cap and swap agreements (included in other assets)		0		0		0
Level 2
Fair Value of Financial Instruments
Interest rate cap and swap agreements (included in other assets)		26,132,000		26,132,000		16,692,000
Level 3
Fair Value of Financial Instruments
Marketable securities		0		0		0
Interest rate cap and swap agreements (included in other assets)		0		0		0
Level 3 \| Fair Value
Fair Value of Financial Instruments
Fixed rate debt		3,796,225,000		3,796,225,000		4,421,866,000
Variable rate debt		2,151,998,000		2,151,998,000		1,612,224,000
Equity marketable securities \| Level 1
Fair Value of Financial Instruments
Marketable securities		0		0		0
Commercial mortgage-backed securities
Fair Value of Financial Instruments
Marketable securities		28,570,000		28,570,000		28,579,000
Commercial mortgage-backed securities \| Level 2
Fair Value of Financial Instruments
Marketable securities		28,570,000		28,570,000		28,579,000
Mezzanine/Jr. Mortgage Loan with an Initial Maturity Date of April 2017
Fair Value of Financial Instruments
Debt and preferred equity investments		250,500,000		250,500,000		0	$ 0
Total fixed rate \| Mezzanine/Jr. Mortgage Loan with an Initial Maturity Date of April 2017
Fair Value of Financial Instruments
Notes receivable		250,500,000		250,500,000
Accrued interest		7,700,000		7,700,000
Joint venture
Fair Value of Financial Instruments
Equity method investments		3,059,985,000		$ 3,059,985,000		$ 2,362,989,000
919 Third Avenue \| Joint venture \| 919 Third Avenue
Fair Value of Financial Instruments
Purchase price and other fair value adjustments		$ 49,300,000
2 Herald Square
Fair Value of Financial Instruments
Business combination, fair value adjustment	$ 11,100,000