Line of Credit Facility, Basis Point Fee

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- Definition

Line of Credit Facility, Threshold Amount for Basis Point Fee

+ References

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- Definition

Secured Debt, Amount Transferred to Liabilities Related to Net Assets Held for Sale

+ References

No definition available.

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- Definition

Represents the carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations and other loans payable.

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The portion of the carrying amount of long-term secured loans 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 aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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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.

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No definition available.

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- Definition

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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No definition available.

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Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The interest rate applicable to 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

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- Definition

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (12)(c)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

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-Subparagraph (16)(c)

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-Name Accounting Standards Codification

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-Subparagraph 14

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

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-Section S99

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-Subparagraph (SX 210.7-03.16)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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- Definition

The per share liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.27(b))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 28

-Subparagraph b

-Article 5

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Mortgages and Other Loans Payable (Details) - USD ($)		9 Months Ended
Mortgages and Other Loans Payable (Details) - USD ($)	Sep. 30, 2015	Sep. 30, 2015	Feb. 28, 2015	Jan. 31, 2015	Dec. 31, 2014	Oct. 31, 2014
Debt Instrument [Line Items]
Total fixed rate debt	$ 5,824,875,000	$ 5,824,875,000			$ 4,736,709,000
Total floating rate debt	1,040,508,000	1,040,508,000			1,103,942,000
Total fixed rate and floating rate debt	6,865,383,000	6,865,383,000			5,840,651,000
Mortgages reclassed to liabilities related to assets held for sale	0	0			(253,942,000)
Total mortgages and other loans payable	6,865,383,000	6,865,383,000			5,586,709,000
Federal Home Loan Bank Advances outstanding	$ 6,000,000	$ 6,000,000
Federal Home Loan Bank, advances, weighted-average borrowing rate (as a percent)	0.52%	0.52%
Book value of collateral	$ 10,500,000,000	$ 10,500,000,000			8,200,000,000
Series J Preferred Stock
Debt Instrument [Line Items]
Total fixed rate debt	4,000,000	4,000,000			4,000,000
Temporary Equity, Carrying Amount, Attributable to Noncontrolling Interest	$ 4,000,000	$ 4,000,000
Preferred units, shares outstanding	4,000	4,000
Preferred Units (as a percent)		3.75%
Preferred Units, liquidation preference (in dollars per unit)	$ 1,000.00	$ 1,000.00
FHLB Facility
Debt Instrument [Line Items]
Total fixed rate debt	$ 1,000,000	$ 1,000,000			0
Total floating rate debt	5,000,000	5,000,000			0
Master Repurchase Agreement
Debt Instrument [Line Items]
Total floating rate debt	285,508,000	285,508,000			100,000,000
Maximum facility capacity	$ 300,000,000.0	300,000,000.0
Basis Point Fee (as a percent)	0.25%
Threshold amount for basis point fee to be applicable (less than)	$ 150,000,000.0
500 West Putnam Avenue
Debt Instrument [Line Items]
Total fixed rate debt	22,527,000	22,527,000			22,968,000
Landmark Square
Debt Instrument [Line Items]
Total fixed rate debt	79,995,000	79,995,000			81,269,000
485 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt	450,000,000	450,000,000			450,000,000
762 Madison Avenue
Debt Instrument [Line Items]
Total fixed rate debt	7,916,000	7,916,000			8,045,000
885 Third Avenue
Debt Instrument [Line Items]
Total fixed rate debt	267,650,000	267,650,000			267,650,000
1745 Broadway
Debt Instrument [Line Items]
Total fixed rate debt	16,000,000	16,000,000			16,000,000
388-390 Greenwich Street
Debt Instrument [Line Items]
Total fixed rate debt	1,004,000,000	1,004,000,000			1,004,000,000
Total floating rate debt	446,000,000	446,000,000			446,000,000
388-390 Greenwich Street \| Swap One
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						3.80%
Total fixed rate debt						$ 504,000,000
388-390 Greenwich Street \| Swap Two
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						2.69%
Total fixed rate debt						$ 500,000,000
One Madison Avenue
Debt Instrument [Line Items]
Total fixed rate debt	548,699,000	548,699,000			565,742,000
100 Church Street
Debt Instrument [Line Items]
Total fixed rate debt	226,000,000	226,000,000			228,612,000
919 Third Avenue
Debt Instrument [Line Items]
Total fixed rate debt	$ 500,000,000	$ 500,000,000			500,000,000
Interest in property (as a percent)	51.00%	51.00%
400 East 57th Street
Debt Instrument [Line Items]
Total fixed rate debt	$ 67,962,000	$ 67,962,000			68,896,000
400 East 58th Street
Debt Instrument [Line Items]
Total fixed rate debt	29,126,000	29,126,000			29,527,000
420 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt	300,000,000	300,000,000			300,000,000
1515 Broadway
Debt Instrument [Line Items]
Total fixed rate debt	900,000,000	900,000,000			900,000,000
11 Madison Avenue
Debt Instrument [Line Items]
Total fixed rate debt	1,400,000,000	1,400,000,000			0
711 Third Avenue
Debt Instrument [Line Items]
Total fixed rate debt	0	0			120,000,000
120 West 45th Street
Debt Instrument [Line Items]
Total fixed rate debt	0	0			170,000,000
248-252 Bedford Avenue
Debt Instrument [Line Items]
Total floating rate debt	29,000,000	29,000,000			29,000,000
220 East 42nd Street
Debt Instrument [Line Items]
Total floating rate debt	275,000,000	275,000,000			275,000,000
180 Maiden Lane
Debt Instrument [Line Items]
Total floating rate debt	$ 0	$ 0			$ 253,942,000
Weighted Average \| Series J Preferred Stock
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.75%	3.75%
Weighted Average \| FHLB Facility
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	0.46%	0.46%
Interest rate, floating rate debt (as a percent)	0.53%	0.53%
Weighted Average \| Master Repurchase Agreement
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	3.35%	3.35%
Weighted Average \| 500 West Putnam Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.52%	5.52%
Weighted Average \| Landmark Square
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.00%	4.00%
Weighted Average \| 485 Lexington Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.61%	5.61%
Weighted Average \| 762 Madison Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.86%	3.86%	3.86%	3.75%
Weighted Average \| 885 Third Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	6.26%	6.26%
Weighted Average \| 1745 Broadway
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.81%	4.81%
Weighted Average \| 388-390 Greenwich Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.25%	3.25%
Interest rate, floating rate debt (as a percent)	1.94%	1.94%
Weighted Average \| One Madison Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.91%	5.91%
Weighted Average \| 100 Church Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.68%	4.68%
Weighted Average \| 919 Third Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	5.12%	5.12%
Weighted Average \| 400 East 57th Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.13%	4.13%
Weighted Average \| 400 East 58th Street
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	4.13%	4.13%
Weighted Average \| 420 Lexington Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.99%	3.99%
Weighted Average \| 1515 Broadway
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.93%	3.93%
Weighted Average \| 11 Madison Avenue
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	3.84%	3.84%
Weighted Average \| 248-252 Bedford Avenue
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	1.70%	1.70%
Weighted Average \| 220 East 42nd Street
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)	1.80%	1.80%
LIBOR \| Minimum \| Master Repurchase Agreement
Debt Instrument [Line Items]
Credit facility, interest rate (as a percent)		2.50%
LIBOR \| Maximum \| Master Repurchase Agreement
Debt Instrument [Line Items]
Credit facility, interest rate (as a percent)		3.25%