Debt Instrument, Extension Option Exercised, Term

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- Definition

Debt Instrument, Number of Extension Options

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- Definition

Debt Instrument, Period of Extension Option

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- Definition

Disposal Group Including Discontinued Operation Deconsolidation Of Ownership Interest Percentage

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- Definition

Disposal Group Including Discontinued Operation, Ownership Percentage in Disposed Asset

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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.

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- Definition

Secured Debt, Bearing Fixed Interest, Mortgage Amount

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- Definition

Secured Debt, Bearing Fixed Interest, Subordinate Loan Amount

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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.

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- Definition

Secured Debt, Gross

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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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.

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-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

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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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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount of advances from the Federal Home Loan Bank (FHLB).

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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Mortgages and Other Loans Payable (Details)		1 Months Ended		12 Months Ended
Mortgages and Other Loans Payable (Details)	Jan. 21, 2021	Jun. 30, 2020	Aug. 31, 2019	Dec. 31, 2020 USD ($) extension	Jan. 31, 2020	Dec. 31, 2019 USD ($)	Apr. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)
Debt Instrument [Line Items]
Total fixed rate debt				$ 1,083,683,000		$ 1,383,449,000
Total floating rate debt				917,677,000		828,434,000
Total mortgages and other loans payable				2,001,360,000		2,211,883,000
Deferred financing costs, net of amortization				(21,388,000)		(28,630,000)
Total mortgages and other loans payable				1,979,972,000		2,183,253,000
Book value of collateral				2,500,000,000		3,300,000,000
Outstanding under line of credit facility				105,262,000		234,013,000
762 Madison Avenue
Debt Instrument [Line Items]
Interest acquired					10.00%
FHLB Facility, January 2021, 1
Debt Instrument [Line Items]
Total floating rate debt				$ 10,000,000		0
FHLB Facility, January 2021, 1 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				0.28%
FHLB Facility, January 2021, 2
Debt Instrument [Line Items]
Total floating rate debt				$ 15,000,000		0
FHLB Facility, January 2021, 2 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				0.23%
FHLB Facility January 2021
Debt Instrument [Line Items]
Total floating rate debt				$ 35,000,000		0
FHLB Facility January 2021 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				0.18%
2017 Master Repurchase Agreement 2017
Debt Instrument [Line Items]
Total floating rate debt				$ 0		152,684,000
Maximum facility capacity				$ 400,000,000.0			$ 400,000,000.0	$ 300,000,000.0
Number of extension option		1 year		1 year
Outstanding under line of credit facility				$ 0
FHLB Facility January 2020
Debt Instrument [Line Items]
Total floating rate debt				0		10,000,000
FHLB Facility June 2020
Debt Instrument [Line Items]
Total floating rate debt				0		15,000,000
FHLB Facility February 2020
Debt Instrument [Line Items]
Total floating rate debt				0		14,500,000
100 Church Street
Debt Instrument [Line Items]
Total fixed rate debt				$ 204,875,000		209,296,000
100 Church Street \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				4.68%
420 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt				$ 294,035,000		299,165,000
420 Lexington Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				3.99%
Landmark Square
Debt Instrument [Line Items]
Total fixed rate debt				$ 100,000,000		100,000,000
Landmark Square \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				4.90%
485 Lexington Avenue
Debt Instrument [Line Items]
Total fixed rate debt				$ 450,000,000		450,000,000
485 Lexington Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				4.25%
1080 Amsterdam Avenue
Debt Instrument [Line Items]
Total fixed rate debt				$ 34,773,000		35,123,000
Total fixed rate debt				33,900,000
Subordinate loan				$ 900,000
1080 Amsterdam Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				3.59%
Term (in Years)				5 years
1080 Amsterdam Avenue \| Mortgage loan \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				350.00%
1080 Amsterdam Avenue \| Senior Subordinated Loans \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)				700.00%
400 East 58th Street
Debt Instrument [Line Items]
Total fixed rate debt				$ 0		39,094,000
762 Madison Avenue
Debt Instrument [Line Items]
Total fixed rate debt				0		771,000
315 West 33rd Street - The Olivia
Debt Instrument [Line Items]
Total fixed rate debt						250,000,000
133 Greene Street
Debt Instrument [Line Items]
Total floating rate debt				$ 15,523,000		15,523,000
133 Greene Street \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				2.00%
106 Spring Street
Debt Instrument [Line Items]
Total floating rate debt				$ 38,025,000		38,025,000
106 Spring Street \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				2.50%
609 Fifth Avenue
Debt Instrument [Line Items]
Total floating rate debt				$ 57,651,000		53,773,000
609 Fifth Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				2.40%
185 Broadway
Debt Instrument [Line Items]
Total floating rate debt				$ 158,478,000		120,110,000
185 Broadway \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				2.85%
712 Madison Avenue
Debt Instrument [Line Items]
Total floating rate debt				$ 28,000,000		28,000,000
712 Madison Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				1.85%
East 220 Street 42
Debt Instrument [Line Items]
Total floating rate debt				$ 510,000,000		0
East 220 Street 42 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				2.75%
719 Seventh Avenue
Debt Instrument [Line Items]
Total floating rate debt				$ 50,000,000		50,000,000
719 Seventh Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)				1.20%
410 Tenth Avenue
Debt Instrument [Line Items]
Total floating rate debt				$ 0		$ 330,819,000
Construction Loans \| 185 Broadway
Debt Instrument [Line Items]
Term (in Years)				3 years
Maximum facility capacity				$ 225,000,000.0
Number of extension options \| extension				2
Period of extension option				1 year
LIBOR Plus 21 Basis Points \| Ticonderoga
Debt Instrument [Line Items]
FHLB advances				$ 60,000,000.0
LIBOR Plus 21 Basis Points \| Ticonderoga \| LIBOR
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				21.00%
115 Spring Street
Debt Instrument [Line Items]
Ownership percentage in disposed asset			49.00%
Deconsolidation of ownership interest percentage			51.00%
Subsequent Event \| FHLB Facility January 2021
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)	39.00%
Period of extension option	1 month