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.

+ References

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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

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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-SubTopic 10
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- Definition

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

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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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- 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.

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Mortgages and Other Loans Payable (Details)	1 Months Ended					12 Months Ended
Mortgages and Other Loans Payable (Details)	Feb. 24, 2020 USD ($)	Jan. 31, 2020 USD ($)	Aug. 31, 2019 extension	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2019 USD ($) extension	Dec. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)
Debt Instrument [Line Items]
Total fixed rate debt						$ 1,383,449,000	$ 1,389,717,000
Total floating rate debt						828,434,000	598,442,000
Total mortgages and other loans payable						2,211,883,000	1,988,159,000
Deferred financing costs, net of amortization						(28,630,000)	(26,919,000)
Total mortgages and other loans payable						2,183,253,000	1,961,240,000
Book value of collateral						3,300,000,000	2,600,000,000
Outstanding under line of credit facility						234,013,000	492,196,000
FHLB Facility January 2020
Debt Instrument [Line Items]
Total floating rate debt						$ 10,000,000	0
FHLB Facility January 2020 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)						0.26%
FHLB Facility February 2020
Debt Instrument [Line Items]
Total floating rate debt						$ 15,000,000	0
FHLB Facility February 2020 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)						0.32%
FHLB Facility June 2020
Debt Instrument [Line Items]
Total floating rate debt						$ 14,500,000	0
FHLB Facility June 2020 \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)						0.17%
2017 Master Repurchase Agreement
Debt Instrument [Line Items]
Total floating rate debt						$ 152,684,000	300,000,000
Maximum facility capacity						300,000,000.0		$ 400,000,000.0
Number of extension options \| extension			2
Number of extension option			1 year	1 year	1 year
Outstanding under line of credit facility						$ 152,400,000
2017 Master Repurchase Agreement \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)						2.19%
FHLB Facility, August 2019
Debt Instrument [Line Items]
Total floating rate debt							13,000,000
FHLB Facility, December 2019
Debt Instrument [Line Items]
Total floating rate debt							14,500,000
762 Madison Avenue
Debt Instrument [Line Items]
Total fixed rate debt						$ 771,000	771,000
762 Madison Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						5.00%
100 Church Street
Debt Instrument [Line Items]
Total fixed rate debt						$ 209,296,000	213,208,000
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						$ 299,165,000	300,000,000
420 Lexington Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						3.99%
400 East 58th Street
Debt Instrument [Line Items]
Total fixed rate debt						$ 39,094,000	39,931,000
400 East 58th Street \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						3.00%
Term (in Years)						5 years
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						$ 35,123,000	35,807,000
1080 Amsterdam Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						3.59%
315 West 33rd Street
Debt Instrument [Line Items]
Total fixed rate debt						$ 250,000,000	250,000,000
315 West 33rd Street \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						4.17%
A133 Greene Street
Debt Instrument [Line Items]
Total floating rate debt						$ 15,523,000	15,523,000
A133 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	0
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						$ 53,773,000	0
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						$ 120,110,000	111,869,000
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%
410 Tenth Avenue
Debt Instrument [Line Items]
Total floating rate debt						$ 330,819,000	0
410 Tenth Avenue \| Weighted Average
Debt Instrument [Line Items]
Interest rate, floating rate debt (as a percent)						2.23%
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%
1080 Amsterdam
Debt Instrument [Line Items]
Total fixed rate debt						$ 34,200,000
Subordinate loan						$ 900,000
1080 Amsterdam \| Weighted Average
Debt Instrument [Line Items]
Term (in Years)						5 years
1080 Amsterdam \| Mortgage loan \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						3.50%
1080 Amsterdam \| Senior Subordinated Loans \| Weighted Average
Debt Instrument [Line Items]
Interest rate, fixed rate debt (as a percent)						7.00%
115 Spring Street
Debt Instrument [Line Items]
Total floating rate debt							$ 65,550,000
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
Construction Loans \| 410 Tenth Avenue
Debt Instrument [Line Items]
Maximum facility capacity						$ 465.0
Number of extension options \| extension						2
Construction Loans \| 460 West 34th Street
Debt Instrument [Line Items]
Term (in Years)						3 years
Period of extension option						1 year
LIBOR Plus 25 Basis Points \| Ticonderoga
Debt Instrument [Line Items]
FHLB advances						$ 39,500,000
LIBOR Plus 25 Basis Points \| Ticonderoga \| LIBOR
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)						0.25%
115 Spring Street
Debt Instrument [Line Items]
Ownership percentage in disposed asset			49.00%			49.00%
Deconsolidation of ownership interest percentage			51.00%			51.00%
Subsequent Event \| FHLB Facility January 2020
Debt Instrument [Line Items]
Face amount of loan		$ 10,000,000.0
Interest rate added to base rate (as a percent)		0.165%
Subsequent Event \| FHLB Facility February 2020
Debt Instrument [Line Items]
Face amount of loan	$ 15,000,000.0
Interest rate added to base rate (as a percent)	0.26%