Debt - Schedule of Mortgages Payable (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
Jun. 30, 2017	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Payable to former parent		$ 0	$ 283,232
Mortgages
Debt Instrument [Line Items]
Variable interest rate		2.95%
Fixed interest rate		4.79%
Interest rate on payable to Vornado		0.00%
Variable rate amount		$ 1,152,106	547,291
Fixed rate amount		836,141	620,327
Mortgages payable		1,988,247	1,167,618
Unamortized deferred financing costs and premium/discount, net		(10,573)	(2,604)
Mortgages payable, net		1,977,674	1,165,014
Payable to former parent		0	$ 283,232
Revolving credit facility
Debt Instrument [Line Items]
Proceeds from Vornado's revolving credit facility	$ 115,600	$ 5,200

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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Amount of unamortized debt discount (premium) and debt issuance costs.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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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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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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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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