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Mortgages Payable - Summary of Outstanding Mortgages Payable (Detail) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2019 | Dec. 31, 2018
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Notes payable | $ 969,673 | $ 965,826
Mortgages |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Mortgage payable gross | 974,836 | 974,836
Deferred debt issuance costs, net of accumulated amortization of $13,074 and $9,212, respectively | (5,163) | (9,010)
Notes payable | 969,673 | 965,826
Deferred debt issuance costs, accumulated amortization | $ 13,074 | 9,212
Mortgages | Paramus |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Oct. 01, 2021 |
Interest rate (in percentage) | 4.72% |
Mortgage payable gross | $ 68,000 | 68,000
Mortgages | 731 Lexington Avenue | Retail Space |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Aug. 01, 2022 |
Interest rate (in percentage) | 3.47% |
Mortgage payable gross | $ 350,000 | 350,000
Mortgages | 731 Lexington Avenue | Office Space |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Jun. 01, 2024 |
Interest rate (in percentage) | 2.93% |
Mortgage payable gross | $ 500,000 | 500,000
Mortgages | Rego Park II | Retail Space |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Dec. 01, 2025 |
Interest rate (in percentage) | 3.39% |
Mortgage payable gross | $ 56,836 | $ 56,836

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