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Mortgages Payable - Summary of Outstanding Mortgages Payable (Detail) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Notes payable | $ 967,112 | $ 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 $10,498 and $9,212, respectively | (7,724) | (9,010)
Notes payable | 967,112 | 965,826
Deferred debt issuance costs, accumulated amortization | $ 10,498 | 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) | 3.88% |
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) | 3.38% |
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) | 3.85% |
Mortgage payable gross | $ 56,836 | $ 56,836

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