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Mortgages Payable - Summary of Outstanding Mortgages Payable (Detail) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Notes payable | $ 1,162,928 | $ 1,240,222
Mortgages |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Mortgage payable gross | 1,171,226 | 1,252,440
Deferred debt issuance costs, net of accumulated amortization of $10,219 and $6,315, respectively | (8,298) | (12,218)
Notes payable | $ 1,162,928 | 1,240,222
Mortgages | Paramus |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Oct. 05, 2018 |
Interest rate (in percentage) | 2.90% |
Mortgage payable gross | $ 68,000 | 68,000
Mortgages | Rego Park II | Retail Space |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Maturity date | Nov. 30, 2018 |
Interest rate (in percentage) | 4.11% |
Mortgage payable gross | $ 253,226 | 256,194
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) | 3.51% |
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) | 3.06% |
Mortgage payable gross | $ 500,000 | 500,000
Mortgages | Rego Park I | Retail Space |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Interest rate (in percentage) | 0.00% |
Mortgage payable gross | $ 0 | $ 78,246

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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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