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Subsequent Events (Details) $ in Millions | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2019 USD ($) | Feb. 07, 2019 USD ($) | Feb. 01, 2019 a | Dec. 31, 2018
Subsequent Event [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 3.80%
Subsequent Event [Member] |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Area of Land | a |  |  | 0.4 |
Gain on sale of non-depreciable real estate assets | $ 9.0 |  |  |
Mortgages |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 4.44%
Mortgages | Subsequent Event [Member] | Post Soho Square [Member] |  |  |  |
Subsequent Event [Line Items] |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate |  | $ 191.3 |  |
Debt Instrument, Interest Rate, Effective Percentage |  | 4.43% |  |

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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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- Definition Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-29(Column G)) -URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014 + Details
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