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Debt and Preferred Equity Investments - Narrative (Details) | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2014 USD ($) | Sep. 30, 2018 USD ($) segment loan | Sep. 30, 2017 segment | Dec. 31, 2017 USD ($)
Preferred equity investment |  |  |  |
Carrying Value |  | $ 1,977,057,000 |  | $ 2,114,041,000
Number of portfolio segments of financial receivables (segment) | segment |  | 1 | 1 |
Additional amount of financing receivables included in other assets |  | $ 84,800,000 |  | 65,500,000
Mezzanine Loan |  |  |  |
Preferred equity investment |  |  |  |
Number Of Debt And Equity Investments Not Performing | loan |  | 1 |  |
Junior Mortgage Participation Acquired in September 2014 |  |  |  |
Preferred equity investment |  |  |  |
Payments to acquire loans | $ 0 |  |  |
Carrying Value |  |  |  | $ 0

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- Definition The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(c)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The cash outflow for the purchase of loan receivable arising from the financing of goods and services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585 + Details
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