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Debt and Preferred Equity Investments - Debt and Preferred Equity Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Debt Instrument [Line Items] |  |
Carrying Value | $ 1,052,110 | $ 1,076,542
Senior Financing | 6,599,960 |
Total floating rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | 281,494 |
Face Value | 283,019 |
Total fixed rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | 770,616 |
Face Value | 782,216 |
Senior Mortgage Debt |  |
Debt Instrument [Line Items] |  |
Carrying Value | 19,245 |
Senior Financing | $ 0 |
Weighted Average Yield at End of Period | 6.57% |
Senior Mortgage Debt | Total floating rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | $ 17,995 |
Face Value | 18,241 |
Senior Mortgage Debt | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | 1,250 |
Face Value | 1,250 |
Mezzanine Debt |  |
Debt Instrument [Line Items] |  |
Carrying Value | 763,256 |
Senior Financing | $ 4,637,210 |
Weighted Average Yield at End of Period | 6.53% |
Mezzanine Debt | Total floating rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | $ 263,499 |
Face Value | 264,778 |
Mezzanine Debt | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | 499,757 |
Face Value | 510,116 |
Preferred Equity |  |
Debt Instrument [Line Items] |  |
Carrying Value | 269,609 |
Senior Financing | $ 1,962,750 |
Weighted Average Yield at End of Period | 9.90% |
Preferred Equity | Total floating rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | $ 0 |
Face Value | 0 |
Preferred Equity | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Carrying Value | 269,609 |
Face Value | $ 270,850 |
Minimum | Senior Mortgage Debt | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Interest rate | 3.50% |
Minimum | Mezzanine Debt | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Interest rate | 2.90% |
Minimum | Preferred Equity | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Interest rate | 6.50% |
Maximum | Mezzanine Debt | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Interest rate | 14.30% |
Maximum | Preferred Equity | Total fixed rate |  |
Debt Instrument [Line Items] |  |
Interest rate | 11.00% |
LIBOR | Minimum | Senior Mortgage Debt | Total floating rate |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 3.50% |
LIBOR | Minimum | Mezzanine Debt | Total floating rate |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 4.95% |
LIBOR | Maximum | Mezzanine Debt | Total floating rate |  |
Debt Instrument [Line Items] |  |
Basis spread on variable rate | 12.97% |

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- Definition Mortgage Loans on Real Estate, Senior Financing + References No definition available. + Details
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Balance Type: | debit
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
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- Definition Rate of interest on investment. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
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- Definition Nominal or face amount on the investment owned. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 20 -Section 10 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6438156&loc=d3e57880-113973 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 10 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6431724&loc=d3e32938-113948 + Details
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- Definition The percentage points (also referred to as 'margin') added to the reference rate as stated in the loan agreement and used to compute the variable rate on the loans receivable. For instance, the loan agreement might state that the interest rate the borrower is obligated to pay is the London Interbank Offered Rate (LIBOR) plus three quarters (3/4) of a percentage point adjusted quarterly (each three months). LIBOR in this example is the index or reference rate, 3/4 percentage point is the margin, the reference rate plus the margin is the fully indexed rate. This element would be used to report separately the margin. + References No definition available. + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -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=120400017&loc=d3e572229-122910 + Details
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