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Debt and Preferred Equity Investments - Additional Information (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Aggregate weighted average current yield (as a percent) | 6.26% |
Debt Investments Held [Abstract] |  |
Carrying Value | $ 1,153,363 | $ 1,580,306
Mezzanine Loan With Initial Maturity Date Of January 2021 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 66,600 |
Mezzanine Loan with an Initial Maturity Date of June 2024 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 12,000 |
Mezzanine Loan Due March 2022 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 400 |
Debt Investments in Mortgage Loans |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 165,023 |
Senior Financing | 4,930,044 |
Allowance for loan loss | (19,010) | 0
Carrying Value | 896,798 | 1,341,070
Total fixed rate |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 10,000 |
Senior Financing | 2,781,827 |
Carrying Value | 476,724 | 499,410
Total fixed rate | Mortgage And Mezzanine Loan With An Initial Maturity Date Of October 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 63,750 |
Carrying Value | 56,242 | 55,573
Total fixed rate | Mezzanine Loan With Initial Maturity Date Of January 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 10,000 |
Senior Financing | 67,000 |
Carrying Value | 32,805 | 0
Total fixed rate | Mezzanine Loan, September 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 15,000 |
Carrying Value | 3,500 | 3,500
Total fixed rate | Mezzanine Loan With An Initial Maturity Of August 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 280,000 |
Carrying Value | 40,458 | 38,734
Total fixed rate | Mezzanine Loan With Maturity June 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 348,327 |
Carrying Value | 225,204 | 215,737
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of June 2024 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 115,000 |
Carrying Value | 13,265 | 12,950
Total fixed rate | Mezzanine Loan, with an Initial Maturity Date of January 2025 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 95,000 |
Carrying Value | 30,000 | 30,000
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of June 2027 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 1,712,750 |
Carrying Value | 55,250 | 55,250
Total fixed rate | Mezzanine Loan With Initial Maturity Date Of December 2029 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 85,000 |
Carrying Value | 20,000 | 20,000
Total fixed rate | Mezzanine Loan Repaid In 2020, 1 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 24,952
Total fixed rate | Mezzanine Loan Repaid In 2020, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 30,000
Total fixed rate | Mezzanine Loan Repaid In 2020, 3 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 12,714
Total floating rate |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 155,023 |
Senior Financing | 2,148,217 |
Carrying Value | 439,084 | 841,660
Total floating rate | Mezzanine Loan Repaid In 2020, 1 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 51,387
Total floating rate | Junior Mortgage Loan With An Initial Maturity April 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 40,000 |
Carrying Value | 20,000 | 20,000
Total floating rate | Mezzanine Loan With An Initial Maturity Due April 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 275,000 |
Carrying Value | 49,919 | 49,809
Total floating rate | Jr Mortgage Participation/Mezzanine Loan with an Initial Maturity of July 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 60,000 |
Carrying Value | 15,724 | 15,698
Total floating rate | Mezzanine Loan With An Initial Maturity Due July 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 7,933 |
Senior Financing | 169,540 |
Carrying Value | 46,613 | 41,395
Total floating rate | Mezzanine Loan Due July 2021, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 5,329 |
Senior Financing | 54,204 |
Carrying Value | 23,753 | 15,743
Total floating rate | Mezzanine Loan Due March 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 1,115,000 |
Carrying Value | 126,486 | 222,775
Total floating rate | Mortgage/Mezzanine Loan Due May 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 7,425 |
Senior Financing | 0 |
Carrying Value | 60,116 | 0
Total floating rate | Mezzanine Loan Due December 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 44,000 |
Senior Financing | 0 |
Carrying Value | 13,987 | 13,918
Total floating rate | Mortgage Loan Due February 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 35,303 |
Senior Financing | 375,241 |
Carrying Value | 63,899 | 0
Total floating rate | Mezzanine Loan Due May 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 55,033 |
Senior Financing | 59,232 |
Carrying Value | 18,587 | 69,839
Total floating rate | Mortgage/Mezzanine Loan Repaid In 2020, 1 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 35,386
Total floating rate | Mortgage Loan Repaid In 2020, 1 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 19,971
Total floating rate | Mortgage Loan Repaid In 2020, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 106,473
Total floating rate | Mortgage/Mezzanine Loan Repaid In 2020, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 96,570
Total floating rate | Mortgage/Mezzanine Loan Repaid In 2020, 3 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | $ 0 | $ 82,696

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