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Debt and Preferred Equity Investments - Debt Investments (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |
Mortgage loans on real estate, interest rate | 8.42% |
Debt Investments Held [Abstract] |  |
Carrying value | $ 1,580,306 | $ 2,099,393
Mezzanine Loan with an Initial Maturity Date of March 2020 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 1,300 |
Mezzanine Loan with an Initial Maturity Date of June 2024 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 12,000 |
Mortgage/Mezzanine Loan With An Initial Maturity Due April 2021 |  |
Debt Investments Held [Abstract] |  |
Amount participated out | 96,400 |
Debt investment |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 138,672 |
Senior Financing | 5,288,939 |
Carrying value | 1,341,070 | 1,812,936
Total fixed rate |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 4,115,114 |
Carrying Value | 646,612 | 430,099
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of March 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 1,160,000 |
Carrying Value | 222,775 | 213,185
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of 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 Date of April 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 147,000 |
Carrying Value | 24,952 | 24,932
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 | 38,734 | 36,585
Total fixed rate | Mezzanine Loan With Maturity June 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 326,574 |
Carrying Value | 215,737 | 0
Total fixed rate | Mezzanine Loan, with an Initial Maturity Date of November 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 83,790 |
Carrying Value | 12,714 | 12,706
Total fixed rate | Mezzanine Loan With An Initial Maturity Date Of December 2023 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 180,000 |
Carrying Value | 30,000 | 30,000
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 | 12,950 | 12,941
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 Sold In 2019 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying Value | 0 | 11,000
Total floating rate |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 138,672 |
Senior Financing | 1,173,825 |
Carrying value | 694,458 | 1,382,837
Total floating rate | Mezzanine Loan with an Initial Maturity of January 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 2,509 |
Senior Financing | 29,420 |
Carrying value | 82,696 | 62,493
Total floating rate | Mortgage/Mezzanine Loan Due March 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 69,839 | 0
Total floating rate | Mortgage and Mezzanine Loan with an Initial Maturity Date of April 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 40,000 |
Carrying value | 20,000 | 19,986
Total floating rate | Mezzanine Loan with an Initial Maturity of July 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 4,831 |
Senior Financing | 47,302 |
Carrying value | 15,743 | 12,627
Total floating rate | Mortgage/Mezzanine Loan Due August 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 19,971 | 19,999
Total floating rate | Mezzanine Loan Due September 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 44,737 |
Senior Financing | 0 |
Carrying value | 106,473 | 88,501
Total floating rate | Mortgage And Mezzanine Loan With An Initial Maturity Date Of October 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 63,990 |
Carrying value | 55,573 | 83,449
Total floating rate | Mezzanine Loan Due December 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 19,212 |
Senior Financing | 421,938 |
Carrying value | 51,387 | 88,817
Total floating rate | Mortgage/Mezzanine Loan with an Initial Maturity of December 2020 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 35,386 | 35,266
Total floating rate | Mortgage/Mezzanine Loan With An Initial Maturity Due April 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 10,384 |
Senior Financing | 0 |
Carrying value | 96,570 | 277,694
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 | 49,809 | 24,961
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 | 15,698 | 15,665
Total floating rate | Mezzanine Loan With An Initial Maturity Due July 2021 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 12,999 |
Senior Financing | 151,175 |
Carrying value | 41,395 | 0
Total floating rate | Mezzanine Loan Due December 2022 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 44,000 |
Senior Financing | 0 |
Carrying value | 13,918 | 0
Total floating rate | Mezzanine Loan Due December 2029 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 85,000 |
Carrying value | 20,000 | 0
Total floating rate | Mezzanine Loan Repaid In 2019 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 53,402
Total floating rate | Mezzanine Loan Repaid In 2019, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 79,164
Total floating rate | Mezzanine Loan Repaid In 2019, 3 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 15,333
Total floating rate | Mezzanine Loan Repaid In 2019, 4 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 14,822
Total floating rate | Mortgage And Mezzanine Loan Repaid In 2019 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 154,070
Total floating rate | Mezzanine Loan Repaid In 2019, 5 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 34,886
Total floating rate | Mortgage/Jr.Mortgage Participation Loan Repaid In 2019 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 84,012
Total floating rate | Mortgage And Mezzanine Loan Repaid In 2019, 2 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 37,094
Total floating rate | Mortgage And Mezzanine Loan Repaid In 2019, 3 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 98,804
Total floating rate | Mezzanine Loan Repaid In 2019, 6 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 7,305
Total floating rate | Mezzanine Loan Repaid In 2019, 7 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 14,998
Total floating rate | Mezzanine Loan Repaid In 2019, 8 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | 0 | 21,990
Total floating rate | Mezzanine Loan Repaid In 2019, 9 |  |
Debt Investments Held [Abstract] |  |
Future Funding Obligations | 0 |
Senior Financing | 0 |
Carrying value | $ 0 | $ 37,499

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