Debt and Preferred Equity Investments - Debt Investment (Details) - USD ($)	1 Months Ended	3 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Aggregate weighted average current yield (as a percent)		5.90%
Debt Investments Held [Abstract]
Carrying Value		$ 1,097,202,000	$ 1,076,542,000
Carrying Value		1,097,202,000	1,076,542,000
Junior Mortgage Due July 2021
Debt Investments Held [Abstract]
Amount participated out		66,600,000
Mezzanine Loan With Maturity June 2023
Debt Investments Held [Abstract]
Loan interest income		0
Mezzanine Loan with an Initial Maturity Date of June 2024
Debt Investments Held [Abstract]
Amount participated out		12,000,000.0
Loan interest income		0
Mezzanine Loan Due March 2022
Debt Investments Held [Abstract]
Amount participated out		400,000
Debt Investments in Mortgage Loans
Debt Investments Held [Abstract]
Future Funding Obligations		106,935,000
Senior Financing		4,543,210,000
Allowance for loan loss		(13,213,000)	(13,213,000)
Carrying Value		834,221,000	816,756,000
Total fixed rate
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		2,782,737,000
Carrying Value		488,201,000	477,509,000
Total fixed rate | Junior Mortgage Due July 2021
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		67,000,000
Carrying Value		42,820,000	32,888,000
Total fixed rate | Mezzanine Loan, September 2021
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		15,000,000
Carrying Value		3,500,000	3,500,000
Total fixed rate | Mortgage/Mezzanine Loan Due October 2021
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		63,750,000
Carrying Value		56,246,000	56,244,000
Total fixed rate | Mezzanine Loan With An Initial Maturity Of August 2022
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		280,000,000
Carrying Value		41,652,000	41,057,000
Total fixed rate | Mezzanine Loan With Maturity June 2023
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		359,237,000
Carrying Value		225,367,000	225,204,000
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of June 2024
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		105,000,000
Carrying Value		13,366,000	13,366,000
Total fixed rate | Mezzanine Loan, with an Initial Maturity Date of January 2025
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		95,000,000
Carrying Value		30,000,000	30,000,000
Total fixed rate | Mezzanine Loan with an Initial Maturity Date of June 2027
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		1,712,750,000
Carrying Value		55,250,000	55,250,000
Total fixed rate | Mezzanine Loan With Initial Maturity Date Of December 2029
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		85,000,000
Carrying Value		20,000,000	20,000,000
Total floating rate
Debt Investments Held [Abstract]
Future Funding Obligations		106,935,000
Senior Financing		1,760,473,000
Carrying Value		359,233,000	352,460,000
Total floating rate | Mezzanine Loan Due April 2021
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		275,000,000
Carrying Value		49,992,000	49,956,000
Total floating rate | Junior Mortgage Participation/Mezzanine Loan Due July 2021
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		60,000,000
Carrying Value		15,742,000	15,733,000
Total floating rate | Mezzanine Loan Due July 2021
Debt Investments Held [Abstract]
Future Funding Obligations		5,761,000
Senior Financing		177,415,000
Carrying Value		36,639,000	35,318,000
Total floating rate | Mezzanine Loan Due July 2021, 2
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		61,744,000
Carrying Value		29,130,000	29,106,000
Total floating rate | Mezzanine Loan Due March 2022
Debt Investments Held [Abstract]
Future Funding Obligations		0
Senior Financing		1,115,000,000
Carrying Value		129,330,000	127,915,000
Total floating rate | Mezzanine Loan Due April 2022 | Subsequent Event
Debt Investments Held [Abstract]
Extension term	1 year
Total floating rate | Mortgage/Mezzanine Loan Due May 2022
Debt Investments Held [Abstract]
Future Funding Obligations		6,769,000
Senior Financing		0
Carrying Value		60,922,000	60,532,000
Total floating rate | Mezzanine Loan Due December 2022
Debt Investments Held [Abstract]
Future Funding Obligations		42,117,000
Senior Financing		0
Carrying Value		15,918,000	14,011,000
Total floating rate | Mezzanine Loan Due May 2023
Debt Investments Held [Abstract]
Future Funding Obligations		52,288,000
Senior Financing		71,314,000
Carrying Value		$ 21,560,000	$ 19,889,000