Notes Receivable, Net - Additional Information (Details) - USD ($)			12 Months Ended
		Feb. 01, 2020	Dec. 31, 2021		Dec. 31, 2020	Oct. 20, 2022	Nov. 02, 2020	Nov. 01, 2020	Apr. 01, 2020	Jan. 14, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Notes receivable			$ 159,638,000		$ 102,100,000
Note receivable accrued interest			21,148,000		13,917,000
Credit loss reserve			5,752,000		1,218,000
Notes receivable, net			$ 153,886,000		100,882,000						$ 114,943,000	$ 111,775,000
Interest Rate			9.00%
Credit loss reserves			$ 153,886,000		100,882,000
OP Units In Settlement Of Note Receivable			21,109
Settlement Amount Of Note Receivable In OP Units			$ 500,000
Mortgage Loans On Real Estate			153,886,000		100,882,000						$ 114,943,000	$ 111,775,000
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)			(114,000)		46,440,000
Allowance for doubtful accounts receivable			$ 38,500,000		$ 45,000,000.0
Maximum [Member]
Accounts Notes And Loans Receivable [Line Items]
Maturity Date			2027-12
Interest Rate	[1]		12.00%
Minimum [Member]
Accounts Notes And Loans Receivable [Line Items]
Maturity Date			2020-04
Interest Rate			5.00%	[1]	5.00%
LUF Portfolio
Accounts Notes And Loans Receivable [Line Items]
Note receivable accrued interest		$ 5,000,000.0
Interest Rate		8.00%
Percentage of mortgage loan collateralized		50.00%
Core Note
Accounts Notes And Loans Receivable [Line Items]
Notes receivable			$ 13,500,000
Notes receivable maturity date			Jun. 01, 2022		Oct. 28, 2021
Notes receivable modified, subsequent payment default			$ 21,600,000		$ 21,600,000
850 Third Avenue Brooklyn, NY
Accounts Notes And Loans Receivable [Line Items]
Notes receivable										$ 54,000,000.0
Interest Rate										9.00%
Fund II
Accounts Notes And Loans Receivable [Line Items]
Note receivable accrued interest								$ 600,000
Notes receivable, net			33,800,000		33,800,000		$ 33,800,000
Mortgage Loans On Real Estate			$ 33,800,000		33,800,000		$ 33,800,000
Fund III
Accounts Notes And Loans Receivable [Line Items]
Maturity Date			2020-07
Equity method investment, ownership percentage by third party			100.00%
Additional credit loss reserve			$ 800,000
Notes receivable modified, subsequent payment default			10,000,000.0
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)			4,500,000
Allowance for doubtful accounts receivable			4,600,000
ASU 2016-13
Accounts Notes And Loans Receivable [Line Items]
Credit loss reserve			400,000
Core Portfolio
Accounts Notes And Loans Receivable [Line Items]
Notes receivable	[1]		154,332,000		96,794,000
Credit loss reserves			153,886,000
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)			4,600,000		$ 600,000
Core Portfolio | Share-based Payment Arrangement, Tranche Three [Member]
Accounts Notes And Loans Receivable [Line Items]
Notes receivable, net			42,000,000.0
Mortgage Loans On Real Estate			42,000,000.0
Core Portfolio | Silver Spring, Maryland [Member]
Accounts Notes And Loans Receivable [Line Items]
Notes receivable, net						$ 16,000,000.0
Mortgage Loans On Real Estate						$ 16,000,000.0
Core Portfolio | Soho, New York [Member]
Accounts Notes And Loans Receivable [Line Items]
Notes receivable, net			43,000,000.0
Mortgage Loans On Real Estate			43,000,000.0
Structured Financing
Accounts Notes And Loans Receivable [Line Items]
Note receivable accrued interest			8,800,000
Loans amortized cost			0
Credit loss reserves			37,900,000
Structured Financing | Non-Collateral Dependent Loans
Accounts Notes And Loans Receivable [Line Items]
Credit loss reserve			1,200
Note receivable accrued interest			12,300,000
Loans amortized cost			$ 142,800,000
Brandywine Portfolio | Core Portfolio
Accounts Notes And Loans Receivable [Line Items]
Notes receivable									$ 38,700,000
Note receivable accrued interest									$ 2,000,000.0
Equity method investment, ownership percentage by third party									24.78%

[1] Includes one and two notes receivable from OP Unit holders, for $6.0 million and $6.5 million at December 31, 2021 and 2020, respectively.