Notes Receivable, Net - Additional Information (Details) - USD ($)		3 Months Ended		12 Months Ended
		Mar. 31, 2022		Dec. 31, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]
Increase in allowance for credit loss		$ (2,484,000)
Notes receivable		154,331,000		$ 159,638,000
OP Units in settlement of note receivable				21,109
Settlement amount of note receivable in OP units				$ 500,000
Note receivable accrued interest		18,559,000		21,148,000
Notes Receivable		153,161,000		153,886,000
Credit loss reserve		1,170,000		5,752,000
Notes receivable, net		153,161,000		$ 153,886,000
Interest Rate				9.00%
Aggregate loans				$ 153,886,000
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
Fund III
Accounts Notes And Loans Receivable [Line Items]
Increase in allowance for credit loss				$ 4,500,000
venture partner's interest obtained		5,300,000
Note receivable accrued interest		$ 4,700,000
Equity method investment, ownership percentage		100.00%
Maturity Date				2020-07
Credit loss reserve		$ 4,600,000
Maximum
Accounts Notes And Loans Receivable [Line Items]
Maturity Date	[1]	2027-12
Interest Rate		12.00%	[1]	12.00%
Minimum
Accounts Notes And Loans Receivable [Line Items]
Maturity Date	[1]	2020-04
Interest Rate		4.65%	[1]	5.00%
Core Portfolio
Accounts Notes And Loans Receivable [Line Items]
Notes receivable	[1]	$ 154,331,000		$ 154,332,000
Aggregate loans		153,161,000
Core Portfolio | Silver Spring, Maryland
Accounts Notes And Loans Receivable [Line Items]
Notes Receivable				16,000,000.0
Notes receivable, net				16,000,000.0
Core Portfolio | Soho, New York
Accounts Notes And Loans Receivable [Line Items]
Notes Receivable				43,000,000.0
Notes receivable, net				43,000,000.0
Core Portfolio | Three Tranches
Accounts Notes And Loans Receivable [Line Items]
Notes Receivable				42,000,000.0
Notes receivable, net				$ 42,000,000.0
Structured Financing
Accounts Notes And Loans Receivable [Line Items]
Note receivable accrued interest		4,100,000
Loans amortized cost		0
Aggregate loans		27,900,000
Structured Financing | Non-Collateral Dependent Loans
Accounts Notes And Loans Receivable [Line Items]
Note receivable accrued interest		14,300,000
Credit loss reserve		1,200,000
Loans amortized cost		$ 144,800,000

[1] Includes one note receivable from an OP Unit holder, with a balance of $6.0 million at March 31, 2022 and December 31, 2021