Leases - Additional Information (Details) $ in Thousands		12 Months Ended
	Sep. 24, 2021 USD ($)	Dec. 31, 2021 USD ($) Agreement	Dec. 31, 2020 USD ($) Item Agreement	Dec. 31, 2019 USD ($)
Operating Leased Assets [Line Items]
Variable lease revenues		$ 58,300	$ 57,100
Payments to Tenant	$ 5,400
Part payment received from tenant	$ 300
Lease agreement purchase price			14,500
Operating lease right-of-use asset		40,743	76,268	$ 60,000
Lease liability - operating lease		38,759	88,816	58,000
Gain (loss) on termination of lease		3,615	0	0
Gain on disposition of properties		10,521	683	30,324
Net income		26,030	(65,718)	23,234
Impairment charges		9,925	85,598	$ 1,721
COVID-19
Operating Leased Assets [Line Items]
Net income		16,300	134,000
Pro rata earnings		8,600	53,100
Aggregate credit losses and rent abatements		6,400	48,400
Pro rata credit losses and rent abatements		6,300	32,500
Impairment charges		9,900	85,600
Pro rata asset impairment charges		$ 2,300	$ 20,600
Number of rent concession agreements | Agreement		96	288
Number of rent concession agreements for rent deferral | Agreement		18	226
Number of rent concession agreements for rent abatements | Agreement		78	60
Number of rent concession agreements accounted as no change in contract | Agreement		16
Deferred receivables		$ 5,400	$ 10,600
Rent abatements		6,500	1,900
Pro rata rent abatement		$ 4,300	$ 2,600
Pro rata core leased occupancy rate percentage		93.20%	90.90%
Pro rata fund leased occupancy rate percentage		91.40%	88.30%
COVID-19 | Core Portfolio
Operating Leased Assets [Line Items]
Percentage of rent collections		98.00%	91.00%
COVID-19 | Opportunity Funds
Operating Leased Assets [Line Items]
Percentage of rent collections		94.00%	82.00%
Fund IV Property
Operating Leased Assets [Line Items]
Operating lease right-of-use asset		$ 31,400
Termination cost		3,600
Lease liability - operating lease		46,000
Building improvements and other assets		10,300
Gain (loss) on termination of lease		700
Gain on disposition of properties		200
Impairment charge of right-of-use asset			$ 12,300
BSP II
Operating Leased Assets [Line Items]
Number of operating lease | Item			1
Branch Plaza
Operating Leased Assets [Line Items]
Number of operating lease | Item			1
Operating Lease term			22 years
1238 Wisconsin
Operating Leased Assets [Line Items]
Lease agreement purchase price			$ 11,500
Operating lease right-of-use asset			1,900
Operating lease liability			$ 1,900
Accounting Standards Update 2016-02 | 991 Madison Avenue Manhattan, NY
Operating Leased Assets [Line Items]
Capital lease term			49 years
Operating Lease term			15 years
Office Lease
Operating Leased Assets [Line Items]
Number of operating lease | Item			1
Operating lease right-of-use asset			$ 1,700
Lease liability - operating lease			$ 1,700
Rye Corporate Office Lease
Operating Leased Assets [Line Items]
Operating lease right-of-use asset		400
Operating lease liability		$ 400
Minimum
Operating Leased Assets [Line Items]
Operating lease term		1 month
Minimum | Consolidated Total Revenues | Customer Concentration Risk
Operating Leased Assets [Line Items]
Concentration risk, percentage		10.00%	10.00%	10.00%
Maximum
Operating Leased Assets [Line Items]
Operating lease term		60 years