Summary of Significant Accounting Policies - Lease Income for Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Fixed lease income	$ 176,388	$ 165,559	$ 505,400	$ 514,640
Variable lease income	12,953	11,995	34,589	32,829
Straight-line rent write-off	0	0	0	(2,850)
Total lease income	$ 189,341	$ 177,554	$ 539,989	$ 544,619