Intangible Assets and Intangible Liabilities - Summary of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Intangible assets:
Gross amount	$ 377,109		$ 377,109		$ 436,851
Accumulated amortization	(249,580)		(249,580)		(283,332)
Intangible assets, Net	127,529		127,529		153,519
Intangible liabilities:
Gross amount	156,104		156,104		163,977
Accumulated amortization	(108,249)		(108,249)		(107,981)
Intangible Liabilities, Net	47,855		47,855		$ 55,996
Leases, Acquired-in-Place, Market Adjustment [Member]
Intangible liabilities:
Amortization of above and below-market leases, net (component of "rental revenue")	722	$ 1,910	2,335	$ 4,688
Leases, Acquired-in-Place [Member]
Intangible liabilities:
Amortization of acquired in-place leases (component of "depreciation and amortization")	$ 6,413	$ 9,195	$ 20,183	$ 27,877