Intangible Assets and Intangible Liabilities - Summary of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Intangible assets:
Gross amount	$ 436,851		$ 436,851		$ 466,099
Accumulated amortization	(269,176)		(269,176)		(262,930)
Intangible assets, Net	167,675		167,675		203,169
Intangible liabilities:
Gross amount	163,977		163,977		174,670
Accumulated amortization	(102,492)		(102,492)		(100,881)
Intangible Liabilities, Net	61,485		61,485		$ 73,789
Leases, Acquired-in-Place, Market Adjustment [Member]
Intangible liabilities:
Amortization of above and below-market leases, net (component of "rental revenue")	1,910	$ 2,571	4,688	$ 8,614
Leases, Acquired-in-Place [Member]
Intangible liabilities:
Amortization of acquired in-place leases (component of "depreciation and amortization")	$ 9,195	$ 11,379	$ 27,877	$ 35,909