Leases - Rental Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Cash rent	$ 1,102,538	$ 1,121,482	$ 1,110,983
Straight-line rent	28,032	39,772	46,968
Lease intangible amortization	(2,538)	(4,178)	(5,366)
Property operating cost reimbursements	5,559	5,375	3,056
Sub-lease	21,496	16,178	16,383
Total fixed	1,155,087	1,178,629	1,172,024
Variable	81,310	78,179	78,699
Income from direct financing leases	837	1,059	1,562
Total rental revenue	$ 1,237,234	$ 1,257,867	$ 1,252,285