Leases - Lease Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Interest and Other Income [Abstract]
Fixed income from operating leases	$ 262,558	$ 255,447	$ 770,327	$ 730,277
Variable income from operating leases	63,972	57,153	183,254	177,742
Interest income from direct financing leases	$ 2,150	$ 9,590	$ 7,569	$ 33,304