Leases - Lease Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Interest and Other Income [Abstract]
Fixed income from operating leases	$ 253,859	$ 237,223
Variable income from operating leases	60,829	56,999
Interest income from direct financing leases	$ 3,269	$ 13,524