Leases - Supplemental balance sheet information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating leases:
Operating lease right-of-use assets	$ 51,342	$ 57,141
Operating lease liabilities	58,005	64,416
Finance leases:
Property and equipment, at cost	4,033,135	3,230,428
Accumulated amortization	(702,944)	(558,560)
Real Estate Assets, net	3,330,191	2,671,868
Finance lease liabilities	41,718	45,141
Finance leased assets
Operating leases:
Operating lease right-of-use assets	51,342	57,141
Operating lease liabilities	58,005	64,416
Finance leases:
Property and equipment, at cost	49,554	50,437
Accumulated amortization	(8,864)	(4,830)
Real Estate Assets, net	$ 40,690	$ 45,607