Revenue Recognition (Rental Income Table) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating Leased Assets [Line Items]
Total cash rental income	$ 277,079		$ 805,872
Straight-line rent adjustments	888		2,544	$ (5,394)
Ground rent in revenue	5,264		12,634
Other rental revenue	22		147
Total rental income	283,253	$ 267,555	821,197	$ 762,711
Operating Leases, Future Minimum Base Ground Payments Receivable	151,511		151,511
Straight Line Rent Adjustments, Net	330,517		330,517
Operating Leases, Future Minimum Payments Receivable	17,349,669		17,349,669
Operating Leases, Future Income to Be Recognized	17,831,697		17,831,697
Operating Leases, Future Minimum Base Ground Payments Receivable, Thereafter	100,259		100,259
Operating Leases, Future Minimum Payments Receivable, Thereafter	13,054,680		13,054,680
Operating Leases, Future Income to Be Recognized, in Five Years	1,026,494		1,026,494
Operating Leases, Future Minimum Base Ground Payments Receivable, In Five Years	12,069		12,069
Straight Line Rent Adjustments, in Five Years	28,900		28,900
Operating Leases, Future Minimum Payments Receivable, in Five Years	985,525		985,525
Operating Leases, Future Income to Be Recognized, Thereafter	13,372,186		13,372,186
Straight Line Rent Adjustments, Thereafter	217,247		217,247
Operating Leases, Future Income to Be Recognized, in Four Years	1,026,253		1,026,253
Operating Leases, Future Minimum Base Ground Payments Receivable, In Four Years	12,063		12,063
Straight Line Rent Adjustments, in Four Years	30,072		30,072
Operating Leases, Future Minimum Payments Receivable, in Four Years	984,118		984,118
Operating Leases, Future Income to Be Recognized, in Three Years	1,059,437		1,059,437
Operating Leases, Future Minimum Base Ground Payments Receivable, In Three Years	12,057		12,057
Straight Line Rent Adjustments, in Three Years	31,035		31,035
Operating Leases, Future Minimum Payments Receivable, in Three Years	1,016,345		1,016,345
Operating Leases, Future Income to Be Recognized, in Two Years	1,076,135		1,076,135
Operating Leases, Future Minimum Base Ground Payments Receivable, In Two Years	12,051		12,051
Straight Line Rent Adjustments, in Two Years	22,375		22,375
Operating Leases, Future Minimum Payments Receivable, in Two Years	1,041,709		1,041,709
Operating Leases, Future Minimum Base Ground Payments Receivable, Current	3,012		3,012
Straight Line Rent Adjustments, Current	888		888
Operating Leases, Future Minimum Payments Receivable, Current	267,292		267,292
Operating Leases, Future Income to Be Recognized, Current	271,192		271,192
Property Subject to Operating Lease
Operating Leased Assets [Line Items]
Total cash rental income	37,875		113,486
Building | Property Subject to Operating Lease
Operating Leased Assets [Line Items]
Total cash rental income	187,310		537,676
Land | Property Subject to Operating Lease
Operating Leased Assets [Line Items]
Total cash rental income	$ 51,894		$ 154,710