Prepaid Expenses and Other Current Assets and Other Assets (Schedule of Other Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Prepaid Expenses and Other Current Assets and Other Assets [Abstract]
Straight-line rent receivable	$ 340,078	$ 321,816
Interest rate swap asset	36,710	12,123
Loan receivables	5,387	5,931
Deferred lease costs, net	5,294	4,788
Deferred tax asset - long term	51,331	53,722
Long-term investments	48,719	57,575
Other	26,506	22,037
Total other assets	$ 514,025	$ 477,992