Tenant Leases (Schedule of Future Minimum Lease Payments to be Received) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
2018	$ 2,065,850
2019	1,671,115
2020	1,361,404
2021	1,147,928
2022	881,117
Thereafter	2,958,666
Total	$ 10,086,080