Tenant Leases (Future Minimum Rentals To Be Received Under Non-Cancelable Operating Leases) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)
Property Subject to or Available for Operating Lease [Line Items]
2019	$ 314,708
2020	306,559
2021	284,120
2022	258,076
2023	220,533
2024 and thereafter	923,061
Total	$ 2,307,057
Tenant Leases [Member]
Property Subject to or Available for Operating Lease [Line Items]
Operating leases with various expiration dates through year	Dec. 31, 2036
Multi-Family Properties [Member]
Property Subject to or Available for Operating Lease [Line Items]
Lease period	1 year