Business Segments - Reconciliation of Assets from Segment to Consolidated (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Total assets	$ 6,429,832	$ 6,229,278
Corporate Non-Segment [Member]
Segment Reporting Information [Line Items]
Total assets	1,509,241	1,441,616
Same Store [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	4,591,399	4,664,291
Other Real Estate [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total assets	$ 329,192	$ 123,371