Noncontrolling Interest Represented by Preferred Operating Partnership Units - Balances of OP Units (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Noncontrolling Interest [Line Items]
Preferred OP Units	$ 170,248	$ 172,052
Series A Units
Noncontrolling Interest [Line Items]
Preferred OP Units	14,818	13,788
Series B Units
Noncontrolling Interest [Line Items]
Preferred OP Units	38,068	40,902
Series D Units
Noncontrolling Interest [Line Items]
Preferred OP Units	$ 117,362	$ 117,362