Shareholders' Equity, Noncontrolling Interests and Other Comprehensive Loss - Summary of Change in Noncontrolling Interest (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 644,657
Net income (loss)	(66,038)	$ 21,204	$ (15,698)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0	0	0
Other comprehensive income (loss) - unrealized loss on valuation of swap agreements	(74,236)	(35,674)	(2,659)
Acquisition of noncontrolling interest	588
Reclassification of realized interest on swap agreements	15,203	(872)	71
Noncontrolling interest contributions	52,674	161,628	47,560
Noncontrolling interest distributions	(27,574)	(94,289)	(24,793)
Employee Long-term Incentive Plan Unit Awards	10,912	10,957	12,948
Reallocation of noncontrolling interests / Rebalancing adjustment	0	0	0
Ending Balance	607,239	644,657
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	644,657	622,442	648,440
Distributions declared per Common OP Unit	(2,218)	(7,124)	(6,888)
Net income (loss)	(57,279)	(31,841)	(47,137)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	(6,544)	(5,104)	(2,068)
Other comprehensive income (loss) - unrealized loss on valuation of swap agreements	(20,955)	(4,935)	(810)
Acquisition of noncontrolling interest	15,918
Reclassification of realized interest on swap agreements	5,638	80	320
Noncontrolling interest contributions	52,674	161,628	47,560
Noncontrolling interest distributions	(27,574)	(94,289)	(24,793)
Employee Long-term Incentive Plan Unit Awards	10,130	10,411	12,374
Reallocation of noncontrolling interests / Rebalancing adjustment	(7,197)	(6,611)	(4,556)
Ending Balance	607,239	644,657	622,442
Noncontrolling Interests | Cumulative Effect of Change in Accounting Principle
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(11)
Ending Balance		(11)
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	546,987	518,219	545,519
Distributions declared per Common OP Unit	0	0	0
Net income (loss)	(57,404)	(35,677)	(49,709)
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	0	0	0
Other comprehensive income (loss) - unrealized loss on valuation of swap agreements	(18,246)	(3,036)	(681)
Acquisition of noncontrolling interest	15,918
Reclassification of realized interest on swap agreements	5,464	142	323
Noncontrolling interest contributions	52,674	161,628	47,560
Noncontrolling interest distributions	(27,574)	(94,289)	(24,793)
Employee Long-term Incentive Plan Unit Awards	0	0	0
Reallocation of noncontrolling interests / Rebalancing adjustment	0	0	0
Ending Balance	517,808	546,987	518,219
Noncontrolling Interests | Noncontrolling Interests in Partially-Owned Affiliates | Cumulative Effect of Change in Accounting Principle
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(11)
Ending Balance		(11)
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	97,670	104,223	102,921
Distributions declared per Common OP Unit	(2,218)	(7,124)	(6,888)
Net income (loss)	125	3,836	2,572
Conversion of OP Units to Common Shares by limited partners of the Operating Partnership	(6,544)	(5,104)	(2,068)
Other comprehensive income (loss) - unrealized loss on valuation of swap agreements	(2,709)	(1,899)	(129)
Acquisition of noncontrolling interest	0
Reclassification of realized interest on swap agreements	174	(62)	(3)
Noncontrolling interest contributions	0	0	0
Noncontrolling interest distributions	0	0	0
Employee Long-term Incentive Plan Unit Awards	10,130	10,411	12,374
Reallocation of noncontrolling interests / Rebalancing adjustment	(7,197)	(6,611)	(4,556)
Ending Balance	89,431	97,670	$ 104,223
Noncontrolling Interests | Operating Partnership, as General Partner or Managing Member | Cumulative Effect of Change in Accounting Principle
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 0
Ending Balance		$ 0