Shareholders' Equity and Earnings (Loss) Per Common Share - Basic and Diluted Earnings (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Shareholders' Equity and Earnings Per Common Share
Net income (loss)	$ (3,318)	$ (40,263)	$ (27,387)	$ 7,912
Net (income) loss attributable to redeemable noncontrolling interests	345	3,483	2,575	(1,767)
Net loss attributable to noncontrolling interests			1,108
Net income (loss) attributable to common shareholders	(2,973)	(36,780)	(23,704)	6,145
Distributions to participating securities	(734)	(907)	(734)	(907)
Net income (loss) available to common shareholders - basic	(3,567)	(37,687)	(24,298)	5,238
Net income (loss) available to common shareholders - diluted	$ (3,707)	$ (37,687)	$ (24,438)	$ 5,238
Weighted average number of common shares outstanding - basic	131,480	133,613	131,510	134,078
Weighted average number of common shares outstanding - diluted	131,480	133,613	131,510	134,078
Earnings (loss) per common share - basic	$ (0.03)	$ (0.28)	$ (0.19)	$ 0.04
Earnings (loss) per common share - diluted	$ (0.03)	$ (0.28)	$ (0.19)	$ 0.04