Shareholders' Equity and Earnings Per Common Share Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income (loss)									$ 74,144	$ 46,613	$ (79,084)
Net (income) loss attributable to redeemable noncontrolling interests									(8,573)	(6,710)	7,328
Net loss attributable to noncontrolling interests									0	21	3
Net income (loss) attributable to common shareholders									(65,571)	(39,924)	71,753
Distributions to participating securities									(2,489)	(2,599)	(1,655)
Net income (loss) available to common shareholders — basic and diluted	$ 34,390	$ 9,360	$ (3,040)	$ 24,861	$ 710	$ 22,830	$ 20,574	$ (4,190)	$ 63,082	$ 37,325	$ (73,408)
Weighted average number of common shares outstanding — basic and diluted									130,687	119,176	105,359
Earnings (loss) per common share:
Earnings Per Share, Basic	$ 0.25	$ 0.06	$ (0.03)	$ 0.20	$ (0.01)	$ 0.19	$ 0.17	$ (0.04)	$ 0.48	$ 0.31	$ (0.70)
Earnings Per Share, Diluted	$ 0.25	$ 0.06	$ (0.03)	$ 0.20	$ (0.01)	$ 0.19	$ 0.17	$ (0.04)	$ 0.48	$ 0.31	$ (0.70)