CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interests [Member]	Total
Balance at Dec. 31, 2016	$ 49,211	$ 1,075,600	$ 473,625	$ (45,413)		$ 1,553,023
Net income (loss)			148,382		$ 6,162	154,544
Other comprehensive income (loss)				2,695		2,695
Share-based compensation		20,877				20,877
Issuance of common stock, net	570	(12,272)				(11,702)
Contributions from noncontrolling interests					2,842	2,842
Distributions to noncontrolling interests					(17,499)	(17,499)
Balance at Dec. 31, 2017	49,781	1,084,205	622,007	(42,718)	(8,495)	1,704,780
Net income (loss)			83,436		14,345	97,781
Other comprehensive income (loss)				(2,731)	(221)	(2,952)
Share-based compensation		21,544				21,544
Issuance of common stock, net	245	(2,830)				(2,585)
Contributions from noncontrolling interests					3,797	3,797
Distributions to noncontrolling interests					(29,000)	(29,000)
Balance at Dec. 31, 2018	50,026	1,102,919	701,681	(45,449)	(21,288)	1,787,889
Cumulative effect of accounting change			(3,762)		(1,714)	(5,476)
Net income (loss)			(387,690)		27,465	(360,225)
Other comprehensive income (loss)				3,349	393	3,742
Share-based compensation		17,571				17,571
Issuance of common stock, net	253	(2,518)				(2,265)
Contributions from noncontrolling interests					9,813	9,813
Distributions to noncontrolling interests					(46,500)	(46,500)
Recognized fair value of noncontrolling interest in joint venture upon consolidation					20,500	20,500
Balance at Dec. 31, 2019	$ 50,279	$ 1,117,972	$ 313,991	$ (42,100)	$ (9,617)	$ 1,430,525