Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net income (loss)	$ 21,765	$ 49,990	$ 108,939	$ 147,421
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(3,222)	(13,034)	(2,235)	(8,377)
Total other comprehensive income (loss), net of tax	(3,222)	(13,034)	(2,235)	(8,377)
Comprehensive income (loss)	18,543	36,956	106,704	139,044
Comprehensive income (loss) from continuing operations attributable to noncontrolling interest in subsidiaries, net of tax	7,769	9,944	33,150	39,250
Comprehensive income (loss) from discontinued operations attributable to noncontrolling interest in subsidiaries, net of tax		2,429		12,412
Less: Total comprehensive income (loss) attributable to noncontrolling interest in subsidiaries, net of tax	7,769	12,373	33,150	51,662
Comprehensive income (loss) attributable to common stockholders	$ 10,774	$ 24,583	$ 73,554	$ 87,382