Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Consolidated net income (loss)	$ 28,953	$ 18,656	$ 51,045	$ 33,206
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	4,571	(149)	11,052	4,117
Available for sale securities	978	(1,923)	691	32
Total other comprehensive income (loss), net of tax	5,549	(2,072)	11,743	4,149
Comprehensive income (loss)	34,502	16,584	62,788	37,355
Less: Comprehensive income (loss) attributable to noncontrolling interest in subsidiaries, net of tax	7,961	3,787	12,607	6,070
Comprehensive income (loss) attributable to common stockholders	$ 26,541	$ 12,797	$ 50,181	$ 31,285