Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 76,080	$ 39,939	$ 48,763
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustment, net of tax of $6, ($4) and ($348) for the years ended December 31, 2018, 2017 and 2016	(17)	12	569
Unrealized gain (loss) on available-for-sale securities, net of tax of $111, $100, and ($32) for the years ended December 31, 2018, 2017 and 2016, respectively	(292)	(388)	241
Other comprehensive income (loss)	(309)	(376)	810
Comprehensive income (loss)	75,771	39,563	49,573
Comprehensive (income) loss attributable to noncontrolling interests	(551)	(2,927)	(261)
Comprehensive income (loss) attributable to stockholders	$ 75,220	$ 36,636	$ 49,312