UNAUDITED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 25,880	$ 3,966	$ 4,487	$ (16,905)
Other comprehensive income (loss):
Unrealized gains on available-for-sale securities (net of taxes of $20, $0, $122 and $0, respectively)	27	0	159	0
Reclassification adjustment for losses on available-for-sale securities included in net income (loss) (net of taxes of $29, $0, $79 and $0, respectively)	47	0	143	0
Foreign currency translation adjustments	15,024	(1,178)	20,847	44,659
Other comprehensive income (loss)	15,098	(1,178)	21,149	44,659
Comprehensive income	$ 40,978	$ 2,788	$ 25,636	$ 27,754