Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement Of Partners Capital [Abstract]
Net income (loss)	$ (9,474)	$ (26,558)
Other comprehensive income (loss):
Change in foreign currency translation adjustment	5,481	(17,329)
Net change on unrealized gains (losses) on available-for-sale investments, net of tax	23	136
Other comprehensive income (loss):	5,504	(17,193)
Comprehensive income (loss):	$ (3,970)	$ (43,751)