Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Partners Capital [Abstract]
Net income (loss)	$ (128,828)	$ 5,609
Other comprehensive income (loss):
Change in foreign currency translation adjustment	6,963	23,134
Net change in unrealized gains (losses) on available-for-sale marketable debt securities, net of tax	14	(27)
Other comprehensive income (loss), net of tax	6,977	23,107
Comprehensive income (loss)	$ (121,851)	$ 28,716

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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