Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Consolidated Statements Of Comprehensive Income [Abstract]
Net income (loss)	$ 9,447	$ 10,943	$ 23,220	$ (12,698)
Other comprehensive income (loss):
Foreign currency translation adjustments	585	(2,652)	(248)	(1,320)
Unrealized gain on investments, net of tax	0	41	0	41
Unrealized gain (loss) on derivative, net of tax	(2,261)	244	(3,546)	1,077
Other	(191)	0	(206)	0
Other comprehensive loss	(1,867)	(2,367)	(4,000)	(202)
Comprehensive income (loss)	$ 7,580	$ 8,576	$ 19,220	$ (12,900)

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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