Balance Sheet Components - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 845,254	$ 679,617
Other comprehensive income (loss) before reclassifications	(4,694)	769
Amounts reclassified from other comprehensive income (loss), net of tax	0	(417)
Net current-period other comprehensive income (loss), net of tax	(4,694)	352
Ending balance	878,500	730,485
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(9,446)	(10,854)
Ending balance	(14,140)	(10,502)
Foreign currency translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(9,446)	(11,274)
Other comprehensive income (loss) before reclassifications	(4,694)	669
Amounts reclassified from other comprehensive income (loss), net of tax	0	0
Net current-period other comprehensive income (loss), net of tax	(4,694)	669
Ending balance	(14,140)	(10,605)
Unrealized gain (loss) on interest rate swap hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	420
Other comprehensive income (loss) before reclassifications	0	100
Amounts reclassified from other comprehensive income (loss), net of tax	0	(417)
Net current-period other comprehensive income (loss), net of tax	0	(317)
Ending balance	$ 0	$ 103

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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