Consolidated Statements of Comprehensive Income Statement (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 30,518us-gaap_NetIncomeLoss	$ 23,979us-gaap_NetIncomeLoss	$ 16,178us-gaap_NetIncomeLoss
Other comprehensive income (loss), net of reclassification adjustments:
Unrealized losses on securities	0	0	(1)
Unrealized gains (losses) on foreign currency forward contracts	0	(65)	65
Foreign currency translation adjustments	(1,532)	105	66
Other comprehensive income (loss), net of tax:	(1,532)	40	130
Comprehensive income	$ 28,986us-gaap_ComprehensiveIncomeNetOfTax	$ 24,019us-gaap_ComprehensiveIncomeNetOfTax	$ 16,308us-gaap_ComprehensiveIncomeNetOfTax

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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