Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net Income	$ 15,898	$ 12,415	$ 34,950	$ 27,657
Other Comprehensive Income, net of tax
Net unrealized gains (losses) on available-for-sale securities	804	258	2,512	(162)
Net unrealized gains (losses) on cash flow hedges	142		(196)
Defined benefit plan adjustments	73	36	214	103
Foreign currency translation	1,541	575	5,402	1,202
Other Comprehensive Income, net of tax	2,560	869	7,932	1,143
Comprehensive Income, net of tax	$ 18,458	$ 13,284	$ 42,882	$ 28,800

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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