Statements of Comprehensive Income (Loss) Statement - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net Income (Loss) Attributable to Parent	$ 9,193	$ 7,601	$ 16,344	$ 21,540
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss), Net of Tax	1	29	45	23
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	133	596	1,253	1,234
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 9,327	$ 8,226	$ 17,642	$ 22,797