Stockholders' Equity - Component of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	$ (47,580)	$ (47,460)
Other comprehensive income (loss)	730	5,945
Total before tax	(46,850)	(41,515)
Tax effect	(268)	(2,202)
Ending balance	(47,118)	(43,717)
Reclassifications out of accumulated other comprehensive loss	0	0
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(47,434)	(47,077)
Other comprehensive income (loss)	735	5,580
Total before tax	(46,699)	(41,497)
Tax effect	(268)	(2,067)
Ending balance	(46,967)	(43,564)
Unrealized Losses
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance	(146)	(383)
Other comprehensive income (loss)	(5)	365
Total before tax	(151)	(18)
Tax effect	0	(135)
Ending balance	$ (151)	$ (153)