Stockholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	$ 335,338
Ending Balance	350,780
Unrealized Gains on Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	346
Other comprehensive income before reclassifications	36
Amounts reclassified from AOCI, net of tax	(16)
Net other comprehensive income	20
Ending Balance	366
Cumulative Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(23,257)
Other comprehensive income before reclassifications	4,572
Net other comprehensive income	4,572
Ending Balance	(18,685)
Unrecognized Net Actuarial Loss and Prior Service Credit, Net
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(11,265)
Amounts reclassified from AOCI, net of tax	85
Net other comprehensive income	85
Ending Balance	(11,180)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(34,176)
Other comprehensive income before reclassifications	4,608
Amounts reclassified from AOCI, net of tax	69
Net other comprehensive income	4,677
Ending Balance	$ (29,499)