Summary of Significant Accounting Policies - Revised Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheet
Other long-term liabilities	$ 12,938	$ 5,709
Deferred income taxes	7,753	439
Total liabilities	99,692	74,108
Accumulated other comprehensive Income (loss)	(8,568)	(12,910)	$ (8,686)	$ (4,842)
Total stockholders' equity	237,930	253,162
Total liabilities and stockholders' equity	$ 337,622	327,270
As Previously Reported
Consolidated Balance Sheet
Other long-term liabilities		1,878
Deferred income taxes		853
Total liabilities		70,691
Accumulated other comprehensive Income (loss)		(9,493)	(5,794)	(2,502)
Total stockholders' equity		256,579
Total liabilities and stockholders' equity		327,270
Adjustment
Consolidated Balance Sheet
Other long-term liabilities		3,831
Deferred income taxes		(414)
Total liabilities		3,417
Accumulated other comprehensive Income (loss)		(3,417)	$ (2,892)	$ (2,340)
Total stockholders' equity		$ (3,417)