Taxes - Constituents of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 14,459	$ 16,430	$ 18,852
State	(617)	378	608
Foreign	8,149	4,946	4,854
Current income tax expense (benefit), Total	21,991	21,754	24,314
Deferred:
Federal	(3,031)	(2,541)	(2,569)
State	1,066	(165)	7
Foreign	(1,058)	250	(837)
Deferred income tax expense (benefit), Total	(3,023)	(2,456)	(3,399)
Income tax expense (benefit), continuing operations, Total	$ 18,968	$ 19,298	$ 20,915