Income Taxes (Provision for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current tax expense:
Federal	$ 312	$ 4,208	$ 2,256
State	159	1,238	516
Foreign	7,111	6,949	11,995
Current income tax expense (benefit)	7,582	12,395	14,767
Deferred income tax expense (benefit)	(2,871)	2,251	(284)
Provision for income taxes	$ 4,711	$ 14,646	$ 14,483