Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Expense (Benefit) [Abstract]
Current federal tax expense (benefit)	$ 227	$ (555)	$ 325
Deferred federal income tax expense (benefit)	3,197	(94)	(623)
Federal income tax expense (benefit), continuing operations	3,424	(649)	(298)
Current state and local tax expense (benefit)	144	120	(2)
Deferred state and local income tax expense (benefit)	457	765	1,036
State and local income tax expense (benefit), continuing operations	601	885	1,034
Current foreign tax expense (benefit)	2,770	295	1,640
Deferred foreign income tax expense (benefit)	(1,248)	(118)	(1,092)
Foreign income tax expense (benefit), continuing operations	1,522	177	548
Current income tax expense (benefit)	3,141	(140)	1,963
Deferred income tax expense (benefit)	2,406	553	(679)
Net income tax expense	$ 5,547	$ 413	$ 1,284