Property and Equipment - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Earnings Per Share, Basic	$ 0.03	$ 0.14	$ 0.08	$ 0.10	$ 0.09	$ 0.08	$ (0.04)	$ (0.05)	$ 0.35	$ 0.08	$ (0.63)
Diluted earnings (loss) per share (in USD per share)	$ 0.03	$ 0.14	$ 0.08	$ 0.10	$ 0.09	$ 0.08	$ (0.04)	$ (0.05)	$ 0.35	$ 0.08	$ (0.63)
Net Income (Loss) Attributable to Parent	$ 1,499	$ 7,528	$ 4,493	$ 5,456	$ 5,047	$ 4,341	$ (2,324)	$ (2,693)	$ 18,979	$ 4,370	$ (33,063)
Depreciation									8,400	12,400	$ 11,700
Property, Plant and Equipment, Net	36,714				$ 32,656				36,714	$ 32,656
Internal Use Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Net	$ 20,800								$ 20,800
Change in Accounting Estimate, Type [Domain] | Internal Use Software [Member]
Property, Plant and Equipment [Line Items]
Earnings Per Share, Basic									$ 0.015
Diluted earnings (loss) per share (in USD per share)									$ 0.015
Net Income (Loss) Attributable to Parent									$ 800
Depreciation									$ 1,400
Useful life of property and equipment									4 years 6 months