Intangible Assets - Estimated Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intangible Assets.
Amortization of Intangible Assets	$ 590	$ 981	$ 2,391
Estimated amortization expense
2016	568
2017	568
2018	461
2019	425
2020	425
Thereafter	1,486
Total	$ 3,933	$ 4,644