Summary of Significant Accounting Policies - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Inventory, Raw Materials, Net of Reserves	$ 148	$ 164
Inventory, Finished Goods, Net of Reserves	2,422	2,729
Inventory, Net	$ 2,570	$ 2,893