Summary of Significant Accounting Policies (Income Taxes ) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
U.S federal	$ 42	$ (356)	$ 462
U.S. State	297	20	11
Outside United States	44	33
Total Current	383	(303)	473
Deferred:
U.S federal	(9,734)	(8,796)	(8,952)
U.S. State	(427)	(877)	(1,586)
Total Deferred	(10,161)	(9,673)	(10,538)
Total	$ (9,778)	$ (9,976)	$ (10,065)