Income Taxes - Summary of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
US - State	$ (15)	$ (56)
Foreign	(63)	(22)	$ (5)
Total current	(78)	(78)	(5)
Deferred:
US - Federal	(91)	(88)	(91)
US - State	1
Total deferred	(90)	(88)	(91)
Total income tax expense	$ (168)	$ (166)	$ (96)