Basis of Presentation and Summary of Significant Accounting Policies - Reconciliation of Basic and Diluted Loss per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Numerator:
Net loss	$ (1,804)	$ (3,114)	$ (4,194)	$ (7,636)
Denominator:
Basic weighted average common shares outstanding (in shares)	11,949	11,791
Weighted Average Number of Shares Outstanding, Basic and Diluted	11,949	11,791	11,925	11,755
Potential common shares from equity awards and warrants (in shares)	0	0	0	0
Diluted weighted average shares (in shares)	11,949	11,791	11,925	11,755