Net Income (Loss) Per Common and Preferred Share - Computation of Basic and Diluted Net Loss Per Common and Preferred Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Allocation of loss attributed to shareholders
Basic	$ (3,722)	$ (7,517)
Basic	$ (33)
Weighted average number of shares:
Basic	17,804,421	17,946,209
Diluted	17,804,421	17,974,469
Net loss attributable to shareholders per share - basic	$ (0.21)	$ (0.42)
Net loss attributable to shareholders per share - diluted	$ (0.21)	$ (0.43)
Common Shares [Member]
Allocation of loss attributed to shareholders
Basic	$ (3,722)	$ (7,517)
Adjustment for change in fair value of liability classified stock options		(133)
Diluted	$ (3,722)	$ (7,650)
Weighted average number of shares:
Basic	17,804,421	17,946,209
Adjustment for dilutive effect of stock options		28,260
Diluted	17,804,421	17,974,469
Net loss attributable to shareholders per share - basic	$ (0.21)	$ (0.42)
Net loss attributable to shareholders per share - diluted	$ (0.21)	$ (0.43)
Preferred Shares [Member]
Allocation of loss attributed to shareholders
Basic	$ (33)
Diluted	$ (33)
Weighted average number of shares:
Basic	159,333
Diluted	159,333
Net loss attributable to shareholders per share - basic	$ (0.21)
Net loss attributable to shareholders per share - diluted	$ (0.21)