Stock-Based Compensation - Restricted Stock Activity (Details) - Restricted Stock Units - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Non-vested, beginning balance (in shares)	408,710	374,504
Shares granted (in shares)	200,000	240,000
Shares vested (in shares)	395,117	160,286
Shares forfeited (in shares)	28,333	45,508
Non-vested, ending balance (in shares)	185,260	408,710
Weighted Average Grant Date Fair Value
Weighted average grant date fair value, beginning balance (in dollars per share)	$ 2.66	$ 5.08
Shares granted (in dollars per share)	1.20	2.29
Shares vested (in dollars per share)	1.99	1.58
Shares forfeited (in dollars per share)	1.74	4.10
Weighted average grant date fair value, ending balance (in dollars per share)	$ 2.67	$ 2.66