Equity - Warrants (Details) - USD ($)	1 Months Ended			3 Months Ended
	May 31, 2016	Sep. 30, 2014	Sep. 30, 2012	Mar. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	May 31, 2016
Weighted Average Exercise Price Per Share
Proceeds from issuance of common stock				$ 449,000
Warrant liability					$ 935,000	$ 922,000
Warrant
Number of Underlying Shares
Outstanding, beginning balance (in shares)				17,578,950
Dilution adjustment (in shares)				32,400
Outstanding, end balance (in shares)				17,611,350
Weighted Average Exercise Price Per Share
Outstanding, beginning balance (in dollars per share)				$ 2.17
Outstanding, end balance (in dollars per share)				$ 2.17
Warrants outstanding (in shares)				17,578,950	17,611,350	17,578,950
2012 Warrants
Number of Underlying Shares
Dilution adjustment (in shares)				2,719,113
Outstanding, end balance (in shares)				6,150,762
Weighted Average Exercise Price Per Share
Outstanding, end balance (in dollars per share)				$ 4.70
Warrants outstanding (in shares)				6,150,762	6,150,762
2012 Warrants | Sentient
Number of Underlying Shares
Granted (in shares)			3,431,649
Weighted Average Exercise Price Per Share
Outstanding, end balance (in dollars per share)			$ 8.42
Number of shares of common stock per capital unit (in shares).			1
Term of warrants			5 years
Number of common shares which can be purchased with each warrant			0.5
2014 Warrants
Number of Underlying Shares
Dilution adjustment (in shares)				714,588
Outstanding, end balance (in shares)				5,460,588
Weighted Average Exercise Price Per Share
Outstanding, end balance (in dollars per share)				$ 0.87
Warrants outstanding (in shares)				5,460,588	5,460,588
2014 Warrants | Sentient
Number of Underlying Shares
Granted (in shares)		4,746,000
Weighted Average Exercise Price Per Share
Outstanding, end balance (in dollars per share)		$ 1.21
Number of shares of common stock per capital unit (in shares).		1
Term of warrants		5 years
Number of common shares which can be purchased with each warrant		0.5
Level 3 | Warrant
Weighted Average Exercise Price Per Share
Warrant liability					$ 1,900,000
Level 3 | 2012 Warrants
Weighted Average Exercise Price Per Share
Warrant liability					49,000
Level 3 | 2014 Warrants
Weighted Average Exercise Price Per Share
Warrant liability					$ 1,900,000
Registered Offering
Weighted Average Exercise Price Per Share
Common stock issued (in shares)	8,000,000
Sale price (in dollars per shares)							$ 0.50
Registered Offering | 2016 Warrants
Number of Underlying Shares
Outstanding, end balance (in shares)	6,000,000
Weighted Average Exercise Price Per Share
Granted (in dollars per share)	$ 0.75
Term of warrants	5 years
Warrants outstanding (in shares)	6,000,000						6,000,000