Statements of Cash Flows (Parenthetical) - USD ($)						12 Months Ended
	Dec. 08, 2017	Aug. 09, 2017	Mar. 31, 2017	Oct. 19, 2016	May 04, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Financed insurance premium through third party financing						$ 451,000	$ 547,000
Cancellation of insurance premiums partial amount received							3,933
Fixed assets purchased under capital lease obligations						719,000	975,000
Fixed assets with an aggregate net book value						34,000	270,000
Equipment financing obligations with remaining outstanding balances							240,000
Purchases of fixed assets						$ 31,000	$ 58,000	$ 64,000
Issuance of unregistered warrants to purchase shares of common stock	246,250	1,434,639	2,160,000		1,163,526
Exercise price of unregistered warrants	$ 0.85	$ 1.50	$ 2.50		$ 3.90
Unregistered warrants to purchase common stock, period	5 years	5 years	5 years		5 years
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value	$ 100,000	$ 1,500,000	$ 2,800,000	$ 5,200,000	$ 2,000,000
Offering fees and costs recorded within common stock issuance costs as an offset to additional paid in capital	$ 428,000	$ 176,000	$ 728,000	$ 1,037,000,000,000	$ 653,000
Estimated grant date fair value of warrants				$ 0.57
Overallotment issued to underwriter to purchase common stock, period				30 days
Purchase of common stock by underwriters to cover overallotments, per share				$ 1.0331
Purchase of common stock by underwriters to cover overallotments, number of shares				627,131
Common stock, par value				$ 0.0009		$ 0.0001	$ 0.0001
Grant date fair values of overallotment options				$ 800,000
Class of warrant or rights, first exercisable date	Jun. 05, 2018
Class of warrant or rights, expiration date	Dec. 05, 2022
Maximum [Member]
Issuance of overallotment options to purchase common stock shares				1,365,000
Purchase of common stock by underwriters to cover overallotments, number of shares				1,365,000
Roth Capital Partners, LLC and Feltl [Member]
Issuance of unregistered warrants to purchase shares of common stock				9,100,000