Equity Transactions - Additional Information (Detail)									1 Months Ended	12 Months Ended
	Nov. 07, 2018 USD ($) $ / shares shares	May 03, 2018 USD ($) $ / shares shares	Apr. 19, 2018 USD ($)	Mar. 06, 2018 USD ($) $ / shares shares	Sep. 29, 2017 USD ($) $ / shares shares	May 17, 2017 USD ($) shares	May 16, 2017 Investor $ / shares shares	Sep. 06, 2016 USD ($) $ / shares	Sep. 30, 2017 USD ($)	Dec. 31, 2018 USD ($) Triggering_Event $ / shares shares	Dec. 31, 2017 USD ($) shares	May 31, 2017 $ / shares	Sep. 02, 2016 USD ($) $ / shares shares
Class of Stock [Line Items]
Preferred stock, issued and sold to investors, purchase price									$ 5,500,000
Gross proceeds from issuance of preferred stock									2,700,000
Debt instrument, principal amount									$ 2,800,000
Net proceeds from issuance of preferred stock											$ 2,413,000
Repayment of short and long-term debt obligations	$ 3,200,000
Number of triggering events for issuance of warrants | Triggering_Event										5
Common Stock [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares										9,267,000	2,162,000
Warrant [Member]
Class of Stock [Line Items]
Triggering event charges										$ 3,000
Unterberg Koller Capital Fund L P [Member]
Class of Stock [Line Items]
Adjusted exercise price | $ / shares										$ 2.14
Investors [Member] | Note and Warrant Purchase Agreement [Member]
Class of Stock [Line Items]
Common stock exercise price | $ / shares													$ 2.74
Warrants expiration period										5 years
Purchase of warrants | shares													1,700,000
Notes and warrants issuance date										Sep. 06, 2016
Investors [Member] | Note and Warrant Purchase Agreement [Member] | Senior Subordinated Notes [Member]
Class of Stock [Line Items]
Debt instrument, principal amount													$ 4,000,000
Smith Warrant [Member]
Class of Stock [Line Items]
Adjusted exercise price | $ / shares										$ 2.38
Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, conversion price per share | $ / shares					$ 1.14					$ 1.14
Convertible preferred stock, terms of conversion										In the event that the trading price of the Company’s Common Stock for 20 consecutive trading days (as determined in the Certificate of Designation) exceeds 400% of the then effective Conversion Price of the Series B Preferred Stock (initially set at $1.14), the Company may force conversion of the Series B Preferred Stock into shares of Common Stock or elect to redeem the Series B Preferred Stock for cash.
Preferred stock threshold consecutive trading days					20 days
Trading price of common stock exceeds conversion price, percentage					400.00%
Convertible preferred stock, right to increase in dividend percentage upon stock price trigger					12.00%
Triggering event charges										$ 41,000
Series B Preferred Stock [Member] | Andrew Arno [Member]
Class of Stock [Line Items]
Preferred stock, shares converted into common stock | shares					50
Series B Preferred Stock [Member] | Smith Warrant [Member]
Class of Stock [Line Items]
Preferred stock, shares converted into common stock | shares					2,750
Offering [Member]
Class of Stock [Line Items]
Gross proceeds from issuance of preferred stock					$ 2,700,000
Net proceeds from issuance of preferred stock					2,500,000
Preferred stock liquidation damage payments			$ 48,000
Offering [Member] | Andrew Arno [Member]
Class of Stock [Line Items]
Debt instrument, principal amount					100,000
Offering [Member] | Smith Warrant [Member]
Class of Stock [Line Items]
Debt instrument, principal amount					$ 2,800,000
Offering [Member] | Series B Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, issued and sold to investors | shares					5,500
Preferred stock, dividend rate					10.00%
Preferred stock, price per share | $ / shares					$ 1,000
Preferred stock, issued and sold to investors, purchase price					$ 5,500,000
Preferred stock, conversion price per share | $ / shares					$ 1.14
Preferred stock, shares converted into common stock | shares					4,824,562
Preferred stock, dividend payment terms										The holders of Series B Preferred Stock are entitled to receive cumulative dividends out of funds legally available thereof at a rate of ten percent (10%) per annum, payable (i) when and as declared by the Board of Directors, in quarterly installments on March 1, June 1, September 1 and December 1, (ii) upon conversion into Common Stock with respect the Series B Preferred Stock being converted, and (iii) upon redemption of the Series B Preferred Stock by the Company.
May 2017 Offerings [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares							85,000
Common stock, price per share | $ / shares							$ 1.10
Number of accredited investors | Investor							4
Gross proceeds before deducting transaction fees and other expenses						$ 2,300,000
Offering cost related to the transaction						200,000
Transaction fees						100,000
Legal and other expenses						100,000
Cash proceeds from issuance of common stock, net of offering costs						$ 2,100,000
Warrants term										5 years
Warrants exercisable beginning date										Nov. 18, 2017
Registered Direct Offering [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares						2,077,000
Sutter [Member]
Class of Stock [Line Items]
Percentage of warrants to purchase shares of common stock on number of shares sold										5.00%
Common stock exercise price | $ / shares										$ 1.21
Common stock offering price per share | $ / shares												$ 1.10
Chardan Capital Markets, LLC [Member]
Class of Stock [Line Items]
Percentage of warrants to purchase shares of common stock on number of shares sold				3.00%						5.00%
Common stock exercise price | $ / shares				$ 2.365						$ 1.155
Warrants term				5 years 6 months
Percentage of gross proceeds of offering	6.00%	7.00%		8.00%
Common stock offering price per share | $ / shares												$ 1.05
March 2018 Offering [Member]
Class of Stock [Line Items]
Gross proceeds before deducting transaction fees and other expenses				$ 5,000,000
Cash proceeds from issuance of common stock, net of offering costs				$ 4,500,000
March 2018 Offering [Member] | Common Stock [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares				2,857,144
Common stock, price per share | $ / shares				$ 1.75
Common stock exercise price | $ / shares				$ 2.17
March 2018 Offering [Member] | Warrant [Member]
Class of Stock [Line Items]
Triggering event charges								$ 11,000
March 2018 Offering [Member] | Unterberg Koller Capital Fund L P [Member] | Maximum [Member]
Class of Stock [Line Items]
Common stock exercise price | $ / shares								$ 2.14
March 2018 Offering [Member] | Unterberg Koller Capital Fund L P [Member] | Minimum [Member]
Class of Stock [Line Items]
Common stock exercise price | $ / shares								$ 2.07
May 2018 Offering [Member]
Class of Stock [Line Items]
Gross proceeds before deducting transaction fees and other expenses		$ 7,000,000
Cash proceeds from issuance of common stock, net of offering costs		$ 6,300,000
May 2018 Offering [Member] | Roth Capital Partners, LLC [Member]
Class of Stock [Line Items]
Percentage of gross proceeds of offering		2.00%
May 2018 Offering [Member] | Common Stock [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares		3,170,000
Common stock, price per share | $ / shares		$ 2.21
Common stock exercise price | $ / shares		$ 2.11
November 2018 Offering [Member]
Class of Stock [Line Items]
Gross proceeds before deducting transaction fees and other expenses	$ 7,500,000
Cash proceeds from issuance of common stock, net of offering costs	$ 6,900,000
November 2018 Offering [Member] | Roth Capital Partners, LLC [Member]
Class of Stock [Line Items]
Percentage of gross proceeds of offering	2.00%
November 2018 Offering [Member] | Common Stock [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares	3,239,785
Common stock, price per share | $ / shares	$ 2.32
Common stock exercise price | $ / shares	$ 2.20
Private Placement [Member]
Class of Stock [Line Items]
Repayment of short and long-term debt obligations	$ 3,200,000
Private Placement [Member] | Andrew Arno [Member]
Class of Stock [Line Items]
Common stock, issued and sold to investors | shares							50,000
Common stock, price per share | $ / shares							$ 1.10