Going Concern Evaluation - Additional Information (Detail) - USD ($) $ in Thousands				1 Months Ended		3 Months Ended		9 Months Ended
	Nov. 07, 2018	May 03, 2018	Mar. 05, 2018	Sep. 30, 2017	May 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Going Concern Evaluation [Line Items]
Substantial doubt about going concern, management's evaluation								In connection with preparing consolidated financial statements for the three and nine months ended September 30, 2019, management evaluated whether there were conditions and events that, when considered in the aggregate, raised substantial doubt about the Company’s ability to continue as a going concern within one year from the date that the financial statements are issued.The Company considered the historical operating loss and negative cash flow from operating activities trends, including the positive trends occurring in the recent year. Ordinarily, conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern relate to the entity’s ability to meet its obligations as they become due. The Company evaluated its ability to meet its obligations as they become due within one year from the date that the financial statements are issued by considering the following: In May 2017, the Company raised $2.2 million of new capital in a private placement offering of its common stock. In September 2017, the Company closed on a $5.5 million preferred stock transaction which converted $2.8 million of long and short-term debt and raised $2.7 million of new capital. On March 5, 2018, the Company raised $5.0 million of new capital in a private placement offering of its common stock. On May 3, 2018, the Company raised $7.0 million of new capital in a private placement offering of its common stock. On November 7, 2018, the Company raised $7.5 million of new capital in a private placement offering of its common stock. Following this transaction, $3.2 million of short and long-term debt was repaid. During the third quarter of 2019, the Company received over $11.0 million in cash as a result of warrant exercises. Management believes the Company will generate enough cash from operations to satisfy its obligations for the next twelve months from the issuance date.
Common stock raised of new capital, value							$ (10)	$ (14)	$ 10,748
Preferred stock transaction				$ 5,500
Debt instrument, principal amount				2,800
New equity capital raised				$ 2,700
Proceeds from warrant exercises						$ 11,000		$ 11,403
Substantial doubt about going concern, management's plans, substantial doubt not alleviated								The Company will take the following actions, if it starts to trend unfavorably against its internal profitability and cash flow projections, in order to mitigate conditions or events that would raise substantial doubt about its ability to continue as a going concern: Raise additional capital through a private placement. Raise additional capital through short-term loans. Implement restructuring and cost reductions. Secure a commercial bank line of credit. Sell or license intellectual property.
Private Placement [Member]
Going Concern Evaluation [Line Items]
Common stock raised of new capital, value	$ 7,500	$ 7,000	$ 5,000		$ 2,200
Repayments of debt	$ 3,200