Stock Options and Restricted Stock - Summary of Activity for Stock Option Programs (Detail) - $ / shares		3 Months Ended			6 Months Ended		12 Months Ended
		Jun. 30, 2019		Mar. 31, 2019	Jun. 30, 2019		Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options beginning balance		501,043		144,666	144,666		320,626
Granted		1,104		374,377			39,000
Cancelled		(3,433)		(18,000)			(214,960)
Exercised	[1]	0		0			0
Number of options ending balance		498,714	[2]	501,043	498,714	[2]	144,666
Options exercisable	[2]	77,889			77,889
Exercise price per share, lower range limit beginning balance		$ 2.14		$ 2.06	$ 2.06		$ 2.14
Exercise price per share, upper range limit beginning balance		13.84		13.84	13.84		13.84
Exercise price per share, granted		6.55
Exercise price per share, exercised	[1]	0		0			0
Exercise price per share, lower range limit ending balance		2.14	[2]	2.14	2.14	[2]	2.06
Exercise price per share, upper range limit ending balance		13.84	[2]	13.84	13.84	[2]	13.84
Exercise price per share, option exercisable lower range limit	[2]	2.14			2.14
Exercise price per share, option exercisable upper range limit	[2]	13.84			13.84
Weighted average exercise price, beginning balance		6.63		7.23	7.23		8.78
Weighted average exercise price, granted				6.48	6.55		5.46
Weighted average exercise price, cancelled				8.44	7.10		9.22
Weighted average exercise price, exercised	[1]			0	0		0
Weighted average exercise price, ending balance		6.62	[2]	6.63	6.62	[2]	7.23
Weighted average exercise price, options exercisable	[2]	8.63			$ 8.63
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price per share, granted				5.21			5.27
Exercise price per share, cancelled		6.55		7.49			9.22
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price per share, granted				6.55			5.58
Exercise price per share, cancelled		$ 7.49		$ 9.38			$ 9.24

[1] The aggregate intrinsic value, which represents the difference between the price of the Company’s common stock at the exercise date and the related exercise price of the underlying options, was $0 for each of the 2019 and 2018 second quarter and six months.

[2] The aggregate intrinsic value, which represents the difference between the price of the Company’s common stock at June 30, 2019 and the related exercise price of the underlying options, was $277,000 for outstanding options and $71,000 for exercisable options as of June 30, 2019. The remaining contractual life was 9.06 years for outstanding options and 6.11 years for exercisable options at June 30, 2019.