Stock Options and Restricted Stock - Summary of Activity for Stock Option Programs (Detail) - $ / shares		3 Months Ended				12 Months Ended
		Sep. 30, 2018		Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options beginning balance		129,666		320,626	320,626	345,518
Granted		15,000		24,000		29,666
Cancelled				(214,960)		(54,558)
Exercised	[1]	0		0	0	0
Number of options ending balance		144,666	[2]	129,666	320,626	320,626
Options exercisable at September 30, 2018	[2]	79,778
Exercise price per share, lower range limit beginning balance		$ 2.14		$ 2.14	$ 2.14	$ 7.10
Exercise price per share, upper range limit beginning balance		13.84		13.84	13.84	13.84
Exercise price per share, granted		5.27		5.58
Exercise price per share, exercised	[1]			0
Exercise price per share, lower range limit ending balance		2.14	[2]	2.14	2.14	2.14
Exercise price per share, upper range limit ending balance		13.84	[2]	13.84	13.84	13.84
Exercise price per share, option exercisable lower range limit	[2]	2.22
Exercise price per share, option exercisable upper range limit	[2]	13.84
Weighted average exercise price, beginning balance		7.45		8.78	8.78	9.67
Weighted average exercise price, granted		5.27		5.58		2.35
Weighted average exercise price, cancelled				9.22		10.94
Weighted average exercise price, exercised	[1]	0		0	0	0
Weighted average exercise price, ending balance		7.23	[2]	7.45	$ 8.78	8.78
Weighted average exercise price, options exercisable	[2]	$ 9.44
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price per share, granted						2.14
Exercise price per share, cancelled				9.22		10.76
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price per share, granted						2.61
Exercise price per share, cancelled				$ 9.24		$ 11.21

[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 and $0 for the 2018 and 2017 third quarter and nine months.

[2] The aggregate intrinsic value, which represents the difference between the price of the Company's common stock at September 30, 2018 and the related exercise price of the underlying options, was $174,000 for outstanding options and $33,000 for exercisable options as of September 30, 2018. The remaining contractual life was 7.22 years for outstanding options and 5.51 years for exercisable options at September 30, 2018.