Stock Options and Restricted Stock - Summary of Activity for Restricted Stock Programs (Detail) - $ / shares		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant price per share, cancelled, lower limit		$ 2.14
Grant price per share, cancelled, upper limit		$ 7.10
Restricted Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares, beginning balance		190,915		408,582	167,703
Number of shares, granted		216,148		101,010	327,251
Number of shares, cancelled		(3,946)		(9,737)	(8,988)
Number of shares, vested	[1]	(118,238)		(308,940)	(77,384)
Number of shares, ending balance		284,879	[2]	190,915	408,582
Grant price per share, lower range limit beginning balance		$ 2.14		$ 2.06	$ 3.95
Grant price per share, upper range limit beginning balance		5.27		10.38	13.46
Grant price per share, granted, lower limit		4.80		3.93	2.06
Grant price per share, granted, upper limit		7.25		5.27	3.93
Grant price per share, cancelled, lower limit		3.93		3.93	2.14
Grant price per share, cancelled, upper limit		6.55		9.08	10.08
Grant price per share, vested, lower limit	[1]	2.06		2.06	9.08
Grant price per share, vested, upper limit	[1]	4.80		10.38	13.46
Grant price per share, lower range limit ending balance		3.95	[2]	2.14	2.06
Grant price per share, upper range limit ending balance		7.25	[2]	5.27	10.38
Weighted average grant price beginning balance		4.06		3.45	8.88
Weighted average grant price, granted		6.59		4.41	2.48
Weighted average grant price, cancelled		4.97		4.66	3.07
Weighted average grant price, vested	[1]	3.89		3.35	11.09
Weighted average grant price, ending balance		$ 6.01	[2]	$ 4.06	$ 3.45

[1] The aggregate fair value of the restricted stock vested was $736,000, $1,270,000, and $169,000 for 2019, 2018, and 2017.

[2] The aggregate fair value of the restricted stock was $2,071,000 as of December 31, 2019. The remaining vesting period was 3.07 years at December 31, 2019.