Summary of Restricted Stock Award Activity (Parenthetical) (Detail) - Restricted Stock Awards (RSAs) [Member] - USD ($)	1 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2016	[1]	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, Restricted stock awards		65,000	117,553		181,783	0
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, Restricted stock awards	71,925
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants, Restricted stock awards	89,906
Stock-based compensation related to grants	$ 4,400,000

[1] In September 2016, the Company granted executives RSAs with certain sales targets. If the sales targets are achieved within the required time frame, the number of RSAs may be increased from 71,925 to 89,906 shares. If and when deemed probable that such performance milestones may be achieved within the required time frame, the Company may recognize up to $4.4 million of stock-based compensation related to these grants.