Basic and Diluted Weighted Average Shares Outstanding (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Weighted Average Number of Shares Outstanding [Line Items]
Weighted average common shares	33,779,141	32,925,004	33,485,448	32,860,382
Dilutive common stock options	533,746	764,556	526,086	757,617
Weighted average common shares, assuming dilution	34,312,887	33,689,560	34,011,534	33,617,999