Earnings Per Share - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share amount	200,000	300,000
Additional authorized repurchase amount	$ 68.2
Number of shares repurchased	0	241,270
Repurchase of common stock, value		$ 6.8
Treasury stock reissued, shares	15,945	106,800
Common Stock [Member]
Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share amount	200,000