Stock Repurchase Program - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended	1 Months Ended
	Sep. 30, 2014	Oct. 31, 2013 Maximum [Member]
Equity, Class of Treasury Stock [Line Items]
Amount authorized for share repurchase program		$ 100
Number of common stock shares repurchased	274,726
Repurchase of common stock	11.2
Total number of common stock shares repurchased	298,626
Total repurchase of common stock	$ 12.2