Fair Value Measurements - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value Disclosures [Abstract]
Hedge derivative expiration period	One-month period
Proceeds from the sales and maturities of securities available-for-sale	$ 43.4	$ 42.0	$ 27.4