Common Stock and Treasury Stock - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended	27 Months Ended			1 Months Ended	3 Months Ended
	Feb. 29, 2012	Mar. 31, 2014	Dec. 31, 2011	Dec. 31, 2013	Feb. 28, 2014	Jul. 31, 2013	Sep. 13, 2012 Maximum	Mar. 31, 2014 Maximum
Maximum stock authorized to purchase under stock repurchase program	$ 262,100,000		$ 210,000,000				$ 113,000,000
Increase in maximum stock authorized to purchase under stock repurchase program	52,100,000				100,000,000	100,000,000
Stock authorized to purchase under stock repurchase program, shares							2,500,000
Repurchase of common stock, shares		1,192,809		12,369,489
Repurchase of common stock, value		70,000,000		395,800,000
Remaining value of shares authorized for purchase under the stock repurchase program								$ 138,300,000