Stockholder's Equity - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended	0 Months Ended
	Dec. 03, 2012	Dec. 31, 2013	Dec. 31, 2013	Oct. 16, 2012 Maximum [Member]
Shareholders Equity [Line Items]
Special dividend, per outstanding common share	$ 2.50
Special dividend	$ 486,141,000
Special dividends record date		Nov. 16, 2012
Share buyback program, authorization				1,000,000,000
Shares repurchased, value			$ 750,000,000
Shares repurchased, shares			11,722,969