Share-Based Compensation Summary of Information Regarding Stock Option and Restricted Stock Activity (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of stock options exercised	$ 25,520	$ 17,419	$ 20,772
Total grant date fair value of stock options vested	18,168	17,169	14,771
Restricted stock unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of restricted stock vested	14,176	12,747	9,142
Total grant date fair value of restricted stock vested	$ 10,940	$ 10,176	$ 7,240