Stockholders' Equity and Share-Based Compensation - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended		9 Months Ended
	Aug. 07, 2014	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Feb. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized total share-based compensation costs		$ 3,844,000	$ 3,266,000	$ 11,601,000	$ 9,123,000
Cash dividend declared per share	$ 0.2625
Dividend date of record				Sep. 15, 2014
Dividend date of declared		2014-08		2014-08
Dividend payment date				Sep. 30, 2014
Dividend paid in cash				8,800,000
Authorization of common stock repurchase						50,000,000
Number of shares repurchased		175,800		252,500	48,100
Cost of shares repurchased		11,500,000		16,039,000	2,751,000
Cost of shares repurchased, contractual amount				16,700,000
Share-Based Compensation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for share-based compensation awards				4 years
Total unrecognized share-based compensation cost which is expected to be recognized		$ 27,800,000		$ 27,800,000
Total compensation cost not yet recognized, period for recognition				3 years