Stock Option Activity (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding stock options, Beginning balance	38,092
Stock options granted during the period	51
Stock options assumed in acquisitions during the period	1,121
Stock options exercised during the period	(13,707)	[1]
Stock options cancelled/forfeited during the period	(1,198)
Stock options expired during the period	(3,391)
Outstanding stock options, Ending balance	20,968		38,092
Vested and expected to vest, outstanding, balance	19,701	[2]
Exercisable at December 31, 2013	10,696
Weighted average exercise price of options outstanding, Beginning balance	$ 21.42
Weighted-average exercise price of shares granted during period	$ 29.32
Weighted-average exercise price of shares assumed in acquisitions during period	$ 7.39
Weighted-average exercise price of shares exercised during period	$ 20.32	[1]
Weighted-average exercise price of shares cancelled/forfeited during period	$ 15.13
Weighted-average exercise price of shares expired during period	$ 29.73
Weighted average exercise price of options outstanding, Ending balance	$ 20.43		$ 21.42
Vested and expected to vest, weighted average exercise price	$ 20.13	[2]
Exercisable at December 31, 2013, weighted average exercise price	$ 22.24
Outstanding at December 31, weighted average remaining contractual life, years	4 years 2 months 12 days		4 years 2 months 9 days
Vested and expected to vest, weighted average remaining contractual life, years	4 years 1 month 2 days	[2]
Vested and expected to vest, exercisable, weighted average remaining contractual life, years	2 years 7 months 21 days
Aggregate intrinsic value, outstanding, Beginning balance	$ 78,387
Aggregate intrinsic value, outstanding, Ending balance	428,414		78,387
Vested and expected to vest, aggregate intrinsic value	400,054	[2]
Exercisable at December 31, 2013	$ 194,676

[1] The Company issued new shares to satisfy stock option exercises.

[2] The expected to vest options are the result of applying the pre-vesting forfeiture rate assumptions to total outstanding options.