Components of the Provision for Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Tax provision:
Federal	$ 326,708	$ 219,124	$ 195,843
State	38,931	28,260	25,492
Foreign	13,461	9,958	8,167
Current Income Tax Expense (Benefit), Total	379,100	257,342	229,502
Deferred provision (benefit):
Federal	(11,674)	4,781	4,397
State	(1,334)	546	503
Foreign	(1,434)	423	2,674
Deferred provision (benefit):	(14,442)	5,750	7,574
Total provision	$ 364,658	$ 263,092	$ 237,076