Reconciliation of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010		Dec. 31, 2009
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Balance at beginning of period	$ 26,412	$ 59,113	[1]	$ 57,484	[1]
Increases based on tax positions taken in the current year	8,197	3,511		9,895	[1]
Increases based on tax positions taken in prior years	2,590	920		1,322	[1]
Decreases based on tax positions taken in prior years	(473)	(875)		(775)	[1]
Unrecognized tax benefits transferred to discontinued operations		(35,920)
Decreases due to settlements with tax authorities	(2,697)	(95)		(8,813)	[1]
Decreases due to lapse of applicable statute of limitation	(2,365)	(242)
Balance at end of period	$ 31,664	$ 26,412		$ 59,113	[1]

[1] 2009 amounts include discontinued operations.