Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits, Excluding Interest and Penalties (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning balance	$ 15,824	$ 13,804
Additions based on tax positions related to the current year	2,269	3,999
Additions for tax positions of prior years	4,375	592
Reductions for tax positions of prior years	(746)	(137)
Reductions for expiration of statutes	(269)	(610)
Settlements	(2,661)	(1,668)
Change in foreign currency exchange rates	(447)	(156)
Ending balance	$ 18,345	$ 15,824