Expense (Benefit) for Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Federal
Current									$ 4,150	$ 1,812	$ 9,964
Deferred									6,456	12,352	(3,259)
Total									10,606	14,164	6,705
State
Current									1,649	1,685	1,415
Deferred									621	(725)	(2,356)
Total									2,270	960	(941)
Foreign
Current									5,149	6,366	6,465
Deferred									436	17	1,253
Total									5,585	6,383	7,718
Income tax provision	$ 12,106	$ 482	$ 704	$ 5,169	$ 15,254	$ 3,263	$ 2,419	$ 571	$ 18,461	$ 21,507	$ 13,482