Components Of Accumulated Other Comprehensive Income or Loss (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation adjustments	$ 11,846	$ 5,875
Funded status of pension plans and other postretirement benefits, net of tax	(67,239)	(67,239)
Unrealized gain (loss) on derivative instruments, net of tax	(15)	(270)
Unrealized gain (loss) on marketable securities, net of tax		(1,168)
Accumulated other comprehensive income (loss)	$ (55,408)	$ (62,802)