Components of Noncurrent Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Schedule of Other Liabilities [Line Items]
Pension and retiree medical obligations	$ 94,749	$ 96,853
Liability for uncertain tax positions	4,579	4,989
Deferred revenue	6,304	6,534
Contingent consideration for acquisition		5,515
Other	14,547	14,484
Total other noncurrent liabilities	$ 120,179	$ 128,375