Other Noncurrent Liabilities (Components of Noncurrent Liabilities) (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Other Liabilities Disclosure [Abstract]
Pension and retiree medical obligations	$ 83,128	$ 76,190
Liability for uncertain tax positions	2,623	4,252
Deferred revenue	3,258	3,763
Other	19,253	18,160
Total other noncurrent liabilities	$ 108,262	$ 102,365