Other Noncurrent Liabilities (Components of Noncurrent Liabilities) (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Other Liabilities Disclosure [Abstract]
Pension and retiree medical obligations	$ 86,182	$ 76,190
Liability for uncertain tax positions	3,518	4,252
Deferred revenue	2,041	3,763
Other	15,772	18,160
Total other noncurrent liabilities	$ 107,513	$ 102,365