Consolidated Statements of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income	$ 330,127	$ 420,197	$ 329,417
Non-cash charges associated with restructuring and other, net	61,809
Pension and postretirement expense	77,442	97,207	33,898
Deferred income taxes	(14,587)	(11,198)	42,136
As Previously Reported
Cash flows from operating activities:
Net income	350,340	464,363	337,359
Non-cash charges associated with restructuring and other, net	68,317
Pension and postretirement expense	39,418	27,161	20,993
Deferred income taxes	(3,284)	14,682	47,099
Effect of Accounting Change
Cash flows from operating activities:
Net income	(20,213)	(44,166)	(7,942)
Non-cash charges associated with restructuring and other, net	(6,508)
Pension and postretirement expense	38,024	70,046	12,905
Deferred income taxes	$ (11,303)	$ (25,880)	$ (4,963)