Deferred Tax Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Deferred tax assets
Accrued liabilities and reserves	$ 86,714		$ 58,420
Postretirement benefits	79,065		82,823
Employee compensation & benefits	95,170		49,404
Tax loss and credit carryforwards	398,921		24,350
Other	53,531		4,698
Total deferred tax assets	713,401		219,695
Valuation allowance	167,640	[1]	13,242	[1]
Deferred tax assets, net of valuation allowance	545,761		206,453
Deferred tax liabilities
Property, plant and equipment	97,370		43,572
Goodwill and other intangibles	779,176		290,939
Total deferred tax liabilities	876,546		334,511
Net deferred tax liabilities	$ 330,785		$ 128,058

[1] The increase in valuation allowance from 2011 to 2012 was primarily related to balances acquired in the Merger.