Estimated Fair Values of Assets Acquired and Liabilities Assumed at Date of Acquisition (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Current assets, net of cash acquired	$ 1,365
Property, plant and equipment	205
Intangible assets	597
Goodwill	774
Total assets acquired	2,941
Current liabilities	549
Long-term debt	4
Other liabilities	83
Total liabilities	636
Cash consideration, net of cash acquired	$ 2,305

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