Acquisitions - Estimated Fair Values of Assets Acquired and Liabilities (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Goodwill	$ 8,997	$ 7,172
All Other Acquisitions [Member]
Business Acquisition [Line Items]
Current assets, net of cash acquired	446
Property, plant and equipment	198
Intangible assets	969
Goodwill	1,538
Other assets	25
Total assets acquired	3,176
Current liabilities	190
Deferred taxes	491
Other liabilities	120
Total liabilities	801
Cash consideration, net of cash acquired	$ 2,375

Business Acquisition Purchase Price Allocation Intangible Assets

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Amount of assets acquired at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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