| **Restructuring Charges and Other Costs Associated with Acquisitions and Cost-Reduction/Productivity Initiatives - Restructuring Accruals - Footnotes (Detail) - USD ($) $ in Millions**                         | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Restructuring Cost and Reserve [Line Items]**                                                                                                                                                                  |          |               |          |  |   |
| Restructuring reserve                                                                                                                                                                                            | $ 1,583       | [1]           | $ 1,157       | [2] | $ 1,166 |
| Other Current Liabilities [Member]                                                                                                                                                                               |          |               |          |  |   |
| **Restructuring Cost and Reserve [Line Items]**                                                                                                                                                                  |          |               |          |  |   |
| Restructuring reserve                                                                                                                                                                                            | 863           |               | 776           |  |   |
| Other Noncurrent Liabilities [Member]                                                                                                                                                                            |          |               |          |  |   |
| **Restructuring Cost and Reserve [Line Items]**                                                                                                                                                                  |          |               |          |  |   |
| Restructuring reserve                                                                                                                                                                                            | $ 720         |               | $ 381         |  |   |
|                                                                                                                                                                                                                  |
| [1]Included in Other current liabilities ($863 million) and Other noncurrent liabilities ($720 million).[2]Included in Other current liabilities ($776 million) and Other noncurrent liabilities ($381 million). |

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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| - Definition
Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.
+ References
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| X                                                                                                                                                                 |
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