Financial Instruments - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Assets
Fair Value	$ 6,503	$ 5,069
Derivative assets	586	755
Liabilities
Derivative liabilities	180	108
Commercial paper [Member]
Assets
Fair Value	168	1,029
Corporate notes and bonds [Member]
Assets
Fair Value	3,705	2,032
U.S. government and agency securities [Member]
Assets
Fair Value	1,156	1,021
Asset-backed securities [Member]
Assets
Fair Value	648	292
Mortgage-backed securities [Member]
Assets
Fair Value	334	223
Foreign government bonds [Member]
Assets
Fair Value	72	72
Equity securities [Member]
Assets
Fair Value	420	397
Other debt securities [Member]
Assets
Fair Value		3
Fair Value, Measurements, Recurring [Member]
Assets
Investments	6,317	4,899
Securities held for employee compensation	186	170
Purchased currency options	541	613
Derivative assets	586	755
Total assets	7,089	5,824
Liabilities
Total liabilities	180	108
Fair Value, Measurements, Recurring [Member] \| Commercial paper [Member]
Assets
Fair Value	168	1,029
Fair Value, Measurements, Recurring [Member] \| Foreign exchange contract [Member]
Assets
Derivative assets	45	142
Liabilities
Derivative liabilities	176	107
Fair Value, Measurements, Recurring [Member] \| Written currency options [Member]
Liabilities
Derivative liabilities	4	1
Fair Value, Measurements, Recurring [Member] \| Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Assets
Investments	209	205
Securities held for employee compensation	186	170
Total assets	395	375
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Investments	6,108	4,694
Purchased currency options	541	613
Derivative assets	586	755
Total assets	6,694	5,449
Liabilities
Total liabilities	180	108
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Commercial paper [Member]
Assets
Fair Value	168	1,029
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Foreign exchange contract [Member]
Assets
Derivative assets	45	142
Liabilities
Derivative liabilities	176	107
Fair Value, Measurements, Recurring [Member] \| Significant Other Observable Inputs (Level 2) [Member] \| Written currency options [Member]
Liabilities
Derivative liabilities	4	1
Fair Value, Measurements, Recurring [Member] \| Corporate notes and bonds [Member]
Assets
Fair Value	3,705	2,032
Fair Value, Measurements, Recurring [Member] \| Corporate notes and bonds [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	3,705	2,032
Fair Value, Measurements, Recurring [Member] \| U.S. government and agency securities [Member]
Assets
Fair Value	1,156	1,021
Fair Value, Measurements, Recurring [Member] \| U.S. government and agency securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	1,156	1,021
Fair Value, Measurements, Recurring [Member] \| Asset-backed securities [Member]
Assets
Fair Value	648	292
Fair Value, Measurements, Recurring [Member] \| Asset-backed securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	648	292
Fair Value, Measurements, Recurring [Member] \| Mortgage-backed securities [Member]
Assets
Fair Value	334	223
Fair Value, Measurements, Recurring [Member] \| Mortgage-backed securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	334	223
Fair Value, Measurements, Recurring [Member] \| Foreign government bonds [Member]
Assets
Fair Value	72	72
Fair Value, Measurements, Recurring [Member] \| Foreign government bonds [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	72	72
Fair Value, Measurements, Recurring [Member] \| Equity securities [Member]
Assets
Fair Value	234	227
Fair Value, Measurements, Recurring [Member] \| Equity securities [Member] \| Quoted Prices In Active Markets for Identical Assets (Level 1) [Member]
Assets
Fair Value	209	205
Fair Value, Measurements, Recurring [Member] \| Equity securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value	25	22
Fair Value, Measurements, Recurring [Member] \| Other debt securities [Member]
Assets
Fair Value		3
Fair Value, Measurements, Recurring [Member] \| Other debt securities [Member] \| Significant Other Observable Inputs (Level 2) [Member]
Assets
Fair Value		$ 3

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- Definition

Securities held for employee compensation fair value disclosure.

+ References

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

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- Definition

Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 205G

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44C

-Subparagraph a

-Clause 1

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (a),(c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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- Definition

Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position.

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph a, f, g

-Article 7

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

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-Topic 320

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-Section 35

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- Definition

This element represents the aggregate of the liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

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