v2.4.0.6

Employee Benefit Plans - Fair Values Of Our Pension Plan Assets (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
U.S. (Pension Benefits) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	$ 4,149	$ 3,890	$ 3,144
U.S. (Pension Benefits) [Member] | U.S. (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	1,251	1,250
U.S. (Pension Benefits) [Member] | International (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	803	818
U.S. (Pension Benefits) [Member] | Common/Collective Trusts(Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	634	635
U.S. (Pension Benefits) [Member] | Government (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	392	307
U.S. (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	554	423
U.S. (Pension Benefits) [Member] | Collateralized Mortgage Backed Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	105	81
U.S. (Pension Benefits) [Member] | Common/Collective Trusts (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	249	270
U.S. (Pension Benefits) [Member] | Private Equity Funds [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	4	6
U.S. (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	3,992	3,790
Int'l (Pension Benefits) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	2,722	2,581	2,281
Int'l (Pension Benefits) [Member] | U.S. (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	413	378
Int'l (Pension Benefits) [Member] | International (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	413	498
Int'l (Pension Benefits) [Member] | Common/Collective Trusts(Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	234	246
Int'l (Pension Benefits) [Member] | Mutual Funds (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	246	282
Int'l (Pension Benefits) [Member] | Government (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	532	390
Int'l (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	123	173
Int'l (Pension Benefits) [Member] | Collateralized Mortgage Backed Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	43
Int'l (Pension Benefits) [Member] | Common/Collective Trusts (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	346	329
Int'l (Pension Benefits) [Member] | Mutual Funds (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	130	122
Int'l (Pension Benefits) [Member] | Cash and Cash Equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	58	19
Int'l (Pension Benefits) [Member] | Private Equity Funds [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	13	8
Int'l (Pension Benefits) [Member] | Derivative [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	11	12
Int'l (Pension Benefits) [Member] | Insurance Contracts [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	15	16
Int'l (Pension Benefits) [Member] | Real Estate [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	139	101
Int'l (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	2,716	2,574
Level 1 [Member] | U.S. (Pension Benefits) [Member] | U.S. (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	1,251	1,250
Level 1 [Member] | U.S. (Pension Benefits) [Member] | International (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	803	818
Level 1 [Member] | U.S. (Pension Benefits) [Member] | Government (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	311	251
Level 1 [Member] | U.S. (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	2,365	2,319
Level 1 [Member] | Int'l (Pension Benefits) [Member] | U.S. (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	413	378
Level 1 [Member] | Int'l (Pension Benefits) [Member] | International (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	413	498
Level 1 [Member] | Int'l (Pension Benefits) [Member] | Mutual Funds (Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	246	282
Level 1 [Member] | Int'l (Pension Benefits) [Member] | Government (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	532	390
Level 1 [Member] | Int'l (Pension Benefits) [Member] | Mutual Funds (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	130	122
Level 1 [Member] | Int'l (Pension Benefits) [Member] | Cash and Cash Equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	32	9
Level 1 [Member] | Int'l (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	1,766	1,679
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Common/Collective Trusts(Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	634	635
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Government (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	81	56
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	551	420
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Collateralized Mortgage Backed Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	105	81
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Common/Collective Trusts (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	249	270
Level 2 [Member] | U.S. (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	1,620	1,462
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Common/Collective Trusts(Equity Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	234	246
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	122	171
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Collateralized Mortgage Backed Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	43
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Common/Collective Trusts (Debt Securities) [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	346	329
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Cash and Cash Equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	26	10
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Derivative [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	11	12
Level 2 [Member] | Int'l (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	782	768
Level 3 [Member] | U.S. (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	3	3
Level 3 [Member] | U.S. (Pension Benefits) [Member] | Private Equity Funds [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	4	6
Level 3 [Member] | U.S. (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	7	9
Level 3 [Member] | Int'l (Pension Benefits) [Member] | Corporate Debt Securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	1	2
Level 3 [Member] | Int'l (Pension Benefits) [Member] | Private Equity Funds [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	13	8
Level 3 [Member] | Int'l (Pension Benefits) [Member] | Insurance Contracts [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	15	16
Level 3 [Member] | Int'l (Pension Benefits) [Member] | Real Estate [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	139	101
Level 3 [Member] | Int'l (Pension Benefits) [Member] | Excluding Reconciling Items [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Fair Value of Option Plan Assets	$ 168	$ 127

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X

- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 35

-Paragraph 50

-URI http://asc.fasb.org/extlink&oid=6867990&loc=d3e12355-114930



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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 49

-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 Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph d(iv)(b)(i)

-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 FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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