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Employee Benefit Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2012 Employees | Dec. 31, 2011 | Dec. 31, 2010
Expenses for defined-contribution plans | $ 82 | $ 54 | $ 41
Number of U.S retirees and spouses participate in defined benefit health care plans | 1,105 |  |
Number of U.S. employees participate in defined benefit health care plans | 232 |  |
Net periodic benefit cost | 10 | 14 | 10
Defined Benefit Plan, Expected Future Benefit Payments in Year Five | 32 |  |
Expected years of Defined Benefit Plans. | 5 years |  |
Expected future benefit amounts to pay, total | $ 326 |  |

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- Definition Defined Benefit Plan Estimated Future Employer Contributions. + References No definition available. + Details
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- Definition Defined benefit plan number of United States employees participate in defined benefit health care plans. + References No definition available. + Details
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- Definition Number of U.S. retirees and spouses participate in defined benefit health care plans. + References No definition available. + Details
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- Definition Expected years of Defined Benefit Plans. + References No definition available. + Details
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- Definition Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph h -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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 11 -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. + Details
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