Pensions and Other Employee Benefits - Estimated Future Benefit Payments (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2014	$ 116
2015	125
2016	134
2017	146
2018	152
Years 2019-2023	925
Postretirement Benefit Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2014	13
2015	13
2016	14
2017	14
2018	15
Years 2019-2023	77
Subsidy Receipts, 2014
Subsidy Receipts, 2015
Subsidy Receipts, 2016
Subsidy Receipts, 2017
Subsidy Receipts, 2018
Subsidy Receipts, Years 2019-2023	$ 1

Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of the prescription drug subsidy receipts to be received after the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Section 50

-Paragraph 4

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Amount of the prescription drug subsidy receipts to be received in the next fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the fifth fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the fourth fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the third fiscal year following the latest fiscal year.

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Amount of the prescription drug subsidy receipts to be received in the second fiscal year following the latest fiscal year.

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