Estimated amortization of unrecognized net actuarial losses for next fiscal year.

No definition available.

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- Definition

Estimated pension and postretirement medical expense for next fiscal year.

+ References

No definition available.

+ Details

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- Definition

Maximum age to qualify for post retirement medical benefits.

+ References

No definition available.

+ Details

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- Definition

Minimum age to qualify for post retirements medical benefits.

+ References

No definition available.

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- Definition

Net asset value per fund share related to short term investment funds.

+ References

No definition available.

+ Details

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

-URI http://asc.fasb.org/extlink&oid=6503844

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ 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 (d)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (c)(i)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e2446-114920

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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

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Retirement Plans - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Age of qualified retirees, minimum	55 years
Age of qualified retirees, maximum	65 years
Estimated pension and postretirement medical expense for 2015	$ 80
Estimated amortization of unrecognized net actuarial losses for 2015	75
Net asset value per fund share related to short-term investment funds	$ 1
Budgeted contributions to funded pension plans in 2015	55
Expense related to contribution for several defined contribution plans	32	41	40
Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	50.00%
Fixed income securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	25.00%
Other types of investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	25.00%
Funded Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for the defined benefit pension plans	2,325	1,873
Unfunded Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for the defined benefit pension plans	$ 214	$ 222