Defined Benefit Plan Employee Vesting Period

No definition available.

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

+ References

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- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

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- Definition

The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520743

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Plan Amendment

-URI http://asc.fasb.org/extlink&oid=6520782

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(7)

-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 during the next fiscal year beginning after the date of the latest statement of financial position.

+ References

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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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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

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Employee Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Qualified employees maximum contribution to defined contribution savings plan allowed in percentage of annual compensation	75.00%
Company contribution to defined savings plan	4.00%
Company contribution, percentage company contribution matches of the employee's percentage contribution matched	100.00%
Employee retirement savings plan matching expenses	$ 122	$ 118	$ 111
Vesting service period for defined benefit pension plan	3 years
Plan assets of the qualified pension plans that have asset management arrangements with related parties	70	119
Passive Global Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	35.00%
Active Global Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	8.00%
Mid Small Cap Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	7.00%
Emerging Markets Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	5.00%
Real Estate Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	5.00%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	30.00%
Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	5.00%
Private Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocation for the company's qualified pension plan	5.00%
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions to pension and postretirement welfare plan	475	296
Non Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions to pension and postretirement welfare plan	21
Postretirement Welfare Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Company contributions to pension and postretirement welfare plan	7	1
Company contributions to pension and postretirement welfare plan	7
Decrease in Postretirement Welfare Plan Benefit Obligation Due To Plan Amendment		$ (35)