Pensions and Other Benefit Plans - Information Related to the Benefit Obligation and the Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2017	Jan. 01, 2017
Qualified Plans \| U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	$ 18,681	$ 16,057
Projected Benefit Obligation	19,652	16,336
Accumulated Benefit Obligation	17,654	14,759
Projected Benefit Obligation	(971)	(279)
Accumulated Benefit Obligation	1,027	1,298
Non-Qualified Plans \| U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	0	0
Projected Benefit Obligation	2,257	1,905
Accumulated Benefit Obligation	1,849	1,568
Projected Benefit Obligation	(2,257)	(1,905)
Accumulated Benefit Obligation	(1,849)	(1,568)
Funded Plans \| International Plans
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	9,723	7,576
Projected Benefit Obligation	10,863	9,502
Accumulated Benefit Obligation	9,893	8,663
Projected Benefit Obligation	(1,140)	(1,926)
Accumulated Benefit Obligation	(170)	(1,087)
Unfunded Plans \| International Plans
Defined Benefit Plan Disclosure [Line Items]
Plan Assets	0	0
Projected Benefit Obligation	449	373
Accumulated Benefit Obligation	397	329
Projected Benefit Obligation	(449)	(373)
Accumulated Benefit Obligation	$ (397)	$ (329)

Defined benefit plan funded status ABO.

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

+ Details

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

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+ Details

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

+ 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 (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919

+ Details

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