Pension and Postretirement Benefit Plans and Defined Contribution Plans - Pension Plans in Excess of Plan Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
U.S. Qualified Pension Plans [Member]
Pension plans with an accumulated benefit obligation in excess of plan assets:
Fair value of plan assets	$ 11,633	$ 12,706
Accumulated benefit obligation	14,755	16,323
Pension plans with a projected benefit obligation in excess of plan assets:
Fair value of plan assets	11,633	12,706
Projected benefit obligation	14,926	16,575
U.S. Supplemental (Non-Qualified) Pension Plans [Member]
Pension plans with an accumulated benefit obligation in excess of plan assets:
Accumulated benefit obligation	1,324	1,447
Pension plans with a projected benefit obligation in excess of plan assets:
Projected benefit obligation	1,343	1,481
International Pension Plans [Member]
Pension plans with an accumulated benefit obligation in excess of plan assets:
Fair value of plan assets	976	1,718
Accumulated benefit obligation	2,495	4,021
Pension plans with a projected benefit obligation in excess of plan assets:
Fair value of plan assets	1,546	1,999
Projected benefit obligation	$ 3,373	$ 4,715

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=58242635&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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- References

No definition available.

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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