Employee Benefit Plans (One Percent Change in Assumed Healthcare Cost Trend Rates) (Details) - Other Postretirement Benefits U.S. Plans $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
One-percentage point change in assumed healthcare cost trend rates [Abstract]
Effect on total of service and interest costs components, one percent increase	$ 12
Effect on total of service and interest costs components, one percent decrease	(10)
Effect of accumulated postretirement benefit obligations, one percent increase	215
Effect of accumulated postretirement benefit obligations, one percent decrease	$ (178)

No definition available.

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ 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 (m)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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- Definition

The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

+ Details

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