Employee Benefit Plans (Expected Gross Benefit Payments) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2019	$ 620
2020	636
2021	643
2022	661
2023	682
2024-2028	3,596
Other Postretirement Benefits
Defined benefit plan estimated future benefit payments [Abstract]
2019	85
2020	83
2021	81
2022	82
2023	84
2024-2028	$ 413

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- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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- Definition

Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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