Employee Benefit Plans, Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension Plans [Member]
Estimated Future Benefit Payments
2019	$ 169
2020	193
2021	175
2022	180
2023	194
2024-2028	1,043
Employee Benefit Plans (Textual)
Future employer contributions to pension and other postretirement plans	35
Other Postretirement Benefit Plans [Member]
Estimated Future Benefit Payments
2019	21
2020	21
2021	21
2022	20
2023	20
2024-2028	95
Employee Benefit Plans (Textual)
Future employer contributions to pension and other postretirement plans	$ 21

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

+ References

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-Publisher FASB
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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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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 1
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- Definition

Employee Benefit Plans, Textual [Abstract]

+ References

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