Benefit Plans and Other Postretirement Benefits, Projected Benefit Payments (Details) $ in Millions	Dec. 31, 2018 USD ($)
Pension Plan [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2019	$ 281
2020	260
2021	259
2022	260
2023	259
2024-2028	1,238
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Gross Projected Benefit Payments [Abstract]
2019	45
2020	45
2021	45
2022	44
2023	43
2024-2028	197
Expected Medicare Part D Subsidies [Abstract]
2019	2
2020	2
2021	2
2022	2
2023	2
2024-2028	13
Defined Benefit Plan, Net Projected Benefit Payments [Abstract]
2019	43
2020	43
2021	43
2022	42
2023	41
2024-2028	$ 184

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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.

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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 prescription drug subsidy receipts expected after fifth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in next fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in fifth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in fourth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in third fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in second fiscal year following latest fiscal year.

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- Definition

The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in the five fiscal years thereafter (the aggregate net amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

+ References

No definition available.

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in Year 5 after the balance sheet date.

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in Year 4 after the balance sheet date.

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in Year 1 after the balance sheet date.

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in Year 3 after the balance sheet date.

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The amount of the benefits expected to be paid, net of the prescription drug subsidy receipts expected to be received in Year 2 after the balance sheet date.

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