Pension and Other Employee Benefits (Schedule of Reconciliation of Amounts on our Balance Sheets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Pension Plan [Member]
Defined Benefit Plans and PRB Plans [Line Items]
Prior service (cost) credit	$ (23)	$ (27)
Net actuarial loss	(11,389)	(10,590)
Accumulated other comprehensive loss	(11,412)	(10,617)
Accumulated contributions in excess of (below) net periodic expense	3,739	4,482
Net amount recognized on our balance sheets	(7,673)	(6,135)
PRB [Member]
Defined Benefit Plans and PRB Plans [Line Items]
Prior service (cost) credit	0	0
Net actuarial loss	(148)	(121)
Accumulated other comprehensive loss	(148)	(121)
Accumulated contributions in excess of (below) net periodic expense	(239)	(251)
Net amount recognized on our balance sheets	$ (387)	$ (372)

The amount of contributions in excess of periodic benefit costs recorded.

No definition available.

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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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- Definition

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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