Pension and Other Employee Benefits (Adjustment to Accumulated Other Comprehensive Loss) (Details) $ in Millions	Dec. 31, 2019 USD ($)
Pension Plan [Member]
Defined Benefit Plans and PRB Plans [Line Items]
Amortization of net actuarial gain (loss)	$ (1,197)
Amortization of prior service (cost) credit	(4)
Total	(1,201)
PRB [Member]
Defined Benefit Plans and PRB Plans [Line Items]
Amortization of net actuarial gain (loss)	(13)
Amortization of prior service (cost) credit	0
Total	$ (13)

Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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 (s)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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