Pension and Other Postretirement Benefits (Schedule of Amounts Recognized in Accumulated Other Comprehensive (Loss) Income) (Parenthetical) (Details) $ in Millions	Jun. 30, 2019 USD ($)
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated other comprehensive loss transferred from 21CF	$ 188
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated other comprehensive loss transferred from 21CF	$ 18

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.

No definition available.

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