Retirement Plans (Schedule Of Amounts Recognized In Statement Of Financial Position) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Amounts recognized - noncurrent assets	$ 203	$ 172
Amounts recognized - current liabilities	(29)	(28)
Amounts recognized - noncurrent liabilities	(493)	(438)
Net amounts recognized at end of year	(319)	(294)
OPEB [Member]
Defined Benefit Plan Disclosure [Line Items]
Amounts recognized - noncurrent assets
Amounts recognized - current liabilities	(20)	(22)
Amounts recognized - noncurrent liabilities	(185)	(276)
Net amounts recognized at end of year	$ (205)	$ (298)

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

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- Definition

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

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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.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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