Pension And Other Retirement Plans Narrative (Details) - Scenario, Forecast $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Contributions by employer	$ 3
Other Post Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Contributions by employer	$ 1

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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-Name Accounting Standards Codification
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Name:	us-gaap_DefinedBenefitPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration