Pension and Postretirement Benefit Plans - Narrative (Details) $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($)
Qualified and Non-qualified Pension Benefits
Schedule Of Defined Contribution Plans Disclosures
Company contributions	$ 78
Postretirement Benefits
Schedule Of Defined Contribution Plans Disclosures
Company contributions	$ 7

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

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