Employee Benefit and Retirement Plans - Narrative (Details) - Subsequent Event - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2020	Oct. 22, 2020
Defined Benefit Plan Disclosure [Line Items]
Percentage of benefit obligation allocated to retirees		45.00%
Forecast \| Minimum
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation settlement	$ 155
Reclassification adjustment from accumulated other comprehensive loss	(45)
Forecast \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation settlement	160
Reclassification adjustment from accumulated other comprehensive loss	$ (50)

Defined Benefit Plan, Percentage of Benefit Obligation Settled Allocated to Retirees

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+ References

No definition available.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

+ References

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- Definition

Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

+ References

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