Retirement and Benefit Plans - Schedule of Estimated Future Benefit Payments (Details) $ in Millions	Mar. 31, 2026 USD ($)
Pension Plan \| Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Remainder of 2026	$ 178
2027	151
2028	147
2029	148
2030	147
2031 - 2035	684
Pension Plan \| Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Remainder of 2026	15
2027	15
2028	15
2029	15
2030	15
2031 - 2035	71
Postemployment Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Remainder of 2026	2
2027	2
2028	2
2029	2
2030	1
2031 - 2035	$ 5

Defined Benefit Plan, Estimated Future Benefit Payments, After Year Four For Next Five Years

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Amount of benefit for defined benefit plan expected to be paid in remainder of current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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