Benefit Obligations - Schedule of Company Commitments to Fund Benefit Obligations (Details) $ in Millions	9 Months Ended
	Sep. 30, 2026 USD ($)
Cash contributions to defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Total contributions year-to-date	$ 23
Total expected contributions in current fiscal year	33
Benefit payments to nonqualified pension plans
Defined Benefit Plan Disclosure [Line Items]
Total contributions year-to-date	13
Total expected contributions in current fiscal year	17
Benefit payments to other postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Total contributions year-to-date	3
Total expected contributions in current fiscal year	$ 3