Pension Plans and Other Postretirement Benefits - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer contributions	$ 657	$ 610	$ 581
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 4,337	4,349	$ 4,736
Pension Plan | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	7.00%
Pension Plan | Debt securities
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	75.00%
Pension Plan | Real assets
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	7.00%
Pension Plan | Private equity limited partnerships
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	5.00%
Pension Plan | Private credit limited partnerships
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	2.00%
Pension Plan | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Target investment allocations	4.00%
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 151	$ 147