v3.25.1

Pensions and Other Benefits - Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 6	$ 7
Interest cost	53	53
Expected return on plan assets	(65)	(74)
Amortization of prior service cost (credit)	4	4
Amortization of actuarial net loss (gain)	17	11
Net periodic benefit cost (income), excluding below	15	1
Multiemployer plans	20	20
Net periodic benefit cost (income)	35	21
Other Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	1	1
Interest cost	15	15
Expected return on plan assets	(16)	(18)
Amortization of prior service cost (credit)	2	(7)
Amortization of actuarial net loss (gain)	(13)	(16)
Net periodic benefit cost (income), excluding below	(11)	(25)
Multiemployer plans	0	0
Net periodic benefit cost (income)	$ (11)	$ (25)

Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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- Definition

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount of defined benefit plan cost (credit), classified as other.

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No definition available.

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The amount of net periodic benefit cost recognized during the period excluding multiemployer plans, settlements and curtailments.

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No definition available.

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