SUPPLEMENTARY INFORMATION - Schedule of Sundry Income (Expense) - Net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Net gain on sales of assets	$ 0	$ 1	$ 5	$ 1
Non-operating pension credits (costs)	1	(2)	3	(2)
Interest income	4	0	11	2
Foreign exchange (losses) gains - net	(5)	1	(12)	(4)
Indirect legacy (costs) benefits - net	(39)	0	(84)	0
Miscellaneous income (expense) - net	0	(1)	6	0
Other income (expense) - net	$ (39)	$ (1)	$ (71)	$ (3)

Indirect Legacy Benefits (Costs)

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Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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Amount of income (expense) related to nonoperating activities, classified as other.

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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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