SEGMENT INFORMATION - Schedule of Segment Assets (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Segment Reporting [Line Items]
Assets	$ 5,855	$ 5,354
Deferred income tax assets	124	270
Cash and cash equivalents	158	120
Corporate non segment
Segment Reporting [Line Items]
Deferred income tax assets	124	270
Cash and cash equivalents	158	120
Fair value of derivative instruments and other financial assets	43	83
A&T \| Segments
Segment Reporting [Line Items]
Assets	1,661	1,375
P&ARP \| Segments
Segment Reporting [Line Items]
Assets	2,706	2,405
AS&I \| Segments
Segment Reporting [Line Items]
Assets	700	711
H&C \| Segments
Segment Reporting [Line Items]
Assets	$ 463	$ 390

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