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Acquisitions (Narrative) (Details) - USD ($) $ in Millions			12 Months Ended
Acquisitions (Narrative) (Details) - USD ($) $ in Millions	Feb. 01, 2022	Oct. 01, 2021	Dec. 31, 2023	Dec. 31, 2022
Business Acquisition [Line Items]
Measurement period adjustment			$ 5	$ 24
Housing and Infrastructure Products Segment
Business Acquisition [Line Items]
Measurement period adjustment			1	16
Performance and Essential Materials Segment
Business Acquisition [Line Items]
Measurement period adjustment				$ 8
Hexion
Business Acquisition [Line Items]
Business Combination, Consideration Transferred	$ 1,207
Hexion \| Minimum
Business Acquisition [Line Items]
Intangible assets useful life	11 years
Hexion \| Maximum
Business Acquisition [Line Items]
Intangible assets useful life	19 years
Hexion \| Performance and Essential Materials Segment
Business Acquisition [Line Items]
Measurement period adjustment			$ 4
Boral Target Companies
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 2,140