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Goodwill - Changes in Goodwill (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2025 USD ($)
Goodwill [Line Items]
Balance at January 1, 2025	$ 3,767
Acquisitions	207
Adjustments to purchase price allocations	7
Goodwill reclassified to assets held for sale	(374)
Balance at June 30, 2025	3,607
East Group
Goodwill [Line Items]
Balance at January 1, 2025	1,031
Adjustments to purchase price allocations	(1)
Balance at June 30, 2025	1,030
West Group
Goodwill [Line Items]
Balance at January 1, 2025	2,736
Adjustments to purchase price allocations	8
Goodwill reclassified to assets held for sale	(374)
Balance at June 30, 2025	2,370
Specialties
Goodwill [Line Items]
Acquisitions	207
Balance at June 30, 2025	$ 207

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