Commitments and contingencies - Schedule of Unusual or Infrequent Items, or Both (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Kennewick, Washington Warehouse Fire
Unusual or Infrequent Item, or Both [Line Items]
Less: Insurance reimbursement	$ (13)	$ 0	$ (13)	$ 0
Kennewick, Washington Warehouse Fire
Unusual or Infrequent Item, or Both [Line Items]
Clean-up costs and legal and administrative fees	4	0	5	1
Less: Insurance reimbursement	(16)	(13)	(20)	(38)
Net (gain) loss	$ (12)	$ (13)	$ (15)	$ (37)

Amount of insurance proceeds for an event or transaction that is unusual in nature or infrequent in occurrence, or both.

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