Segment information - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting [Abstract]
Taxable-equivalent adjustment	$ 12	$ 13	$ 33	$ 38