Loans and finance receivables - Schedule of reconciliation of allowance for credit losses on loans and finance receivables (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Allowance for Credit Loss [Abstract]
Balance at the beginning of the year	$ 1,347	$ 1,134
Provision for credit losses	124	253
Charge-offs, net of recoveries	(96)	(80)
Balance at June 30	$ 1,375	$ 1,307

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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