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, 2022	Jun. 30, 2021
Allowance For Credit Loss [Abstract]
Balance at beginning of year	$ 765	$ 712
Provision for credit losses	50	49
Charge-offs, net of recoveries	(12)	(22)
Balance at June 30	$ 803	$ 739