Financing Receivables - By Portfolio Segment (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2025 USD ($) class	Dec. 31, 2024 USD ($) class
Financing receivables
Amortized cost	$ 10,785	$ 12,639
Allowance for credit losses:
Allowance for credit losses, beginning balance	128
Allowance for credit losses, ending balance	$ 149	$ 128
Client Financing Receivables
Financing receivables
Number of classes of financing receivable | class	3	3
Amortized cost	$ 9,738	$ 10,418
Allowance for credit losses:
Allowance for credit losses, beginning balance	123	150
Write-offs	0	(3)
Recoveries	0	1
Additions/(releases)	19	(12)
Other	3	(14)
Allowance for credit losses, ending balance	144	123
Client Financing Receivables | Americas
Financing receivables
Amortized cost	5,376	5,861
Allowance for credit losses:
Allowance for credit losses, beginning balance	69	92
Write-offs	0	(2)
Recoveries	0	1
Additions/(releases)	7	(10)
Other	2	(11)
Allowance for credit losses, ending balance	78	69
Client Financing Receivables | Europe/Middle East/Africa
Financing receivables
Amortized cost	2,975	3,128
Allowance for credit losses:
Allowance for credit losses, beginning balance	45	48
Write-offs	0	(1)
Recoveries	0	0
Additions/(releases)	10	0
Other	1	(2)
Allowance for credit losses, ending balance	56	45
Client Financing Receivables | Asia Pacific
Financing receivables
Amortized cost	1,387	1,429
Allowance for credit losses:
Allowance for credit losses, beginning balance	9	11
Write-offs	0	0
Recoveries	0	0
Additions/(releases)	2	(2)
Other	0	0
Allowance for credit losses, ending balance	$ 11	$ 9