Allowance for Credit Losses - Schedule of Allowance for Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	$ 1,605	$ 848	$ 922	$ 178
Initial PCD ACL		(12)
Initial PCD ACL	20		220	272
Day 2 provision for loans and leases	0	0	462	454
Provision for credit losses - loans and leases	169	36	240
(Benefit) for credit losses - loans and leases				(17)
Total provision for credit losses- loans and leases	169	36	702	437
charege-offs	(176)	(41)	(238)	(74)
Recoveries	19	19	31	37
Allowance for credit losses, ending balance	1,637	850	1,637	850
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	800	743	789	80
Initial PCD ACL		(12)
Initial PCD ACL	0		0	258
Day 2 provision for loans and leases	0	0	0	432
Provision for credit losses - loans and leases	172	33	230	10
Total provision for credit losses- loans and leases	172	33	230	442
charege-offs	(69)	(36)	(124)	(64)
Recoveries	12	12	20	24
Allowance for credit losses, ending balance	915	740	915	740
Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	143	105	133	98
Initial PCD ACL	0	0	0	14
Day 2 provision for loans and leases	0	0	0	22
Provision for credit losses - loans and leases	16	3	29
(Benefit) for credit losses - loans and leases				(27)
Total provision for credit losses- loans and leases	16	3	29	(5)
charege-offs	(6)	(5)	(13)	(10)
Recoveries	3	7	7	13
Allowance for credit losses, ending balance	156	110	156	110
SVB
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for credit losses, beginning balance	662	0	0	0
Initial PCD ACL	20	0	220	0
Day 2 provision for loans and leases	0	0	462	0
Provision for credit losses - loans and leases		0		0
(Benefit) for credit losses - loans and leases	(19)		(19)
Total provision for credit losses- loans and leases	(19)	0	443	0
charege-offs	(101)	0	(101)	0
Recoveries	4	0	4	0
Allowance for credit losses, ending balance	$ 566	$ 0	$ 566	$ 0