Securitizations and Variable Interest Entities, Transactions with Consolidated VIEs (Details) - USD ($) $ in Millions	Mar. 31, 2022		Dec. 31, 2021		Mar. 31, 2021
Variable Interest Entity [Line Items]
Assets	$ 1,939,709	[1]	$ 1,948,068	[1]	$ 1,957,264
Loans	911,807		895,394		$ 861,572
Long-term debt	(153,337)		(160,689)
Carrying value [Member]
Variable Interest Entity [Line Items]
Long-term debt	(153,243)		(160,660)
VIEs that we consolidate [Member]
Variable Interest Entity [Line Items]
Assets	7,497		7,529
VIEs that we consolidate [Member] | Commercial and industrial loans and leases [Member]
Variable Interest Entity [Line Items]
Assets	7,026		7,013
VIEs that we consolidate [Member] | Other [Member]
Variable Interest Entity [Line Items]
Assets	471		516
VIEs that we consolidate [Member] | Carrying value [Member]
Variable Interest Entity [Line Items]
Assets	5,170		4,781
Loans	4,870		4,476
Debt securities	71		71
All other assets	229		234
Long-term debt	(133)		(149)
All other liabilities	(265)		(259)
VIEs that we consolidate [Member] | Carrying value [Member] | Commercial and industrial loans and leases [Member]
Variable Interest Entity [Line Items]
Loans	4,534		4,099
Debt securities	0		0
All other assets	226		231
Long-term debt	0		0
All other liabilities	(194)		(188)
VIEs that we consolidate [Member] | Carrying value [Member] | Other [Member]
Variable Interest Entity [Line Items]
Loans	336		377
Debt securities	71		71
All other assets	3		3
Long-term debt	(133)		(149)
All other liabilities	$ (71)		$ (71)

[1] Our consolidated assets at March 31, 2022 and December 31, 2021, included the following assets of certain variable interest entities (VIEs) that can only be used to settle the liabilities of those VIEs: Debt securities, $71 million and $71 million; Loans, $4.9 billion and $4.5 billion; All other assets, $229 million and $234 million; and Total assets, $5.2 billion and $4.8 billion, respectively.