Variable Interest Entities - Securitization Activity (Details) - Nonconsolidated entities - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Residential mortgage
Securitization activity [Abstract]
Principal securitized	$ 4,115	$ 534	$ 8,192	$ 3,598
All cash flows during the period:
Proceeds received from loan sales as financial instruments	4,218	554	8,452	3,690
Servicing fees collected	41	49	82	111
Cash flows received on interests	173	214	356	331
Commercial and other
Securitization activity [Abstract]
Principal securitized	2,876	861	4,788	4,049
All cash flows during the period:
Proceeds received from loan sales as financial instruments	2,909	912	4,879	4,185
Servicing fees collected	0	0	0	0
Cash flows received on interests	$ 71	$ 31	$ 123	$ 60

The principal amount of financial assets transferred during the period in securitizations accounted for as sales.

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- Definition

Securitization activity.

+ References

No definition available.

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- References

No definition available.

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- Definition

Cash Flows between a transferor and a transferee attributable to newly transferred assets related to either a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719

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- Definition

Cash flows between transferor and a transferee attributable to the transferor's interests related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor will have continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(5)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719

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- Definition

Cash Flows between a transferee and a transferor attributable to servicing fees related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in the transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(4)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107207-111719

+ Details

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