Variable Interest Entities - Securitization Activity (Details) - Securitization entities not consolidated - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Residential mortgage
Securitization activity [Abstract]
Principal securitized	$ 1,782	$ 1,330
All cash flows during the period:
Proceeds received from loan sales as financial instruments	1,822	1,338
Servicing fees collected	77	80
Cash flows received on interests	85	92
Commercial and other
Securitization activity [Abstract]
Principal securitized	764	2,991
All cash flows during the period:
Proceeds received from loan sales as financial instruments	782	2,991
Servicing fees collected	0	1
Cash flows received on interests	$ 51	$ 47

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.

+ Details

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=109247956&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=109247956&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=109247956&loc=d3e107207-111719

+ Details

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