Variable Interest Entities and Securitization Activities - Transfers of Assets with Continuing Involvement (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Variable Interest Entity
Derivative assets	$ 32,624	$ 29,173
Derivative liabilities	35,402	27,258
SPE
Variable Interest Entity
Interests purchased in the secondary market	328	299
Derivative assets	201	216
Derivative liabilities	69	178
SPE \| Investment grade
Variable Interest Entity
Interests purchased in the secondary market	271	200
SPE \| Non-investment grade
Variable Interest Entity
Interests purchased in the secondary market	57	99
SPE \| RML
Variable Interest Entity
SPE assets (UPB)	12,726	14,376
Retained interest	45	21
Interests purchased in the secondary market	42	35
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| RML \| Investment grade
Variable Interest Entity
Retained interest	27	17
Interests purchased in the secondary market	7	7
SPE \| RML \| Non-investment grade
Variable Interest Entity
Retained interest	18	4
Interests purchased in the secondary market	35	28
SPE \| CML
Variable Interest Entity
SPE assets (UPB)	77,431	68,593
Retained interest	819	695
Interests purchased in the secondary market	266	162
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| CML \| Investment grade
Variable Interest Entity
Retained interest	620	483
Interests purchased in the secondary market	244	91
SPE \| CML \| Non-investment grade
Variable Interest Entity
Retained interest	199	212
Interests purchased in the secondary market	22	71
SPE \| U.S. Agency CMO
Variable Interest Entity
SPE assets (UPB)	14,841	16,594
Retained interest	1,463	1,573
Interests purchased in the secondary market	15	102
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| U.S. Agency CMO \| Investment grade
Variable Interest Entity
Retained interest	1,463	1,573
Interests purchased in the secondary market	15	102
SPE \| U.S. Agency CMO \| Non-investment grade
Variable Interest Entity
Retained interest	0	0
Interests purchased in the secondary market	0	0
SPE \| CLN and Other
Variable Interest Entity
SPE assets (UPB)	6,637	14,608
Retained interest	90	213
Interests purchased in the secondary market	5	0
Derivative assets	201	216
Derivative liabilities	69	178
SPE \| CLN and Other \| Investment grade
Variable Interest Entity
Retained interest	1	3
Interests purchased in the secondary market	5	0
SPE \| CLN and Other \| Non-investment grade
Variable Interest Entity
Retained interest	89	210
Interests purchased in the secondary market	$ 0	$ 0

Fair value of interests purchased in the secondary market

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- Definition

The carrying value of an interest continued to be held by the transferor in a securitized financial instrument.

+ References

No definition available.

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

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-Publisher FASB
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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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-Name Accounting Standards Codification
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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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