Variable Interest Entities and Securitization Activities - Transfers of Assets with Continuing Involvement (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Variable Interest Entity
Derivative assets	$ 32,764	$ 29,173
Derivative liabilities	32,020	27,258
SPE
Variable Interest Entity
Interests purchased in the secondary market	1,173	299
Derivative assets	85	216
Derivative liabilities	63	178
SPE \| Investment grade
Variable Interest Entity
Interests purchased in the secondary market	1,102	200
SPE \| Non-investment grade
Variable Interest Entity
Interests purchased in the secondary market	71	99
SPE \| RML
Variable Interest Entity
SPE assets (UPB)	14,334	14,376
Retained interest	37	21
Interests purchased in the secondary market	59	35
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| RML \| Investment grade
Variable Interest Entity
Retained interest	32	17
Interests purchased in the secondary market	22	7
SPE \| RML \| Non-investment grade
Variable Interest Entity
Retained interest	5	4
Interests purchased in the secondary market	37	28
SPE \| CML
Variable Interest Entity
SPE assets (UPB)	74,243	68,593
Retained interest	743	695
Interests purchased in the secondary market	252	162
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| CML \| Investment grade
Variable Interest Entity
Retained interest	557	483
Interests purchased in the secondary market	218	91
SPE \| CML \| Non-investment grade
Variable Interest Entity
Retained interest	186	212
Interests purchased in the secondary market	34	71
SPE \| U.S. Agency CMO
Variable Interest Entity
SPE assets (UPB)	18,449	16,594
Retained interest	455	1,573
Interests purchased in the secondary market	862	102
Derivative assets	0	0
Derivative liabilities	0	0
SPE \| U.S. Agency CMO \| Investment grade
Variable Interest Entity
Retained interest	455	1,573
Interests purchased in the secondary market	862	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)	4,157	14,608
Retained interest	89	213
Interests purchased in the secondary market	0	0
Derivative assets	85	216
Derivative liabilities	63	178
SPE \| CLN and Other \| Investment grade
Variable Interest Entity
Retained interest	2	3
Interests purchased in the secondary market	0	0
SPE \| CLN and Other \| Non-investment grade
Variable Interest Entity
Retained interest	87	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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- 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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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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