Fair Value Option - Net Revenues from Borrowings under the Fair Value Option (Details) - Borrowings - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Option Quantitative Disclosures
Earnings impact	$ (5,476)	$ (7,307)	$ 2,358
Trading revenues
Fair Value Option Quantitative Disclosures
Earnings impact	(5,135)	(6,932)	2,679
Interest expense
Fair Value Option Quantitative Disclosures
Earnings impact	$ 341	$ 375	$ 321

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration