Business Segments - Assets by Segment (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total	$ 1,163,028	$ 992,968
Investment Banking [Member]
Segment Reporting Information [Line Items]
Total	116,242	92,009
Global Markets [Member]
Segment Reporting Information [Line Items]
Total	844,606	725,060
Asset Management [Member]
Segment Reporting Information [Line Items]
Total	95,751	92,102
Consumer & Wealth Management [Member]
Segment Reporting Information [Line Items]
Total	$ 106,429	$ 83,797

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details