Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 4,010	$ 7,311
Other comprehensive income (loss), net-of-tax:
Net change in debt securities	4,795	2,309
Net change in debit valuation adjustments	1,346	(363)
Net change in derivatives	417	229
Employee benefit plan adjustments	43	28
Net change in foreign currency translation adjustments	(88)	(34)
Other comprehensive income (loss)	6,513	2,169
Comprehensive income	$ 10,523	$ 9,480

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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