Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 7,311	$ 6,918
Other comprehensive income (loss), net-of-tax:
Net change in debt and equity securities	2,309	(3,963)
Net change in debit valuation adjustments	(363)	273
Net change in derivatives	229	(275)
Employee benefit plan adjustments	28	30
Net change in foreign currency translation adjustments	(34)	(48)
Other comprehensive income (loss)	2,169	(3,983)
Comprehensive income	$ 9,480	$ 2,935

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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