Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Assets pledged	$ 122,400	$ 166,600
Available-for-sale securities, amortized cost, net of allowance for credit losses	249,733	381,729
Loans	$ 60,628	$ 44,474
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	200,000,000	200,000,000
Preferred stock, shares issued (in shares)	3,483,750	3,006,250
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	9,000,000,000	9,000,000,000
Common stock, shares issued (in shares)	4,104,933,895	4,104,933,895
Treasury stock, at cost (in shares)	1,149,667,834	1,055,499,435
Trading assets
Assets
Assets pledged	$ 104,047	$ 130,645
Investment securities - AFS
Assets
Assets pledged	13,621	32,227
Other assets
Assets
Assets pledged	4,740	3,739
Recurring
Assets
Federal funds sold and securities purchased under resale agreements	273,158	238,015
Securities borrowed	72,833	52,983
Loans	60,628	44,474
Liabilities
Deposits	11,808	14,484
Federal funds purchased and securities loaned or sold under repurchase agreements	187,439	155,735
Short-term borrowings	20,033	16,893
Accounts payable and other liabilities	5,340	3,476
Beneficial interests issued by consolidated VIEs	99	41
Long-term debt	76,499	76,817
Recurring | Other assets
Assets
Other assets	$ 14,471	$ 13,827