Fair Value Measurements - Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities) (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Cash and cash equivalents
Interest-bearing deposits at banks	$ 24,417	$ 28,069
Investment securities held to maturity	32,327	26,897
Loans and leases, net	133,716	131,939
Financial liabilities:
Short-term borrowings	105	316
Loan facility carrying amount	11,583	8,201
Level 1
Cash and cash equivalents
Cash and cash equivalents	2,107	1,668
Interest-bearing deposits at banks	0	0
Investment securities held to maturity	0	0
Loans and leases, net	0	0
Financial liabilities:
Time deposits	0	0
Short-term borrowings	0	0
Loan facility carrying amount	0	0
Level 2
Cash and cash equivalents
Cash and cash equivalents	109	63
Interest-bearing deposits at banks	24,417	28,069
Investment securities held to maturity	13,666	14,262
Loans and leases, net	7,581	7,240
Financial liabilities:
Time deposits	16,514	20,715
Short-term borrowings	2,605	5,316
Loan facility carrying amount	11,705	8,107
Level 3
Cash and cash equivalents
Cash and cash equivalents	0	0
Interest-bearing deposits at banks	0	0
Investment securities held to maturity	43	46
Loans and leases, net	124,505	121,898
Financial liabilities:
Time deposits	0	0
Short-term borrowings	0	0
Loan facility carrying amount	0	0
Carrying Amount
Cash and cash equivalents
Cash and cash equivalents	2,216	1,731
Interest-bearing deposits at banks	24,417	28,069
Investment securities held to maturity	14,503	15,330
Loans and leases, net	133,716	131,939
Financial liabilities:
Time deposits	16,512	20,759
Short-term borrowings	2,605	5,316
Loan facility carrying amount	11,583	8,201
Estimated Fair Value
Cash and cash equivalents
Cash and cash equivalents	2,216	1,731
Interest-bearing deposits at banks	24,417	28,069
Investment securities held to maturity	13,709	14,308
Loans and leases, net	132,086	129,138
Financial liabilities:
Time deposits	16,514	20,715
Short-term borrowings	2,605	5,316
Loan facility carrying amount	$ 11,705	$ 8,107

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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