Fair Value Measurements - Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities) (Detail) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Cash and cash equivalents
Interest-bearing deposits at banks	$ 24,792	$ 28,069
Investment securities	29,894	26,897
Loans and leases, net	132,798	131,939
Financial liabilities:
Short-term borrowings	264	316
Loan facility carrying amount	11,319	8,201
Level 1
Cash and cash equivalents
Cash and cash equivalents	1,607	1,668
Interest-bearing deposits at banks	0	0
Investment securities	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	171	63
Interest-bearing deposits at banks	24,792	28,069
Investment securities	13,467	14,262
Loans and leases, net	6,865	7,240
Financial liabilities:
Time deposits	17,463	20,715
Short-term borrowings	4,764	5,316
Loan facility carrying amount	11,282	8,107
Level 3
Cash and cash equivalents
Cash and cash equivalents	0	0
Interest-bearing deposits at banks	0	0
Investment securities	42	46
Loans and leases, net	123,001	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	1,778	1,731
Interest-bearing deposits at banks	24,792	28,069
Investment securities	14,793	15,330
Loans and leases, net	132,798	131,939
Financial liabilities:
Time deposits	17,513	20,759
Short-term borrowings	4,764	5,316
Loan facility carrying amount	11,319	8,201
Estimated Fair Value
Cash and cash equivalents
Cash and cash equivalents	1,778	1,731
Interest-bearing deposits at banks	24,792	28,069
Investment securities	13,509	14,308
Loans and leases, net	129,866	129,138
Financial liabilities:
Time deposits	17,463	20,715
Short-term borrowings	4,764	5,316
Loan facility carrying amount	$ 11,282	$ 8,107

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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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