Fair Value Measurements (Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Financial Assets
Debt securities held to maturity	$ 701	$ 716
Debt securities available for sale	27,881	28,104
Other earning assets	1,478	1,417
Derivative Asset, Estimated Fair Value	2,231	2,105
Financial Liabilities
Fair value Discount On Loan Portfolio Amount	$ (4,200)	$ (3,800)
Fair value Discount On Loan Portfolio Rate	4.50%	4.00%
Capital Leases Carrying Amount Excluded	$ 1,700	$ 1,700
Derivative Liability, Estimated Fair Value	3,096	2,691
Carrying Amount [Member]
Financial Assets
Cash and cash equivalents	11,250	6,801
Debt securities held to maturity	743	754
Debt securities available for sale	27,881	28,104
Loans held for sale	417	400
Loans (excluding leases), net of unearned income and allowance for loan losses	93,557	95,141
Other earning assets	1,478	1,417
Derivative Asset, Estimated Fair Value	2,231	2,105
Financial Liabilities
Deposits with no stated maturity, Fair Value Disclosure	113,529	112,816
Time deposits. fair value disclosure	15,453	14,972
Short-term Borrowings	1,000
Long-term Borrowings	3,327	2,330
Loan commitments and letters of credit	145	156
Derivative Liability, Estimated Fair Value	3,096	2,691
Estimate of Fair Value [Member]
Financial Assets
Cash and cash equivalents	11,250	6,801
Debt securities held to maturity	701	716
Debt securities available for sale	27,881	28,104
Loans held for sale	417	400
Loans (excluding leases), net of unearned income and allowance for loan losses	89,366	91,352
Other earning assets	1,478	1,417
Derivative Asset, Estimated Fair Value	2,231	2,105
Financial Liabilities
Deposits with no stated maturity, Fair Value Disclosure	113,529	112,816
Time deposits. fair value disclosure	15,391	14,905
Short-term Borrowings	1,000
Long-term Borrowings	3,319	2,319
Loan commitments and letters of credit	145	156
Derivative Liability, Estimated Fair Value	3,096	2,691
Level 1 [Member]
Financial Assets
Cash and cash equivalents	11,250	6,801
Debt securities held to maturity	0	0
Debt securities available for sale	1,110	1,223
Loans held for sale	0	0
Loans (excluding leases), net of unearned income and allowance for loan losses	0	0
Other earning assets	747	813
Derivative Asset, Estimated Fair Value	0	0
Financial Liabilities
Deposits with no stated maturity, Fair Value Disclosure	0	0
Time deposits. fair value disclosure	0	0
Short-term Borrowings	0
Long-term Borrowings	0	0
Loan commitments and letters of credit	0	0
Derivative Liability, Estimated Fair Value	0	0
Level 2 [Member]
Financial Assets
Cash and cash equivalents	0	0
Debt securities held to maturity	701	716
Debt securities available for sale	26,768	26,880
Loans held for sale	414	397
Loans (excluding leases), net of unearned income and allowance for loan losses	0	0
Other earning assets	731	604
Derivative Asset, Estimated Fair Value	2,221	2,101
Financial Liabilities
Deposits with no stated maturity, Fair Value Disclosure	113,529	112,816
Time deposits. fair value disclosure	15,391	14,905
Short-term Borrowings	1,000
Long-term Borrowings	3,318	2,318
Loan commitments and letters of credit	0	0
Derivative Liability, Estimated Fair Value	3,096	2,690
Level 3 [Member]
Financial Assets
Cash and cash equivalents	0	0
Debt securities held to maturity	0	0
Debt securities available for sale	3	1
Loans held for sale	3	3
Loans (excluding leases), net of unearned income and allowance for loan losses	89,366	91,352
Other earning assets	0	0
Derivative Asset, Estimated Fair Value	10	4
Financial Liabilities
Deposits with no stated maturity, Fair Value Disclosure	0	0
Time deposits. fair value disclosure	0	0
Short-term Borrowings	0
Long-term Borrowings	1	1
Loan commitments and letters of credit	145	156
Derivative Liability, Estimated Fair Value	$ 0	$ 1

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Fair value discount on loan portfolio, amount

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Fair value discount on loan portfolio, rate

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Leases, carrying amount excluded

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Time deposits, Fair Value Disclosure

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion 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.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of interest earning assets classified as other.

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Fair value portion of other liabilities.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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