Fair Value Measurements (Schedule Of Carrying Amounts And Estimated Fair Values Of Financial Instruments) (Details) - USD ($) |
Dec. 31, 2021 |
Dec. 31, 2020 |
||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Financial Assets | ||||||||||||||||||||||||
| Debt securities held to maturity | $ 950,000,000 | $ 1,215,000,000 | ||||||||||||||||||||||
| Debt securities available for sale | 28,481,000,000 | 27,154,000,000 | ||||||||||||||||||||||
| Other earning assets | 1,187,000,000 | 1,217,000,000 | ||||||||||||||||||||||
| Derivative Assets | [1],[2] | 412,000,000 | 921,000,000 | |||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | [1],[2] | 80,000,000 | 53,000,000 | |||||||||||||||||||||
| Fair value Discount On Loan Portfolio Amount | $ 220,000,000 | $ 1,200,000,000 | ||||||||||||||||||||||
| Fair value Discount On Loan Portfolio Rate | 0.30% | 1.40% | ||||||||||||||||||||||
| Capital Leases Carrying Amount Excluded | $ 1,400,000,000 | $ 1,500,000,000 | ||||||||||||||||||||||
| Operating Leases Carrying Amount Excluded | 83,000,000 | 200,000,000 | ||||||||||||||||||||||
| Estimate of Fair Value [Member] | ||||||||||||||||||||||||
| Financial Assets | ||||||||||||||||||||||||
| Cash and cash equivalents | 29,411,000,000 | [3] | 17,956,000,000 | [4] | ||||||||||||||||||||
| Debt securities held to maturity | 950,000,000 | [3] | 1,215,000,000 | [4] | ||||||||||||||||||||
| Debt securities available for sale | 28,481,000,000 | [3] | 27,154,000,000 | [4] | ||||||||||||||||||||
| Loans held for sale | 1,003,000,000 | [3] | 1,905,000,000 | [4] | ||||||||||||||||||||
| Loans (excluding leases), net of unearned income and allowance for loan losses | 85,086,000,000 | [3],[5],[6] | 82,773,000,000 | [4],[7],[8] | ||||||||||||||||||||
| Other earning assets | 1,104,000,000 | [3],[9] | 1,017,000,000 | [4],[10] | ||||||||||||||||||||
| Derivative Assets | 1,111,000,000 | [3] | 3,349,000,000 | [4] | ||||||||||||||||||||
| Other Assets, Fair Value Disclosure | 0 | 74,000,000 | ||||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | 1,012,000,000 | [3] | 1,598,000,000 | [4] | ||||||||||||||||||||
| Deposits | 139,101,000,000 | [3] | 122,511,000,000 | [4] | ||||||||||||||||||||
| Long-term Borrowings | 2,847,000,000 | [3] | 4,063,000,000 | [4] | ||||||||||||||||||||
| Loan commitments and letters of credit | 123,000,000 | [3] | 151,000,000 | [4] | ||||||||||||||||||||
| Carrying Amount [Member] | ||||||||||||||||||||||||
| Financial Assets | ||||||||||||||||||||||||
| Cash and cash equivalents | 29,411,000,000 | 17,956,000,000 | ||||||||||||||||||||||
| Debt securities held to maturity | 899,000,000 | 1,122,000,000 | ||||||||||||||||||||||
| Debt securities available for sale | 28,481,000,000 | 27,154,000,000 | ||||||||||||||||||||||
| Loans held for sale | 1,003,000,000 | 1,905,000,000 | ||||||||||||||||||||||
| Loans (excluding leases), net of unearned income and allowance for loan losses | 84,866,000,000 | [5],[6] | 81,597,000,000 | [7],[8] | ||||||||||||||||||||
| Other earning assets | 1,104,000,000 | [9] | 1,017,000,000 | [10] | ||||||||||||||||||||
| Derivative Assets | 1,111,000,000 | 3,349,000,000 | ||||||||||||||||||||||
| Other Assets, Fair Value Disclosure | 74,000,000 | |||||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | 1,012,000,000 | 1,598,000,000 | ||||||||||||||||||||||
| Deposits | 139,072,000,000 | 122,479,000,000 | ||||||||||||||||||||||
| Long-term Borrowings | 2,407,000,000 | 3,569,000,000 | ||||||||||||||||||||||
| Loan commitments and letters of credit | 123,000,000 | 151,000,000 | ||||||||||||||||||||||
| Level 1 [Member] | ||||||||||||||||||||||||
| Financial Assets | ||||||||||||||||||||||||
| Cash and cash equivalents | 29,411,000,000 | 17,956,000,000 | ||||||||||||||||||||||
| Debt securities held to maturity | 0 | 0 | ||||||||||||||||||||||
| Debt securities available for sale | 1,132,000,000 | 183,000,000 | ||||||||||||||||||||||
| Loans held for sale | 0 | 0 | ||||||||||||||||||||||
| Loans (excluding leases), net of unearned income and allowance for loan losses | 0 | [5] | 0 | [7] | ||||||||||||||||||||
| Other earning assets | 464,000,000 | [9] | 388,000,000 | [10] | ||||||||||||||||||||
| Derivative Assets | 0 | 2,000,000 | ||||||||||||||||||||||
| Other Assets, Fair Value Disclosure | 0 | 0 | ||||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | 0 | 2,000,000 | ||||||||||||||||||||||
| Deposits | 0 | 0 | ||||||||||||||||||||||
| Long-term Borrowings | 0 | 0 | ||||||||||||||||||||||
| Loan commitments and letters of credit | 0 | 0 | ||||||||||||||||||||||
| Level 2 [Member] | ||||||||||||||||||||||||
| Financial Assets | ||||||||||||||||||||||||
| Cash and cash equivalents | 0 | 0 | ||||||||||||||||||||||
| Debt securities held to maturity | 950,000,000 | 1,215,000,000 | ||||||||||||||||||||||
| Debt securities available for sale | 27,347,000,000 | 26,966,000,000 | ||||||||||||||||||||||
| Loans held for sale | 899,000,000 | 1,901,000,000 | ||||||||||||||||||||||
| Loans (excluding leases), net of unearned income and allowance for loan losses | 0 | [5] | 0 | [7] | ||||||||||||||||||||
| Other earning assets | 640,000,000 | [9] | 629,000,000 | [10] | ||||||||||||||||||||
| Derivative Assets | 1,098,000,000 | 3,303,000,000 | ||||||||||||||||||||||
| Other Assets, Fair Value Disclosure | 0 | 74,000,000 | ||||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | 1,009,000,000 | 1,590,000,000 | ||||||||||||||||||||||
| Deposits | 139,101,000,000 | 122,511,000,000 | ||||||||||||||||||||||
| Long-term Borrowings | 2,845,000,000 | 3,592,000,000 | ||||||||||||||||||||||
| Loan commitments and letters of credit | 0 | 0 | ||||||||||||||||||||||
| Level 3 [Member] | ||||||||||||||||||||||||
| Financial Assets | ||||||||||||||||||||||||
| Cash and cash equivalents | 0 | 0 | ||||||||||||||||||||||
| Debt securities held to maturity | 0 | 0 | ||||||||||||||||||||||
| Debt securities available for sale | 2,000,000 | 5,000,000 | ||||||||||||||||||||||
| Loans held for sale | 104,000,000 | 4,000,000 | ||||||||||||||||||||||
| Loans (excluding leases), net of unearned income and allowance for loan losses | 85,086,000,000 | [5] | 82,773,000,000 | [7] | ||||||||||||||||||||
| Other earning assets | 0 | [9] | 0 | [10] | ||||||||||||||||||||
| Derivative Assets | 13,000,000 | 44,000,000 | ||||||||||||||||||||||
| Other Assets, Fair Value Disclosure | 0 | 0 | ||||||||||||||||||||||
| Financial Liabilities | ||||||||||||||||||||||||
| Derivative Liabilities | 3,000,000 | 6,000,000 | ||||||||||||||||||||||
| Deposits | 0 | 0 | ||||||||||||||||||||||
| Long-term Borrowings | 2,000,000 | 471,000,000 | ||||||||||||||||||||||
| Loan commitments and letters of credit | $ 123,000,000 | $ 151,000,000 | ||||||||||||||||||||||
| ||||||||||||||||||||||||