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Derivative And Credit-Related Financial Instruments (Schedule Of Derivative Instruments) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 70,737 | $ 67,665
Fair Value of Gross Derivative Assets |  | 1,019 | 1,279
Fair Value of Gross Derivative Liabilities |  | 1,206 | 1,695
Derivative assets, Netting adjustment - Offsetting derivative liabilities |  | (311) | (644)
Derivative liabilities, Netting adjustment - Offsetting derivative assets |  | (311) | (644)
Derivative assets, Netting adjustment - Cash collateral received |  | (143) | (180)
Derivative liabilities, Netting adjustment - Cash collateral posted |  | (13) | (4)
Derivative Asset, Subject to Master Netting Arrangement, after Offset | [2] | 565 | 455
Derivative Liability, Subject to Master Netting Arrangement, after Offset | [2] | 882 | 1,047
Derivative assets, securities pledged as collateral |  | (501) | (70)
Derivative liabilities, securities pledged as collateral |  | (4) | (202)
Net derivative assets after deducting amounts not offset in the consolidated balance sheets |  | 64 | 385
Net derivative liabilities after deducting amounts not offset in the consolidated balance sheets |  | 878 | 845
Risk management purposes |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 31,710 | 30,142
Fair Value of Gross Derivative Assets |  | 1 | 1
Fair Value of Gross Derivative Liabilities |  | 11 | 53
Risk management purposes | Derivatives designated as hedging instruments | Swaps - fair value - receive fixed/pay floating | Interest rate swap |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 6,300 | 3,150
Fair Value of Gross Derivative Assets |  | 0 | 0
Fair Value of Gross Derivative Liabilities |  | 0 | 0
Risk management purposes | Derivatives designated as hedging instruments | Swaps - cash flow - receive fixed/pay floating rate | Interest rate swap |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 24,850 | 26,600
Fair Value of Gross Derivative Assets |  | 0 | 0
Fair Value of Gross Derivative Liabilities |  | 8 | 50
Risk management purposes | Derivatives used as economic hedges | Foreign exchange spot, forwards and swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 560 | 392
Fair Value of Gross Derivative Assets |  | 1 | 1
Fair Value of Gross Derivative Liabilities |  | 3 | 3
Customer-initiated and other activities |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 39,027 | 37,523
Fair Value of Gross Derivative Assets |  | 1,018 | 1,278
Fair Value of Gross Derivative Liabilities |  | 1,195 | 1,642
Customer-initiated and other activities | Interest rate contracts |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 22,470 | 20,298
Fair Value of Gross Derivative Assets |  | 225 | 206
Fair Value of Gross Derivative Liabilities |  | 427 | 594
Customer-initiated and other activities | Interest rate caps and floors written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 1,577 | 924
Fair Value of Gross Derivative Assets |  | 0 | 0
Fair Value of Gross Derivative Liabilities |  | 18 | 25
Customer-initiated and other activities | Interest rate caps and floors purchased |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 1,577 | 924
Fair Value of Gross Derivative Assets |  | 18 | 25
Fair Value of Gross Derivative Liabilities |  | 0 | 0
Customer-initiated and other activities | Interest rate swap |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 19,316 | 18,450
Fair Value of Gross Derivative Assets |  | 207 | 181
Fair Value of Gross Derivative Liabilities |  | 409 | 569
Customer-initiated and other activities | Energy contracts |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 13,806 | 14,521
Fair Value of Gross Derivative Assets |  | 758 | 1,020
Fair Value of Gross Derivative Liabilities |  | 736 | 1,006
Customer-initiated and other activities | Energy caps and floors written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 3,719 | 4,051
Fair Value of Gross Derivative Assets |  | 3 | 0
Fair Value of Gross Derivative Liabilities |  | 291 | 430
Customer-initiated and other activities | Energy caps and floors purchased |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 3,719 | 4,051
Fair Value of Gross Derivative Assets |  | 292 | 431
Fair Value of Gross Derivative Liabilities |  | 3 | 0
Customer-initiated and other activities | Energy swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 6,368 | 6,419
Fair Value of Gross Derivative Assets |  | 463 | 589
Fair Value of Gross Derivative Liabilities |  | 442 | 576
Customer-initiated and other activities | Foreign exchange spot, options and swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount |  | 2,751 | 2,704
Fair Value of Gross Derivative Assets |  | 35 | 52
Fair Value of Gross Derivative Liabilities |  | $ 32 | $ 42
[1] | Notional or contractual amounts, which represent the extent of involvement in the derivatives market, are used to determine the contractual cash flows required in accordance with the terms of the agreement. These amounts are typically not exchanged, significantly exceed amounts subject to credit or market risk and are not reflected on the Consolidated Balance Sheets. (b)December 31, 2023 included $2.0 billion of forward starting swaps that will become effective on their contractual start dates in 2024.
[2] | Net derivative assets are included in accrued income and other assets and net derivative liabilities are included in accrued expenses and other liabilities on the Consolidated Balance Sheets. Included in the fair value of net derivative assets and net derivative liabilities are credit valuation adjustments reflecting counterparty credit risk and credit risk of the Corporation. The fair value of net derivative assets included credit valuation adjustments for counterparty credit risk of $3 million and $2 million at December 31, 2023 and 2022, respectively.

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