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Derivative And Credit-Related Financial Instruments (Schedule Of Derivative Instruments) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | $ 67,665 | $ 41,638
Fair Value of Gross Derivative Assets |  | 1,279 | 928
Fair Value of Gross Derivative Liabilities |  | 1,695 | 747
Derivative assets, Netting adjustment - Offsetting derivative liabilities |  | (644) | (187)
Derivative liabilities, Netting adjustment - Offsetting derivative assets |  | (644) | (187)
Derivative assets, Netting adjustment - Cash collateral received |  | (180) | (15)
Derivative liabilities, Netting adjustment - Cash collateral posted |  | (4) | (452)
Net derivative assets included in consolidated balance sheets | [2] | 455 | 726
Net derivative liabilities included in the consolidated balance sheet | [2] | 1,047 | 108
Derivative assets, securities pledged as collateral |  | (70) | 0
Derivative liabilities, securities pledged as collateral |  | (202) | (52)
Net derivative assets after deducting amounts not offset in the consolidated balance sheets |  | 385 | 726
Net derivative liabilities after deducting amounts not offset in the consolidated balance sheets |  | 845 | 56
Risk Management Purposes |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 30,142 | 11,152
Fair Value of Gross Derivative Assets |  | 1 | 0
Fair Value of Gross Derivative Liabilities |  | 53 | 2
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 | [1] | 3,150 | 2,650
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 | [1],[3] | 26,600 | 8,050
Fair Value of Gross Derivative Assets | [3] | 0 | 0
Fair Value of Gross Derivative Liabilities | [3] | 50 | 0
Risk Management Purposes | Derivatives used as economic hedges | Foreign exchange spot, forwards and swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 392 | 452
Fair Value of Gross Derivative Assets |  | 1 | 0
Fair Value of Gross Derivative Liabilities |  | 3 | 2
Customer-initiated and other activities |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 37,523 | 30,486
Fair Value of Gross Derivative Assets |  | 1,278 | 928
Fair Value of Gross Derivative Liabilities |  | 1,642 | 745
Customer-initiated and other activities | Interest rate caps and floors written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 924 | 809
Fair Value of Gross Derivative Assets |  | 0 | 0
Fair Value of Gross Derivative Liabilities |  | 25 | 3
Customer-initiated and other activities | Interest rate caps and floors purchased |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 924 | 809
Fair Value of Gross Derivative Assets |  | 25 | 3
Fair Value of Gross Derivative Liabilities |  | 0 | 0
Customer-initiated and other activities | Interest rate swap |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 18,450 | 19,382
Fair Value of Gross Derivative Assets |  | 181 | 236
Fair Value of Gross Derivative Liabilities |  | 569 | 66
Customer-initiated and other activities | Interest rate contracts |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 20,298 | 21,000
Fair Value of Gross Derivative Assets |  | 206 | 239
Fair Value of Gross Derivative Liabilities |  | 594 | 69
Customer-initiated and other activities | Energy caps and floors written |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 4,051 | 1,779
Fair Value of Gross Derivative Assets |  | 0 | 0
Fair Value of Gross Derivative Liabilities |  | 430 | 203
Customer-initiated and other activities | Energy caps and floors purchased |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 4,051 | 1,779
Fair Value of Gross Derivative Assets |  | 431 | 204
Fair Value of Gross Derivative Liabilities |  | 0 | 0
Customer-initiated and other activities | Energy swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 6,419 | 4,212
Fair Value of Gross Derivative Assets |  | 589 | 466
Fair Value of Gross Derivative Liabilities |  | 576 | 459
Customer-initiated and other activities | Energy contracts |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 14,521 | 7,770
Fair Value of Gross Derivative Assets |  | 1,020 | 670
Fair Value of Gross Derivative Liabilities |  | 1,006 | 662
Customer-initiated and other activities | Foreign exchange spot, options and swaps |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Notional Amount | [1] | 2,704 | 1,716
Fair Value of Gross Derivative Assets |  | 52 | 19
Fair Value of Gross Derivative Liabilities |  | $ 42 | $ 14
[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.
[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 $2 million and $9 million at December 31, 2022 and 2021, respectively.
[3] | December 31, 2022 included $4.6 billion of forward starting swaps that will become effective on their contractual start dates in 2023 and 2024.

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