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Comprehensive income (Tables) | 9 Months Ended
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Sep. 30, 2024
Equity [Abstract] |
Components of Other Comprehensive Income (Loss) and Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) to Net Income | The following tables display the components of other comprehensive income (loss) and amounts reclassified from accumulated other comprehensive income (loss) to net income:
(Dollars in millions) | Investment Securities |  | Cash Flow Hedges |  | Defined Benefit Plans |  | Other |  | Total Amount Before Tax |  | Income Tax |  | Net
Balance — January 1, 2024 | $ | (251) |  |  | $ | (203) |  |  | $ | (155) |  |  | $ | (7) |  |  | $ | (616) |  |  | $ | 157 |  |  | $ | (459) |
Other comprehensive income (loss) before reclassifications: |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized holding gains, net | 307 |  |  | — |  |  | — |  |  | — |  |  | 307 |  |  | (78) |  |  | 229 |
Unrealized losses on cash flow hedges | — |  |  | (26) |  |  | — |  |  | — |  |  | (26) |  |  | 7 |  |  | (19) |
Other | — |  |  | — |  |  | — |  |  | 3 |  |  | 3 |  |  | (1) |  |  | 2 |
Total other comprehensive income (loss) before reclassifications | 307 |  |  | (26) |  |  | — |  |  | 3 |  |  | 284 |  |  | (72) |  |  | 212 |
Amounts reclassified from accumulated other comprehensive income (loss) that (increase) decrease net income: |  |  |  |  |  |  |  |  |  |  |  |  |
Net losses realized in net income | 13 |  |  | — |  |  | — |  |  | — |  |  | 13 |  |  | (4) |  |  | 9 |
Net yield adjustment from cash flow hedges currently in effect | — |  |  | 288 |  |  | — |  |  | — |  |  | 288 |  | (a) | (73) |  |  | 215 |
Amortization of prior service credit | — |  |  | — |  |  | (2) |  |  | — |  |  | (2) |  | (b) | — |  |  | (2) |
Amortization of actuarial gains | — |  |  | — |  |  | (3) |  |  | — |  |  | (3) |  | (b) | 1 |  |  | (2) |
Total other comprehensive income (loss) | 320 |  |  | 262 |  |  | (5) |  |  | 3 |  |  | 580 |  |  | (148) |  |  | 432 |
Balance — September 30, 2024 | $ | 69 |  |  | $ | 59 |  |  | $ | (160) |  |  | $ | (4) |  |  | $ | (36) |  |  | $ | 9 |  |  | $ | (27) |
Balance — January 1, 2023 | $ | (444) |  |  | $ | (336) |  |  | $ | (273) |  |  | $ | (13) |  |  | $ | (1,066) |  |  | $ | 276 |  |  | $ | (790) |
Other comprehensive income (loss) before reclassifications: |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized holding losses, net | (2) |  |  | — |  |  | — |  |  | — |  |  | (2) |  |  | 1 |  |  | (1) |
Unrealized losses on cash flow hedges | — |  |  | (366) |  |  | — |  |  | — |  |  | (366) |  |  | 91 |  |  | (275) |
Total other comprehensive income (loss) before reclassifications | (2) |  |  | (366) |  |  | — |  |  | — |  |  | (368) |  |  | 92 |  |  | (276) |
Amounts reclassified from accumulated other comprehensive income (loss) that (increase) decrease net income: |  |  |  |  |  |  |  |  |  |  |  |  |
Net yield adjustment from cash flow hedges currently in effect | — |  |  | 173 |  |  | — |  |  | — |  |  | 173 |  | (a) | (44) |  |  | 129 |
Amortization of prior service credit | — |  |  | — |  |  | (1) |  |  | — |  |  | (1) |  | (b) | — |  |  | (1) |
Amortization of actuarial gains | — |  |  | — |  |  | (4) |  |  | — |  |  | (4) |  | (b) | — |  |  | (4) |
Total other comprehensive income (loss) | (2) |  |  | (193) |  |  | (5) |  |  | — |  |  | (200) |  |  | 48 |  |  | (152) |
Balance — September 30, 2023 | $ | (446) |  |  | $ | (529) |  |  | $ | (278) |  |  | $ | (13) |  |  | $ | (1,266) |  |  | $ | 324 |  |  | $ | (942) |
_______________________________________________________________ (a)Included in "interest income" in the Consolidated Statement of Income. (b)Included in "other costs of operations" in the Consolidated Statement of Income.
Accumulated Other Comprehensive Income (Loss), Net | Accumulated other comprehensive income (loss), net consisted of the following:
(Dollars in millions) | Investment Securities |  | Cash Flow Hedges |  | Defined Benefit Plans |  | Other |  | Total
Balance — December 31, 2023 | $ | (187) |  |  | $ | (151) |  |  | $ | (115) |  |  | $ | (6) |  |  | $ | (459) |
Net gain (loss) during period | 238 |  |  | 196 |  |  | (4) |  |  | 2 |  |  | 432 |
Balance — September 30, 2024 | $ | 51 |  |  | $ | 45 |  |  | $ | (119) |  |  | $ | (4) |  |  | $ | (27) |

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