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Comprehensive income (Tables) | 12 Months Ended
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Dec. 31, 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 before reclassifications: |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized holding gains, net | 31 |  |  | — |  |  | — |  |  | — |  |  | 31 |  |  | (8) |  |  | 23 |
Unrealized losses on cash flow hedges | — |  |  | (296) |  |  | — |  |  | — |  |  | (296) |  |  | 77 |  |  | (219) |
Current year benefit plans gains | — |  |  | — |  |  | 305 |  |  | — |  |  | 305 |  |  | (78) |  |  | 227 |
Other | — |  |  | — |  |  | — |  |  | (3) |  |  | (3) |  |  | 1 |  |  | (2) |
Total other comprehensive income (loss) before reclassifications | 31 |  |  | (296) |  |  | 305 |  |  | (3) |  |  | 37 |  |  | (8) |  |  | 29 |
Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: |  |  |  |  |  |  |  |  |  |  |  |  |
Net losses realized in net income | 15 |  |  | — |  |  | — |  |  | — |  |  | 15 |  |  | (4) |  |  | 11 |
Net yield adjustment from cash flow hedges currently in effect | — |  |  | 364 |  |  | — |  |  | — |  |  | 364 |  | (a) | (95) |  |  | 269 |
Amortization of prior service credit | — |  |  | — |  |  | (2) |  |  | — |  |  | (2) |  | (b) | 1 |  |  | (1) |
Amortization of actuarial gains | — |  |  | — |  |  | (5) |  |  | — |  |  | (5) |  | (b) | 1 |  |  | (4) |
Settlement gain | — |  |  | — |  |  | (12) |  |  | — |  |  | (12) |  | (b) | 3 |  |  | (9) |
Total other comprehensive income (loss) | 46 |  |  | 68 |  |  | 286 |  |  | (3) |  |  | 397 |  |  | (102) |  |  | 295 |
Balance — December 31, 2024 | $ | (205) |  |  | $ | (135) |  |  | $ | 131 |  |  | $ | (10) |  |  | $ | (219) |  |  | $ | 55 |  |  | $ | (164) |
Balance — January 1, 2023 | $ | (444) |  |  | $ | (337) |  |  | $ | (273) |  |  | $ | (12) |  |  | $ | (1,066) |  |  | $ | 276 |  |  | $ | (790) |
Other comprehensive income before reclassifications: |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized holding gains, net | 193 |  |  | — |  |  | — |  |  | — |  |  | 193 |  |  | (51) |  |  | 142 |
Unrealized losses on cash flow hedges | — |  |  | (116) |  |  | — |  |  | — |  |  | (116) |  |  | 30 |  |  | (86) |
Current year benefit plans gains | — |  |  | — |  |  | 125 |  |  | — |  |  | 125 |  |  | (33) |  |  | 92 |
Other | — |  |  | — |  |  | — |  |  | 5 |  |  | 5 |  |  | (1) |  |  | 4 |
Total other comprehensive income (loss) before reclassifications | 193 |  |  | (116) |  |  | 125 |  |  | 5 |  |  | 207 |  |  | (55) |  |  | 152 |
Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: |  |  |  |  |  |  |  |  |  |  |  |  |
Net yield adjustment from cash flow hedges currently in effect | — |  |  | 250 |  |  | — |  |  | — |  |  | 250 |  | (a) | (66) |  |  | 184 |
Amortization of prior service credit | — |  |  | — |  |  | (2) |  |  | — |  |  | (2) |  | (b) | 1 |  |  | (1) |
Amortization of actuarial gains | — |  |  | — |  |  | (5) |  |  | — |  |  | (5) |  | (b) | 1 |  |  | (4) |
Total other comprehensive income (loss) | 193 |  |  | 134 |  |  | 118 |  |  | 5 |  |  | 450 |  |  | (119) |  |  | 331 |
Balance — December 31, 2023 | $ | (251) |  |  | $ | (203) |  |  | $ | (155) |  |  | $ | (7) |  |  | $ | (616) |  |  | $ | 157 |  |  | $ | (459) |
(Dollars in millions) | Investment Securities |  | Cash Flow Hedges |  | Defined Benefit Plans |  | Other |  | Total Amount Before Tax |  | Income Tax |  | Net
Balance — January 1, 2022 | $ | 105 |  |  | $ | 88 |  |  | $ | (360) |  |  | $ | (4) |  |  | $ | (171) |  |  | $ | 44 |  |  | $ | (127) |
Other comprehensive income before reclassifications: |  |  |  |  |  |  |  |  |  |  |  |  |
Unrealized holding losses, net | (551) |  |  | — |  |  | — |  |  | — |  |  | (551) |  |  | 143 |  |  | (408) |
Unrealized losses on cash flow hedges | — |  |  | (461) |  |  | — |  |  | — |  |  | (461) |  |  | 119 |  |  | (342) |
Current year benefit plans gains | — |  |  | — |  |  | 71 |  |  | — |  |  | 71 |  |  | (18) |  |  | 53 |
Other | — |  |  | — |  |  | — |  |  | (8) |  |  | (8) |  |  | 2 |  |  | (6) |
Total other comprehensive income (loss) before reclassifications | (551) |  |  | (461) |  |  | 71 |  |  | (8) |  |  | (949) |  |  | 246 |  |  | (703) |
Amounts reclassified from accumulated other comprehensive income that (increase) decrease net income: |  |  |  |  |  |  |  |  |  |  |  |  |
Amortization of unrealized holding losses on held-to-maturity securities | 2 |  |  | — |  |  | — |  |  | — |  |  | 2 |  | (a) | (1) |  |  | 1 |
Net yield adjustment from cash flow hedges currently in effect | — |  |  | 36 |  |  | — |  |  | — |  |  | 36 |  | (a) | (9) |  |  | 27 |
Amortization of prior service credit | — |  |  | — |  |  | (2) |  |  | — |  |  | (2) |  | (b) | — |  |  | (2) |
Amortization of actuarial losses | — |  |  | — |  |  | 18 |  |  | — |  |  | 18 |  | (b) | (4) |  |  | 14 |
Total other comprehensive income (loss) | (549) |  |  | (425) |  |  | 87 |  |  | (8) |  |  | (895) |  |  | 232 |  |  | (663) |
Balance — December 31, 2022 | $ | (444) |  |  | $ | (337) |  |  | $ | (273) |  |  | $ | (12) |  |  | $ | (1,066) |  |  | $ | 276 |  |  | $ | (790) |
__________________________________________________________________________________ (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 at January 1, 2022 | $ | 78 |  |  | $ | 66 |  |  | $ | (267) |  |  | $ | (4) |  |  | $ | (127) |
Net gain (loss) during 2022 | (407) |  |  | (315) |  |  | 65 |  |  | (6) |  |  | (663) |
Balance at December 31, 2022 | (329) |  |  | (249) |  |  | (202) |  |  | (10) |  |  | (790) |
Net gain during 2023 | 142 |  |  | 98 |  |  | 87 |  |  | 4 |  |  | 331 |
Balance at December 31, 2023 | (187) |  |  | (151) |  |  | (115) |  |  | (6) |  |  | (459) |
Net gain (loss) during 2024 | 34 |  |  | 50 |  |  | 213 |  |  | (2) |  |  | 295 |
Balance at December 31, 2024 | $ | (153) |  |  | $ | (101) |  |  | $ | 98 |  |  | $ | (8) |  |  | $ | (164) |

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