| Schedule of changes in accumulated other comprehensive income (loss) |
| | | | | | | | | | | | | | | Income | | | | | | | | | Tax | | | | | | Pre-tax | | Benefit | | Net of | (dollars in thousands) | | Amount | | (Expense) | | Tax | Accumulated other comprehensive loss at March 31, 2026 | | $ | (508,386) | | $ | 135,639 | | $ | (372,747) | Three months ended June 30, 2026 | | | | | | | | | | Investment securities: | | | | | | | | | | Unrealized net gains arising during the period | | | 9,650 | | | (2,575) | | | 7,075 | Reclassification of net losses to net income: | | | | | | | | | | Amortization of unrealized holding losses on held-to-maturity securities | | | 9,704 | | | (2,588) | | | 7,116 | Net change in investment securities | | | 19,354 | | | (5,163) | | | 14,191 | Cash flow derivative hedges: | | | | | | | | | | Unrealized net losses arising during the period | | | (30) | | | 8 | | | (22) | Amounts excluded from the assessment of hedge effectiveness | | | (1,671) | | | 456 | | | (1,215) | Net change in cash flow derivative hedges | | | (1,701) | | | 464 | | | (1,237) | Other comprehensive income | | | 17,653 | | | (4,699) | | | 12,954 | Accumulated other comprehensive loss at June 30, 2026 | | $ | (490,733) | | $ | 130,940 | | $ | (359,793) |
| | | | | | | | | | | | | | | Income | | | | | | | | | Tax | | | | | | Pre-tax | | Benefit | | Net of | (dollars in thousands) | | Amount | | (Expense) | | Tax | Accumulated other comprehensive loss at December 31, 2025 | | $ | (502,104) | | $ | 133,964 | | $ | (368,140) | Six months ended June 30, 2026 | | | | | | | | | | Investment securities: | | | | | | | | | | Unrealized net losses arising during the period | | | (10,655) | | | 2,842 | | | (7,813) | Reclassification of net losses to net income: | | | | | | | | | | Amortization of unrealized holding losses on held-to-maturity securities | | | 23,618 | | | (6,300) | | | 17,318 | Net change in investment securities | | | 12,963 | | | (3,458) | | | 9,505 | Cash flow derivative hedges: | | | | | | | | | | Unrealized net losses arising during the period | | | (75) | | | 20 | | | (55) | Amounts excluded from the assessment of hedge effectiveness | | | (1,517) | | | 414 | | | (1,103) | Net change in cash flow derivative hedges | | | (1,592) | | | 434 | | | (1,158) | Other comprehensive income | | | 11,371 | | | (3,024) | | | 8,347 | Accumulated other comprehensive loss at June 30, 2026 | | $ | (490,733) | | $ | 130,940 | | $ | (359,793) |
| | | | | | | | | | | | | | | Income | | | | | | | | | Tax | | | | | | Pre-tax | | Benefit | | Net of | (dollars in thousands) | | Amount | | (Expense) | | Tax | Accumulated other comprehensive loss at March 31, 2025 | | $ | (591,574) | | $ | 157,805 | | $ | (433,769) | Three months ended June 30, 2025 | | | | | | | | | | Investment securities: | | | | | | | | | | Unrealized net gains arising during the period | | | 26,354 | | | (7,030) | | | 19,324 | Reclassification of net losses to net income: | | | | | | | | | | Amortization of unrealized holding losses on held-to-maturity securities | | | 9,982 | | | (2,663) | | | 7,319 | Net change in investment securities | | | 36,336 | | | (9,693) | | | 26,643 | Cash flow derivative hedges: | | | | | | | | | | Unrealized net gains arising during the period | | | 113 | | | (29) | | | 84 | Amounts excluded from the assessment of hedge effectiveness | | | 47 | | | (13) | | | 34 | Net change in cash flow derivative hedges | | | 160 | | | (42) | | | 118 | Other comprehensive income | | | 36,496 | | | (9,735) | | | 26,761 | Accumulated other comprehensive loss at June 30, 2025 | | $ | (555,078) | | $ | 148,070 | | $ | (407,008) |
| | | | | | | | | | | | | | | Income | | | | | | | | | Tax | | | | | | Pre-tax | | Benefit | | Net of | (dollars in thousands) | | Amount | | (Expense) | | Tax | Accumulated other comprehensive loss at December 31, 2024 | | $ | (632,793) | | $ | 168,799 | | $ | (463,994) | Six months ended June 30, 2025 | | | | | | | | | | Investment securities: | | | | | | | | | | Unrealized net gains arising during the period | | | 57,717 | | | (15,395) | | | 42,322 | Reclassification of net losses to net income: | | | | | | | | | | Amortization of unrealized holding losses on held-to-maturity securities | | | 19,639 | | | (5,239) | | | 14,400 | Reclassification of net gains to net income: | | | | | | | | | | Investment securities gains, net | | | (37) | | | 10 | | | (27) | Net change in investment securities | | | 77,319 | | | (20,624) | | | 56,695 | Cash flow derivative hedges: | | | | | | | | | | Unrealized net gains arising during the period | | | 349 | | | (92) | | | 257 | Amounts excluded from the assessment of hedge effectiveness | | | 47 | | | (13) | | | 34 | Net change in cash flow derivative hedges | | | 396 | | | (105) | | | 291 | Other comprehensive income | | | 77,715 | | | (20,729) | | | 56,986 | Accumulated other comprehensive loss at June 30, 2025 | | $ | (555,078) | | $ | 148,070 | | $ | (407,008) |
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| Summary of changes in accumulated other comprehensive income (loss), net of tax |
| | | | | | | | | | | | | | | | | | Pensions | | | | | | | | Accumulated | | | and | | Available-for-Sale | | Held-to-Maturity | | Cash Flow | | Other | | | Other | | Investment | | Investment | | Derivative | | Comprehensive | (dollars in thousands) | | Benefits | | Securities | | Securities | | Hedges | | Loss | Three Months Ended June 30, 2026 | | | | | | | | | | | | | | | | Balance at beginning of period | | $ | (4,290) | | $ | (139,895) | | $ | (228,098) | | $ | (464) | | $ | (372,747) | Other comprehensive income (loss) | | | — | | | 7,075 | | | 7,116 | | | (1,237) | | | 12,954 | Balance at end of period | | $ | (4,290) | | $ | (132,820) | | $ | (220,982) | | $ | (1,701) | | $ | (359,793) | | | | | | | | | | | | | | | | | Six Months Ended June 30, 2026 | | | | | | | | | | | | | | | | Balance at beginning of period | | $ | (4,290) | | $ | (125,007) | | $ | (238,300) | | $ | (543) | | $ | (368,140) | Other comprehensive (loss) income | | | — | | | (7,813) | | | 17,318 | | | (1,158) | | | 8,347 | Balance at end of period | | $ | (4,290) | | $ | (132,820) | | $ | (220,982) | | $ | (1,701) | | $ | (359,793) | | | | | | | | | | | | | | | | | Three Months Ended June 30, 2025 | | | | | | | | | | | | | | | | Balance at beginning of period | | $ | (1,879) | | $ | (170,558) | | $ | (261,420) | | $ | 88 | | $ | (433,769) | Other comprehensive income | | | — | | | 19,324 | | | 7,319 | | | 118 | | | 26,761 | Balance at end of period | | $ | (1,879) | | $ | (151,234) | | $ | (254,101) | | $ | 206 | | $ | (407,008) | | | | | | | | | | | | | | | | | Six Months Ended June 30, 2025 | | | | | | | | | | | | | | | | Balance at beginning of period | | $ | (1,879) | | $ | (193,529) | | $ | (268,501) | | $ | (85) | | $ | (463,994) | Other comprehensive income | | | — | | | 42,295 | | | 14,400 | | | 291 | | | 56,986 | Balance at end of period | | $ | (1,879) | | $ | (151,234) | | $ | (254,101) | | $ | 206 | | $ | (407,008) | | | | | | | | | | | | | | | | |
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