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Industry Segment Information (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Interest Income (Expense), after Provision for Loan Loss [Abstract] |  |  |  |  |
Fee revenue and other income | $ 28,843,000 | $ 28,763,000 | $ 81,829,000 | $ 85,935,000 |
Gain (Loss) on Sale of Investments | 4,000 | 0 | (3,572,000) | (13,000) |
Interest income | 25,171,000 | 22,774,000 | 72,199,000 | 65,669,000 |
Interest Expense, Operating | 4,151,000 | 5,156,000 | 12,431,000 | 15,646,000 |
Interest expense |  |  | 12,431,000 | 15,646,000 |
Intersegment expense (income) | 21,020,000 | 17,618,000 | 59,768,000 | 50,023,000 |
Tax-equivalized pre-tax income | 11,615,000 | 3,764,000 | 28,770,000 | 18,229,000 |
Income (Loss) from Discontinued Operations Including Tax Equivalent Adjustment, Before Income Taxes, Noncontrolling Interest | (141,000) |  | 5,314,000 |  |
Goodwill | 16,164,000 | 17,309,000 | 16,164,000 | 17,309,000 | $ 16,333,000
Other intangible assets, net | 4,036,000 | 2,789,000 | 4,036,000 | 2,789,000 |
Total assets | 2,453,622,000 | 2,260,760,000 | 2,453,622,000 | 2,260,760,000 | 2,395,081,000
Average funding sources | 2,212,549,000 | 2,047,491,000 | 2,141,770,000 | 2,053,972,000 |
(Release of) provision for credit losses | (193,000) | (140,000) | 737,000 | 355,000 |
Total net revenue | 50,056,000 | 46,521,000 | 140,860,000 | 135,603,000 |
Total personnel expenses | 27,606,000 | 26,522,000 | 82,637,000 | 79,673,000 |
Occupancy | 734,000 | 699,000 | 2,124,000 | 2,016,000 |
Equipment | 2,513,000 | 2,058,000 | 7,369,000 | 5,825,000 |
Bad debt expense | 0 | 6,559,000 | (2,000,000) | 7,847,000 |
Other Cost and Expense, Operating | 7,588,000 | 6,919,000 | 21,960,000 | 22,013,000 |
Operating Expenses | 38,441,000 | 42,757,000 | 112,090,000 | 117,374,000 |
Net periodic cost (benefit) | 0 | 195,000 | 0 | 581,000 |
Available-for-sale securities, gross realized gains | 351,000,000 | 0 | 351,000,000 | 0 |
Available-for-sale securities, gross realized losses | 347,000 | 0 | 3,900,000 | 13,000 |
Share-based compensation expense | 1,018,000 | 863,000 | 3,177,000 | 2,508,000 |
Supplemental Employee Retirement Plan |  |  |  |  |
Interest Income (Expense), after Provision for Loan Loss [Abstract] |  |  |  |  |
Net periodic cost (benefit) | 113,000 | 113,000 | 338,000 | 338,000 | $ 450,000
Corporate, Eliminations and Other |  |  |  |  |
Interest Income (Expense), after Provision for Loan Loss [Abstract] |  |  |  |  |
Fee revenue and other income | 679,000 | 349,000 | 1,584,000 | 1,031,000 |
Gain (Loss) on Sale of Investments | 4,000 |  | (3,572,000) | (13,000) |
Interest income | (3,953,000) | (3,079,000) | (11,281,000) | (8,691,000) |
Interest Expense, Operating | (3,894,000) | (4,183,000) |  |  |
Interest expense |  |  | (11,880,000) | (11,068,000) |
Intersegment expense (income) | 0 | 0 | 0 | 0 |
Tax-equivalized pre-tax income | 624,000 | 1,453,000 | (1,389,000) | 3,395,000 |
Income (Loss) from Discontinued Operations Including Tax Equivalent Adjustment, Before Income Taxes, Noncontrolling Interest | 0 | 0 | 0 | 0 |
Goodwill | 0 | 0 | 0 | 0 |
Other intangible assets, net | 0 | 0 | 0 | 0 |
Total assets | (311,650,000) | (282,599,000) | (311,650,000) | (282,599,000) |
Average funding sources | 0 | 0 | 0 | 0 |
(Release of) provision for credit losses | 0 | 0 | 0 | 0 |
Total net revenue | 624,000 | 1,453,000 | (1,389,000) | 3,395,000 |
Total personnel expenses | 0 | 0 | 0 | 0 |
Occupancy | 0 | 0 | 0 | 0 |
Equipment | 0 | 0 | 0 | 0 |
Bad debt expense |  | 0 | 0 | 0 |
Other Cost and Expense, Operating | 0 | 0 | 0 | 0 |
Operating Expenses | 0 | 0 | 0 | 0 |
Information services payment and processing revenue | Operating Segments |  |  |  |  |
Interest Income (Expense), after Provision for Loan Loss [Abstract] |  |  |  |  |
Fee revenue and other income | 27,491,000 | 27,800,000 | 81,845,000 | 82,998,000 |
Loss on Sale of Investments | 0 |  | 0 | 0 |
Interest income | 12,637,000 | 10,223,000 | 34,090,000 | 30,166,000 |
Interest Expense, Operating | 293,000 | 334,000 |  |  |
Interest expense |  |  | 818,000 | 1,246,000 |
Intersegment expense (income) | 865,000 | 938,000 | 2,637,000 | 2,992,000 |
Tax-equivalized pre-tax income | 6,122,000 | (322,000) | 16,376,000 | 8,124,000 |
Income (Loss) from Discontinued Operations Including Tax Equivalent Adjustment, Before Income Taxes, Noncontrolling Interest | (141,000) | (112,000) | 5,314,000 | 226,000 |
Goodwill | 16,028,000 | 17,173,000 | 16,028,000 | 17,173,000 |
Other intangible assets, net | 4,036,000 | 2,789,000 | 4,036,000 | 2,789,000 |
Total assets | 1,591,235,000 | 1,371,095,000 | 1,591,235,000 | 1,371,095,000 |
Average funding sources | 1,451,420,000 | 1,273,365,000 | 1,376,783,000 | 1,267,431,000 |
(Release of) provision for credit losses | 0 | 0 | 0 | 0 |
Total net revenue | 39,835,000 | 37,689,000 | 115,117,000 | 111,918,000 |
Total personnel expenses | 24,354,000 | 23,489,000 | 73,267,000 | 70,739,000 |
Occupancy | 534,000 | 534,000 | 1,561,000 | 1,518,000 |
Equipment | 2,453,000 | 1,808,000 | 7,175,000 | 5,077,000 |
Bad debt expense |  | 6,559,000 | (2,000,000) | 7,847,000 |
Other Cost and Expense, Operating | 5,507,000 | 4,683,000 | 16,101,000 | 15,621,000 |
Operating Expenses | 33,713,000 | 38,011,000 | 98,741,000 | 103,794,000 |
Banking Services | Operating Segments |  |  |  |  |
Interest Income (Expense), after Provision for Loan Loss [Abstract] |  |  |  |  |
Fee revenue and other income | 669,000 | 614,000 | 1,972,000 | 1,919,000 |
Loss on Sale of Investments | 0 |  | 0 | 0 |
Interest income | 16,487,000 | 15,630,000 | 49,390,000 | 44,194,000 |
Interest Expense, Operating | 7,752,000 | 9,005,000 |  |  |
Interest expense |  |  | 23,493,000 | 25,468,000 |
Intersegment expense (income) | (865,000) | (938,000) | (2,637,000) | (2,992,000) |
Tax-equivalized pre-tax income | 4,869,000 | 2,633,000 | 13,783,000 | 6,710,000 |
Income (Loss) from Discontinued Operations Including Tax Equivalent Adjustment, Before Income Taxes, Noncontrolling Interest | 0 | 0 | 0 | 0 |
Goodwill | 136,000 | 136,000 | 136,000 | 136,000 |
Other intangible assets, net | 0 | 0 | 0 | 0 |
Total assets | 1,174,037,000 | 1,172,264,000 | 1,174,037,000 | 1,172,264,000 |
Average funding sources | 761,129,000 | 774,126,000 | 764,987,000 | 786,541,000 |
(Release of) provision for credit losses | (193,000) | (140,000) | 737,000 | 355,000 |
Total net revenue | 9,597,000 | 7,379,000 | 27,132,000 | 20,290,000 |
Total personnel expenses | 3,252,000 | 3,033,000 | 9,370,000 | 8,934,000 |
Occupancy | 200,000 | 165,000 | 563,000 | 498,000 |
Equipment | 60,000 | 250,000 | 194,000 | 748,000 |
Bad debt expense |  | 0 | 0 | 0 |
Other Cost and Expense, Operating | 2,081,000 | 2,236,000 | 5,859,000 | 6,392,000 |
Operating Expenses | $ 4,728,000 | $ 4,746,000 | $ 13,349,000 | $ 13,580,000 |

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