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Loans Receivable, Allowance for Credit Losses and Credit Quality - Loans Receivable by Internal Risk Grade by Year of Origination (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | $ 408,830 | $ 492,728 |  | $ 408,830 |
2024 / 2023 | 504,699 | 943,600 |  | 504,699 |
2023 / 2022 | 912,500 | 1,057,604 |  | 912,500 |
2022 / 2021 | 975,329 | 446,009 |  | 975,329 |
2021 / 2020 | 421,230 | 275,740 |  | 421,230 |
Prior | 781,927 | 568,097 |  | 781,927 |
Revolving Loans | 718,436 | 555,690 |  | 718,436 |
Total | 4,722,951 | 4,339,468 |  | 4,722,951 |
Incurred Loss Model - Nonaccrual Loans | 0 |  | $ 0 | 0 | $ 0
Current period gross charge-offs |  |  |  |  |
2024 / 2023 | 22 | 136 |  |  |
2023 / 2022 | 11 | 388 |  |  |
2022 / 2021 | 365 | 165 |  |  |
2021 / 2020 | 214 | 100 |  |  |
Prior | 51 | 45 |  |  |
Revolving Loans | 30 | 10 |  |  |
Total | 693 | 844 | 5,305 | 3,441 | 8,191
Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 356,959 | 425,299 |  | 356,959 |
2024 / 2023 | 450,484 | 911,367 |  | 450,484 |
2023 / 2022 | 803,521 | 988,187 |  | 803,521 |
2022 / 2021 | 855,053 | 390,953 |  | 855,053 |
2021 / 2020 | 367,766 | 264,475 |  | 367,766 |
Prior | 745,168 | 537,982 |  | 745,168 |
Revolving Loans | 707,034 | 547,216 |  | 707,034 |
Total | 4,285,985 | 4,065,479 |  | 4,285,985 |
Special Mention |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 81,743 | 1,930 |  | 81,743 |
2022 / 2021 | 62,452 | 5,548 |  | 62,452 |
2021 / 2020 | 7,070 | 1,875 |  | 7,070 |
Prior | 4,961 | 3,220 |  | 4,961 |
Revolving Loans | 2,367 | 425 |  | 2,367 |
Total | 158,593 | 12,998 |  | 158,593 |
Substandard |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 11 | 469 |  | 11 |
2022 / 2021 | 1,740 | 246 |  | 1,740 |
2021 / 2020 | 254 | 343 |  | 254 |
Prior | 7,177 | 9,740 |  | 7,177 |
Revolving Loans | 5,922 | 5,625 |  | 5,922 |
Total | 15,104 | 16,423 |  | 15,104 |
Doubtful |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Prior | 10 | 10 |  | 10 |
Total | 10 | 10 |  | 10 |
Not Formally Risk Related |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 51,871 | 67,429 |  | 51,871 |
2024 / 2023 | 54,215 | 32,233 |  | 54,215 |
2023 / 2022 | 27,225 | 67,018 |  | 27,225 |
2022 / 2021 | 56,084 | 49,262 |  | 56,084 |
2021 / 2020 | 46,140 | 9,047 |  | 46,140 |
Prior | 24,611 | 17,145 |  | 24,611 |
Revolving Loans | 3,113 | 2,424 |  | 3,113 |
Total | 263,259 | 244,558 |  | 263,259 |
Residential real estate |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Total | 1,272,835 | 1,254,832 |  | 1,272,835 |
Residential real estate | One to four-family residential |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 68,875 | 97,895 |  | 68,875 |
2024 / 2023 | 101,033 | 145,711 |  | 101,033 |
2023 / 2022 | 138,257 | 266,364 |  | 138,257 |
2022 / 2021 | 252,612 | 248,045 |  | 252,612 |
2021 / 2020 | 231,320 | 115,133 |  | 231,320 |
Prior | 307,731 | 227,344 |  | 307,731 |
Revolving Loans | 34,028 | 30,299 |  | 34,028 |
Total | 1,133,856 | 1,130,791 |  | 1,133,856 |
Residential real estate | One to four-family residential | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 68,875 | 97,895 |  | 68,875 |
2024 / 2023 | 101,033 | 145,711 |  | 101,033 |
2023 / 2022 | 138,257 | 266,364 |  | 138,257 |
2022 / 2021 | 252,612 | 247,799 |  | 252,612 |
2021 / 2020 | 231,078 | 115,133 |  | 231,078 |
Prior | 305,439 | 224,354 |  | 305,439 |
Revolving Loans | 33,790 | 30,227 |  | 33,790 |
Total | 1,131,084 | 1,127,483 |  | 1,131,084 |
Residential real estate | One to four-family residential | Substandard |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2022 / 2021 |  | 246 |  |  |
2021 / 2020 | 242 |  |  | 242 |
Prior | 2,292 | 2,990 |  | 2,292 |
Revolving Loans | 238 | 72 |  | 238 |
Total | 2,772 | 3,308 |  | 2,772 |
Residential real estate | Home Equity |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 245 |  |  | 245 |
Revolving Loans | 138,734 | 124,041 |  | 138,734 |
Total | 138,979 | 124,041 |  | 138,979 |
Residential real estate | Home Equity | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 245 |  |  | 245 |
Revolving Loans | 137,562 | 123,083 |  | 137,562 |
Total | 137,807 | 123,083 |  | 137,807 |
Residential real estate | Home Equity | Substandard |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Revolving Loans | 1,172 | 958 |  | 1,172 |
Total | 1,172 | 958 |  | 1,172 |
Residential real estate | Commercial |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 181,156 | 118,115 |  | 181,156 |
2024 / 2023 | 109,979 | 409,048 |  | 109,979 |
2023 / 2022 | 352,415 | 366,252 |  | 352,415 |
2022 / 2021 | 328,413 | 72,013 |  | 328,413 |
2021 / 2020 | 69,885 | 98,373 |  | 69,885 |
Prior | 339,539 | 254,505 |  | 339,539 |
Revolving Loans | 68,288 | 45,088 |  | 68,288 |
Total | 1,449,675 | 1,363,394 |  | 1,449,675 |
Current period gross charge-offs |  |  |  |  |
Total |  |  | 4,000 |  | 4,000
Residential real estate | Commercial | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 181,156 | 118,115 |  | 181,156 |
2024 / 2023 | 109,979 | 409,048 |  | 109,979 |
2023 / 2022 | 270,672 | 364,384 |  | 270,672 |
2022 / 2021 | 278,879 | 69,349 |  | 278,879 |
2021 / 2020 | 65,442 | 97,500 |  | 65,442 |
Prior | 335,176 | 248,749 |  | 335,176 |
Revolving Loans | 66,546 | 45,088 |  | 66,546 |
Total | 1,307,850 | 1,352,233 |  | 1,307,850 |
Residential real estate | Commercial | Special Mention |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 81,743 | 1,399 |  | 81,743 |
2022 / 2021 | 47,917 | 2,664 |  | 47,917 |
2021 / 2020 | 4,443 | 873 |  | 4,443 |
Prior | 4,015 | 3,220 |  | 4,015 |
Revolving Loans | 1,742 |  |  | 1,742 |
Total | 139,860 | 8,156 |  | 139,860 |
Residential real estate | Commercial | Substandard |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 |  | 469 |  |  |
2022 / 2021 | 1,617 |  |  | 1,617 |
Prior | 348 | 2,536 |  | 348 |
Total | 1,965 | 3,005 |  | 1,965 |
Residential real estate | Multi-family residential |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 17,538 | 5,138 |  | 17,538 |
2024 / 2023 | 6,083 | 7,563 |  | 6,083 |
2023 / 2022 | 72,966 | 212,492 |  | 72,966 |
2022 / 2021 | 227,584 | 21,791 |  | 227,584 |
2021 / 2020 | 18,270 | 36,016 |  | 18,270 |
Prior | 83,784 | 50,047 |  | 83,784 |
Revolving Loans | 4,203 |  |  | 4,203 |
Total | 430,428 | 333,047 |  | 430,428 |
Residential real estate | Multi-family residential | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 17,538 | 5,138 |  | 17,538 |
2024 / 2023 | 6,083 | 7,563 |  | 6,083 |
2023 / 2022 | 72,966 | 212,492 |  | 72,966 |
2022 / 2021 | 227,584 | 21,791 |  | 227,584 |
2021 / 2020 | 18,270 | 36,016 |  | 18,270 |
Prior | 83,784 | 50,047 |  | 83,784 |
Revolving Loans | 4,203 |  |  | 4,203 |
Total | 430,428 | 333,047 |  | 430,428 |
Residential real estate | Construction & Land Development |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 51,715 | 161,997 |  | 51,715 |
2024 / 2023 | 195,481 | 284,102 |  | 195,481 |
2023 / 2022 | 259,138 | 90,512 |  | 259,138 |
2022 / 2021 | 50,405 | 13,255 |  | 50,405 |
2021 / 2020 | 16,143 | 9,232 |  | 16,143 |
Prior | 1,336 | 374 |  | 1,336 |
Revolving Loans | 80,805 | 24,337 |  | 80,805 |
Total | 655,023 | 583,809 |  | 655,023 |
Residential real estate | Construction & Land Development | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 51,715 | 161,997 |  | 51,715 |
2024 / 2023 | 195,481 | 284,102 |  | 195,481 |
2023 / 2022 | 259,138 | 90,512 |  | 259,138 |
2022 / 2021 | 38,822 | 13,255 |  | 38,822 |
2021 / 2020 | 16,143 | 9,232 |  | 16,143 |
Prior | 1,326 | 364 |  | 1,326 |
Revolving Loans | 80,805 | 24,337 |  | 80,805 |
Total | 643,430 | 583,799 |  | 643,430 |
Residential real estate | Construction & Land Development | Special Mention |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2022 / 2021 | 11,583 |  |  | 11,583 |
Total | 11,583 |  |  | 11,583 |
Residential real estate | Construction & Land Development | Doubtful |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Prior | 10 | 10 |  | 10 |
Total | 10 | 10 |  | 10 |
Commercial |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Total | 3,186,857 | 2,840,078 |  | 3,186,857 |
Commercial | Construction & Land Development |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
Total | 655,023 | 583,809 |  | 655,023 |
Commercial | Commercial and industrial |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 37,675 | 42,154 |  | 37,675 |
2024 / 2023 | 37,908 | 64,943 |  | 37,908 |
2023 / 2022 | 62,254 | 54,966 |  | 62,254 |
2022 / 2021 | 60,231 | 41,643 |  | 60,231 |
2021 / 2020 | 39,472 | 7,939 |  | 39,472 |
Prior | 24,926 | 18,682 |  | 24,926 |
Revolving Loans | 389,265 | 329,501 |  | 389,265 |
Total | 651,731 | 559,828 |  | 651,731 |
Current period gross charge-offs |  |  |  |  |
Total |  |  |  |  | 391
Commercial | Commercial and industrial | Pass |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 37,675 | 42,154 |  | 37,675 |
2024 / 2023 | 37,908 | 64,943 |  | 37,908 |
2023 / 2022 | 62,243 | 54,435 |  | 62,243 |
2022 / 2021 | 57,156 | 38,759 |  | 57,156 |
2021 / 2020 | 36,833 | 6,594 |  | 36,833 |
Prior | 19,443 | 14,468 |  | 19,443 |
Revolving Loans | 384,128 | 324,481 |  | 384,128 |
Total | 635,386 | 545,834 |  | 635,386 |
Commercial | Commercial and industrial | Special Mention |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 |  | 531 |  |  |
2022 / 2021 | 2,952 | 2,884 |  | 2,952 |
2021 / 2020 | 2,627 | 1,002 |  | 2,627 |
Prior | 946 |  |  | 946 |
Revolving Loans | 625 | 425 |  | 625 |
Total | 7,150 | 4,842 |  | 7,150 |
Commercial | Commercial and industrial | Substandard |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2023 / 2022 | 11 |  |  | 11 |
2022 / 2021 | 123 |  |  | 123 |
2021 / 2020 | 12 | 343 |  | 12 |
Prior | 4,537 | 4,214 |  | 4,537 |
Revolving Loans | 4,512 | 4,595 |  | 4,512 |
Total | 9,195 | 9,152 |  | 9,195 |
Consumer |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 51,871 | 67,429 |  | 51,871 |
2024 / 2023 | 54,215 | 32,233 |  | 54,215 |
2023 / 2022 | 27,225 | 67,018 |  | 27,225 |
2022 / 2021 | 56,084 | 49,262 |  | 56,084 |
2021 / 2020 | 46,140 | 9,047 |  | 46,140 |
Prior | 24,611 | 17,145 |  | 24,611 |
Revolving Loans | 3,113 | 2,424 |  | 3,113 |
Total | 263,259 | 244,558 |  | 263,259 |
Incurred Loss Model - Nonaccrual Loans | 2,100 | 2,400 |  | 2,100 |
Current period gross charge-offs |  |  |  |  |
2024 / 2023 | 22 | 136 |  |  |
2023 / 2022 | 11 | 388 |  |  |
2022 / 2021 | 365 | 165 |  |  |
2021 / 2020 | 214 | 100 |  |  |
Prior | 51 | 45 |  |  |
Revolving Loans | 30 | 10 |  |  |
Total | 693 | 844 | $ 1,305 | 3,441 | $ 3,800
Consumer | Not Formally Risk Related |  |  |  |  |
Term Loans Amortized Cost Basis by Origination Year |  |  |  |  |
2025 / 2024 | 51,871 | 67,429 |  | 51,871 |
2024 / 2023 | 54,215 | 32,233 |  | 54,215 |
2023 / 2022 | 27,225 | 67,018 |  | 27,225 |
2022 / 2021 | 56,084 | 49,262 |  | 56,084 |
2021 / 2020 | 46,140 | 9,047 |  | 46,140 |
Prior | 24,611 | 17,145 |  | 24,611 |
Revolving Loans | 3,113 | 2,424 |  | 3,113 |
Total | $ 263,259 | $ 244,558 |  | $ 263,259 |

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