| Financing Receivable, Past Due [Table Text Block] |
| | | As of June 30, 2026 | |
| | | 1-59 Days Past Due (1) | | | 60-89 Days Past Due (2) | | | 90 Days or Greater | | | Total Past Due | | | Current (3) | | | Total Loans | |
| | | (In Thousands) | |
| Mortgage loans: | | | | | | | | | | | | | | | | | | | | | | | | |
| Residential real estate: | | | | | | | | | | | | | | | | | | | | | | | | |
| One- to four-family | | $ | 4,077 | | | $ | 1,030 | | | $ | 4,059 | | | $ | 9,166 | | | $ | 451,329 | | | $ | 460,495 | |
| Multi-family | | | 454 | | | | - | | | | 239 | | | | 693 | | | | 781,167 | | | | 781,860 | |
| Home equity | | | 20 | | | | - | | | | - | | | | 20 | | | | 12,919 | | | | 12,939 | |
| Construction and land | | | - | | | | - | | | | - | | | | - | | | | 67,944 | | | | 67,944 | |
| Commercial real estate | | | 217 | | | | 452 | | | | - | | | | 669 | | | | 323,704 | | | | 324,373 | |
| Consumer | | | - | | | | - | | | | - | | | | - | | | | 680 | | | | 680 | |
| Commercial loans | | | 75 | | | | - | | | | - | | | | 75 | | | | 35,515 | | | | 35,590 | |
| Total | | $ | 4,843 | | | $ | 1,482 | | | $ | 4,298 | | | $ | 10,623 | | | $ | 1,673,258 | | | $ | 1,683,881 | |
| | | As of December 31, 2025 | |
| | | 1-59 Days Past Due (1) | | | 60-89 Days Past Due (2) | | | 90 Days or Greater | | | Total Past Due | | | Current (3) | | | Total Loans | |
| | | (In Thousands) | |
| Mortgage loans: | | | | | | | | | | | | | | | | | | | | | | | | |
| Residential real estate: | | | | | | | | | | | | | | | | | | | | | | | | |
| One- to four-family | | $ | 6,072 | | | $ | 2,327 | | | $ | 4,832 | | | $ | 13,231 | | | $ | 472,841 | | | $ | 486,072 | |
| Multi-family | | | 240 | | | | - | | | | - | | | | 240 | | | | 758,169 | | | | 758,409 | |
| Home equity | | | 706 | | | | - | | | | - | | | | 706 | | | | 12,507 | | | | 13,213 | |
| Construction and land | | | - | | | | - | | | | - | | | | - | | | | 56,340 | | | | 56,340 | |
| Commercial real estate | | | 230 | | | | - | | | | - | | | | 230 | | | | 327,116 | | | | 327,346 | |
| Consumer | | | - | | | | - | | | | - | | | | - | | | | 801 | | | | 801 | |
| Commercial loans | | | - | | | | - | | | | - | | | | - | | | | 33,371 | | | | 33,371 | |
| Total | | $ | 7,248 | | | $ | 2,327 | | | $ | 4,832 | | | $ | 14,407 | | | $ | 1,661,145 | | | $ | 1,675,552 | |
|
| Financing Receivable, Allowance for Credit Loss [Table Text Block] |
| | | One- to Four-Family | | | Multi-Family | | | Home Equity | | | Land and Construction | | | Commercial Real Estate | | | Consumer | | | Commercial | | | Total | |
| | | (In Thousands) | |
| Six months ended June 30, 2026 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Balance at beginning of period | | $ | 4,916 | | | $ | 6,948 | | | $ | 201 | | | $ | 932 | | | $ | 4,114 | | | $ | 77 | | | $ | 290 | | | $ | 17,478 | |
| Provision (credit) for credit losses - loans | | | (517 | ) | | | 726 | | | | (58 | ) | | | 121 | | | | 100 | | | | 2 | | | | 5 | | | | 379 | |
| Charge-offs | | | - | | | | - | | | | - | | | | - | | | | - | | | | (15 | ) | | | - | | | | (15 | ) |
| Recoveries | | | 36 | | | | 3 | | | | - | | | | 2 | | | | - | | | | 1 | | | | - | | | | 42 | |
| Balance at end of period | | $ | 4,435 | | | $ | 7,677 | | | $ | 143 | | | $ | 1,055 | | | $ | 4,214 | | | $ | 65 | | | $ | 295 | | | $ | 17,884 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Six months ended June 30, 2025 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Balance at beginning of period | | $ | 5,286 | | | $ | 7,079 | | | $ | 212 | | | $ | 1,205 | | | $ | 3,920 | | | $ | 79 | | | $ | 466 | | | $ | 18,247 | |
| Provision (credit) for credit losses - loans | | | (213 | ) | | | (424 | ) | | | (15 | ) | | | (26 | ) | | | 267 | | | | 15 | | | | (73 | ) | | | (469 | ) |
| Charge-offs | | | - | | | | - | | | | - | | | | - | | | | - | | | | (25 | ) | | | - | | | | (25 | ) |
| Recoveries | | | 37 | | | | - | | | | - | | | | 2 | | | | - | | | | 8 | | | | - | | | | 47 | |
| Balance at end of period | | $ | 5,110 | | | $ | 6,655 | | | $ | 197 | | | $ | 1,181 | | | $ | 4,187 | | | $ | 77 | | | $ | 393 | | | $ | 17,800 | |
| | | One to-Four- Family | | | Multi-Family | | | Home Equity | | | Construction and Land | | | Commercial Real Estate | | | Consumer | | | Commercial | | | Total | |
| | | (In Thousands) | |
| Three months ended June 30, 2026 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Balance at beginning of period | | $ | 4,446 | | | $ | 7,599 | | | $ | 163 | | | $ | 1,055 | | | $ | 4,078 | | | $ | 69 | | | $ | 299 | | | $ | 17,709 | |
| Provision (credit) for credit losses - loans | | | (27 | ) | | | 78 | | | | (20 | ) | | | (1 | ) | | | 136 | | | | (3 | ) | | | (4 | ) | | | 159 | |
| Charge-offs | | | - | | | | - | | | | - | | | | - | | | | - | | | | (1 | ) | | | - | | | | (1 | ) |
| Recoveries | | | 16 | | | | - | | | | - | | | | 1 | | | | - | | | | - | | | | - | | | | 17 | |
| Balance at end of period | | $ | 4,435 | | | $ | 7,677 | | | $ | 143 | | | $ | 1,055 | | | $ | 4,214 | | | $ | 65 | | | $ | 295 | | | $ | 17,884 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Three months ended June 30, 2025 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Balance at beginning of period | | $ | 4,979 | | | $ | 6,938 | | | $ | 193 | | | $ | 1,042 | | | $ | 4,173 | | | $ | 77 | | | $ | 503 | | | $ | 17,905 | |
| Provision (credit) for credit losses - loans | | | 126 | | | | (283 | ) | | | 4 | | | | 138 | | | | 14 | | | | (4 | ) | | | (110 | ) | | | (115 | ) |
| Charge-offs | | | - | | | | - | | | | - | | | | - | | | | - | | | | (4 | ) | | | - | | | | (4 | ) |
| Recoveries | | | 5 | | | | - | | | | - | | | | 1 | | | | - | | | | 8 | | | | - | | | | 14 | |
| Balance at end of period | | $ | 5,110 | | | $ | 6,655 | | | $ | 197 | | | $ | 1,181 | | | $ | 4,187 | | | $ | 77 | | | $ | 393 | | | $ | 17,800 | |
|
| Financing Receivable Credit Quality Indicators [Table Text Block] |
| | | One to Four-Family | | | Multi-Family | | | Home Equity | | | Construction and Land | | | Commercial Real Estate | | | Consumer | | | Commercial | | | Total | |
| | | (In Thousands) | |
| At June 30, 2026 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Substandard | | $ | 6,179 | | | $ | 239 | | | $ | - | | | $ | - | | | $ | 11,152 | | | $ | - | | | $ | - | | | $ | 17,570 | |
| Watch | | | 5,924 | | | | - | | | | - | | | | - | | | | 805 | | | | - | | | | 1,227 | | | | 7,956 | |
| Pass | | | 448,392 | | | | 781,621 | | | | 12,939 | | | | 67,944 | | | | 312,416 | | | | 680 | | | | 34,363 | | | | 1,658,355 | |
| | | $ | 460,495 | | | $ | 781,860 | | | $ | 12,939 | | | $ | 67,944 | | | $ | 324,373 | | | $ | 680 | | | $ | 35,590 | | | $ | 1,683,881 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| At December 31, 2025 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Substandard | | $ | 5,861 | | | $ | 177 | | | $ | 14 | | | $ | - | | | $ | 11,282 | | | $ | - | | | $ | - | | | $ | 17,334 | |
| Watch | | | 9,831 | | | | - | | | | 69 | | | | - | | | | 424 | | | | - | | | | 1,437 | | | | 11,761 | |
| Pass | | | 470,380 | | | | 758,232 | | | | 13,130 | | | | 56,340 | | | | 315,640 | | | | 801 | | | | 31,934 | | | | 1,646,457 | |
| | | $ | 486,072 | | | $ | 758,409 | | | $ | 13,213 | | | $ | 56,340 | | | $ | 327,346 | | | $ | 801 | | | $ | 33,371 | | | $ | 1,675,552 | |
| | | 2026 | | | 2025 | | | 2024 | | | 2023 | | | 2022 | | | Prior | | | Revolving | | | Total | |
| | | (In Thousands) | |
| One- to four-family | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | $ | 21,934 | | | $ | 25,549 | | | $ | 27,643 | | | $ | 142,072 | | | $ | 126,698 | | | $ | 103,444 | | | $ | 1,052 | | | $ | 448,392 | |
| Watch | | | 4,757 | | | | - | | | | 42 | | | | - | | | | 452 | | | | 673 | | | | - | | | | 5,924 | |
| Substandard | | | 2,229 | | | | 1,335 | | | | - | | | | 583 | | | | 443 | | | | 1,589 | | | | - | | | | 6,179 | |
| Total | | | 28,920 | | | | 26,884 | | | | 27,685 | | | | 142,655 | | | | 127,593 | | | | 105,706 | | | | 1,052 | | | | 460,495 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Multi-family | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 104,026 | | | | 195,909 | | | | 38,118 | | | | 104,468 | | | | 145,135 | | | | 192,668 | | | | 1,297 | | | $ | 781,621 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | 239 | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 239 | |
| Total | | | 104,265 | | | | 195,909 | | | | 38,118 | | | | 104,468 | | | | 145,135 | | | | 192,668 | | | | 1,297 | | | | 781,860 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Home equity | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 35 | | | | 550 | | | | 265 | | | | 353 | | | | 1,488 | | | | 195 | | | | 10,053 | | | $ | 12,939 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | 35 | | | | 550 | | | | 265 | | | | 353 | | | | 1,488 | | | | 195 | | | | 10,053 | | | | 12,939 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Construction and land | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 138 | | | | 27,254 | | | | 40,400 | | | | - | | | | 138 | | | | 14 | | | | - | | | $ | 67,944 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | 138 | | | | 27,254 | | | | 40,400 | | | | - | | | | 138 | | | | 14 | | | | - | | | | 67,944 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial Real Estate | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 52,233 | | | | 53,771 | | | | 54,396 | | | | 35,747 | | | | 39,405 | | | | 74,935 | | | | 1,929 | | | $ | 312,416 | |
| Watch | | | - | | | | 578 | | | | - | | | | 227 | | | | - | | | | - | | | | - | | | | 805 | |
| Substandard | | | 11,034 | | | | 118 | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 11,152 | |
| Total | | | 63,267 | | | | 54,467 | | | | 54,396 | | | | 35,974 | | | | 39,405 | | | | 74,935 | | | | 1,929 | | | | 324,373 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Consumer | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 680 | | | $ | 680 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 680 | | | | 680 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 1,280 | | | | 3,507 | | | | 233 | | | | 16,114 | | | | 612 | | | | 1,396 | | | | 11,221 | | | $ | 34,363 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | 2 | | | | - | | | | 1,225 | | | | 1,227 | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | 1,280 | | | | 3,507 | | | | 233 | | | | 16,114 | | | | 614 | | | | 1,396 | | | | 12,446 | | | | 35,590 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Total Loans | | $ | 197,905 | | | $ | 308,571 | | | $ | 161,097 | | | $ | 299,564 | | | $ | 314,373 | | | $ | 374,914 | | | $ | 27,457 | | | $ | 1,683,881 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Gross charge-offs | | $ | - | | | $ | - | | | $ | - | | | $ | - | | | $ | - | | | $ | - | | | $ | 15 | | | $ | 15 | |
| | | 2025 | | | 2024 | | | 2023 | | | 2022 | | | 2021 | | | Prior | | | Revolving | | | Total | |
| | | (In Thousands) | |
| One- to four-family | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | $ | 26,575 | | | $ | 29,945 | | | $ | 154,904 | | | $ | 138,715 | | | $ | 35,632 | | | $ | 83,320 | | | $ | 1,289 | | | $ | 470,380 | |
| Watch | | | 6,261 | | | | 44 | | | | 458 | | | | 1,720 | | | | - | | | | 1,348 | | | | - | | | | 9,831 | |
| Substandard | | | 2,373 | | | | 523 | | | | 1,036 | | | | 540 | | | | - | | | | 1,389 | | | | - | | | | 5,861 | |
| Total | | | 35,209 | | | | 30,512 | | | | 156,398 | | | | 140,975 | | | | 35,632 | | | | 86,057 | | | | 1,289 | | | | 486,072 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Multi-family | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 199,544 | | | | 62,973 | | | | 111,186 | | | | 149,108 | | | | 102,220 | | | | 132,675 | | | | 526 | | | $ | 758,232 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | 177 | | | | - | | | | - | | | | - | | | | - | | | | 177 | |
| Total | | | 199,544 | | | | 62,973 | | | | 111,363 | | | | 149,108 | | | | 102,220 | | | | 132,675 | | | | 526 | | | | 758,409 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Home equity | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 564 | | | | 352 | | | | 368 | | | | 1,533 | | | | 67 | | | | 151 | | | | 10,095 | | | $ | 13,130 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 69 | | | | 69 | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | 14 | | | | - | | | | - | | | | 14 | |
| Total | | | 564 | | | | 352 | | | | 368 | | | | 1,533 | | | | 81 | | | | 151 | | | | 10,164 | | | | 13,213 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Construction and land | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 14,937 | | | | 37,521 | | | | 3,728 | | | | 139 | | | | - | | | | 15 | | | | - | | | $ | 56,340 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | 14,937 | | | | 37,521 | | | | 3,728 | | | | 139 | | | | - | | | | 15 | | | | - | | | | 56,340 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial Real Estate | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 63,935 | | | | 56,767 | | | | 61,258 | | | | 41,542 | | | | 53,097 | | | | 34,788 | | | | 4,253 | | | $ | 315,640 | |
| Watch | | | 194 | | | | - | | | | 230 | | | | - | | | | - | | | | - | | | | - | | | | 424 | |
| Substandard | | | 11,282 | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 11,282 | |
| Total | | | 75,411 | | | | 56,767 | | | | 61,488 | | | | 41,542 | | | | 53,097 | | | | 34,788 | | | | 4,253 | | | | 327,346 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Consumer | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 801 | | | $ | 801 | |
| Watch | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | 801 | | | | 801 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Commercial | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Pass | | | 3,972 | | | | 533 | | | | 16,407 | | | | 785 | | | | 322 | | | | 1,300 | | | | 8,615 | | | $ | 31,934 | |
| Watch | | | - | | | | - | | | | - | | | | 11 | | | | - | | | | - | | | | 1,426 | | | | 1,437 | |
| Substandard | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | | | | - | |
| Total | | | 3,972 | | | | 533 | | | | 16,407 | | | | 796 | | | | 322 | | | | 1,300 | | | | 10,041 | | | | 33,371 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| Total Loans | | $ | 329,637 | | | $ | 188,658 | | | $ | 349,752 | | | $ | 334,093 | | | $ | 191,352 | | | $ | 254,986 | | | $ | 27,074 | | | $ | 1,675,552 | |
|