Loans and Allowance for Credit Losses on Loans - Major Loan Segments and Classes (Details) - USD ($) |
Mar. 31, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
Jun. 30, 2024 |
||||
|---|---|---|---|---|---|---|---|---|---|---|
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | [1],[2] | $ 1,747,703,000 | $ 1,627,406,000 | |||||||
| Allowance for credit losses on loans | (21,778,000) | $ (21,334,000) | (20,146,000) | $ (21,196,000) | $ (20,191,000) | $ (19,244,000) | ||||
| Net loans receivable | 1,725,925,000 | 1,607,260,000 | ||||||||
| Loan balances include net deferred fees/costs | (490,000) | (567,000) | ||||||||
| Accrued interest receivable | 8,000,000 | 7,000,000 | ||||||||
| Commercial Portfolio [Member] | ||||||||||
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | 134,981,000 | 116,769,000 | ||||||||
| Allowance for credit losses on loans | (2,754,000) | (2,632,000) | (2,278,000) | (2,156,000) | (2,079,000) | (2,077,000) | ||||
| Residential Real Estate [Member] | Residential Portfolio [Member] | ||||||||||
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | 415,749,000 | 417,719,000 | ||||||||
| Allowance for credit losses on loans | (4,615,000) | (4,625,000) | (4,613,000) | (4,596,000) | (4,531,000) | (4,237,000) | ||||
| Real Estate [Member] | Commercial Real Estate Portfolio [Member] | ||||||||||
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | 1,151,349,000 | 1,054,504,000 | ||||||||
| Allowance for credit losses on loans | (13,765,000) | (13,419,000) | (12,614,000) | (13,799,000) | (12,933,000) | (12,218,000) | ||||
| Home Equity [Member] | Consumer Portfolio [Member] | ||||||||||
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | 41,779,000 | 34,103,000 | ||||||||
| Allowance for credit losses on loans | (344,000) | (340,000) | (260,000) | (240,000) | (234,000) | (212,000) | ||||
| Consumer [Member] | Consumer Portfolio [Member] | ||||||||||
| Loans and Allowance for Credit Losses on Loans [Abstract] | ||||||||||
| Total gross loans | 3,845,000 | 4,311,000 | ||||||||
| Allowance for credit losses on loans | $ (300,000) | $ (318,000) | $ (381,000) | $ (405,000) | $ (414,000) | $ (500,000) | ||||
| ||||||||||