Loans and Allowance for Credit Losses - Loan portfolio aging analysis (Details) $ in Thousands	Sep. 30, 2023 USD ($) loan	Jun. 30, 2023 USD ($)
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	$ 3,699,961	$ 3,619,197
Greater than 90 Days Past Due and Accruing		109
Number of PCD loans greater than 90 days past due | loan	0
Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	$ 3,671,517	3,608,456
Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	28,444	10,741
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	10,475	4,212
60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	16,233	2,767
Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,736	3,762
Residential Real Estate
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,134,604	1,133,417
Greater than 90 Days Past Due and Accruing		109
Residential Real Estate | Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,132,762	1,130,549
Residential Real Estate | Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,842	2,868
Residential Real Estate | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,221	1,984
Residential Real Estate | 60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	120	401
Residential Real Estate | Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	501	483
Construction Real Estate
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	232,892	190,856
Construction Real Estate | Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	232,364	189,404
Construction Real Estate | Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	528	1,452
Construction Real Estate | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	160	443
Construction Real Estate | 60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable		311
Construction Real Estate | Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	368	698
Commercial Real Estate
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,564,147	1,562,379
Commercial Real Estate | Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,548,712	1,558,329
Commercial Real Estate | Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	15,435	4,050
Commercial Real Estate | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	840	616
Commercial Real Estate | 60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	14,534	1,854
Commercial Real Estate | Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	61	1,580
Consumer loans
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	135,263	133,515
Consumer loans | Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	134,340	132,723
Consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	923	792
Consumer loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	592	456
Consumer loans | 60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	166	124
Consumer loans | Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	165	212
Commercial loans
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	633,055	599,030
Commercial loans | Current Loans, not past due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	623,339	597,451
Commercial loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	9,716	1,579
Commercial loans | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	7,662	713
Commercial loans | 60 to 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	1,413	77
Commercial loans | Greater than 90 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Loans Receivable	$ 641	$ 789