Loans and Allowance for Credit Losses - Classes of loans (Details) $ in Thousands	9 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) loan	Jun. 30, 2023 USD ($) loan	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	$ 3,998,414	$ 3,978,393
Loans in Process	(226,969)	(359,196)
Deferred loan fees, net	(251)	(299)
Allowance for credit losses	(51,336)	(47,820)	$ (50,084)	$ (45,685)	$ (37,483)	$ (33,192)
Total loans	$ 3,719,858	$ 3,571,078
Number of purchased participation loans | loan	69	86
Purchased participation loans	$ 174,600	$ 155,600
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	1,200,723	1,133,417
Allowance for credit losses	(15,357)	(15,641)	(15,096)	(13,465)	(12,499)	(8,908)
Construction Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	432,030	550,052
Allowance for credit losses	(2,347)	(2,664)	(2,864)	(3,638)	(2,754)	(2,220)
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	1,608,935	1,562,379
Allowance for credit losses	(26,610)	(22,838)	(25,177)	(18,545)	(16,806)	(16,838)
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	140,123	133,515
Allowance for credit losses	(900)	(909)	(890)	(986)	(761)	(710)
Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans before fees gross	616,603	599,030
Allowance for credit losses	$ (6,122)	$ (5,768)	$ (6,057)	$ (9,051)	$ (4,663)	$ (4,516)