Loans - Loan Balances Based on Year of Origination (Details) $ in Thousands	Mar. 31, 2023 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Gross charge-offs - fiscal year 2023	$ 73
Gross charge-offs - fiscal year 2022	13
Gross charge-offs - fiscal year 2021	7
Gross charge-offs - fiscal year 2020	29
Gross charge-offs - Term Total	122
Gross charge-offs - Grand Total	122
Consumer Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	23,642
2022	103,775
2021	99,363
2020	88,874
Prior	142,193
Term Total	457,847
Revolving Loans Amortized Cost Basis	45,121
Grand Total	502,968
Consumer Real Estate [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	23,642
2022	103,775
2021	98,956
2020	88,874
Prior	140,856
Term Total	456,103
Revolving Loans Amortized Cost Basis	45,103
Grand Total	501,206
Consumer Real Estate [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Prior	559
Term Total	559
Grand Total	559
Consumer Real Estate [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2021	407
Prior	778
Term Total	1,185
Revolving Loans Amortized Cost Basis	18
Grand Total	1,203
Agricultural Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	12,810
2022	41,101
2021	40,232
2020	27,601
Prior	105,758
Term Total	227,502
Revolving Loans Amortized Cost Basis	97
Grand Total	227,599
Agricultural Real Estate [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	12,810
2022	40,851
2021	38,036
2020	27,066
Prior	91,794
Term Total	210,557
Revolving Loans Amortized Cost Basis	97
Grand Total	210,654
Agricultural Real Estate [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2021	686
2020	346
Prior	6,947
Term Total	7,979
Grand Total	7,979
Agricultural Real Estate [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	250
2021	1,510
2020	189
Prior	7,017
Term Total	8,966
Grand Total	8,966
Agricultural [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	11,106
2022	28,922
2021	12,985
2020	5,517
Prior	7,226
Term Total	65,756
Revolving Loans Amortized Cost Basis	65,921
Grand Total	131,677
Agricultural [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	11,106
2022	28,922
2021	12,985
2020	5,433
Prior	7,226
Term Total	65,672
Revolving Loans Amortized Cost Basis	65,920
Grand Total	131,592
Agricultural [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Revolving Loans Amortized Cost Basis	1
Grand Total	1
Agricultural [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	84
Term Total	84
Grand Total	84
Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	90,041
2022	440,755
2021	262,208
2020	142,221
Prior	287,938
Term Total	1,223,163
Grand Total	1,223,163
Commercial Real Estate [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	89,943
2022	440,142
2021	262,208
2020	131,449
Prior	265,358
Term Total	1,189,100
Grand Total	1,189,100
Commercial Real Estate [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2020	10,697
Prior	1,292
Term Total	11,989
Grand Total	11,989
Commercial Real Estate [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	98
2022	613
2020	75
Prior	21,288
Term Total	22,074
Grand Total	22,074
Commercial & Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	17,761
2022	63,566
2021	34,636
2020	30,431
Prior	7,493
Term Total	153,887
Revolving Loans Amortized Cost Basis	87,647
Grand Total	241,534
Commercial & Industrial [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	17,561
2022	63,073
2021	33,720
2020	29,328
Prior	6,634
Term Total	150,316
Revolving Loans Amortized Cost Basis	85,496
Grand Total	235,812
Commercial & Industrial [Member] \| Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	200
2021	221
2020	159
Prior	481
Term Total	1,061
Revolving Loans Amortized Cost Basis	195
Grand Total	1,256
Commercial & Industrial [Member] \| Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	493
2021	695
2020	944
Prior	378
Term Total	2,510
Revolving Loans Amortized Cost Basis	1,956
Grand Total	4,466
Consumer [Member] \| Payment Performance [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	8,901
2022	53,708
2021	15,170
2020	7,780
Prior	4,778
Term Total	90,337
Revolving Loans Amortized Cost Basis	51
Grand Total	90,388
Consumer [Member] \| Performing [Member] \| Payment Performance [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2023	8,901
2022	53,708
2021	15,151
2020	7,780
Prior	4,776
Term Total	90,316
Revolving Loans Amortized Cost Basis	51
Grand Total	90,367
Consumer [Member] \| Nonperforming [Member] \| Payment Performance [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2021	19
Prior	2
Term Total	21
Grand Total	21
Other Loan [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	200
2021	17,526
2020	6,341
Prior	5,256
Term Total	29,323
Grand Total	29,323
Other Loan [Member] \| Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
2022	200
2021	17,526
2020	6,341
Prior	5,256
Term Total	29,323
Grand Total	$ 29,323

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Financing receivable allowance for credit losses writeoffs fiscal year before current fiscal year.

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Financing receivable term loan.

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Amortized cost of financing receivable originated in current fiscal year. Excludes net investment in lease.

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