The useful life of the loan receivable.

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The ratio used to analyze the amount of debt that can be supported by the cash flow generated from the property. The calculation is the net income generated by the property divided by the commercial mortgage payment.

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The amount of the mortgage loan as a percentage of the total appraised value of the real property. Loan-to-value is one of the key risk factors that lenders assess when qualifying borrowers for a mortgage.

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Loans and leases receivable, interest receivable.

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The allowance for loan losses related to financing receivables that have been modified by troubled debt restructurings.

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Specifies the time period covered by the loan receivable.

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Minimum value of loans individually measured for impairment.

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No definition available.

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Number of alternatives for measuring impaired loans receivable.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

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Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The increase (decrease) during the reporting period of the sum of amounts due within one year (or one business cycle) from customers for the credit sale of goods and services; and from note holders for outstanding loans.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Loans and Allowance for Credit Losses - Additional Information (Details)	6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) alternative Loan_modified	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) Loan_modified
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest on loans	$ 16,900,000		$ 14,700,000
Minimum value of loans individually measured for impairment	$ 250,000
Number of alternatives for measuring impaired loans receivable \| alternative	3
Interest lost on nonaccrual loans	$ 94,000	$ 319,000
Troubled debt restructurings balance	5,012,000		5,792,000
Loans receivable, modifications, allowance	$ 497,000		$ 765,000
Troubled debt restructurings balance \| Loan_modified	2		1
Real estate acquired through foreclosure	$ 4,209,000		$ 4,984,000
Mortgage loans secured by real estate In foreclosure	$ 417,000		411,000
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amortization period of loans	25 years
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt coverage ratio	1.20x
Commercial Real Estate \| Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	65.00%
Amortization period of loans	20 years
Commercial Real Estate \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
1-4 Family Residential Properties
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Motels and Hotels Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 203,000,000.0
Non-residential Buildings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	902,000,000.0
Residential Buildings and Dwellings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	494,500,000
Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Troubled debt restructurings balance	$ 4,489,000		4,953,000
Unsecured Open-end Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	180 days
Other Secured Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period when loans charged-down	120 days
Agricultural
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 492,600,000		430,800,000
Increase (decrease) in accounts and notes receivable	$ 61,800,000
Maximum loan-to-value ratio (in hundredths)	65.00%
Amortization period of loans	25 years
Loans receivable, time period	1 year
Agricultural \| Corn and Other Grain Farming
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans	$ 366,600,000		297,400,000
Increase (decrease) in accounts and notes receivable	$ 69,200,000
Commercial and Industrial Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	7 years
Loans receivable, time period	1 year
Troubled debt restructurings balance	$ 313,000		$ 479,000
Residential Properties \| Real Estate Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum loan-to-value ratio (in hundredths)	80.00%
Amortization period of loans	25 years