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Represents the period for modifications of financing receivables that have been modified by troubled debt restructurings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of specific reserve allocated to financing receivable modified as troubled debt restructuring.

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Amount of loans restructured under CARES Act guidelines during the period.

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Represents the threshold period after which loan is considered to be in payment default, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The effect of a change in method or methods for calculating the allowance for credit losses on the current period provision.

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

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reflects the amount of the write-down related to a troubled debt restructuring.

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Amount of unfunded portion of contractual agreement to lend funds to borrower for financing receivable modified as troubled debt restructuring.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Allowance for Credit Losses, Loans or Leases by Class Modified as Troubled Debt Restructured Loans (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($) Loan	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($) Loan	Dec. 31, 2020 USD ($) Loan
CARES Act [Abstract]
Loans restructured under the CARES act			$ 278,100,000
Formal foreclosure proceedings in process for consumer mortgage loans secured by residential real estate properties	$ 0	$ 0	0	$ 0	$ 0
Troubled Debt Restructured Loans [Abstract]
Specific reserves allocated to troubled debt restructured loans & leases	123,800	156,000	123,800	156,000	158,000
Troubled debt restructured loans	8,100,000		8,100,000
Commitments to lend additional amounts to customers with outstanding loans that are classified as troubled debt restructurings	$ 0	$ 0	$ 0	$ 0	$ 0
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan	0	1	0	6	6
Pre-Modification Outstanding Recorded Investment		$ 224,000		$ 875,000	$ 875,000
Post-Modification Outstanding Recorded Investment		$ 224,000		875,000	875,000
Increase in allowance for loan losses due to TDR					$ 120,000
TDR's charge-offs				$ 7,000
Number of loans modified as troubled debt restructurings with subsequent payment defaults \| Loan	0	0	0	0	0
Threshold period after which loan is considered to be in payment default			90 days
Stated Interest Rate Reduction [Member]
Troubled Debt Restructured Loans [Abstract]
Period of modifications				5 years	5 years
Extended Maturity [Member]
Troubled Debt Restructured Loans [Abstract]
Period of modifications				10 years
Extended Maturity [Member] \| Minimum [Member]
Troubled Debt Restructured Loans [Abstract]
Period of modifications					3 months
Extended Maturity [Member] \| Maximum [Member]
Troubled Debt Restructured Loans [Abstract]
Period of modifications					10 years
Performing [Member]
Troubled Debt Restructured Loans [Abstract]
Troubled debt restructured loans	$ 7,600,000	$ 7,900,000	$ 7,600,000	$ 7,900,000	$ 7,900,000
Residential 1st Mortgages [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		0		2	2
Pre-Modification Outstanding Recorded Investment		$ 0		$ 156,000	$ 156,000
Post-Modification Outstanding Recorded Investment		$ 0		$ 156,000	$ 156,000
Agricultural [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		0		3	3
Pre-Modification Outstanding Recorded Investment		$ 0		$ 495,000	$ 495,000
Post-Modification Outstanding Recorded Investment		$ 0		$ 495,000	$ 495,000
Commercial [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		1		1	1
Pre-Modification Outstanding Recorded Investment		$ 224,000		$ 224,000	$ 224,000
Post-Modification Outstanding Recorded Investment		$ 224,000		$ 224,000	$ 224,000