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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 deferred as of balance sheet date.

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No definition available.

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No definition available.

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

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

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Allowance for Credit Losses, Loans by Class Modified as Troubled Debt Restructured Loans (Details)	9 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) Loan	Dec. 31, 2019 USD ($) Loan
CARES Act [Abstract]
Loans restructured under the CARES act	$ 277,600,000
Loans remaining in deferral status	3,700,000	$ 3,700,000
Troubled Debt Restructured Loans [Abstract]
Specific reserves allocated to troubled debt restructured loans & leases	158,000	158,000	$ 612,000
Commitments to lend additional amounts to customers with outstanding loans that are classified as troubled debt restructurings	0	$ 0	$ 0
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		6	2
Pre-Modification Outstanding Recorded Investment		$ 875,000	$ 396,000
Post-Modification Recorded Outstanding Investment		875,000	396,000
Increase in allowance for loan losses due to TDR		120,000	101,000
TDR's charge-offs		$ 0	$ 0
Number of loans modified as troubled debt restructurings with subsequent payment defaults \| Loan		0	0
Stated Interest Rate Reduction [Member]
Troubled Debt Restructured Loans [Abstract]
Period of modifications		5 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	$ 7,900,000	$ 7,900,000	$ 12,100,000
Residential 1st Mortgages [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		2
Pre-Modification Outstanding Recorded Investment		$ 156,000
Post-Modification Recorded Outstanding Investment		$ 156,000
Agricultural [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		3	1
Pre-Modification Outstanding Recorded Investment		$ 495,000	$ 201,000
Post-Modification Recorded Outstanding Investment		$ 495,000	$ 201,000
Commercial [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan		1
Pre-Modification Outstanding Recorded Investment		$ 224,000
Post-Modification Recorded Outstanding Investment		$ 224,000
Consumer & Other [Member]
Loans by class modified as troubled debt restructured loans [Abstract]
Number of Loans \| Loan			1
Pre-Modification Outstanding Recorded Investment			$ 195,000
Post-Modification Recorded Outstanding Investment			$ 195,000