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.

No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247

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-Publisher FASB
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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Concentration Risk [Line Items]
Off-balance sheet, credit loss, liability	$ 3.9		$ 4.1
Credit loss expense, off balance sheet credit exposure	$ (0.2)	$ 2.4
Credit Concentration Risk \| Loans Concentration \| Commercial real estate
Concentration Risk [Line Items]
Concentration risk, percentage	60.00%
Credit Concentration Risk \| Loans Concentration \| Agricultural Related Loan Financing Receivable
Concentration Risk [Line Items]
Concentration risk, percentage	8.00%
Credit Concentration Risk \| Investment Securities \| State and political subdivisions \| IOWA
Concentration Risk [Line Items]
Concentration risk, percentage	20.00%
Credit Concentration Risk \| Investment Securities \| State and political subdivisions \| MINNESOTA
Concentration Risk [Line Items]
Concentration risk, percentage	14.00%