Name:	hmnf_FinancingReceivableDeferredLoansWithGrantedLoanModifications
Namespace Prefix:	hmnf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of deferred loans with granted loan modifications of amounts being classified downgraded and still accruing related to loan modification programs offered to financial institution customers affected by COVID-19.

No definition available.

Name:	hmnf_FinancingReceivableLoansWithPreviouslyDeferredPaymentsDowngradedClassifiedAndStillAccruing
Namespace Prefix:	hmnf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Amount of reserves for financing receivable modified as troubled debt restructuring.

No definition available.

Name:	hmnf_FinancingReceivableTroubledDebtRestructuringReserves
Namespace Prefix:	hmnf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Loan receivable for which value of collateral sufficient to repay.

No definition available.

Name:	hmnf_LoanReceivableForWhichValueOfCollateralSufficientToRepay
Namespace Prefix:	hmnf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Percentage reserves for loan losses on troubled debt restructurings.

No definition available.

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Namespace Prefix:	hmnf_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

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

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Period Type:	duration

Amount of financing receivable modified as troubled debt restructuring.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of allowance for credit losses related to recorded investment.

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-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_ImpairedFinancingReceivableRelatedAllowance
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Name:	us-gaap_LoansAndLeasesReceivableAllowance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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