Name:	hmnf_DefinedContributionPlanEmployerContributionPercentOfAnnualSalaryOfEmployee
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Data Type:	dtr-types:percentItemType
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Represents the number of additional shares purchased under an employee stock ownership plan (ESOP).

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Represents the debt structure direct original loan amount under an employee stock ownership plan (ESOP).

No definition available.

Name:	hmnf_EmployeeStockOwnershipPlanEsopDebtStructureDirectOriginalLoanAmount
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the debt structure indirect original loan amount under an employee stock ownership (ESOP).

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Represents the interest rate on a loan under an employee stock ownership plan (ESOP).

No definition available.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
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Represents the number of shares repurchased under an employee stock ownership plan (ESOP).

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Represents the maximum contribution percent by participant.

No definition available.

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

Represents the minimum age required to be eligible to participate in the entity's defined contribution plan.

No definition available.

Name:	hmnf_MinimumAgeRequiredForDefinedContributionPlanEligibility
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Data Type:	xbrli:durationItemType
Balance Type:	na
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Represents the minimum age required to be eligible to participate in employee stock option option plan.

No definition available.

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Data Type:	xbrli:durationItemType
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Represents the minimum duration of working hours required to be eligible to participate in employee stock option option plan.

No definition available.

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

Represents the number of shares as which each share of restricted stock is counted for purposes of determining total shares available for issuance under a compensation plan.

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Percentage of plan assets to benefit obligation of defined benefit plan.

No definition available.

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

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Data Type:	dtr-types:percentItemType
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Period Type:	duration

Maximum amount the employee may contribute to a defined contribution plan.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

No definition available.

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This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

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The amount of plan compensation cost recognized during the period.

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Data Type:	xbrli:monetaryItemType
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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Number of shares authorized for issuance under share-based payment arrangement.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

Gross number of share options (or share units) granted during the period.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

Number of options outstanding, including both vested and non-vested options.

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Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
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Namespace Prefix:
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