Name:	hmnf_ShareBasedCompensationArrangementByShareBasedPaymentAwardTransferredFromPreviousPlan
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Represents the effect of share-based awards transferred from the previous stock-based compensation plan during the period on shares available for grant.

No definition available.

Name:	hmnf_ShareBasedCompensationArrangementByShareBasedPaymentAwardTransferredFromPreviousPlanEffectOnSharesAvailableForGrant
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Data Type:	xbrli:sharesItemType
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Represents the number of share-based awards transferred during the period to the new, upcoming payment plan.

No definition available.

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Data Type:	xbrli:sharesItemType
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Represents the effect of share-based awards transferred to the new, upcoming stock-based compensation plan during the period on shares available for grant.

No definition available.

Name:	hmnf_ShareBasedCompensationArrangementByShareBasedPaymentAwardTransferredToSubsequentPlanEffectOnSharesAvailableForGrant
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The number of share-based compensation awards that have been released during the period.

No definition available.

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Data Type:	xbrli:sharesItemType
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The number of options that have been made available for vesting during the period.

No definition available.

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Data Type:	xbrli:sharesItemType
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Data Type:	xbrli:sharesItemType
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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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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Data Type:	xbrli:sharesItemType
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:sharesItemType
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

No definition available.

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Data Type:	xbrli:sharesItemType
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Number of options outstanding, including both vested and non-vested options.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:sharesItemType
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Period Type:	instant

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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Data Type:	num:perShareItemType
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Period Type:	instant

Number of non-vested options outstanding.

No definition available.

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Data Type:	xbrli:sharesItemType
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Weighted average grant-date fair value of non-vested options outstanding.

No definition available.

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Data Type:	num:perShareItemType
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Number of options vested.

No definition available.

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Data Type:	xbrli:sharesItemType
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Weighted average grant-date fair value of options vested.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
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Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
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Data Type:	na
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Data Type:	na
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Name:	us-gaap_AwardDateAxis=hmnf_GrantedJanuary312017Member
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