Note 11 - Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Jan. 01, 2019
Operating Lease, Right-of-Use Asset	$ 4,400
Operating Lease, Liability, Total	$ 4,387
Minimum [Member]
Lessee, Operating Leases, Remaining Lease Term	1 year
Lessee, Operating Lease, Renewal Term	3 years
Maximum [Member]
Lessee, Operating Leases, Remaining Lease Term	6 years
Lessee, Operating Lease, Renewal Term	10 years
Accounting Standards Update 2016-02 [Member] \| Other Assets [Member]
Operating Lease, Right-of-Use Asset		$ 4,500
Accounting Standards Update 2016-02 [Member] \| Other Liabilities [Member]
Operating Lease, Liability, Total		$ 4,500

Represents the remaining lease term under operating leases.

No definition available.

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Namespace Prefix:	hmnf_
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Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

+ Details

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

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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Period Type:	instant

- Details

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- Details

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