Note 17 - Regulatory Capital (Details Textual)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2016
Capital Conservation Buffer		0.625%
Scenario, Forecast [Member]
Capital Conservation Buffer	2.50%

Percentage of common equity tier 1 capital above its minimum risk-based capital requirements in order to avoid limitations on capital distributions, including dividend payments and certain discretionary bonus payments to executive officers.

No definition available.

Name:	hmnf_CapitalConservationBuffer
Namespace Prefix:	hmnf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration