Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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

- Details

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- Details

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- Details

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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mfsf_ConsumerRecreationalVehicleFinancingReceivableMember
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Loans and Allowance (Troubled Debts Restructured Defaulted) (Details) - Consumer [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
First Mortgage [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans \| loan	1	1	1
Post-Modification Outstanding Recorded Balance \| $	$ 80	$ 48	$ 79
Second Mortgage [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans \| loan		1
Post-Modification Outstanding Recorded Balance \| $		$ 5
Boat/RVs [Member]
Financing Receivable, Modifications [Line Items]
No. of Loans \| loan	2
Post-Modification Outstanding Recorded Balance \| $	$ 299