Percentage Of Defined Benefit Plan Contributions By Plan Participants

No definition available.

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Namespace Prefix:	mfsf_
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Period Type:	duration

- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
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Balance Type:	na
Period Type:	duration

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

+ Details

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

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Details

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- Details

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- Details

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- Details

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Employee Benefits (Narrative) (Details) - USD ($)	12 Months Ended
Employee Benefits (Narrative) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, contribution	$ 1,200,000	$ 1,200,000	$ 957,000
Supplemental retirement plan and deferred compensation arrangements
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation arrangement with individual, compensation expense	$ 790,000	$ 675,000	$ 652,000
Maximum \| Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Percentage employer matching contribution	5.00%
Up to 4% of participant contributions \| Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of participant contributions	4.00%
Percentage employer matching contribution	100.00%
4%-6% of participant contributions \| Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Percentage employer matching contribution	50.00%
4%-6% of participant contributions \| Minimum \| Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of participant contributions	4.00%
4%-6% of participant contributions \| Maximum \| Retirement savings 401(k) plan
Defined Benefit Plan Disclosure [Line Items]
Percentage of participant contributions	6.00%