Performance Bonus Expense

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- Definition

Performance Bonus Expense - Executive Plan

+ References

No definition available.

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- Definition

Self funded medical plan expenses during period.

+ References

No definition available.

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- Definition

Self Funded Medical Plan, Maximum Amount Paid Per Family

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Employee Annual Salary

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- References

No definition available.

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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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- 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.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cost for defined contribution plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
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-URI https://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- 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

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- 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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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

+ References

No definition available.

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- Definition

Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

+ References

No definition available.

+ Details

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
-Name Accounting Standards Codification
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- 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.

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Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Retirement Benefits [Abstract]
Employees contribution	100.00%
Corporation matching contribution, percent	100.00%
Employee contribution, percent	5.00%
Defined Contribution Plan Disclosure [Line Items]
Performance bonus expense	$ 1,072	$ 1,063	$ 1,101
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(109)	0	(152)
Plan expenses	805	792	813
Accumulated other comprehensive income includes net unrecognized pension cost before income taxes	1,729
Corporation self-funded medical plan	100
Medical expenses	3,026	3,297	1,868
Defined Benefit Plan Disclosure [Line Items]
Performance Bonus Expense - Executive Plan	252	253	165
Other Postretirement Benefits Plan [Member]
Defined Contribution Plan Disclosure [Line Items]
Plan expenses	251	352	373
Restricted Stock \| Isabella Bank Corporation Restricted Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	147	$ 86	$ 14
Unrecognized compensation expense	$ 346
Unrecognized compensation expense, period for recognition	2 years 4 months 24 days
Minimum [Member] \| Restricted Stock \| Isabella Bank Corporation Restricted Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award as a percentage of salary	25.00%
Maximum [Member] \| Restricted Stock \| Isabella Bank Corporation Restricted Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award as a percentage of salary	40.00%
Safe Harbor 401(k) [Member]
Defined Contribution Plan Disclosure [Line Items]
Vesting percentage	100.00%
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Investment allocation in securities	50.00%
Equity Collective Trust [Member]
Defined Benefit Plan Disclosure [Line Items]
Investment allocation in securities	50.00%