DESCRIPTION OF PLAN (Details) - EBP 001 - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
EBP, Description of Plan [Line Items]
Automatic deferral rate	5.00%
Employer contribution, matching percentage	100.00%
Employer contribution, participant compensation matched, percentage	3.00%
Employer contribution, matching percentage after initial percent of eligible compensation	50.00%
Employer contribution, participant compensation matched, percentage after initial percent of eligible compensation	2.00%
Participant maximum contribution	80.00%
Administrative expense allocation, minimum balance for allocation	$ 2,000
Employer contribution vesting percentage	100.00%
Forfeited nonvested account	$ 1,309	$ 1,141
Note receivable from participant, minimum borrowing amount	1,000
Note receivable from participant, maximum borrowing amount	$ 50,000
Note receivable from participant maximum borrowing, to total account, percentage	50.00%
Note receivable from participant, general loan, maximum borrowing term	5 years
Termination of service with vested benefits (less than)	$ 1,000
Maximum common stock ownership by participant	5.00%
Maximum common stock ownership, purchase limit	10.00%
Minimum
EBP, Description of Plan [Line Items]
Participant loan, interest rate	4.25%
Maximum
EBP, Description of Plan [Line Items]
Participant loan, interest rate	9.50%

EBP, Administrative Expense Allocation, Threshold, Minimum Balance For Allocation

No definition available.

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Balance Type:	debit
Period Type:	instant

- Definition

EBP, Employer Contribution, Matching Percentage After Initial Percent Of Eligible Compensation

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Contribution, Participant Compensation Matched, Percentage After Initial Percent Of Eligible Compensation

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Employer Contribution Vesting Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Involuntary Cash-Out Limit

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Ownership Percentage, Common Stock, Purchase Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

EBP, Participant Ownership Percentage, Common Stock, Threshold

+ References

No definition available.

+ Details

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Namespace Prefix:	mchb_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanEmployerContributionMatchingPercentage
Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of plan asset, in forfeited nonvested account, no longer allocated to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

Name:	us-gaap-ebp_EmployeeBenefitPlanNoteReceivableFromParticipantAccountMaximumBorrowingAmount
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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- Details

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