Aggregate base rent.

No definition available.

Name:	mbx_AggregateBaseRent
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Future remaining clinical and regulatory milestone payments.

+ References

No definition available.

+ Details

Name:	mbx_FutureRemainingClinicalAndRegulatoryMilestonePayments
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Lease agreement commencement date.

+ References

No definition available.

+ Details

Name:	mbx_LeaseAgreementCommencementDate
Namespace Prefix:	mbx_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Lease commencement date.

+ References

No definition available.

+ Details

Name:	mbx_LeaseCommencementDate
Namespace Prefix:	mbx_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	instant

- Definition

License fees paid.

+ References

No definition available.

+ Details

Name:	mbx_LicenseFeesPaid
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum additional clinical and regulatory milestones amount.

+ References

No definition available.

+ Details

Name:	mbx_MaximumAdditionalClinicalAndRegulatoryMilestonesAmount
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Milestone payable.

+ References

No definition available.

+ Details

Name:	mbx_MilestonePayable
Namespace Prefix:	mbx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of Months Option to Extend

+ References

No definition available.

+ Details

Name:	mbx_NumberOfMonthsOptionToExtend
Namespace Prefix:	mbx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of years option to extend.

+ References

No definition available.

+ Details

Name:	mbx_NumberOfYearsOptionToExtend
Namespace Prefix:	mbx_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in obligation for operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-SubTopic 20
-Topic 842
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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Namespace Prefix:	us-gaap_
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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

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

- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

+ Details

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

- Definition

Description of terms and conditions of option to terminate lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

+ Details

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

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

Name:	us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-4

+ Details

Name:	us-gaap_OperatingLeaseExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 5
-Subparagraph (c)
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-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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- Details

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Period Type:

- Details

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Commitments and Contingencies - Additional Information (Details) - USD ($)		1 Months Ended			3 Months Ended		6 Months Ended		12 Months Ended
	May 09, 2025	Mar. 31, 2026	Feb. 28, 2026	Apr. 30, 2022	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Jan. 31, 2024
Lessee, Lease, Description [Line Items]
Increase in lease liability							$ 2,745,000	$ 479,000
Operating lease rent expense					$ 200,000	$ 100,000	300,000	100,000
Cash paid for amounts included in measurement of operating lease liability					100,000	100,000	100,000	100,000
Right-of use assets					2,759,000		2,759,000		$ 487,000
The License Agreement \| IURTC
Lessee, Lease, Description [Line Items]
Additional clinical and regulatory milestones										$ 9,000,000
Future remaining clinical and regulatory milestone payments										$ 9,300,000
License fees paid						$ 0		$ 0
Milestone payable		$ 100,000							1,000,000
Burlington MA
Lessee, Lease, Description [Line Items]
Lease term (in months)			4 years
Lessee, Operating Lease, Existence of Option to Extend [true false]			true
Lease option to extend			one-time option to extend the lease term for a period of three years
Number of additional years option to extend			3 years
Lease agreement commencement date			Apr. 14, 2026
Lease term			4 years
Aggregate base rent			$ 3,400,000
Burlington MA \| The License Agreement
Lessee, Lease, Description [Line Items]
Lease liability					2,800,000		2,800,000
Right-of use assets					2,400,000		$ 2,400,000
The Carmel Lease
Lessee, Lease, Description [Line Items]
Lease term (in months)				39 months
Termination of lease	December 31, 2028						December 31, 2025
Lessee, Operating Lease, Existence of Option to Extend [true false]	true			true
Lease option to extend	option to extend for 36 additional						option to extend for 36 additional
Number of additional months option to extend	36 months
Increase in lease liability									$ 600,000
Lease liability					$ 3,341,000		$ 3,341,000
Lease term				39 months
Laboratory Space
Lessee, Lease, Description [Line Items]
Termination of lease							December 2025
Lease commencement date					2024-12		2024-12