Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Jan. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined contribution plan, contribution amount		$ 0.0	$ 0.0	$ 0.0
Recorded unconditional purchase commitment, minimum quantity required	$ 9.5
Recorded unconditional purchase commitment, maturity year and month	2029-12
Remaining purchase commitment		$ 7.0

Maturity year and month of recorded unconditional purchase commitment.

No definition available.

Name:	tmdx_RecordedUnconditionalPurchaseCommitmentMaturityYearAndMonth
Namespace Prefix:	tmdx_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount remaining on an unconditional purchase commitment.

+ References

No definition available.

+ Details

Name:	tmdx_UnconditionalPurchaseObligationRemainingAmount
Namespace Prefix:	tmdx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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

- Definition

Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 6
-URI https://asc.fasb.org/extlink&oid=123406679&loc=d3e25383-109308

+ Details

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