Revenue - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Research development and clinical trials expenses	$ 2.1	$ 1.6

The amount of payments made to customers related to post-approval studies or existing standard-of-care protocols that are recorded as operating expenses..

No definition available.

Name:	tmdx_CustomerPaymentsRecordedAsOperatingExpenses
Namespace Prefix:	tmdx_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration