Note 9 - Subsequent Events (Details Textual) $ in Millions	1 Months Ended
Feb. 28, 2022 USD ($)
Subsequent Event [Member] \| Dermin [Member]
Payments for Termination of Commitment	$ 0.4

The amount of cash outflow for the termination of a commitment.

No definition available.

Name:	mbrx_PaymentsForTerminationOfCommitment
Namespace Prefix:	mbrx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration