Note 8 - Subsequent Events (Details Textual)	Apr. 30, 2022 shares
Subsequent Event [Member] \| Chief Medical Officer [Member]
Stock Issuance Agreement, Number of Shares Issuable (in shares)	45,000

The number of shares issuable under stock issuance agreement.

No definition available.

Name:	mbrx_StockIssuanceAgreementNumberOfSharesIssuable
Namespace Prefix:	mbrx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant