DESCRIPTION OF THE BUSINESS AND MERGER TRANSACTION - Narrative (Details)	12 Months Ended
Dec. 31, 2021 revenue_source
Business Description And Reverse Recapitalization [Abstract]
Number of primary revenue sources	4

Revenue From Contracts With Customers, Number Of Primary Revenue Sources

No definition available.

Name:	bmtx_RevenueFromContractsWithCustomersNumberOfPrimaryRevenueSources
Namespace Prefix:	bmtx_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration