DESCRIPTION OF THE BUSINESS AND MERGER TRANSACTION - Summary of Significant Sources and Uses of Cash Related to Closing of Merger Transaction (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Business Description And Reverse Recapitalization [Abstract]
Cash at Megalith	$ 27,669
Cash from PIPE (private investment in public entity) investors	20,003
Total sources of cash	47,672
Cash paid to underwriters and other transaction costs	(3,987)
Cash paid to Customers Bank as consideration	(23,125)
Cash from recapitalization transaction (A)	20,560
Cash used to pay down BMTX debt	(8,834)
Cash received by BMTX and used to pay down debt	(6,738)
Total cash used to pay down outstanding debt (B)	(15,572)
Net cash received by BMTX from the reverse recapitalization transaction through March 31, 2021 (A+B)	4,988
90 day merger true-up, cash paid by BMTX in May 2021	(3,672)
Final cash received by BMTX from the reverse recapitalization transaction through December 31, 2021	$ 1,316