Subsequent Events (Details) - Subsequent Event [Member] - Class B Common Stock [Member]	Aug. 05, 2019 shares
Class of Stock Disclosures [Abstract]
Number of shares forfeited (in shares)	218,750
Common Stock, shares outstanding (in shares)	6,250,000

Number of shares of common stock subject to forfeiture that were forfeited due to the over-allotment option that was not exercised by the underwriters.

No definition available.

Name:	smmc_CommonStockSharesSubjectToForfeitureForfeited
Namespace Prefix:	smmc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant