CONDENSED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical)	3 Months Ended
Sep. 30, 2020 shares
Over-allotment
Maximum shares subject to forfeiture	699,164
Class A common stock
Sale of units (in shares)	146,703,345
Sale of warrants (in shares)	20,893,780
Class B common stock \| Over-allotment
Maximum shares subject to forfeiture	699,164

Represents the maximum number of common stock shares subject to forfeiture.

No definition available.

Name:	bft_MaximumCommonStockSharesSubjectToForfeiture
Namespace Prefix:	bft_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant