Amount of maximum borrowing capacity of related party promissory note.

No definition available.

Name:	bft_MaximumBorrowingCapacityOfRelatedPartyPromissoryNote
Namespace Prefix:	bft_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum amount of Loans that may be convertible into warrants of the post-Business Combination entity.

+ References

No definition available.

+ Details

Name:	bft_MaximumLoansConvertibleIntoWarrants
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a advances made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

+ References

No definition available.

+ Details

Name:	bft_ProceedsFromRelatedPartyAdvances
Namespace Prefix:	bft_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for the payment of a advances made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

+ References

No definition available.

+ Details

Name:	bft_RepaymentsOfRelatedPartyAdvances
Namespace Prefix:	bft_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Per unit price of warrants issued by the company.

+ References

No definition available.

+ Details

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Namespace Prefix:	bft_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_RelatedPartyTransactionLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow for the payment of a long-term borrowing made from a related party where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Payments for Advances from Affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionAxis=bft_RelatedPartyLoansMember
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Period Type:

RELATED PARTY TRANSACTIONS - Additional information (Details) - USD ($)		3 Months Ended
	Aug. 21, 2020	Sep. 30, 2020	Jul. 17, 2020
Related Party Transaction [Line Items]
Proceeds from Related Party Advances	$ 480,000	$ 480,000
Repayment of advances from related party	480,000	480,000
Repayment of promissory note - related party		500,000
Promissory Note with Related Party
Related Party Transaction [Line Items]
Maximum amounts of transaction			$ 800,000
Repayment of promissory note - related party	$ 500,000
Related Party Loans
Related Party Transaction [Line Items]
Maximum loans convertible into warrants		$ 1,500,000
Price of warrants (in dollars per share)		$ 1.50