STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (FY) (Parenthetical)	6 Months Ended
Dec. 31, 2020 shares
Public Shares [Member]
Stockholders' Equity
Units issued (in shares)	23,000,000

Number of new units issued during the period. Each Unit consists of one share of Class A common stock and one-half of one redeemable warrant.

No definition available.

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Namespace Prefix:	sbg_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration