Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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RELATED PARTY TRANSACTIONS, Promissory Note, Administrative Support Agreement and Related Party Loans (FY) (Details) - USD ($)			3 Months Ended	6 Months Ended	9 Months Ended
	Sep. 22, 2020	Jul. 14, 2020	Sep. 30, 2020	Dec. 31, 2020	Sep. 30, 2021
Related Party Transactions [Abstract]
Repayment of debt to related party			$ 75,000	$ 75,000	$ 0
Sponsor [Member] \| Promissory Note [Member]
Related Party Transactions [Abstract]
Repayment of debt to related party	$ 75,000
Sponsor [Member] \| Promissory Note [Member] \| Maximum [Member]
Related Party Transactions [Abstract]
Related party transaction		$ 300,000
Sponsor [Member] \| Administrative Support Agreement [Member]
Related Party Transactions [Abstract]
Related party transaction	$ 10,000
Sponsor [Member] \| Administrative Support Agreement [Member] \| Accrued Expenses [Member]
Related Party Transactions [Abstract]
Fees payable				30,000
Sponsor or an Affiliate of the Sponsor, or Certain of the Company's Officers and Directors [Member] \| Working Capital Loans [Member]
Related Party Transactions [Abstract]
Related party transaction				$ 1,500,000	$ 1,500,000
Unit price (in dollars per share)				$ 1.00	$ 1.00