The amount for notes payable (written promise to pay), due to related parties.

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-Publisher FASB
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-Topic 850
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Publisher FASB
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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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-Publisher FASB
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-Topic 850
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-Section 50
-Paragraph 3
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- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

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- 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
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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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Per share or per unit amount of equity securities issued.

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RELATED PARTY TRANSACTIONS, Administrative Support Agreement, Promissory Note and Related Party Loans (Q3) (Details) - USD ($)			3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 22, 2020	Jul. 14, 2020	Sep. 30, 2021	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
Balance outstanding			$ 0			0
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
Fees payable			$ 30,000	$ 0		90,000
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	$ 1.00