No definition available.

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- Definition

Period of time after the completion of initial Business Combination in which initial shareholders are not permitted to transfer, assign or sell any of their held Founder Shares, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Period after the initial Business Combination for the common stock price to exceed the threshold price per share, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Ratio applied to the conversion of stock, for example but not limited to, one share converted to two or two shares converted to one.

+ References

No definition available.

+ Details

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- Definition

Threshold period of specified consecutive trading days that common stock price must exceed threshold price for specified number of trading days, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Threshold number of specified trading days that common stock price must exceed threshold price within a specified consecutive trading period, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	fiac_
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Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-14

+ Details

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Balance Type:	debit
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
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Related Party Transactions, Founder Shares (Q3) (Details)			9 Months Ended	10 Months Ended	12 Months Ended
	Sep. 12, 2023 $ / shares	Mar. 15, 2021 USD ($) shares	Sep. 30, 2023 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) $ / shares
Founder Shares [Abstract]
Proceeds from issuance of ordinary share \| $				$ 25,000	$ 0
Stock conversion basis at time of business combination			1		1
Founder Shares [Member] \| Class A Common Stock [Member] \| Minimum [Member]
Founder Shares [Abstract]
Period after initial Business Combination			150 days		150 days
Sponsor [Member]
Founder Shares [Abstract]
Stock conversion basis at time of business combination	1
Holding period for transfer, assignment or sale of founder shares			360 days
Threshold trading days			20 days
Threshold consecutive trading days			30 days
Period after initial Business Combination			150 days
Sponsor [Member] \| Minimum [Member]
Founder Shares [Abstract]
Share price (in dollars per share) \| $ / shares	$ 12
Sponsor [Member] \| Founder Shares [Member] \| Class A Common Stock [Member]
Founder Shares [Abstract]
Threshold trading days			20 days		20 days
Threshold consecutive trading days			30 days		30 days
Sponsor [Member] \| Founder Shares [Member] \| Class A Common Stock [Member] \| Minimum [Member]
Founder Shares [Abstract]
Share price (in dollars per share) \| $ / shares			$ 12		$ 12
Sponsor [Member] \| Founder Shares [Member] \| Class B Common Stock [Member]
Founder Shares [Abstract]
Proceeds from issuance of ordinary share \| $		$ 25,000	$ 25,000
Shares issued (in shares) \| shares		7,187,500	5,750,000
Stock conversion basis at time of business combination			1		1
Holding period for transfer, assignment or sale of founder shares			1 year		1 year