Price per warrants or rights issued during the period.

No definition available.

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- Definition

Number of warrants or rights issued.

+ References

No definition available.

+ Details

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- Definition

Represents the number of warrants issued.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Represents the number of units issued during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	fgii_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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

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

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
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Period Type:	instant

- Details

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- Details

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- Details

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Data Type:	na
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- Details

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Data Type:	na
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PRIVATE PLACEMENT (Details) - USD ($)		3 Months Ended
PRIVATE PLACEMENT (Details) - USD ($)	Jan. 20, 2026	Mar. 31, 2026	Jan. 23, 2026
PRIVATE PLACEMENT
Price per unit issued	$ 10		$ 10
Aggregate purchase price		$ 100,000
Private Warrants \| Class A ordinary share
PRIVATE PLACEMENT
Exercise price per warrant	$ 11.5
Number of securities called by each warrant	1
Private Warrants \| Sponsor \| Class A ordinary share
PRIVATE PLACEMENT
Exercise price per warrant	$ 15
Aggregate purchase price	$ 100,000
Number of securities called by each warrant	1
Public Warrant
PRIVATE PLACEMENT
Exercise price per warrant	$ 11.5
Number of securities called by each warrant	1
Public Warrant \| Class A ordinary share
PRIVATE PLACEMENT
Exercise price per warrant	$ 11.5
Number of securities called by each warrant	1
Private placement
PRIVATE PLACEMENT
Number of units issued		275,000
Price per unit issued	$ 0.1
Gross proceeds from issuance of units	$ 2,483,000
Number of warrants issued		1,000,000
Exercise price per warrant		$ 15
Private placement \| Sponsor
PRIVATE PLACEMENT
Number of units issued	275,000
Price per unit issued	$ 10
Private placement \| Sponsor \| Class A ordinary share
PRIVATE PLACEMENT
Exercise price per warrant	$ 15
Private placement \| Private Unit Warrant \| Sponsor
PRIVATE PLACEMENT
Number of units issued	275,000
Price per unit issued	$ 10
Gross proceeds from issuance of units	$ 2,750,000
Private placement \| Private Warrants \| Sponsor
PRIVATE PLACEMENT
Number of warrants issued	1,000,000
Number of warrants issued	1,000,000
Exercise price per warrant	$ 15
Price per warrant issued	0.1
Private placement \| Private Warrants \| Sponsor \| Class A ordinary share
PRIVATE PLACEMENT
Exercise price per warrant	$ 15
Aggregate purchase price	$ 100,000
Number of securities called by each warrant	1