The amount of transition fee to the advisory.

No definition available.

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- Definition

The advisory transition fee, as a percentage on consideration paid for business combination.

+ References

No definition available.

+ Details

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- Definition

Option to purchase maximum number of additional units.

+ References

No definition available.

+ Details

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- Definition

The over allotment period within which the underwriter has to exercise the over allotment option.

+ References

No definition available.

+ Details

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- Definition

Amount of underwriter fee paid.

+ References

No definition available.

+ Details

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- Definition

The amount of reimbursement of expenses by underwriters.

+ References

No definition available.

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- Definition

The amount of underwriting discount.

+ References

No definition available.

+ Details

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- Definition

The percentage of gross proceeds of the offering, entitled as underwriting discount.

+ References

No definition available.

+ Details

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- Definition

The percentage of over-allotment proceeds, entitled as underwriting fee.

+ References

No definition available.

+ Details

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- Definition

Represents the number of units issued during the period.

+ References

No definition available.

+ Details

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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
Period Type:	duration

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

- Definition

The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

+ 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
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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COMMITMENTS AND CONTINGENCIES (Details) - USD ($)				3 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) - USD ($)	Jan. 22, 2026	Jan. 20, 2026	Sep. 30, 2025	Mar. 31, 2026	Jan. 23, 2026	Jan. 15, 2026
COMMITMENTS AND CONTINGENCIES
Price per unit issued		$ 10			$ 10
Total proceeds				$ 2,750,000
Underwriting discount, amount				$ 1,000,000
Advisory transition fee, percent			1.00%
Minimum
COMMITMENTS AND CONTINGENCIES
Advisory transition fee, amount			$ 1,000,000
Maximum
COMMITMENTS AND CONTINGENCIES
Advisory transition fee, amount			$ 3,000,000
Over-Allotment Option
COMMITMENTS AND CONTINGENCIES
Underwriter purchase option term	45 days			45 days
Number of units issued	2,750,000			2,750,000
Units issued during period, shares, issued				227,500
Price per unit issued	$ 10	$ 10
Underwriting discount, percent of gross proceeds				1.00%
Underwriting fee, percent				0.50%
Option to purchase maximum number of additional units	3,000,000	3,000,000
Gross proceeds from issuance of units	$ 27,500,000	$ 27,500,000
Underwriter fee				$ 1,137,500
Over-Allotment Option \| Maximum
COMMITMENTS AND CONTINGENCIES
Underwriting discount, amount				1,000,000
Maximum expense reimbursement				$ 125,000
$15 Private Warrants
COMMITMENTS AND CONTINGENCIES
Exercise price per warrant		$ 15				$ 15