Amount of fee payable upon closing of initial business combination.

No definition available.

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- Definition

The amount of capital markets advisory service fee payable.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The amount of cash underwriting fee paid.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of deferred underwriting discount payable.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the amount of deferred underwriting fee incurred.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Percent of deferred underwriting discount to underwriters on gross proceeds.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percent of cash underwriting discount to underwriters on gross proceeds.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

The amount of reimbursement payable to the counter party at the completion or termination of the transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	sbxd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents underwriters over allotment option period.

+ References

No definition available.

+ Details

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

- Definition

Number of units reserved for future issuance.

+ References

No definition available.

+ Details

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

- 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

- Details

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- Details

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Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=sbxd_SilverboxSecuritiesLlcMember
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Balance Type:
Period Type:

- Details

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Period Type:

- Details

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COMMITMENTS AND CONTINGENCIES - Underwriting Agreement (Details) - USD ($)						12 Months Ended
	Aug. 28, 2025	Aug. 27, 2025	Aug. 19, 2025	Aug. 06, 2025	Aug. 19, 2024	Dec. 31, 2025
COMMITMENTS AND CONTINGENCIES
Capital markets advisory services fee payable				$ 10,300,000
Reimbursement payable				75,000
Deferred underwriting fee	$ 6,030,000.00	$ 10,300,000	$ 10,300,000
Over-Allotment option
COMMITMENTS AND CONTINGENCIES
Underwriters option period						45 days
Number of units intended to be issued						3,000,000
Initial Public Offering
COMMITMENTS AND CONTINGENCIES
Cash underwriting discount paid					$ 1,700,000
Cash underwriting discount (in percent)					0.85%
Deferred underwriting discount (in percent)					5.15%
Deferred underwriting discount					$ 10,300,000
Deferred underwriting fee	$ 6,030,000.00			$ 10,300,000
Initial Public Offering \| SilverBox Securities \| Financial advisory services \| Related party
COMMITMENTS AND CONTINGENCIES
Cash underwriting discount paid					170,000
Amount of fee payable upon closing of initial business combination					$ 2,030,000