Accrued reserve for additional incentive compensation

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- Definition

management fee waving description.

+ References

No definition available.

+ Details

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- Definition

Percentage of increase in cumulative total return of incentive compensation.

+ References

No definition available.

+ Details

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- Definition

Percentage of management fee on assets.

+ References

No definition available.

+ Details

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- Definition

Percentage of management fee on net asset value.

+ References

No definition available.

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- Definition

Percentage of net asset value.

+ References

No definition available.

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- Definition

Percentage of reduction of cumulative return hurdle.

+ References

No definition available.

+ Details

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- Definition

Percentage of reduction of incentive compensation on net investment income and net unrealized losses.

+ References

No definition available.

+ Details

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- Definition

Percentage rate of net realized gains on income fee reduction

+ References

No definition available.

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- Definition

Amount of fee contractually waived by investment company.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
-Subparagraph (SX 210.6-07(2)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

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- Definition

Base rate for management and service fees under arrangement to manage operations, including, but not limited to, investment.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1

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- Definition

Amount of expense for investment management fee, including, but not limited to, expense in connection with research, selection, supervision, and custody of investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479168/946-830-55-10

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-Paragraph 1
-SubTopic 10
-Topic 850
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483326/850-10-50-1

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- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

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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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Management Fees, Incentive Fees and Other Expenses - Additional Information (Details) - USD ($)					3 Months Ended		9 Months Ended		12 Months Ended	89 Months Ended	92 Months Ended
	Feb. 24, 2025	Mar. 18, 2024	Mar. 17, 2024	Feb. 08, 2019	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Jun. 30, 2026	Sep. 30, 2026
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Percentage of management fee on assets										200.00%	200.00%
Percentage of management fee on net asset value											1.50%
Base management fee rate				150.00%
Percentage of net asset value				200.00%
Mangement fee waving description	On February 24, 2025, the Advisor voluntarily agreed to waive one third of its management fee for each of the first three quarters of 2025, starting on January 1, 2025 and ending on September 30, 2025.
Advisor waived									$ (7,300,000)
Price per share					$ 4		$ 4				$ 4
Reduction in management fees					$ (3,018,683)	$ (5,544,927)	$ (11,910,234)	$ (16,489,889)
Cumulative total return							7.00%
Accrued reserve for additional incentive compensation					$ 0		$ 0		$ 0		$ 0
Maximum
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Percentage of management fee on net asset value											1.50%
Percentage of reduction of incentive compensation on net investment income and net unrealized losses											20.00%
Percentage of reduction of cumulative return hurdle											8.00%
Percentage rate of net realized gains on income fee reduction				20.00%
Minimum
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Percentage of management fee on net asset value											1.00%
Percentage of reduction of incentive compensation on net investment income and net unrealized losses											17.50%
Percentage of reduction of cumulative return hurdle											7.00%
Percentage rate of net realized gains on income fee reduction				17.50%
BlackRock Capital Investment Corporation
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Base management fee rate		100.00%	150.00%	100.00%
Percentage of net asset value		200.00%	200.00%
Reduction in management fees							$ (1,200,000)
BlackRock Capital Investment Corporation \| Maximum
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Base management fee rate		150.00%		150.00%
Price per share		$ 0.32		$ 0.32
BlackRock Capital Investment Corporation \| Minimum
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Base management fee rate		125.00%		125.00%
Percentage of net asset value		200.00%		200.00%