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Derivative, Expected Proceeds

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Management And Service Fees, Look-Back Period Provision

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- Definition

Proceeds From Termination Of Cost Sharing Agreement

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Realized Gain (Loss) On Credit Support Agreement

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Related Party Transaction, Number Of Components

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Related Party Transaction, Term

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- Definition

Amount of expense for administrative fee from service provided, including, but not limited to, salary, rent, or overhead cost.

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- Definition

Amount of expense for incentive fee based on performance under arrangement to manage operations, including, but not limited to, investment.

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Amount of fee payable for management of operations based on performance under arrangement, including, but not limited to, investment.

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- Definition

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

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- Definition

Rate based on performance for management and service fees under arrangement to manage operations, including, but not limited to, investment.

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

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

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Amount of fee payable for management of fund or trust.

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- Definition

Amount of transactions with related party during the financial reporting period.

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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.

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AGREEMENTS AND RELATED PARTY TRANSACTIONS (Details)							3 Months Ended		9 Months Ended		12 Months Ended
AGREEMENTS AND RELATED PARTY TRANSACTIONS (Details)	Jun. 30, 2025 USD ($)	May 08, 2025 USD ($)	Feb. 25, 2022 USD ($)	Jan. 01, 2021 qtr	Dec. 23, 2020 USD ($)	Aug. 02, 2018	Sep. 30, 2025 USD ($) component	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) component	Sep. 30, 2024 USD ($)	Dec. 31, 2018	Dec. 31, 2024 USD ($)
Related Party Transaction [Line Items]
Look-back period provision \| qtr				12
Base management fee							$ 8,415,000	$ 8,046,000	$ 24,626,000	$ 24,515,000
Base management fees payable							8,415,000		8,415,000			$ 7,888,000
Incentive management fees							5,634,000	6,597,000	24,489,000	15,886,000
Incentive management fees payable							5,634,000		5,634,000			7,871,000
Administrative fees expenses							400,000	400,000	1,100,000	1,400,000
Administrative fees payable							351,000		351,000			$ 540,000
Proceeds from termination of CSA									23,000,000	0
Gain on credit support agreement							$ 0	0	9,400,000	0
Barings LLC \| MVC Credit Support Agreement
Related Party Transaction [Line Items]
Expected proceeds from termination		$ 23,000,000
Proceeds from termination of CSA	$ 23,000,000
Gain on credit support agreement									$ 9,400,000
Original Advisory Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Base management fee, percent						1.375%
Incentive fee, percent			2.00%
Amended and Restated Advisory Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Base management fee, percent				1.25%
New Barings BDC Advisory Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent			2.0625%
Original Advisory Agreement - Annualized Incentive Fee Rate \| Affiliated Entity
Related Party Transaction [Line Items]
Base management fee, percent			8.00%
New Barings BDC Advisory Agreement - Annualized Incentive Fee Rate \| Affiliated Entity
Related Party Transaction [Line Items]
Base management fee, percent			8.25%
Investment Advisory Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Base management fee, percent									1.25%
Investment Management Agreement \| Related Party
Related Party Transaction [Line Items]
Number of components \| component							2		2
Investment Management Agreement - Incentive Rate, Quarterly Hurdle Rate \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				2.0625%
Investment Management Agreement - Incentive Rate, Annualized Hurdle Rate \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				8.25%
Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				100.00%
Investment Management Agreement - Incentive Rate, Quarterly Catch-Up Threshold \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				2.57812%
Investment Management Agreement - Incentive Rate, Annual Catch-Up Threshold \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				10.3125%
Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				20.00%
Pre-Incentive Fee Net Investment Income For Trailing Twelve Quarters Exceeds Catch-Up Amount \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				20.00%
Investment Management Agreement - Incentive Rate, Cumulative Pre-Incentive Fee Net Return \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent				20.00%
Investment Management Agreement - Incentive Rate, Realized Capital Gains \| Affiliated Entity
Related Party Transaction [Line Items]
Incentive fee, percent											20.00%
Investment Management Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income
Related Party Transaction [Line Items]
Incentive management fees							$ 5,600,000	6,600,000	$ 24,500,000	15,900,000
Investment Management Agreement - Incentive Rate, Capital Gain Fee
Related Party Transaction [Line Items]
Incentive management fees							$ 0	$ 0	$ 0	$ 0
MVC Credit Support Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction amount (up to)					$ 23,000,000
Related party transaction, term					10 years
MVC Credit Support Agreement - Covered Credit Losses Minimum \| Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction amount (up to)					$ 0.00
Sierra Credit Support Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction amount (up to)			$ 100,000,000
Related party transaction, term			10 years
Sierra Credit Support Agreement Covered Credit Losses Minimum \| Affiliated Entity
Related Party Transaction [Line Items]
Related party transaction amount (up to)			$ 0.00