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Related Party Transaction, Floor Rate

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Related Party Transaction, Percentage of Total Commitments

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Related Party Transaction, Transaction Amount, Shares

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Related Party Transaction, Unused Capacity, Commitment Fee Percentage

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Share Purchase Program, Percentage of Outstanding Stock Maximum

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Amount of obligations incurred and payable classified as other.

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Amount due from parties in nontrade transactions, classified as other.

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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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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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RELATED PARTY TRANSACTIONS (Details) - USD ($)	1 Months Ended					3 Months Ended	6 Months Ended
RELATED PARTY TRANSACTIONS (Details) - USD ($)	Nov. 30, 2024	Sep. 30, 2023	Mar. 31, 2022	Feb. 28, 2022	Dec. 31, 2020	Mar. 31, 2026	Jun. 30, 2026	Jan. 31, 2025
Related Party \| 2015 Deferred Compensation Plan
Related Party Transaction [Line Items]
Amounts of transaction							$ 34,500,000
Related Party \| 2015 Deferred Compensation Plan \| Rabbi Trust
Related Party Transaction [Line Items]
Amounts of transaction							$ 23,600,000
Related Party \| 2015 Deferred Compensation Plan \| Common Stock
Related Party Transaction [Line Items]
Deferred compensation (in shares)							209,678
Related Party \| 2015 Deferred Compensation Plan \| Phantom Stock Units
Related Party Transaction [Line Items]
Amounts of transaction							$ 10,900,000
External Investment Manager \| Related Party
Related Party Transaction [Line Items]
Accounts receivable from MSCC and its subsidiaries							12,300,000
External Investment Manager \| Related Party \| Operating Expenses and Amount Due From Tax Sharing Agreement
Related Party Transaction [Line Items]
Accounts receivable from MSCC and its subsidiaries							10,200,000
External Investment Manager \| Related Party \| Dividends Declared But Not Yet Paid
Related Party Transaction [Line Items]
Accounts receivable from MSCC and its subsidiaries							$ 2,100,000
MSC Income
Related Party Transaction [Line Items]
Share purchase program, percentage of outstanding stock maximum (as a percent)								3.00%
MSC Income \| Related Party
Related Party Transaction [Line Items]
Units (in shares)							2,025,220
MSC Income \| Related Party \| Unsecured Revolving Promissory Note
Related Party Transaction [Line Items]
Amounts of transaction						$ 30,000,000.0
Interest rate (as a percent)						4.50%
Interest rate, floor (as a percent)						2.00%
Unused capacity, commitment fee (as a percent)						0.25%
MSC Income \| Related Party \| Secured Revolving Promissory Note
Related Party Transaction [Line Items]
Amount of debt outstanding							$ 0
Private Loan Fund I \| Related Party \| Secured Revolving Promissory Note
Related Party Transaction [Line Items]
Amounts of transaction			$ 20,000,000.0
Interest rate (as a percent)			3.00%
Interest rate, floor (as a percent)			2.00%
Unused capacity, commitment fee (as a percent)			0.25%
Amount of debt outstanding							16,500,000
Private Loan Fund I \| Related Party \| Investment Management Agreement
Related Party Transaction [Line Items]
Amounts of transaction				$ 15,000,000.0	$ 10,000,000.0
Funded commitments							15,000,000.0
Private Loan Fund I \| Related Party \| 2015 Deferred Compensation Plan \| Rabbi Trust
Related Party Transaction [Line Items]
Amounts of transaction							2,200,000
Private Loan Fund II \| Related Party \| Secured Revolving Promissory Note
Related Party Transaction [Line Items]
Amounts of transaction	$ 10,000,000.0
Interest rate (as a percent)	3.00%
Interest rate, floor (as a percent)	2.00%
Unused capacity, commitment fee (as a percent)	0.25%
Amount of debt outstanding							0
Private Loan Fund II \| Related Party \| Investment Management Agreement
Related Party Transaction [Line Items]
Amounts of transaction		$ 15,000,000.0
Funded commitments							10,500,000
Percentage of total commitments (as a percent)		20.00%
Unfunded commitments							4,500,000
Private Loan Fund II \| Related Party \| 2015 Deferred Compensation Plan \| Rabbi Trust
Related Party Transaction [Line Items]
Amounts of transaction							$ 5,300,000