Debt Instrument, Additional Carrying Amount

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- Definition

Debt Instrument, Face Amount, Additional Issuance

+ References

No definition available.

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- Definition

Debt Instrument, Interest Rate, Yield-To-Worst

+ References

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- Definition

Debt Instrument, Issuance Price, Percentage

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- Definition

Debt Instrument, Remaining Term

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No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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Period between issuance and maturity of debt instrument, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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DEBT - Notes Due and SBIC Debentures (Details) - USD ($)	1 Months Ended							6 Months Ended
	Mar. 31, 2026	Aug. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Jan. 31, 2024	Oct. 31, 2021	Jan. 31, 2021	Jun. 30, 2026	May 31, 2026	Apr. 08, 2026	Dec. 31, 2025	Sep. 30, 2025
Debt Instrument [Line Items]
Outstanding Balance								$ 2,541,000,000			$ 2,468,000,000
Recorded Value								2,533,853,000			2,457,594,000
March 2029 Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount					$ 350,000,000.0			$ 550,000,000.0
Debt instrument, interest rate, stated (as a percent)					6.95%			6.68%
Debt instrument, issuance price (as a percent)	102.061%				99.865%
Face amount, additional issuance	$ 200,000,000.0
Debt Instrument, interest rate, yield-to-worst	6.164%
Outstanding Balance								$ 550,000,000			350,000,000
Recorded Value								550,612,000			347,721,000
July 2026 Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount						$ 200,000,000.0	$ 300,000,000.0
Debt instrument, interest rate, stated (as a percent)							3.00%
Debt instrument, issuance price (as a percent)						101.741%	99.004%
Outstanding Balance								500,000,000			500,000,000
Recorded Value								499,978,000			499,715,000
June 2027 Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount				$ 300,000,000.0				$ 400,000,000.0
Debt instrument, interest rate, stated (as a percent)				6.50%				6.34%
Debt instrument, issuance price (as a percent)			102.134%	99.793%
Outstanding Balance								$ 400,000,000			400,000,000
Recorded Value								399,713,000			399,569,000
June 2027 Notes, Additional \| Unsecured Notes
Debt Instrument [Line Items]
Face amount			$ 100,000,000.0
Debt instrument, interest rate, stated (as a percent)			5.617%
August 2028 Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount		$ 350,000,000.0
Debt instrument, interest rate, stated (as a percent)		5.40%
Debt instrument, issuance price (as a percent)		99.989%
Outstanding Balance								350,000,000			350,000,000
Recorded Value								348,378,000			347,996,000
SBIC debentures \| Unsecured Notes
Debt Instrument [Line Items]
Face amount									$ 475,000,000.0
Outstanding Balance								$ 350,000,000			$ 350,000,000
Additional debenture capacity									$ 125,000,000.0
Debt instrument, term (in years)								10 years
Debt instrument, weighted-average annual interest rate (as a percent)								3.30%			3.30%
Debt instrument, remaining term (in years)								4 years 1 month 6 days
Recorded Value								$ 345,181,000			$ 344,593,000
SBIC debentures \| Unsecured Notes \| MSMF
Debt Instrument [Line Items]
Face amount								175,000,000.0
Recorded Value								171,200,000
Debt instrument, unamortized debt issuance costs								3,800,000
SBIC debentures \| Unsecured Notes \| MSC III
Debt Instrument [Line Items]
Face amount								175,000,000.0
Recorded Value								174,000,000.0
Debt instrument, unamortized debt issuance costs								1,000,000.0
April 2031 Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount										$ 150,000,000.0
Debt instrument, interest rate, stated (as a percent)										6.93%
Outstanding Balance								150,000,000
Recorded Value								$ 148,991,000			$ 0
December 2025 Series A Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount												$ 100,000,000.0
Debt instrument, interest rate, stated (as a percent)												7.84%
December 2025 Series B Notes \| Unsecured Notes
Debt Instrument [Line Items]
Face amount												$ 50,000,000.0
Debt instrument, interest rate, stated (as a percent)												7.53%