Main Street Capital Corporation Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Cover
Financial Statements
Notes to Financial Statements
Accounting Policies
- SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)
Notes Tables
Notes Details

DEBT - Notes??Due (Details)

v3.23.1

DEBT - Notes Due (Details) - Unsecured Notes	1 Months Ended
DEBT - Notes Due (Details) - Unsecured Notes	Oct. 31, 2021 USD ($)	Jan. 31, 2021 USD ($)	Jul. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Apr. 30, 2019 USD ($)	Nov. 30, 2017 USD ($)	Mar. 31, 2023 USD ($)	Feb. 28, 2023 USD ($)	Dec. 31, 2022 USD ($) agency
December 2022 Notes
Debt Instrument [Line Items]
Debt instrument, face amount						$ 185,000,000
Debt instrument, interest rate, stated percentage						4.50%
Debt instrument, issuance price, percentage						99.16%
May 2024 Notes
Debt Instrument [Line Items]
Debt instrument, face amount			$ 125,000,000	$ 75,000,000	$ 250,000,000		$ 450,000,000		$ 450,000,000
Debt instrument, interest rate, stated percentage					5.20%
Debt instrument, issuance price, percentage			102.70%	105.00%	99.125%
July 2026 Notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 200,000,000	$ 300,000,000					500,000,000		500,000,000
Debt instrument, interest rate, stated percentage		3.00%
Debt instrument, issuance price, percentage	101.741%	99.004%
December 2025 Notes
Debt Instrument [Line Items]
Debt instrument, face amount							$ 150,000,000		$ 150,000,000
Debt instrument, credit rating, below investment grade event, percentage of agencies									67.00%
Debt instrument, secured debt ratio event									0.35
December 2025 Notes \| Minimum
Debt Instrument [Line Items]
Debt instrument, credit rating, below investment grade rating, number of agencies \| agency									1
December 2025 Notes \| Maximum
Debt Instrument [Line Items]
Debt instrument, credit rating, below investment grade rating, number of agencies \| agency									2
December 2025 Series A Notes
Debt Instrument [Line Items]
Debt instrument, face amount									$ 100,000,000
Debt instrument, interest rate, stated percentage									7.84%
December 2025 Series B Notes
Debt Instrument [Line Items]
Debt instrument, face amount								$ 50,000,000
Debt instrument, interest rate, stated percentage								7.53%

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