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

SUBSEQUENT EVENTS (Details)

v3.24.2.u1

SUBSEQUENT EVENTS (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended			6 Months Ended		204 Months Ended
	Aug. 09, 2024	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2024
Subsequent Event [Line Items]
Increase common stock, monthly dividend, cash paid (as a percent)				4.30%
Outstanding Balance				$ 1,810,000	$ 2,211,200
SBIC Debentures
Subsequent Event [Line Items]
Proceeds from debt					0	$ 16,000
SBIC Debentures \| Unsecured Notes
Subsequent Event [Line Items]
Outstanding Balance				$ 350,000	286,200
SBIC Debentures \| Unsecured Notes \| Maximum
Subsequent Event [Line Items]
Outstanding Balance					$ 350,000
Forecast
Subsequent Event [Line Items]
Common stock, monthly dividend, per share, declared (in dollars per share)		$ 0.735	$ 0.735
Common stock, cumulative monthly dividend and supplemental dividend, per share, paid (in dollars per share)							$ 42.625
Subsequent Event
Subsequent Event [Line Items]
Common stock, supplemental cash dividend, per share, declared (in dollars per share)	$ 0.30
Subsequent Event \| Forecast \| SBIC Debentures \| Unsecured Notes
Subsequent Event [Line Items]
Proceeds from debt			$ 63,800
Subsequent Event \| Forecast \| SBIC Debentures \| Unsecured Notes \| Maximum
Subsequent Event [Line Items]
Outstanding Balance			$ 350,000				$ 350,000
Subsequent Event \| Dividends, July to September 2024
Subsequent Event [Line Items]
Common stock, monthly dividend, per share, declared (in dollars per share)	0.245
Subsequent Event \| Dividends, October to December 2024
Subsequent Event [Line Items]
Common stock, monthly dividend, per share, declared (in dollars per share)	$ 0.245

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