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

RELATED PARTY TRANSACTIONS (Details)

v3.23.1

RELATED PARTY TRANSACTIONS (Details) - Affiliated Entity - USD ($) $ in Millions		1 Months Ended			3 Months Ended
	Dec. 29, 2021	Mar. 31, 2022	Feb. 28, 2022	Dec. 31, 2020	Mar. 31, 2023	May 31, 2022
External Investment Manager
Related Party Transaction [Line Items]
Receivable					$ 9.4
MSC Income
Related Party Transaction [Line Items]
Shares acquired (in shares)					94,697	94,697
Operating Expenses and Amount Due From Tax Sharing Agreement \| External Investment Manager
Related Party Transaction [Line Items]
Receivable					$ 6.3
Dividends Declared But Not Yet Paid \| External Investment Manager
Related Party Transaction [Line Items]
Receivable					3.1
Investment Management Agreement \| Private Loan Fund
Related Party Transaction [Line Items]
Amount of transaction			$ 15.0	$ 10.0
Funded commitments					14.3
Unfunded commitments					0.7
Unsecured Revolving Promissory Note \| Private Loan Fund
Related Party Transaction [Line Items]
Amount of transaction	$ 85.0
Interest rate	5.00%
Secured Revolving Promissory Note \| Private Loan Fund
Related Party Transaction [Line Items]
Amount of transaction		$ 10.0
Interest rate		5.00%
Unused capacity, commitment fee percentage		0.25%
2015 Deferred Compensation Plan
Related Party Transaction [Line Items]
Amount of transaction					$ 17.2
2015 Deferred Compensation Plan \| Common Stock
Related Party Transaction [Line Items]
Deferred compensation (in shares)					156,122
2015 Deferred Compensation Plan \| Phantom Stock Units
Related Party Transaction [Line Items]
Amount of transaction					$ 6.2

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