Borrowings, Secured Credit Facility Commitment (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	May 31, 2024	Dec. 31, 2023	Sep. 26, 2022	Sep. 16, 2022	Jun. 22, 2022	May 06, 2022	Jan. 12, 2022	Jul. 02, 2021
Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	$ 200,000,000	$ 200,000,000	$ 200,000,000		$ 200,000,000		$ 125,000,000	$ 80,000,000
Borrowing capacity can be increased	$ 350,000,000
Maturity date	Jun. 30, 2028
Term of variable rate	3 months
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	us-gaap:SecuredOvernightFinancingRateSofrMember
Interest rate	2.90%
Fair value of borrowings outstanding	$ 122,500,000		176,500,000
Estimated total annualized cost of capital percentage	8.00%
Sterling National Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment									$ 55,000,000
Webster Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	$ 67,500,000		67,500,000
Dime Community Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	25,000,000		0
Blue Ridge Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	0		25,000,000
First Foundation Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	20,000,000		20,000,000
Mitsubishi HC Capital America, Inc. [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	20,000,000		20,000,000
Woodforest National Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	20,000,000		20,000,000
Forbright Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	0		17,500,000
Peapack-Gladstone Bank [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	17,000,000		15,000,000
Hanmai Bank [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	15,500,000		0
Apple Bank [Member] \| Secured Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment	$ 15,000,000		$ 15,000,000
East West Bank [Member] \| Revolving Credit Line [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment				$ 21,000,000		$ 25,000,000

Star Mountain Lower Middle-Market Capital Corp 10-K