MEMBERS' CAPITAL - Schedule of Units and DRIP Units Issued (Details) - USD ($)													12 Months Ended
	Oct. 28, 2024	Aug. 03, 2024	Jul. 26, 2024	Jul. 05, 2024	Apr. 05, 2024	Jan. 04, 2024	Sep. 29, 2023	May 12, 2023	Apr. 06, 2023	Jan. 05, 2023	Oct. 20, 2022	Jul. 25, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Units issued (in units)											1,270,258	1,156,081
Amount											$ 24,313,000	$ 21,769,000	$ 113,134,000	$ 83,165,000	$ 25,748,000
DRIP
Class of Stock [Line Items]
Units issued (in units)		1,537,393		1,491,021	1,448,077	1,442,261			1,107,144	876,757			5,918,752	4,410,240
Amount		$ 29,333,000		$ 28,552,000	$ 27,630,000	$ 27,619,000			$ 20,670,000	$ 16,413,000			$ 113,134,000	$ 83,165,000
Subscription Agreement
Class of Stock [Line Items]
Units issued (in units)	2,619,172		3,134,796				2,613,696	5,235,602					5,753,968	7,849,298
Amount	$ 50,000,000		$ 60,000,000				$ 50,000,000	$ 100,000,000					$ 110,000,000	$ 150,000,000

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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T Series Middle Market Loan Fund LLC 10-K