Income Taxes - Summary of Tax Character of Shareholder Distributions (Parenthetical) (Details)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Percentage of ordinary income qualified as interest related dividend exempt from US withholding tax applicable to non-US shareholder	75.72%	78.26%	88.32%

Percentage of ordinary income qualified as interest related dividend exempt from domestic withholding tax applicable to foreign shareholder.

No definition available.

Name:	ck0001925309_PercentageOfOrdinaryIncomeQualifiedAsInterestRelatedDividendExemptFromDomesticWithholdingTaxApplicableToForeignShareholder
Namespace Prefix:	ck0001925309_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration