| Cover | Jul. 13, 2024 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jul. 13, 2024 |
| Entity File Number | 814-01366 |
| Entity Registrant Name | SL Investment Corp. |
| Entity Central Index Key | 0001825590 |
| Entity Tax Identification Number | 85-3472615 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 1585 Broadway |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10036 |
| City Area Code | 212 |
| Local Phone Number | 761-4000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | None |
| Entity Emerging Growth Company | true |
| Elected Not To Use the Extended Transition Period | true |
