N-2 - $ / shares |
3 Months Ended | |||
|---|---|---|---|---|
Mar. 31, 2026 |
Dec. 31, 2025 |
Mar. 31, 2025 |
Dec. 31, 2024 |
|
| Cover [Abstract] | ||||
| Entity Central Index Key | 0001655050 | |||
| Amendment Flag | false | |||
| Securities Act File Number | 814-01175 | |||
| Document Type | 10-Q | |||
| Entity Registrant Name | BAIN CAPITAL SPECIALTY FINANCE, INC. | |||
| Entity Address, Address Line One | 200 Clarendon Street | |||
| Entity Address, Address Line Two | 37th Floor | |||
| Entity Address, City or Town | Boston | |||
| Entity Address, State or Province | MA | |||
| Entity Address, Postal Zip Code | 02116 | |||
| City Area Code | 617 | |||
| Local Phone Number | 516‑2000 | |||
| Entity Emerging Growth Company | false | |||
| General Description of Registrant [Abstract] | ||||
| Share Price | $ 12.4 | $ 16.6 | ||
| NAV Per Share | $ 16.86 | $ 17.23 | $ 17.64 | $ 17.65 |
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'. No definition available.
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- Definition Address Line 1 such as Attn, Building Name, Street Name No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate if registrant meets the emerging growth company criteria. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen. No definition available.
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Local phone number for entity. No definition available.
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- Definition Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Price of a single share of a number of saleable stocks of a company. No definition available.
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