Business and Basis of Presentation Background and Business Description - Additional Information (Details) $ / shares in Units, $ in Millions |
3 Months Ended | 6 Months Ended |
|---|---|---|
|
Jun. 30, 2026
USD ($)
level3FinancialInstruments
$ / shares
|
Jun. 30, 2026
level3FinancialInstruments
$ / shares
|
|
| Background And Basis Of Presentation [Line Items] | ||
| Entity Incorporation, Date of Incorporation | Apr. 29, 1991 | |
| Number of Admitted Carriers Owned | 5 | 5 |
| Number of Reportable Segments | 2 | |
| Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares | $ 18.50 | $ 18.50 |
| Background and Business Description | 1. BACKGROUND AND BUSINESS DESCRIPTION Business The following description provides an update of Note 1. Background and Business Description and Note 2. Basis of Presentation and Significant Accounting Policies in the Notes to the Consolidated Financial Statements included in Part II, Item 8 in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025, and should be read in conjunction with the complete descriptions provided in the Form 10-K. Capitalized terms used, but not defined herein, and in the other footnotes to the Consolidated Financial Statements included in this Quarterly Report on Form 10-Q shall have the meanings ascribed thereto in the Company’s Annual Report on Form 10-K for the year ended December 31, 2025. Octave Specialty Group, Inc. (“OSG”), headquartered in New York City and Tampa, Florida, is a financial services holding company incorporated in the state of Delaware on April 29, 1991. References to “Octave,” "OSG", the “Company,” “we,” “our,” and “us” are to OSG and its subsidiaries, as the context requires. Octave operates two principal businesses: •Insurance Distribution — Octave's specialty property and casualty ("P&C") and accident and health ("A&H") insurance underwriting and distribution business, includes Managing General Agents and Underwriters (collectively "MGAs" or "MGA/Us"); an insurance broker; and other distribution, underwriting and related businesses. On October 31, 2025, the Company completed the acquisition of ArmadaCorp Capital, LLC and its subsidiaries (collectively, "ArmadaCorp"), a leading specialty A&H MGA. Octave's insurance distribution platform operates in the following lines of business: property, niche specialty risk, accident & health, miscellaneous specialty, reinsurance, surety, marine & energy, specialty auto, Excess & Surplus ("E&S") commercial package, professional lines and Directors & Officers ("D&O") . •Specialty Property & Casualty Insurance — Octave's Specialty Property & Casualty Insurance program insurer business currently includes five carriers (collectively, “Everspan”). Everspan carriers have an A.M. Best rating of 'A-' (Excellent), which was affirmed on July 17, 2025. The Company reports these two business operations as segments; see Note 2. Segment Information for further information.
|
|
| Postemployment Benefits, Period Expense | $ | $ 13 |