Acquisitions and Dispositions	12 Months Ended
Acquisitions and Dispositions	Dec. 31, 2024
Business combinations, Asset acquisition and Disposition [Abstract]
Acquisitions and Dispositions	3. Acquisitions and Dispositions Educational Partners International In September 2024, the Company acquired a 68% ownership interest in Educational Partners International (EPI), a company that sponsors international teachers for placements in schools in the U.S. Total consideration for the Company's investment was $167.7 million. Through December 2024, the Company's investment was accounted for under the equity method, as the Company did not have control over the business due to regulatory approval that was still pending. The Company's proportionate share of earnings attributed to its investment in EPI is included in the Company's Markel Ventures segment. In January 2025, the Company received regulatory approval that resulted in the Company gaining control over EPI. The Company will consolidate EPI and perform a purchase price allocation for the acquisition in the first quarter of 2025. Valor Environmental In June 2024, the Company acquired 98% of Valor Environmental (Valor), an environmental services company providing erosion control and related services to commercial development sites and homebuilders throughout the United States. The Company has the option to acquire the remaining equity interests and the remaining equity holders have the option to sell their interests to the Company in the future. Total consideration for the transaction was $156.4 million, all of which was cash. The purchase price was preliminarily allocated to the acquired assets and liabilities of Valor based on estimated fair value at the acquisition date. The Company recognized goodwill of $107.5 million and intangible assets of $49.0 million, which included customer relationships, trade names and other intangible assets. Goodwill is primarily attributable to expected future earnings and cash flow potential of Valor, and it is not expected to be deductible for income tax purposes. Results attributable to Valor are included in the Company's Markel Ventures segment. The Company has not completed the process of determining the fair value of the assets acquired and liabilities assumed. As a result, the fair value recorded for these items is a provisional estimate and is subject to adjustment. Once completed, any adjustments resulting from the valuations may impact the individual amounts recorded for assets acquired and liabilities assumed, as well as the residual goodwill. Volante In October 2022, the Company sold its controlling interest in its Volante managing general agent companies (Volante) for total consideration of $181.9 million, of which $155.6 million was cash. This transaction resulted in a gain of $118.5 million that was included in services and other revenue. Volante underwrites and administers specialty insurance and reinsurance policies and provides delegated underwriting services to third-party providers of insurance capital. Velocity In February 2022, the Company sold the majority of its controlling interest in its Velocity managing general agent companies (Velocity) for total cash consideration of $181.3 million, which resulted in a gain of $107.3 million that was included in services and other revenues. The Company retained a minority interest in Velocity. In June 2023, the Company sold Independent Specialty Insurance Company (ISIC), a subsidiary within its program services operations, to Velocity. ISIC is a licensed insurance carrier, the value of which is attributed to its insurance licenses. This transaction resulted in a gain of $16.9 million and was included in services and other revenues.