Employee Benefit Plan, Statement of Net Asset Available for Benefit (Statement) - EBP 001 [Member] - USD ($)	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
EBP, Statement of Net Asset Available for Benefit [Line Items]
EBP, Investment, Fair Value	$ 1,115,583,216	$ 973,898,628
Notes receivable from participants	8,438,547	8,327,906
Assets available for benefits	1,124,021,763	982,226,534	$ 839,322,571
Collective investment trusts \| Fair Value Measured at Net Asset Value [Member]
EBP, Statement of Net Asset Available for Benefit [Line Items]
EBP, Investment, Fair Value	522,378,658	137,922,421
Mutual funds \| Fair Value, Inputs, Level 1 [Member]
EBP, Statement of Net Asset Available for Benefit [Line Items]
EBP, Investment, Fair Value	347,446,541	625,442,877
Markel Group Inc. common stock \| Fair Value, Inputs, Level 1 [Member]
EBP, Statement of Net Asset Available for Benefit [Line Items]
EBP, Investment, Fair Value	$ 245,758,017	$ 210,533,330

Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria.

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Name:	us-gaap-ebp_EmployeeBenefitPlanInvestmentExcludingPlanInterestInMasterTrustFairValue
Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant