Name of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Cost 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.

+ References

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Number of shares or units of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Amount of asset less liability available to pay benefit of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, aggregation of participants' individual account balances.

+ References

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- Definition

Amount of unpaid principal plus accrued but unpaid interest for loan from participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
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Employee Benefit Plan, Schedule, Asset Held for Investment (Details) - EBP 001 [Member] - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Plan Name	MARKEL GROUP INC. RETIREMENT SAVINGS PLAN
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
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Minimum [Member]
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Asset Held for Investment, Participant Loan, Interest Rate	4.25%
Maximum [Member]
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Asset Held for Investment, Participant Loan, Interest Rate	9.50%
Investment, Identifier [Axis]: Fidelity 500 Index Fund - Premium Class
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 118,203,503
EBP, Investment, Number of Shares	497,226
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Contrafund Commingled Pool - Class A
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 145,475,935
EBP, Investment, Number of Shares	2,613,653
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Equity-Income Fund - Class K
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 24,112,869
EBP, Investment, Number of Shares	288,708
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Extended Market Index Fund - Premium Class
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 26,028,151
EBP, Investment, Number of Shares	258,549
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2010 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 3,044,094
EBP, Investment, Number of Shares	228,022
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2015 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 272,371
EBP, Investment, Number of Shares	19,455
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2020 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 24,720,304
EBP, Investment, Number of Shares	1,687,393
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2025 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 8,796,471
EBP, Investment, Number of Shares	578,335
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2030 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 87,299,513
EBP, Investment, Number of Shares	5,528,785
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2035 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 15,763,417
EBP, Investment, Number of Shares	937,183
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2040 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 110,210,809
EBP, Investment, Number of Shares	6,088,995
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2045 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 13,319,461
EBP, Investment, Number of Shares	716,100
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2050 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 79,800,920
EBP, Investment, Number of Shares	4,288,067
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2055 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 10,248,311
EBP, Investment, Number of Shares	550,688
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2060 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 17,405,478
EBP, Investment, Number of Shares	935,276
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2065 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 4,322,182
EBP, Investment, Number of Shares	232,250
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom 2070 Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 218,412
EBP, Investment, Number of Shares	16,814
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Freedom Retirement Commingled Pool - Class F
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 1,480,980
EBP, Investment, Number of Shares	115,431
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Government Money Market Fund - Institutional Class
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 39,077,250
EBP, Investment, Number of Shares	39,077,250
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity International Index Fund - Premium Class
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 25,550,667
EBP, Investment, Number of Shares	420,241
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Overseas Fund - Class K
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 18,422,706
EBP, Investment, Number of Shares	257,336
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Puritan Fund - Class K6
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 31,290,364
EBP, Investment, Number of Shares	1,812,883
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity Stock Selector Small Cap Fund
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 20,776,046
EBP, Investment, Number of Shares	490,811
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: Fidelity U.S. Bond Index Fund - Institutional Class
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 31,932,329
EBP, Investment, Number of Shares	3,023,895
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Investment, Identifier [Axis]: JPMorgan Equity Income Fund - Class R6
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 7,098,149
EBP, Investment, Number of Shares	286,794
EBP, Asset Held for Investment, Party-in-Interest [true false]	false
Investment, Identifier [Axis]: John Hancock Bond Fund - Class R6
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 4,954,507
EBP, Investment, Number of Shares	361,116
EBP, Asset Held for Investment, Party-in-Interest [true false]	false
Markel Group Inc. common stock
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Excluding Plan Interest in Master Trust, Cost	$ 97,156,045	$ 95,119,536
EBP, Investment, Number of Shares	114,323	121,958
EBP, Asset Held for Investment, Party-in-Interest [true false]	true
Markel Group Inc. common stock \| Fair Value, Inputs, Level 1 [Member]
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 245,758,017	$ 210,533,330
Collective investment trusts \| Fair Value Measured at Net Asset Value [Member]
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	522,378,658	137,922,421
Mutual funds \| Fair Value, Inputs, Level 1 [Member]
EBP, Schedule of Asset Held for Investment [Line Items]
EBP, Investment, Fair Value	$ 347,446,541	$ 625,442,877