Consolidated Statements Of Income (Loss) And Comprehensive Income (Loss) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2023		Mar. 31, 2022
OPERATING REVENUES
Earned premiums		$ 1,967,704		$ 1,759,770
Net investment income		159,335		92,304
Net investment gains (losses)		372,563		(358,399)
Products revenues		577,926		481,621
Services and other revenues		565,861		630,940
Total Operating Revenues		3,643,389		2,606,236
OPERATING EXPENSES
Losses and loss adjustment expenses		1,173,014		972,372
Underwriting, acquisition and insurance expenses		675,705		590,365
Products expenses		515,756		447,819
Services and other expenses		480,619	[1]	589,891
Amortization of intangible assets		44,399	[2]	46,049	[3]
Total Operating Expenses		2,889,493		2,646,496
Operating Income (Loss)		753,896		(40,260)
Interest expense		(49,438)		(49,692)
Net foreign exchange gains (losses)		(32,928)		23,004
Income (Loss) Before Income Taxes		671,530		(66,948)
Income tax (expense) benefit		(133,731)		18,136
Net Income (Loss)		537,799		(48,812)
Net income attributable to noncontrolling interests		(49,147)		(2,929)
Net Income (Loss) to Shareholders		488,652		(51,741)
Preferred stock dividends		0		0
Net Income (Loss) to Common Shareholders		488,652		(51,741)
OTHER COMPREHENSIVE INCOME (LOSS)
Net holding gains (losses) arising during the period		161,206		(521,200)
Reclassification adjustments for net losses included in net income (loss)		2,994		437
Change in net unrealized gains (losses) on available-for-sale investments, net of taxes		164,200		(520,763)
Change in discount rate for life and annuity benefits, net of taxes		(9,052)		60,693
Change in foreign currency translation adjustments, net of taxes		2,579		(1,248)
Change in net actuarial pension loss, net of taxes		18		1,132
Total Other Comprehensive Income (Loss)		157,745		(460,186)
Comprehensive Income (Loss)		695,544		(508,998)
Comprehensive income attributable to noncontrolling interests		(49,179)		(2,916)
Comprehensive Income (Loss) to Shareholders		$ 646,365		$ (511,914)
NET INCOME (LOSS) PER COMMON SHARE
Basic		$ 37.33		$ (6.50)
Diluted	[4]	$ 37.26		$ (6.50)

[1] Services and other expenses for Other for the three months ended March 31, 2023 included $44.8 million of favorable loss reserve development on the run-off of reinsurance contracts written by Markel CATCo Re Ltd., all of which was attributable to noncontrolling interests. See Note 11.

[2] Segment profit for the Markel Ventures segment includes amortization of intangible assets attributable to Markel Ventures. Amortization of intangible assets attributable to the Company's underwriting segments, included in Other, was $9.6 million for the three months ended March 31, 2023.

[3] Segment profit for the Markel Ventures segment includes amortization of intangible assets attributable to Markel Ventures. Amortization of intangible assets attributable to the Company's underwriting segments, included in Other, was $9.8 million for the three months ended March 31, 2022.

[4] The impact of 27 thousand shares from restricted stock units and restricted stock was excluded from the computation of diluted net loss per common share for the three months ended March 31, 2022 because the effect would have been anti-dilutive.