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v3.25.1

Segment Reporting Disclosures (Company's Segment Disclosures) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Segment Reporting Information [Line Items] |  |
Earned premiums | $ 2,089,374 | $ 2,127,627
Net investment income | 237,095 | 218,269
Net investment gains (losses) | (149,071) | 902,281
Products revenues | 561,124 | 600,840
Services and other revenues | 660,583 | 617,638
Operating revenues | 3,399,105 | 4,466,655
Attritional Current Year Claims and Claims Adjustment Expense | (1,338,709) | (1,364,770)
Catastrophe Current Year Claims and Claims Adjustment Expense | (66,063) | 0
Losses and loss adjustment expenses, prior accident year | 150,107 | 77,023
Amortization of policy acquisition costs | (417,009) | (434,587)
Other underwriting expenses | (330,429) | (304,165)
Products expenses | (499,908) | (523,247)
Services and other expenses | (567,628) | (536,838)
Amortization of acquired intangible assets | (46,942) | (44,285)
Operating Income | 282,524 | 1,335,786
Interest expense | (52,140) | (45,548)
Net foreign exchange gains (losses) | (72,633) | 51,500
Income before income taxes | 157,751 | 1,341,738
Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | 1,817,851 | 1,874,461
Net investment income | 0 | 0
Net investment gains (losses) | 0 | 0
Products revenues | 0 | 0
Services and other revenues | 0 | 0
Operating revenues | 1,817,851 | 1,874,461
Attritional Current Year Claims and Claims Adjustment Expense | (1,156,956) | (1,201,555)
Catastrophe Current Year Claims and Claims Adjustment Expense | (64,113) | 0
Losses and loss adjustment expenses, prior accident year | 126,452 | 97,181
Amortization of policy acquisition costs | (354,507) | (373,778)
Other underwriting expenses | (315,511) | (288,999)
Products expenses | 0 | 0
Services and other expenses | 0 | 0
Operating Income | 53,216 | 107,310
Reinsurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | 271,549 | 253,339
Net investment income | 0 | 0
Net investment gains (losses) | 0 | 0
Products revenues | 0 | 0
Services and other revenues | 0 | 0
Operating revenues | 271,549 | 253,339
Attritional Current Year Claims and Claims Adjustment Expense | (181,753) | (163,215)
Catastrophe Current Year Claims and Claims Adjustment Expense | (1,950) | 0
Losses and loss adjustment expenses, prior accident year | 14,258 | (3,398)
Amortization of policy acquisition costs | (62,502) | (60,809)
Other underwriting expenses | (14,569) | (13,907)
Products expenses | 0 | 0
Services and other expenses | 0 | 0
Operating Income | 25,033 | 12,010
Investing [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | 0 | 0
Net investment income | 235,601 | 217,204
Net investment gains (losses) | (149,071) | 902,281
Products revenues | 0 | 0
Services and other revenues | (4,610) | 20,846
Operating revenues | 81,920 | 1,140,331
Attritional Current Year Claims and Claims Adjustment Expense | 0 | 0
Catastrophe Current Year Claims and Claims Adjustment Expense | 0 | 0
Losses and loss adjustment expenses, prior accident year | 0 | 0
Amortization of policy acquisition costs | 0 | 0
Other underwriting expenses | 0 | 0
Products expenses | 0 | 0
Services and other expenses | 0 | 0
Operating Income | 81,920 | 1,140,331
Markel Ventures [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | 0 | 0
Net investment income | 1,494 | 1,065
Net investment gains (losses) | 0 | 0
Products revenues | 561,124 | 600,840
Services and other revenues | 566,754 | 538,701
Operating revenues | 1,129,372 | 1,140,606
Attritional Current Year Claims and Claims Adjustment Expense | 0 | 0
Catastrophe Current Year Claims and Claims Adjustment Expense | 0 | 0
Losses and loss adjustment expenses, prior accident year | 0 | 0
Amortization of policy acquisition costs | 0 | 0
Other underwriting expenses | 0 | 0
Products expenses | (499,908) | (523,247)
Services and other expenses | (526,954) | (513,444)
Operating Income | 102,510 | 103,915
Other Insurance Operations [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | (26) | (173)
Net investment income | 0 | 0
Net investment gains (losses) | 0 | 0
Products revenues | 0 | 0
Services and other revenues | 98,439 | 58,091
Operating revenues | 98,413 | 57,918
Attritional Current Year Claims and Claims Adjustment Expense | 0 | 0
Catastrophe Current Year Claims and Claims Adjustment Expense | 0 | 0
Losses and loss adjustment expenses, prior accident year | 9,397 | (16,760)
Amortization of policy acquisition costs | 0 | 0
Other underwriting expenses | (349) | (1,259)
Products expenses | 0 | 0
Services and other expenses | (40,674) | (23,394)
Operating Income | 66,787 | 16,505
Corporate [Member] |  |
Segment Reporting Information [Line Items] |  |
Earned premiums | 0 | 0
Net investment income | 0 | 0
Net investment gains (losses) | 0 | 0
Products revenues | 0 | 0
Services and other revenues | 0 | 0
Operating revenues | 0 | 0
Attritional Current Year Claims and Claims Adjustment Expense | 0 | 0
Catastrophe Current Year Claims and Claims Adjustment Expense | 0 | 0
Losses and loss adjustment expenses, prior accident year | 0 | 0
Amortization of policy acquisition costs | 0 | 0
Other underwriting expenses | 0 | 0
Products expenses | 0 | 0
Services and other expenses | 0 | 0
Amortization of acquired intangible assets | (46,942) | (44,285)
Operating Income | $ (46,942) | $ (44,285)

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