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v3.25.3

Business Segments (Financial Information of Company Operating Segments) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) segment | Sep. 30, 2024 USD ($)
Segment Reporting [Abstract] |  |  |  |
Number of reportable segments | segment |  |  | 2 |
Number of operating segments | segment |  |  | 3 |
Segment Reporting Information [Line Items] |  |  |  |
Premiums Earned, Net | $ 3,156,382 | $ 2,926,823 | $ 9,266,948 | $ 8,537,585
Investment Income | 351,238 | 323,756 | 1,090,833 | 1,015,723
Other | 260,616 | 149,800 | 628,662 | 417,876
Total revenues | 3,768,236 | 3,400,379 | 10,986,443 | 9,971,184
Net Income (Loss) to Common Stockholders | 511,032 | 365,634 | 1,329,892 | 1,180,014
Net investment gains | 78,960 | (8,086) | 126,288 | (40,818)
Net investment gains, net of tax | 61,987 | (8,043) | 99,102 | (35,008)
Income before income taxes | 648,110 | 474,449 | 1,708,579 | 1,536,192
Policyholder Benefits and Claims Incurred, Net | 1,968,857 | 1,825,960 | 5,825,073 | 5,270,334
Policy Acquisition And Insurance Operating Expenses | 900,312 | 835,376 | 2,620,657 | 2,438,905
Other segment amount | 250,957 | 264,594 | 832,134 | 725,753
Total | 3,120,126 | 2,925,930 | 9,277,864 | 8,434,992
Net investment gains (losses) | 78,960 | (8,086) | 126,288 | (40,818)
Corporate Reconciling Items And Eliminations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Investment Income | 19,069 | 13,485 | 20,652 | 45,429
Other | 171,619 | 148,697 | 472,230 | 430,492
Total revenues | 190,688 | 162,182 | 492,882 | 475,921
Net Income (Loss) to Common Stockholders | (39,593) | (72,008) | (240,302) | (169,764)
Income before income taxes | (49,396) | (92,111) | (306,111) | (217,912)
Other segment amount | 240,084 | 254,293 | 798,993 | 693,833
Total | 240,084 | 254,293 | 798,993 | 693,833
Segment Reporting, Reconciling Item, Corporate Nonsegment |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Income before income taxes | 78,960 | (8,086) | 126,288 | (40,818)
Net investment gains (losses) | 78,960 |  |  |
Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Premiums Earned, Net |  | 2,564,490 |  | 7,447,828
Insurance | Operating Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Premiums Earned, Net | 2,773,009 | 2,564,490 | 8,144,300 | 7,447,828
Investment Income | 260,547 | 253,234 | 851,271 | 801,573
Other | 10,037 | 9,189 | 30,144 | 28,202
Total revenues | 3,043,593 | 2,826,913 | 9,025,715 | 8,277,603
Net Income (Loss) to Common Stockholders | 375,577 | 363,026 | 1,162,148 | 1,102,363
Income before income taxes | 474,538 | 469,421 | 1,496,715 | 1,437,623
Policyholder Benefits and Claims Incurred, Net | 1,772,377 | 1,619,281 | 5,202,065 | 4,690,402
Policy Acquisition And Insurance Operating Expenses | 785,805 | 727,910 | 2,293,794 | 2,117,658
Other segment amount | 10,873 | 10,301 | 33,141 | 31,920
Total | 2,569,055 | 2,357,492 | 7,529,000 | 6,839,980
Insurance | Operating Segments | Non-US |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | 357,000 | 350,000 | 1,051,000 | 1,112,000
Reinsurance & Monoline Excess |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Premiums Earned, Net |  | 362,333 |  | 1,089,757
Reinsurance & Monoline Excess | Operating Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Premiums Earned, Net | 383,373 | 362,333 | 1,122,648 | 1,089,757
Investment Income | 71,622 | 57,037 | 218,910 | 168,721
Other | 0 | 0 | 0 | 0
Total revenues | 454,995 | 419,370 | 1,341,558 | 1,258,478
Net Income (Loss) to Common Stockholders | 113,061 | 82,659 | 308,944 | 282,423
Income before income taxes | 144,008 | 105,225 | 391,687 | 357,299
Policyholder Benefits and Claims Incurred, Net | 196,480 | 206,679 | 623,008 | 579,932
Policy Acquisition And Insurance Operating Expenses | 114,507 | 107,466 | 326,863 | 321,247
Total | 310,987 | 314,145 | 949,871 | 901,179
Reinsurance & Monoline Excess | Operating Segments | Non-US |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Total revenues | $ 136,000 | $ 125,000 | $ 382,000 | $ 353,000

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