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Other Comprehensive Income (Loss) (Change In Accumulated Other Comprehensive Income By Component, Net Of Noncontrolling Interests) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | $ (478,210) |  |
Income tax (expense) benefit | (790,294) | $ (552,616) | $ 48,209
Accumulated other comprehensive income (loss), ending balance | (617,082) | (478,210) |
Unrealized Gains (Losses) On Available-For-Sale Investments [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | (459,373) | (766,276) | 388,554
Total other comprehensive income (loss) before income taxes | (165,423) | 390,558 | (1,463,876)
Income tax (expense) benefit | 35,128 | (83,655) | 309,046
Total other comprehensive income (loss) | (130,295) | 306,903 | (1,154,830)
Accumulated other comprehensive income (loss), ending balance | (589,668) | (459,373) | (766,276)
Accumulated Life and Annuity Discount Rate Assumption Adjustment Attributable to Parent |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | 67,240 | 89,583 | (60,291)
Total other comprehensive income (loss) before income taxes | 319 | (28,281) | 189,714
Income tax (expense) benefit | (67) | 5,938 | (39,840)
Total other comprehensive income (loss) | 252 | (22,343) | 149,874
Accumulated other comprehensive income (loss), ending balance | 67,492 | 67,240 | 89,583
Foreign Currency [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | (61,257) | (65,907) | (56,631)
Total other comprehensive income (loss) before income taxes | (3,883) | 4,650 | (9,677)
Income tax (expense) benefit | 0 | 0 | 401
Total other comprehensive income (loss) | (3,883) | 4,650 | (9,276)
Accumulated other comprehensive income (loss), ending balance | (65,140) | (61,257) | (65,907)
Net Actuarial Pension Loss [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | (24,820) | (24,894) | (49,624)
Total other comprehensive income (loss) before income taxes | (6,600) | 94 | 31,222
Income tax (expense) benefit | 1,654 | (20) | (6,492)
Total other comprehensive income (loss) | (4,946) | 74 | 24,730
Accumulated other comprehensive income (loss), ending balance | (29,766) | (24,820) | (24,894)
Accumulated Other Comprehensive Income (Loss) [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated other comprehensive income (loss), beginning balance | (478,210) | (767,494) | 222,008
Total other comprehensive income (loss) before income taxes | (175,587) | 367,021 | (1,252,617)
Income tax (expense) benefit | 36,715 | (77,737) | 263,115
Total other comprehensive income (loss) | (138,872) | 289,284 | (989,502)
Accumulated other comprehensive income (loss), ending balance | $ (617,082) | $ (478,210) | $ (767,494)

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