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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance | $ (767,494) |  |  |
Income tax (expense) benefit | (552,616) | $ 48,209 | $ (683,961) |
Accumulated other comprehensive income (loss), ending balance | (478,210) | (767,494) |  |
Unrealized Gains (Losses) On Available-For-Sale Investments [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance | (766,276) | 388,554 | 793,253 |
Total other comprehensive income (loss) before income taxes | 390,558 | (1,463,876) | (513,084) |
Income tax (expense) benefit | (83,655) | 309,046 | 108,385 |
Total other comprehensive income (loss) | 306,903 | (1,154,830) | (404,699) |
Accumulated other comprehensive income (loss), ending balance | (459,373) | (766,276) | 388,554 |
Unrealized Gains (Losses) On Available-For-Sale Investments [Member] | Cumulative effect of adoption of ASU No. 2018-12 |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cumulative Effect of Adoption of ASU No. 2018-12, Net of Tax |  |  |  | $ 94,443
Unrealized Gains (Losses) On Available-For-Sale Investments [Member] | Previously Reported [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance |  |  | 698,810 |
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 | 89,583 | (60,291) | (109,702) |
Total other comprehensive income (loss) before income taxes | (28,281) | 189,714 | 62,546 |
Income tax (expense) benefit | 5,938 | (39,840) | (13,135) |
Total other comprehensive income (loss) | (22,343) | 149,874 | 49,411 |
Accumulated other comprehensive income (loss), ending balance | 67,240 | 89,583 | (60,291) |
Accumulated Life and Annuity Discount Rate Assumption Adjustment Attributable to Parent | Cumulative effect of adoption of ASU No. 2018-12 |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cumulative Effect of Adoption of ASU No. 2018-12, Net of Tax |  |  |  | (109,702)
Accumulated Life and Annuity Discount Rate Assumption Adjustment Attributable to Parent | Previously Reported [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance |  |  | 0 |
Foreign Currency [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance | (65,907) | (56,631) | (56,420) |
Total other comprehensive income (loss) before income taxes | 4,650 | (9,677) | (2,091) |
Income tax (expense) benefit | 0 | 401 | 1,880 |
Total other comprehensive income (loss) | 4,650 | (9,276) | (211) |
Accumulated other comprehensive income (loss), ending balance | (61,257) | (65,907) | (56,631) |
Foreign Currency [Member] | Cumulative effect of adoption of ASU No. 2018-12 |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cumulative Effect of Adoption of ASU No. 2018-12, Net of Tax |  |  |  | 0
Foreign Currency [Member] | Previously Reported [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance |  |  | (56,420) |
Net Actuarial Pension Loss [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance | (24,894) | (49,624) | (58,014) |
Total other comprehensive income (loss) before income taxes | 94 | 31,222 | 10,663 |
Income tax (expense) benefit | (20) | (6,492) | (2,273) |
Total other comprehensive income (loss) | 74 | 24,730 | 8,390 |
Accumulated other comprehensive income (loss), ending balance | (24,820) | (24,894) | (49,624) |
Net Actuarial Pension Loss [Member] | Cumulative effect of adoption of ASU No. 2018-12 |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cumulative Effect of Adoption of ASU No. 2018-12, Net of Tax |  |  |  | 0
Net Actuarial Pension Loss [Member] | Previously Reported [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance |  |  | (58,014) |
Accumulated Other Comprehensive Income (Loss) [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance | (767,494) | 222,008 | 569,117 |
Total other comprehensive income (loss) before income taxes | 367,021 | (1,252,617) | (441,966) |
Income tax (expense) benefit | (77,737) | 263,115 | 94,857 |
Total other comprehensive income (loss) | 289,284 | (989,502) | (347,109) |
Accumulated other comprehensive income (loss), ending balance | $ (478,210) | $ (767,494) | 222,008 |
Accumulated Other Comprehensive Income (Loss) [Member] | Cumulative effect of adoption of ASU No. 2018-12 |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Cumulative Effect of Adoption of ASU No. 2018-12, Net of Tax |  |  |  | $ (15,259)
Accumulated Other Comprehensive Income (Loss) [Member] | Previously Reported [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Accumulated other comprehensive income (loss), beginning balance |  |  | $ 584,376 |

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