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Supplemental Financial Statement Data (Schedule of Other Operating Cost and Expense, by Component) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Other Income and Expenses [Abstract] |  |  |
Amortization of deferred policy acquisition costs | $ 1,219,849 | $ 1,038,975 | $ 1,038,903
Insurance operating expenses | 2,075,053 | 1,915,711 | 1,635,000
Insurance service expenses | 90,640 | 91,714 | 96,419
Net foreign currency (gains) losses | (52,376) | 31,799 | (50,930)
Other costs and expenses | 269,140 | 285,737 | 242,113
Total | $ 3,602,306 | $ 3,363,936 | $ 2,961,505

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