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Condensed Financial Information of Registrant (Schedule Of Condensed Financial Information Of Registrant, Statements Of Cash Flow) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Cash flows from operating activities: |  |  |
Net cash provided by operating activities | $ 352,589,000 | $ 501,584,000 | $ 605,616,000
Cash flows from investing activities: |  |  |
Capital distribution from subsidiaries | 2,900,000 | 5,200,000 | 12,100,000
Fixed maturity securities available for sale in nature: |  |  |
Purchases | (1,794,817,000) | (1,460,641,000) | (878,213,000)
Sales | 856,291,000 | 336,201,000 | 168,087,000
Equity securities available for sale in nature |  |  |
Purchases | (1,042,913,000) | (958,008,000) | (1,230,785,000)
Sales | 1,154,523,000 | 943,857,000 | 1,174,540,000
Other, net | 5,752,000 | 9,096,000 | 20,577,000
Net cash used in investing activities | (316,384,000) | (373,670,000) | (411,286,000)
Cash flows from financing activities: |  |  |
Dividends paid to shareholders | (105,482,000) | (140,226,000) | (139,640,000)
Proceeds from stock options exercised | 0 | 215,000 | 0
Proceeds from bank loan | 25,000,000 | 0 | 0
Net cash used in financing activities | (81,986,000) | (140,836,000) | (140,249,000)
Net (decrease) increase in cash | (45,781,000) | (12,922,000) | 54,081,000
Cash: |  |  |
Beginning of year | 335,557,000 | 348,479,000 | 294,398,000
End of year | 289,776,000 | 335,557,000 | 348,479,000
SUPPLEMENTAL CASH FLOW DISCLOSURE |  |  |
Interest paid | 16,665,000 | 16,616,000 | 16,599,000
Income taxes (refunded) paid, net | (26,542,000) | 69,467,000 | 52,659,000
Parent Company |  |  |
Cash flows from operating activities: |  |  |
Net cash provided by operating activities | 225,000 | (36,662,000) | (17,339,000)
Cash flows from investing activities: |  |  |
Capital contribution to subsidiaries | 0 | 0 | (30,000,000)
Capital distribution from subsidiaries | 3,431,433 | 0 | 0
Distributions received from special purpose entities | 2,904,000 | 5,199,000 | 12,129,000
Dividends received from subsidiaries | 0 | 191,000,000 | 121,000,000
Fixed maturity securities available for sale in nature: |  |  |
Purchases | (11,905,000) | 0 | 0
Sales | 1,000,000 | 0 | 0
Equity securities available for sale in nature |  |  |
Purchases | (5,307,000) | (13,151,000) | (54,571,000)
Sales | 48,215,000 | 38,092,000 | 67,965,000
(Increase) decrease in short-term investments | (6,268,000) | (16,172,000) | 25,088,000
Other, net | 667,000 | 791,000 | 254,000
Net cash used in investing activities | 32,737,000 | 205,759,000 | 141,865,000
Cash flows from financing activities: |  |  |
Dividends paid to shareholders | (105,482,000) | (140,226,000) | (139,640,000)
Proceeds from stock options exercised | 0 | 215,000 | 0
Proceeds from bank loan | 25,000,000 | 0 | 0
Net cash used in financing activities | (80,482,000) | (140,011,000) | (139,640,000)
Net (decrease) increase in cash | (47,520,000) | 29,086,000 | (15,114,000)
Cash: |  |  |
Beginning of year | 53,738,000 | 24,652,000 | 39,766,000
End of year | 6,218,000 | 53,738,000 | 24,652,000
SUPPLEMENTAL CASH FLOW DISCLOSURE |  |  |
Interest paid | 16,611,000 | 16,590,000 | 16,586,000
Income taxes (refunded) paid, net | $ (14,102,000) | $ 18,841,000 | $ (20,552,000)

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