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Investments (Components Of Net Investment Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Municipal bonds (tax-exempt) | $ 16,157 | $ 17,885 | $ 32,758 | $ 36,711
Short-term investments, including overnight deposits | 2,379 | 13,753 | 12,622 | 23,965
Dividends on equity securities | 18,020 | 22,207 | 46,634 | 47,993
Income (loss) from equity method investments | 5,647 | 1,174 | (14,332) | 3,070
Other | 46 | 873 | 803 | 3,174
Total investment income | 98,699 | 115,747 | 191,802 | 234,128
Investment expenses | (3,084) | (3,916) | (7,944) | (8,115)
Net investment income | 95,615 | 111,831 | 183,858 | 226,013
Municipal Bonds (taxable) [Member] |  |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Taxable bonds | 16,834 | 18,613 | 33,729 | 37,192
Other taxable bonds [Member] |  |  |  |
Schedule of Investment Income, Reported Amounts, by Category [Line Items] |  |  |  |
Taxable bonds | $ 39,616 | $ 41,242 | $ 79,588 | $ 82,023

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