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Condensed Financial Information of Registrant (Schedule Of Condensed Financial Information Of Registrant, Statements Of Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Revenues: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | $ 121,871 | $ 126,299 | $ 125,723
Net realized investment (losses) gains |  |  |  |  | $ (8,200) |  |  |  | (34,255) | (83,807) | 81,184
Other |  |  |  |  |  |  |  |  | 8,294 | 8,911 | 8,671
Total revenues |  |  |  |  |  |  |  |  | 3,227,683 | 3,009,300 | 3,011,773
Expenses: |  |  |  |  |  |  |  |  |  |  |
Other operating expenses |  |  |  |  |  |  |  |  | 235,314 | 250,839 | 249,381
Interest |  |  |  |  |  |  |  |  | 3,962 | 3,168 | 2,637
Total expenses |  |  |  |  |  |  |  |  | 3,156,959 | 2,938,733 | 2,764,348
Pre-tax income | $ (51,270) | $ 31,625 | $ 64,335 | $ 26,034 | 23,930 | $ 12,267 | $ 4,511 | $ 29,859 | 70,724 | 70,567 | 247,425
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 2,320 | 3,912 | (69,476)
Net income | $ (26,082) | $ 26,930 | $ 48,873 | $ 23,323 | $ 23,405 | $ 15,270 | $ 9,639 | $ 26,165 | 73,044 | 74,479 | 177,949
Parent Company [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | 4,032 | 4,314 | 4,478
Net realized investment (losses) gains |  |  |  |  |  |  |  |  | 6,062 | (7,026) | (9,428)
Other |  |  |  |  |  |  |  |  | 17 | 0 | 0
Total revenues |  |  |  |  |  |  |  |  | 10,111 | (2,712) | (4,950)
Expenses: |  |  |  |  |  |  |  |  |  |  |
Other operating expenses |  |  |  |  |  |  |  |  | 2,673 | 7,526 | 5,971
Interest |  |  |  |  |  |  |  |  | 2,690 | 2,127 | 1,746
Total expenses |  |  |  |  |  |  |  |  | 5,363 | 9,653 | 7,717
Pre-tax income |  |  |  |  |  |  |  |  | 4,748 | (12,365) | (12,667)
Income tax expense (benefit) |  |  |  |  |  |  |  |  | (8,514) | 4,708 | 100
Loss before equity in net income of subsidiaries |  |  |  |  |  |  |  |  | (3,766) | (7,657) | (12,567)
Equity in net income of subsidiaries |  |  |  |  |  |  |  |  | 73,864 | 82,136 | 190,516
Net income |  |  |  |  |  |  |  |  | $ 70,098 | $ 74,479 | $ 177,949

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