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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, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Revenues: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | $ 124,930 | $ 121,871 | $ 126,299
Net realized investment gains (losses) |  |  |  |  |  |  |  |  | 83,650 | (34,255) | (83,807)
Other |  |  |  |  |  |  |  |  | 11,945 | 8,294 | 8,911
Total revenues |  |  |  |  |  |  |  |  | 3,415,962 | 3,227,683 | 3,009,300
Expenses: |  |  |  |  |  |  |  |  |  |  |
Other operating expenses |  |  |  |  |  |  |  |  | 233,475 | 235,314 | 250,839
Interest |  |  |  |  |  |  |  |  | 15,168 | 3,962 | 3,168
Total expenses |  |  |  |  |  |  |  |  | 3,248,877 | 3,156,959 | 2,938,733
Income before income taxes | $ 9,487 | $ 58,247 | $ 68,752 | $ 30,599 | $ (51,270) | $ 31,625 | $ 64,335 | $ 26,034 | 167,085 | 70,724 | 70,567
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 22,208 | (2,320) | (3,912)
Net income | $ 19,779 | $ 46,485 | $ 51,633 | $ 26,980 | $ (26,082) | $ 26,930 | $ 48,873 | $ 23,323 | 144,877 | 73,044 | 74,479
Parent Company [Member] |  |  |  |  |  |  |  |  |  |  |
Revenues: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | 4,090 | 4,032 | 4,314
Net realized investment gains (losses) |  |  |  |  |  |  |  |  | 19,279 | 6,062 | (7,026)
Other |  |  |  |  |  |  |  |  | 0 | 17 | 0
Total revenues |  |  |  |  |  |  |  |  | 23,369 | 10,111 | (2,712)
Expenses: |  |  |  |  |  |  |  |  |  |  |
Other operating expenses |  |  |  |  |  |  |  |  | 1,918 | 2,673 | 7,526
Interest |  |  |  |  |  |  |  |  | 14,856 | 2,690 | 2,127
Total expenses |  |  |  |  |  |  |  |  | 16,774 | 5,363 | 9,653
Income before income taxes |  |  |  |  |  |  |  |  | 6,595 | 4,748 | (12,365)
Income tax expense (benefit) |  |  |  |  |  |  |  |  | 1,572 | 8,514 | (4,708)
Income (loss) before equity in net income of subsidiaries |  |  |  |  |  |  |  |  | (5,023) | 3,766 | 7,657
Equity in net income of subsidiaries |  |  |  |  |  |  |  |  | 139,854 | 76,810 | 82,136
Net income |  |  |  |  |  |  |  |  | $ 144,877 | $ 73,044 | $ 74,479

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