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Investments (Estimated Fair Value Of Investments) (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020
Fixed maturity securities: |  |
Due in one year or less | $ 403,269 |
Due after one year through five years | 791,879 |
Due after five years through ten years | 806,813 |
Due after ten years | 2,029,562 |
Total | $ 4,031,523 | $ 3,549,810
External credit rating, non investment grade [Member] |  |
Credit Derivatives [Line Items] |  |
Percentage of fixed maturities | 0.40% |

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 + Details
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