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Fair Value Measurements (Summary Of Changes In Level 3 Investments Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jan. 01, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Purchases | $ 90,000 | $ 0 | $ 90,000 | $ 500 | $ 90,000 | $ 500
Equity securities, beginning of period | 45,992 | 131,307 | 45,992 | 44,812 | 45,992 | 53,728
Purchases | $ 90,000 | 0 | 90,000 | 500 | 90,000 | 500
Sales |  | (16,529) |  | 0 | (17,893) | (6,869)
Net investment gains (losses) on Level 3 investments |  | 870 |  | (7,324) | (2,451) | (9,371)
Transfers into level 3 |  | 0 |  | 0 | 0 | 0
Transfers out of level 3 |  | 0 |  | 0 | 0 | 0
Equity securities, end of period |  | 115,648 | $ 131,307 | 37,988 | 115,648 | 37,988
Sales of fixed maturities [Member] |  |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |  |
Fixed maturity securities, realized gains |  | $ 5,348 |  | $ 1,661 | $ 6,733 | $ 1,804

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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27357-111563 + Details
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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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- Definition Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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