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Investments (Components Of Net Realized and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Gain (Loss) on Investments [Line Items] |  |  |  |  |
Net realized (losses) gains on disposals of securities, fixed income securities |  | $ (1,174) | $ 2,606 | $ (4,509) | $ 4,570
Total net realized gains on the disposal of securities (excluding OTTI charges) |  | 54 | 2,951 | 4,785 | 5,381
OTTI Charges |  | (2,821) | (1,217) | (4,033) | (4,692)
Net realized investment (losses) gains |  | (2,767) | 1,734 | 752 | 689
Unrealized gains (losses) recognized in income on equity securities | [1] | 1,115 | 0 | (12,953) | 0
Total net realized and unrealized (losses) gains |  | (1,652) | 1,734 | (12,201) | 689
Unrealized holding gains (losses) on equity securities |  | 2,300 |  | (2,700) |
Unrealized losses on equity securities sold during the period |  | (1,200) |  | (10,300) |
Equity Securities [Member] |  |  |  |  |
Gain (Loss) on Investments [Line Items] |  |  |  |  |
Total net realized gains on the disposal of securities (excluding OTTI charges) |  | 1,226 | 350 | 9,295 | 350
Short-Term Investments [Member] |  |  |  |  |
Gain (Loss) on Investments [Line Items] |  |  |  |  |
Total net realized gains on the disposal of securities (excluding OTTI charges) |  | 2 | 0 | (1) | 0
Other Investments [Member] |  |  |  |  |
Gain (Loss) on Investments [Line Items] |  |  |  |  |
Total net realized gains on the disposal of securities (excluding OTTI charges) |  | $ 0 | $ (5) | $ 0 | $ 461
[1] | Includes unrealized holding gains (losses) of: (i) $2.3 million in Second Quarter 2018 and $(2.7) million in Six Months 2018 on equity securities remaining in our portfolio as of June 30, 2018; and (ii) $(1.2) million in Second Quarter 2018 and $(10.3) million in Six Months 2018 on equity securities sold during the period.

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- Definition The unrealized gains (losses) on equity securities sold during the period. + References No definition available. + Details
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- Definition Aggregate net change in unrealized gains or losses on the equity portfolio recognized in net income for the period. + References No definition available. + Details
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- Definition This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (c)-(e) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(c),9(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563 + Details
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- Definition The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(h)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 + Details
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- Definition The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8B -URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563 + Details
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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 325 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031664&loc=d3e22529-158502 + Details
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- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
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