Investments (Components Of Net Realized and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)	$ 2,883	$ 54	$ 6,327	$ 4,785
OTTI Charges	(971)	(2,821)	(1,075)	(4,033)
Net realized gains (losses)	1,912	(2,767)	5,252	752
Unrealized gains (losses) recognized in income on equity securities	2,115	1,115	12,226	(12,953)
Net realized and unrealized gains (losses)	4,027	(1,652)	17,478	(12,201)
Fixed Income Securities [Member]
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)	2,061	(1,174)	3,204	(4,509)
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)	851	1,226	3,131	9,295
Short-Term Investments [Member]
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)	1	2	15	(1)
Other Investments [Member]
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)	$ (30)	$ 0	$ (23)	$ 0

Aggregate net change in unrealized gains or losses on the equity portfolio recognized in net income for the period.

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Amount of unrealized and realized gain (loss) on investment in debt and equity securities.

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Amount of realized and unrealized gain (loss) on investment.

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Amount of realized gain (loss) on investment in marketable security, excluding other-than-temporary impairment (OTTI).

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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.

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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.

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