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Investments (Components Of Net Realized and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Gain (Loss) on Securities [Line Items]
Net realized (losses) gains on disposals of securities, fixed income securities (excluding OTTI charges)		$ (9,413)	$ 1,996	$ (13,922)	$ 6,566
Total net realized gains on the disposal of securities (excluding OTTI charges)		(751)	6,871	4,034	12,252
OTTI Charges		(1,426)	(73)	(5,459)	(4,765)
Net realized (losses) gains		(2,177)	6,798	(1,425)	7,487
Unrealized (losses) recognized in income on equity securities	[1]	(2,610)	0	(15,563)	0
Total net realized and unrealized (losses) gains		(4,787)	6,798	(16,988)	7,487
Unrealized holding gains (losses) on equity securities		5,500		4,200
Unrealized losses on equity securities sold during the period		(8,100)		(19,800)
Equity Securities [Member]
Gain (Loss) on Securities [Line Items]
Total net realized gains on the disposal of securities (excluding OTTI charges)		8,665	4,875	17,960	5,225
Short-Term Investments [Member]
Gain (Loss) on Securities [Line Items]
Total net realized gains on the disposal of securities (excluding OTTI charges)		2	0	1	0
Other Investments [Member]
Gain (Loss) on Securities [Line Items]
Total net realized gains on the disposal of securities (excluding OTTI charges)		$ (5)	$ 0	$ (5)	$ 461
[1] Includes unrealized holding gains (losses) of: (i) $5.5 million in Third Quarter 2018 and $4.2 million in Nine Months 2018 on equity securities remaining in our portfolio as of September 30, 2018; and (ii) $(8.1) million in Third Quarter 2018 and $(19.8) million in Nine Months 2018 on equity securities sold during the respective periods.

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The unrealized gains (losses) on equity securities sold during the period.

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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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