Investments (Summary Of Changes In Net Unrealized Appreciation (Depreciation) For The Company's Investments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Change in unrealized appreciation (depreciation), pre-tax	$ 60,946	$ 33,993
Deferred tax benefit (expense)	(17,924)us-gaap_DeferredIncomeTaxExpenseBenefit	(11,898)us-gaap_DeferredIncomeTaxExpenseBenefit
Deferred tax benefit (expense), other-than-temporary impairment	(3,407)
Change in unrealized appreciation (depreciation), net of deferred taxes, included in stockholder's equity	39,615	22,095
Fixed Maturity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Change in unrealized appreciation (depreciation), pre-tax	51,211	33,993
Fixed Maturity Securities, Other-Than-Temporary Impairment [Member]
Schedule of Available-for-sale Securities [Line Items]
Change in unrealized appreciation (depreciation), pre-tax	$ 9,735

Cumulative Other Than Temporary Impairment Adjustment Deferred Tax Benefit Expense.

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- Definition

This item represents the pretax change in net unrealized holding gain (loss) on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

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The change in unrealized holding gain (loss), net of tax, on available-for-sale securities included in a separate component of shareholders' equity during the period.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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-Glossary Deferred Tax Expense (or Benefit)

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