Investments (Summary Of Gross Unrealized Gains And Losses And Fair Values) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 141,003	$ 114,179
Available-for-sale Securities, Gross Unrealized Gains	15,795	9,716
Available-for-sale Securities, Gross Unrealized Losses	(149)	(158)
Available-for-sale Securities	156,649us-gaap_AvailableForSaleSecurities	123,737us-gaap_AvailableForSaleSecurities
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	91,456	66,587
Available-for-sale Securities, Gross Unrealized Gains	147	134
Available-for-sale Securities, Gross Unrealized Losses	(136)	(29)
Available-for-sale Securities	91,467	66,692
US Treasury and Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	26,848	23,689
Available-for-sale Securities, Gross Unrealized Gains	9	20
Available-for-sale Securities, Gross Unrealized Losses	(13)	(7)
Available-for-sale Securities	26,844	23,702
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	2,088	3,293
Available-for-sale Securities, Gross Unrealized Gains	5	4
Available-for-sale Securities, Gross Unrealized Losses	0	(1)
Available-for-sale Securities	2,093	3,296
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	20,611	20,610
Available-for-sale Securities, Gross Unrealized Gains	15,634	9,558
Available-for-sale Securities, Gross Unrealized Losses	0	(121)
Available-for-sale Securities	$ 36,245	$ 30,047

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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