Financial Instruments And Investments (Contractual Year For Maturity Of Available-For-Sale Securities ) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($)
Collateralized Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Contractual Maturity Due For, Mortgaged Backed Securities	10 years
Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Total	$ 22,872
2016	717
2017 through 2020	9,302
2021 through 2025	11,340
2026 and Beyond	1,513
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Total	22,147
2016	0
2017 through 2020	5,863
2021 through 2025	8,389
2026 and Beyond	7,895
U.S. Government Bonds
Schedule of Available-for-sale Securities [Line Items]
Total	54,879
2016	3,413
2017 through 2020	25,654
2021 through 2025	14,189
2026 and Beyond	$ 11,623
Minimum \| Collateralized Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Debt Instrument, Expected Weighted Average Maturity Year	2 years
Maximum \| Collateralized Mortgage Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Debt Instrument, Expected Weighted Average Maturity Year	6 years

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of debt securities categorized neither as held-to-maturity nor trading.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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