Financial Instruments And Investments (Contractual Year For Maturity Of Available-For-Sale Securities ) (Details) $ in Thousands	9 Months Ended
Sep. 30, 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	$ 22,136
2016	417
2017 through 2020	7,909
2021 through 2025	12,730
2026 and Beyond	1,080
Corporate Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Total	24,129
2016	0
2017 through 2020	5,501
2021 through 2025	9,941
2026 and Beyond	8,687
U.S. Government Bonds
Schedule of Available-for-sale Securities [Line Items]
Total	56,739
2016	0
2017 through 2020	29,297
2021 through 2025	14,542
2026 and Beyond	$ 12,900
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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