Cash Equivalents And Investments (Schedule Of Estimated Fair Value Of Available-For-Sale Securities) (Details) - USD ($) |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Schedule of Available-for-sale Securities [Line Items] | ||
| Estimated Market Value | $ 11,734,000 | $ 9,656,000 |
| Investments [Member] | ||
| Schedule of Available-for-sale Securities [Line Items] | ||
| Amortized Cost, Due within one year | 5,542,000 | |
| Amortized Cost, Due after one year through five years | 0 | |
| Amortized Cost | 5,542,000 | |
| Estimated Market Value, Due within one year | 5,541,000 | |
| Estimated Market Value, Due after one year through five years | 0 | |
| Estimated Market Value | $ 5,541,000 | $ 5,805,000 |
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- Definition This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the next rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the second through fifth rolling twelve months following the latest balance sheet. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. No definition available.
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- Details
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