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Short-Term And Long-Term Investments And Restricted Deposits (Narrative) (Details) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
|---|---|---|---|
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Dec. 31, 2012
positions
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Dec. 31, 2011
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Dec. 31, 2010
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| Investments, Debt and Equity Securities [Abstract] | |||
| Percentage of investments in securities recorded at fair value that carry a rating by S&P or Moody's of AAA/Aaa | 40.00% | ||
| Percentage of investments in securities recorded at fair value that carry a rating by S&P or Moody's of AA-/Aa3 or higher | 61.00% | ||
| Percentage of investments in securities recorded at fair value that carry a rating by S&P or Moody's of A-/A3 or higher | 95.00% | ||
| Positions from which gross unrealized losses were generated | 34 | ||
| Total number of positions | 371 | ||
| Net realized gains from sales | $ 1,484 | $ 287 | $ 235 |
| Georgia investment portfolio liquidated | 75,468 | ||
| Impairment charge | 0 | 0 | 5,531 |
| Impairment of convertible promissory notes | 3,531 | ||
| Investment amortization | $ 11,151 | $ 10,335 | $ 10,750 |
| X | ||||||||||
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- Definition
Impairment Of Convertible Promissory Notes No definition available.
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- Definition
Georgia Investment Portfolio liquidated in Q3 2012. No definition available.
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- Definition
The percentage of investments in securities recorded at fair value that carry a rating by Moody's or S&P of AAA. No definition available.
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- Definition
The percentage of investments in securities recorded at fair value that carry a rating by Moody's or S&P of AA- or higher. No definition available.
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- Definition
The percentage of investments in securities recorded at fair value that carry a rating by Moody's or S&P of A- or higher. No definition available.
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| X | ||||||||||
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- Definition
Positions from which gross unrealized losses were generated No definition available.
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- Definition
Total Unrealized Investment Positions No definition available.
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| X | ||||||||||
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- Definition
The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
This item represents the net amount of amortization of purchase discounts and premiums related to investments in debt securities. The purchase discount or premium is amortized to income or expense, respectively, over the life (holding period) of the securities to arrive at an amount of periodic interest income or expense which results in a constant effective yield on the investments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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| X | ||||||||||
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- Definition
This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. No definition available.
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