Investments (Schedule Of Available-For-Sale And Trading Securities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investments [Abstract]
Trading	$ 1	$ 2
Available-for-sale Securities	147,405	73,589
Total	$ 147,406	$ 73,591

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

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- Definition

Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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- Definition

The total of financial instruments that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt and equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition.

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