Fair Value Measurements And Marketable Securities (Contractual Maturities Of Available For Sale Investments) (Details) (USD $)	Sep. 30, 2011	Dec. 31, 2010
Fair Value Measurements And Marketable Securities
Maturing in one year or less	$ 4,266,000	$ 313,000
Maturing after one year through three years	23,319,000	22,325,000
Maturing after three years	7,178,000	2,202,000
Total debt securities - available for sale	$ 34,763,000	$ 24,840,000

For an unclassified balance sheet, this item represents investments in debt and equity securities which are categorized neither as held-to-maturity nor trading.

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+ Details