Fair Value Measurements (Contractual Maturities Of Available For Sale Investments) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value Disclosures [Abstract]
Maturing in one year or less	$ 3,223	$ 5,164
Maturing after one year through three years	6,102	12,134
Maturing after three years	2,237	4,024
Total debt securities	$ 11,562	$ 21,322

Amount of available-for-sale debt securities at fair value maturing in the next fiscal year following the latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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