Fair Value Measurements (Contractual Maturities Of Available For Sale Investments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Fair Value Disclosures [Abstract]
Maturing in one year or less	$ 7,284	$ 5,164
Maturing after one year through three years	8,000	12,134
Maturing after three years	6,742	4,024
Total debt securities	$ 22,026	$ 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 50

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

-Publisher FASB

-Name Accounting Standards Codification

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

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-Name Accounting Standards Codification

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