Fair Value Measurements (Details Textual) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Dec. 31, 2011
Short Term Investments Fair Value	$ 0	$ 2.0
Fair Value Measurements Valuation Techniques	Level 2 valuation technique

Description of the inputs and valuation technique(s) used to measure fair value.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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