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Segment Information (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenue by Geographic Area, Major Customers and Segment Information
Upper limit of intersegment sales between the reportable segments	$ 0.1	$ 0.1	$ 0.1

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- Definition

Intersegment Sales Between The Reportable Segments

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No definition available.

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