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Segment Information Segment Information (Narrative) (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting [Abstract]
Revenue from top 10 customers	69.00%
Revenue from top 3 customers	37.00%
Revenue from first customer over 10 percent	20.00%	20.00%
Revenue from second customer over 10 percent		15.00%	15.00%

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- Definition

Revenue from first customer over 10 percent

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Revenue from second customer over 10 percent

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Revenue from top 10 customers

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Revenue from top 3 customers

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