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Segment Information Segment Information (Narrative) (Details) | 12 Months Ended
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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 top 3 customers + References No definition available. + Details
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