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Commitments and Contingencies - Major Customers (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 customer | Sep. 30, 2013 customer | Sep. 30, 2014 customer | Sep. 30, 2013 customer
Major Customers |  |  |  |
Number of major customers | 1 | 1 | 1 | 1
Customer one |  |  |  |
Major Customers |  |  |  |
Percentage of revenue to total revenue | 11.30% | 14.70% | 11.70% | 14.30%

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