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Segment Information - Schedule of revenue by major customers (Details) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
McKesson Corp [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenues | 23.00% | 22.00% | 24.00%
AmerisourceBergen Corp [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenues | 20.00% | 18.00% | 19.00%
Cardinal Health Inc [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenues | 19.00% | 16.00% | 15.00%
Minimum [Member] |  |  |
Revenue, Major Customer [Line Items] |  |  |
Percentage of revenues | 10.00% |  |

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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