Business combination - Pro Forma Impact of Business Combination (Details) - ARIAD Pharmaceuticals - USD ($) $ in Thousands	3 Months Ended	4 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Unaudited pro forma information
Acquisition-Related Costs	$ 1,500			$ 1,500
Revenue of ARIAD			$ 16,700
Net loss of ARIAD			$ (28,200)
Pro forma net sales	269,469	$ 194,866		821,743	$ 528,711
Pro forma net income (loss)	36,877	$ (48,613)		91,248	$ (96,015)
Revenue that had been deferred	$ 24,400			$ 24,400

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. For cash flows, this element primarily pertains to amortization of deferred credits on long-term arrangements. As a noncash item, it is deducted from net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
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-Section S99
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