Fair Value Measurements - Contingent Consideration (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Reconciliation of contingent consideration obligations related to acquisitions
Adjustments to fair value of contingent consideration	$ 1,043	$ 5,056
Change in fair value of contingent consideration	(1,043)	$ (5,056)
Lumara Health and MuGard Rights \| Fair Value, Measurements, Recurring \| Level 3
Reconciliation of contingent consideration obligations related to acquisitions
Balance at beginning of period	147,995
Payments made	(83)
Adjustments to fair value of contingent consideration	1,043
Balance at end of period	148,955
Change in fair value of contingent consideration	(1,043)
Mekana
Acquired Finite-Lived Intangible Assets [Line Items]
Contingent consideration classified as short-term liability	97,200
Reconciliation of contingent consideration obligations related to acquisitions
Adjustments to fair value of contingent consideration	1,000
Change in fair value of contingent consideration	(1,000)
Milestone payment expected to be paid in 2016 to the former Lumara Health security holders based on achievement of a net sales milestone of Makena	100,000
Estimated undiscounted milestone amounts payable	250,000
MuGard
Acquired Finite-Lived Intangible Assets [Line Items]
Contingent consideration classified as short-term liability	$ 300
Reconciliation of contingent consideration obligations related to acquisitions
Discount rate (as a percent)	12.00%
Period over which estimated undiscounted royalty amounts could be paid (in years)	10 years
MuGard \| Minimum
Reconciliation of contingent consideration obligations related to acquisitions
Estimated undiscounted royalty amounts payable	$ 2,000
MuGard \| Maximum
Reconciliation of contingent consideration obligations related to acquisitions
Estimated undiscounted royalty amounts payable	$ 6,000

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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