Sale of Zohydro ER business - Net Gain on Sale (Details) - Zohydro ER [Member] - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Apr. 24, 2015	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration received	$ 93,965
Carrying value of assets transferred to Ferrimill	(2,515)	$ (208)	$ (208)	$ (9,869)
Transaction costs	1,966
Net gain on sale of business before income tax	89,484		$ 89,484	$ 0	$ 0
Income tax expense	14,060	$ 385
Net gain on sale of business	$ 75,424