The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Subsequent Event (Details Textual) - USD ($) $ in Thousands		12 Months Ended
Subsequent Event (Details Textual) - USD ($) $ in Thousands	Feb. 28, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Severance costs		$ 776
Revenue		103,269	$ 173,245	$ 150,246
Selling, general and administrative expenses		100,359	58,860	44,179
Research and development expenses		39,329	33,418	34,611
Noctiva
Subsequent Event [Line Items]
Revenue		1,204	0	$ 0
Noctiva \| Specialty Pharma \| Discontinued Operations, Disposed of by Means Other than Sale
Subsequent Event [Line Items]
Revenue		1,204	0
Selling, general and administrative expenses		62,268	13,536
Research and development expenses		$ 2,782	$ 1,688
Subsequent event \| Scenario, Forecast \| Noctiva \| Specialty Pharma
Subsequent Event [Line Items]
Workforce reduction, percentage	50.00%
Subsequent event \| Minimum \| Scenario, Forecast \| Noctiva \| Specialty Pharma
Subsequent Event [Line Items]
Severance costs	$ 10,000
Subsequent event \| Maximum \| Scenario, Forecast \| Noctiva \| Specialty Pharma
Subsequent Event [Line Items]
Severance costs	$ 15,000