Debt Liability related to sale of future royalties, Narrative (Details) - Royalty Arrangement [Member] - Rpi Finance Trust - USD ($)		6 Months Ended
	Jan. 07, 2018	Jun. 30, 2018
Deferred Revenue Arrangement [Line Items]
Collaborative arrangement purchase price	$ 175,000,000
Collaborative Arrangement Royalty Rate as Percentage of Net Sales	4.15%
Collaborative Arrangement Maximum Royalty Amount	$ 2,000,000,000.0
Collaborative Arrangement Royalty Rate as Percentage of Excess of Global Annual Sales Threshold Limit	1.75%
Collaborative Arrangement Excess of Global Annual Sales Threshold Limit	$ 6,000,000,000.0
Annual interest rate in calculating liability related to sale of future royalties	19.00%
Non-cash interest expenses		$ 19,791,000
Private placement
Deferred Revenue Arrangement [Line Items]
Agreement purchase shares of common stock (in shares)	4,373,178
Share price (in USD per share)	$ 17.15
Sale of stock, consideration received on transaction	$ 75,000,000