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Summary of Significant Accounting Policies - Schedule of Concentration (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Janssen | Accounts Receivable | Credit Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage	29.00%	27.00%	31.00%
Janssen | Revenues Net | Customer Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage	28.00%	29.00%	33.00%
Biogen | Revenues Net | Customer Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage	17.00%	10.00%
Cardinal Health | Accounts Receivable | Credit Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage	12.00%
Cardinal Health | Revenues Net | Customer Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage		13.00%
AmerisourceBergen | Accounts Receivable | Credit Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage	10.00%
Acorda | Accounts Receivable | Credit Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage		15.00%	14.00%
Acorda | Revenues Net | Customer Concentration Risk
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Concentration risk percentage		10.00%	13.00%

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