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Term Loan Prepayment During Second Year [Member] Term Loan Prepayment During Second Year [Member] Term Loan Prepayment During Second Year. Antidilutive securities excluded from computation of earnings per share amount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Subsequent Event [Line Items] 2020 Inducement Plan [Member] Two Thousand Twenty Inducement Plan [Member] Two thousand twenty inducement plan. Asset Class Asset Class [Domain] License Agreements License Agreement Disclosure [Text Block] License agreement disclosure. Common Stock [Member] Common Stock [Member] Cash and Cash Equivalents, at Carrying Value, Total Cash and cash equivalents Cash and cash equivalents, end of period Cash and Cash Equivalents, at Carrying Value Restricted cash BioMarin Pharmaceutical Inc [Member] Bio Marin Pharmaceutical Inc [Member] BioMarin Pharmaceutical Inc. 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