Collaborative Arrangements and Acquisitions - Cystic Fibrosis Foundation Therapeutics Incorporated (Details) - Cystic Fibrosis Foundation Therapeutics Incorporated - USD ($)	3 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2016
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Additional milestone payments	$ 0
Collaborative funding		$ 75,000,000.0
Additional collaborative funding		$ 6,000,000.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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