Collaborative Arrangements - Cystic Fibrosis Foundation Therapeutics Incorporated (Details) - Cystic Fibrosis Foundation Therapeutics Incorporated	12 Months Ended
Dec. 31, 2016 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
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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Balance Type:	na
Period Type:	duration