Subsequent Event - Additional Information (Detail) - Sarepta Therapeutics - Subsequent Event $ in Millions	Jul. 17, 2017 USD ($)
Subsequent Event [Line Items]
Litigation Settlement, Amount	$ 35.0
United States
Subsequent Event [Line Items]
Royalties receivable percentage of net sales	5.00%
EU and Other Countries
Subsequent Event [Line Items]
Royalties receivable percentage of net sales	8.00%

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Period Type:	duration