Subsequent events - Additional Information (Details) - Subsequent Event - Alexion Pharmaceuticals, Inc. and Odyssey Merger Sub Inc. $ / shares in Units, $ in Millions	May 05, 2020 USD ($) $ / shares
Subsequent Event [Line Items]
Price per share of shares purchased (in dollars per share) \| $ / shares	$ 18.00
Termination fee \| $	$ 51.5

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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Balance Type:	na
Period Type:	duration