Subsequent Events (Details) - Subsequent event $ / shares in Units, $ in Millions	May 09, 2022 USD ($) $ / shares	Apr. 04, 2022 USD ($) shares
Channel
Subsequent Events
Upfront cash payment		$ 35.0
Stock issued in acquisition, number of shares \| shares		493,254
Stock issued in acquisition		$ 65.0
Potential developmental and regulatory milestones on BHV-7000		325.0
Potential developmental and regulatory milestones on Kv7 pipeline development		250.0
Potential commercial sales based milestones of BHV-7000		$ 562.5
Pfizer \| Biohaven
Subsequent Events
Transaction cash consideration	$ 11,600.0
Price per share to be acquired (in dollars per share) \| $ / shares	$ 148.50
Share ratio of new publicly traded company per two shares to existing shareholders	1
New Biohaven
Subsequent Events
Post merger capitalization	$ 275.0
Net sales threshold for tiered royalty rights	$ 5,250.0

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Amount of acquirer's equity interest issued and issuable as part of consideration transferred in asset acquisition.

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