Share-Based Compensation - Non-Cash Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-Based Compensation
Non-cash share-based compensation expense	$ 14,565	$ 9,971	$ 43,206	$ 34,855
Less: Share-based compensation expense attributable to non-controlling interests	(1,439)	0	(1,439)	0
Share-based compensation expense attributable to Biohaven Pharmaceutical Holding Company Ltd.	13,126	9,971	$ 41,767	34,855
Minimum
Share-Based Compensation
Requisite service period of award (in years)			3 years
Maximum
Share-Based Compensation
Requisite service period of award (in years)			4 years
Research and development expenses
Share-Based Compensation
Non-cash share-based compensation expense	5,250	3,638	$ 17,927	17,668
Selling, general and administrative expense
Share-Based Compensation
Non-cash share-based compensation expense	$ 9,315	$ 6,333	$ 25,279	$ 17,187

Share-Based Compensation, Attributable To Noncontrolling Interest

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- Definition

Share-Based Compensation, Attributable To Parent

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- Definition

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.

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- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
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