Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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.

+ References

No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Stock-Based Compensation - Cellectis Equity Incentive Plan - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted			554,243	2,120,347
Stock-based compensation expense			$ 4,385	$ 12,091	$ 948
Cellectis [Member] \| Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value for stock options granted	$ 17.16
Options granted		0
Stock-based compensation expense			$ 100	$ 400	$ 900