Net Loss Per Share - Summary of Basic and Diluted Net Loss Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Numerator:
Net loss	$ (62,214)	$ (108,483)
Denominator:
Weighted average common stock outstanding - basic	61,857,573	60,136,198
Weighted average common stock outstanding - diluted	61,857,573	60,136,198
Net loss per share - basic	$ (1.01)	$ (1.8)
Net loss per share - diluted	$ (1.01)	$ (1.8)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Sage Therapeutics, Inc. 10-Q