Net Loss Per Share - Summary of Potential Dilutive Securities Excluded from Calculation of Diluted Per Share (Details) - shares	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	33,013,519	9,201,183
Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	9,010,875	9,131,129
Estimated Shares Issuable Under the ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	110,144	64,758
Restricted Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	0	5,296
Restricted Stock Subject to Future Vesting
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	892,500	0
Common Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti Dilutive Shares	23,000,000	0

Biomea Fusion, Inc. 10-Q