v3.25.2

Stockholders' Equity - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]
Options Outstanding, Beginning Balance	6,157,532
Options Outstanding, Options granted	4,500,523
Options Outstanding, Options exercised	(9,672)
Options Outstanding, Options cancelled	(974,087)
Options Outstanding, Ending Balance	9,674,296	6,157,532
Options Outstanding, Options exercisable as of June 30, 2025	4,375,667
Options Outstanding, Options vested and expected to vest as of June 30, 2025	9,674,296
Weighted-Average Exercise Price, Beginning Balance	$ 10.29
Weighted-Average Exercise Price, Options granted	5.11
Weighted-Average Exercise Price, Options exercised	8.25
Weighted-Average Exercise Price, Options cancelled	7.35
Weighted-Average Exercise Price, Ending Balance	8.18	$ 10.29
Weighted-Average Exercise Price, Options exercisable as of June 30, 2025	10.80
Weighted-Average Exercise Price, Options vested and expected to vest as of June 30, 2025	$ 8.18
Weighted-Average Remaining Contractual Term	6 years 11 months 19 days	7 years 7 months 2 days
Weighted-Average Remaining Contractual Term, Options exercisable as of June 30, 2025	4 years 7 days
Weighted-Average Remaining Contractual Term, Options vested and expected to vest as of June 30, 2025	6 years 11 months 19 days
Aggregate Intrinsic Value, Balance	$ 25,279	$ 2,133
Aggregate Intrinsic Value, Options exercisable as of June 30, 2025	5,410
Aggregate Intrinsic Value, Options vested and expected to vest as of June 30, 2025	$ 25,279

Share based compensation arrangement by share based payment award stock options exercised and shares vested.

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Share based compensation arrangements by share based payment award options exercises and shares vested in period weighted average exercise price.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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-Topic 718
-SubTopic 10
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-Publisher FASB
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Phathom Pharmaceuticals, Inc. 10-Q