Number of stock options exchanged for existing options.

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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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

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Balance Type:	debit
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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ 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

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(01)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Data Type:	xbrli:sharesItemType
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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Description of terms of award under share-based payment arrangement.

+ References

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

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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

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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

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.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Per share decrease in exercise price of option. Excludes change due to standard antidilution provision and option granted under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

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Stock-Based Compensation - Additional information (Details) - USD ($) $ / shares in Units, $ in Millions				9 Months Ended	12 Months Ended
	Aug. 30, 2024	Aug. 26, 2024	Aug. 25, 2024	Sep. 30, 2025	Dec. 31, 2024
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based payment arrangement, nonvested award, option, cost not yet recognized, amount					$ 1.1
Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition					2 years 3 months 18 days
Common stock reserved for future issuance	50,000,000				50,000,000
Share-based compensation arrangement by share-based payment award, number of shares available for grant	50,000,000
Share-based compensation arrangement by share-based payment award, fair value assumptions, exercise price	$ 1.26
Term of options (in years)	10 years
Share-based compensation arrangement by share-based payment award, terms of award	vest 1/48th on a monthly basis over a period of four years from the vesting commencement date as set forth in the applicable option agreement
Two Thousand Twenty Four Stock Option Plan [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Common stock reserved for future issuance	40,000,000
Share-based compensation arrangement by share-based payment award, options, grants in period, gross	40,000,000			50,000,000
Share-based compensation arrangements by share-based payment award, options, grants in period, weighted average exercise price	$ 1.58
Share-based compensation arrangement by share-pased payment award, options, exercisable, weighted average remaining contractual term	10 years			8 years 10 months 24 days
Number of stock options exchanged for existing options	50,000,000
Stock option, exercise price, decrease	$ 1.26
Share-based compensation arrangement by share-based payment award, options, outstanding, intrinsic value	$ 886.8
Share-Based Payment Arrangement [Member] \| 450W42ND MIMA LLC [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation arrangement by share-based payment award, terms of award			the Company agreed to issue to 450W42ND MIMA, LLC, the lower of (a) 4.0 million shares or (b) 2% of the outstanding shares, in each case, of common stock of New Semnur
Share-Based Payment Arrangement [Member] \| Wise Orient Investments Limited [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation arrangement by share-based payment award, terms of award		the Company agreed to issue to Wise Orient Investments Limited, the lower of (a) 4.0 million shares or (b) 2% of the outstanding shares, in each case, of common stock of New Semnur following the consummation of the Business Combination.