Basis of Presentation and Principles of Consolidation (Policies)	9 Months Ended
Sep. 30, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The Unaudited Condensed Consolidated Financial Statements of Standard Nuclear, Inc. (the “Company”), which include the accounts of the Company and its wholly-owned subsidiary, Standard Property Holdings I, LLC, as of September 30, 2026, and for the three and nine months ended September 30, 2026 and 2025, have been prepared pursuant to the rules and regulations of the SEC. The accompanying Unaudited Condensed Consolidated Financial Statements have been prepared in accordance with Article 10 of Regulation S-X and, therefore, do not include all information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. The Condensed Consolidated Balance Sheet as of December 31, 2025, was derived from audited Consolidated Financial Statements, but does not include all disclosures required by U.S. GAAP. All material intercompany transactions have been eliminated. The accompanying Condensed Consolidated Financial Statements have been prepared assuming that the Company will continue as a going concern. Historically, the Company has incurred significant losses from operations and negative operating cash flows. Management believes that the Company's current cash on hand, which includes the net proceeds received from its IPO completed in July 2026 (see Note 8 - Stockholders’ Equity), will be sufficient to fund the Company's operations and meet its obligations for at least the twelve months from the date of issuance of these financial statements.
Deferred Transaction Costs	Deferred Transaction Costs Deferred transaction costs consist of specific incremental legal, accounting and other direct third-party costs directly attributable to the Company’s IPO.
Preferred Stock	Preferred Stock Prior to the IPO, the Company's redeemable convertible preferred stock was classified as temporary equity within mezzanine equity in accordance with ASC 480-10-S99-3A, because the shares included liquidation and deemed liquidation features that were not solely within the Company's control, and the carrying amount was adjusted to its redemption value. The Company accounted for preferred stock in accordance with ASC 480, Distinguishing Liabilities from Equity, and ASC 815-40, Derivatives and Hedging — Contracts in an Entity’s Own Equity. At issuance, the Company evaluated the terms of each preferred stock instrument to determine whether it should be classified as a liability, temporary equity, or permanent equity. In performing this assessment, the Company considered all relevant contractual terms, including redemption rights, conversion features, dividend provisions, and settlement alternatives. The redeemable convertible preferred stock was not classified as a liability because it did not embody an unconditional obligation requiring the Company to redeem the shares for cash or other assets, nor did it require settlement in a variable number of shares with a fixed monetary value. Refer to Note 7 — Redeemable Preferred Stock for additional information.
Share Based Compensation	Share Based Compensation The Company grants stock options, RSAs, and RSUs, and recognizes the related expense on a straight-line basis over the requisite service period. The fair value of RSAs and RSUs is based on the fair value of the Company's common stock on the date of grant. The Company estimates the fair value of stock options on the date of grant using the Black-Scholes option pricing model. This model requires the use of subjective assumptions, including the expected term of the award, expected stock price volatility, risk-free interest rate, and expected dividend yield. The expected term represents the period that the stock options are expected to be outstanding. As the Company does not have sufficient historical exercise data, it estimates the expected term using the simplified method, which is the midpoint between the vesting term and the contractual term of the option, in accordance with SEC Staff Accounting Bulletin No. 107 and No. 110. The expected stock price volatility is based on the historical volatility of a group of comparable publicly traded companies, as the Company does not have sufficient trading history for its own common stock. The risk-free interest rate is based on the yield of U.S. Treasury securities with maturities consistent with the expected term of the stock options. The expected dividend yield is assumed to be zero, as the Company has not historically paid dividends and does not currently expect to pay dividends in the foreseeable future. The Company has elected to account for forfeitures as they occur. As a result, share-based compensation expense is recognized for awards expected to vest, and adjustments are made in the period of forfeiture to reverse previously recognized expense for awards that do not vest.
Loss Per Share	Loss Per Share The Company computes net loss per share attributable to common stockholders in accordance with ASC 260, Earnings Per Share. Net loss per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. The Company has two classes of common stock outstanding, Class A common stock and Class B common stock. Except for voting rights and conversion provisions, the rights of the two classes, including dividend and liquidation rights, are identical. Accordingly, net loss per share is the same for each class, and the Company presents basic and diluted net loss per share for both classes together. Immediately prior to the closing of the IPO on July 17, 2026, all outstanding shares of redeemable convertible preferred stock converted into shares of Class A common stock. These shares are included in the weighted-average number of shares outstanding from the date of conversion, together with the shares issued in the IPO and in connection with the Class B Conversion and the Class B Stock Exchange from their respective dates. Following the IPO, potentially dilutive securities also include RSUs. Net loss attributable to common stockholders is determined by adjusting net loss for dividends declared or accumulated on preferred stock and, if applicable, accretion or other adjustments to the carrying amount of redeemable convertible preferred stock that are treated as deemed dividends. Redeemable convertible preferred stock is excluded from basic net loss per share until converted. Diluted net income (loss) per share attributable to common stockholders gives effect to all potentially dilutive common shares outstanding during the period. Potentially dilutive securities include stock options, unvested RSAs and RSUs, and shares issuable upon conversion of redeemable convertible preferred stock. Stock options and other awards are included in diluted net income (loss) per share using the treasury stock method, and redeemable convertible preferred stock is included using the if-converted method. Under the if-converted method, preferred dividends and deemed dividends, if any, applicable to the redeemable convertible preferred stock are added back to the numerator and the weighted-average shares issuable upon conversion are included in the denominator, if dilutive. Potentially dilutive securities are excluded from the computation of diluted net income (loss) per share if their effect would be anti-dilutive.
Accounting Pronouncements Recently Issued or Adopted	Accounting Pronouncements Recently Issued or Adopted In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses (“ASU 2024-03”). ASU 2024-03 requires additional footnote disclosure of the details of certain income statement expense line items as well as additional disclosure about selling expenses. This standard is effective for fiscal years beginning after December 15, 2026, and early adoption is permitted. The guidance is to be applied prospectively, with the option for retrospective application. The Company is currently evaluating the impact the adoption of this standard will have on its disclosures.
Revenue Recognition	The Company recognizes revenue at a point in time or over time consistent with how it satisfies its performance obligations and transfers control to its customers. The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers, when control of promised goods or services transfers to the customer in an amount reflecting the consideration the Company expects to receive. The Company's revenue recognition policies are consistent with those described in Note 2, Summary of Significant Accounting Policies, to the audited consolidated financial statements included in the Company's Registration Statement, except as described below with respect to product revenue, which the Company began recognizing during the second quarter of 2026. Services Revenue The Company provides fuel development, engineering, testing, and other technical services under contracts structured as time-and-materials or fixed-price, milestone-based arrangements. These services are typically accounted for as a single performance obligation satisfied over time. The Company measures progress using a cost-to-cost input method, except for time-and-materials arrangements, for which it applies the right-to-invoice practical expedient under ASC 606-10-55-18. Product Revenue The Company also generates revenue from the sale of TRISO fuel and related products under contracts that represent distinct performance obligations satisfied at a point in time. The Company recognizes revenue from product sales at the point in time at which control of the product transfers to the customer, which generally occurs upon shipment or delivery of the product to the customer, or over time as the product is produced, in accordance with the terms specified in the applicable customer contract. A receivable is recorded when the Company has an unconditional right to receive payment based on the satisfaction of performance obligations. The Company’s contract assets are recorded when revenue has been recognized for performance obligations for which the Company does not yet have an unconditional right to payment because contractual billing conditions remain unsatisfied.
Allowance for Credit Losses	The Company accounts for expected credit losses on financial assets in accordance with ASC 326, Financial Instruments — Credit Losses. The Company’s methodology for estimating expected credit losses is consistent with that described in the audited Consolidated Financial Statements annual financial statements for the year ended December 31, 2025 included in the Registration Statement. In developing its estimate, the Company considers historical credit loss experience, the aging of receivables, customer-specific facts and circumstances, current economic conditions, and reasonable and supportable forecasts of future collectability.
Fair Value Measurements	The fair value of the Company’s assets and liabilities, which qualify as financial instruments under ASC 820, Fair Value Measurement, approximates the carrying amounts represented in the Consolidated Balance Sheets, primarily due to their short-term nature. Fair value is defined as the price that would be received for sale of an asset or paid for transfer of liability in an orderly transaction between market participants at the measurement date. GAAP establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). These tiers include: •Level 1, defined as observable inputs such as quoted prices (unadjusted) for identical instruments in active markets; •Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable such as quoted prices for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active; and •Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions, such as valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and consideration of factors specific to the asset or liability. Changes in assumptions or in market conditions could significantly affect the estimates. The Company determines whether transfers have occurred between levels in the fair value hierarchy by reassessing the inputs used in determining fair value at the end of each reporting period.

Basis of Presentation and Principles of Consolidation (Policies)

9 Months Ended

Sep. 30, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The Unaudited Condensed Consolidated Financial Statements of Standard Nuclear, Inc. (the “Company”), which include the accounts of the Company and its wholly-owned subsidiary, Standard Property Holdings I, LLC, as of September 30, 2026, and for the three and nine months ended September 30, 2026 and 2025, have been prepared pursuant to the rules and regulations of the SEC. The accompanying Unaudited Condensed Consolidated Financial Statements have been prepared in accordance with Article 10 of Regulation S-X and, therefore, do not include all information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments considered necessary for a fair presentation have been included. The Condensed Consolidated Balance Sheet as of December 31, 2025, was derived from audited Consolidated Financial Statements, but does not include all disclosures required by U.S. GAAP. All material intercompany transactions have been eliminated. The accompanying Condensed Consolidated Financial Statements have been prepared assuming that the Company will continue as a going concern. Historically, the Company has incurred significant losses from operations and negative operating cash flows. Management believes that the Company's current cash on hand, which includes the net proceeds received from its IPO completed in July 2026 (see Note 8 - Stockholders’ Equity), will be sufficient to fund the Company's operations and meet its obligations for at least the twelve months from the date of issuance of these financial statements.

Deferred Transaction Costs

Deferred transaction costs consist of specific incremental legal, accounting and other direct third-party costs directly attributable to the Company’s IPO.

Preferred Stock

Prior to the IPO, the Company's redeemable convertible preferred stock was classified as temporary equity within mezzanine equity in accordance with ASC 480-10-S99-3A, because the shares included liquidation and deemed liquidation features that were not solely within the Company's control, and the carrying amount was adjusted to its redemption value. The Company accounted for preferred stock in accordance with ASC 480, Distinguishing Liabilities from Equity, and ASC 815-40, Derivatives and Hedging — Contracts in an Entity’s Own Equity. At issuance, the Company evaluated the terms of each preferred stock instrument to determine whether it should be classified as a liability, temporary equity, or permanent equity. In performing this assessment, the Company considered all relevant contractual terms, including redemption rights, conversion features, dividend provisions, and settlement alternatives.

The redeemable convertible preferred stock was not classified as a liability because it did not embody an unconditional obligation requiring the Company to redeem the shares for cash or other assets, nor did it require settlement in a variable number of shares with a fixed monetary value. Refer to Note 7 — Redeemable Preferred Stock for additional information.

Share Based Compensation

The Company grants stock options, RSAs, and RSUs, and recognizes the related expense on a straight-line basis over the requisite service period. The fair value of RSAs and RSUs is based on the fair value of the Company's common stock on the date of grant.

The Company estimates the fair value of stock options on the date of grant using the Black-Scholes option pricing model. This model requires the use of subjective assumptions, including the expected term of the award, expected stock price volatility, risk-free interest rate, and expected dividend yield. The expected term represents the period that the stock options are expected to be outstanding. As the Company does not have sufficient historical exercise data, it estimates the expected term using the simplified method, which is the midpoint between the vesting term and the contractual term of the option, in accordance with SEC Staff Accounting Bulletin No. 107 and No. 110. The expected stock price volatility is based on the historical volatility of a group of comparable publicly traded companies, as the Company does not have sufficient trading history for its own common stock. The risk-free interest rate is based on the yield of U.S. Treasury securities with maturities consistent with the expected term of the stock options. The expected dividend yield is assumed to be zero, as the Company has not historically paid dividends and does not currently expect to pay dividends in the foreseeable future.

The Company has elected to account for forfeitures as they occur. As a result, share-based compensation expense is recognized for awards expected to vest, and adjustments are made in the period of forfeiture to reverse previously recognized expense for awards that do not vest.

Loss Per Share

The Company computes net loss per share attributable to common stockholders in accordance with ASC 260, Earnings Per Share. Net loss per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period.

The Company has two classes of common stock outstanding, Class A common stock and Class B common stock. Except for voting rights and conversion provisions, the rights of the two classes, including dividend and liquidation rights, are identical. Accordingly, net loss per share is the same for each class, and the Company presents basic and diluted net loss per share for both classes together.

Immediately prior to the closing of the IPO on July 17, 2026, all outstanding shares of redeemable convertible preferred stock converted into shares of Class A common stock. These shares are included in the weighted-average number of shares outstanding from the date of conversion, together with the shares issued in the IPO and in connection with the Class B Conversion and the Class B Stock Exchange from their respective dates. Following the IPO, potentially dilutive securities also include RSUs.

Net loss attributable to common stockholders is determined by adjusting net loss for dividends declared or accumulated on preferred stock and, if applicable, accretion or other adjustments to the carrying amount of redeemable convertible preferred stock that are treated as deemed dividends. Redeemable convertible preferred stock is excluded from basic net loss per share until converted. Diluted net income (loss) per share attributable to common stockholders gives effect to all potentially dilutive common shares outstanding during the period. Potentially dilutive securities include stock options, unvested RSAs and RSUs, and shares issuable upon conversion of redeemable convertible preferred stock. Stock options and other awards are included in diluted net income (loss) per share using the treasury stock method, and redeemable convertible preferred stock is included using the if-converted method. Under the if-converted method, preferred dividends and deemed dividends, if any, applicable to the redeemable convertible preferred stock are added back to the numerator and the weighted-average shares issuable upon conversion are included in the denominator, if dilutive. Potentially dilutive securities are excluded from the computation of diluted net income (loss) per share if their effect would be anti-dilutive.

Accounting Pronouncements Recently Issued or Adopted

In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses (“ASU 2024-03”). ASU 2024-03 requires additional footnote disclosure of the details of certain income statement expense line items as well as additional disclosure about selling expenses. This standard is effective for fiscal years beginning after December 15, 2026, and early adoption is permitted. The guidance is to be applied prospectively, with the option for retrospective application. The Company is currently evaluating the impact the adoption of this standard will have on its disclosures.

Revenue Recognition

The Company recognizes revenue at a point in time or over time consistent with how it satisfies its performance obligations and transfers control to its customers.

The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers, when control of promised goods or services transfers to the customer in an amount reflecting the consideration the Company expects to receive. The Company's revenue recognition policies are consistent with those described in Note 2, Summary of Significant Accounting Policies, to the audited consolidated financial statements included in the Company's Registration Statement, except as described below with respect to product revenue, which the Company began recognizing during the second quarter of 2026.

Services Revenue

The Company provides fuel development, engineering, testing, and other technical services under contracts structured as time-and-materials or fixed-price, milestone-based arrangements. These services are typically accounted for as a single performance obligation satisfied over time. The Company measures progress using a cost-to-cost input method, except for time-and-materials arrangements, for which it applies the right-to-invoice practical expedient under ASC 606-10-55-18.

Product Revenue

The Company also generates revenue from the sale of TRISO fuel and related products under contracts that represent distinct performance obligations satisfied at a point in time. The Company recognizes revenue from product sales at the point in time at which control of the product transfers to the customer, which generally occurs upon shipment or delivery of the product to the customer, or over time as the product is produced, in accordance with the terms specified in the applicable customer contract.

A receivable is recorded when the Company has an unconditional right to receive payment based on the satisfaction of performance obligations. The Company’s contract assets are recorded when revenue has been recognized for performance obligations for which the Company does not yet have an unconditional right to payment because contractual billing conditions remain unsatisfied.

Allowance for Credit Losses

The Company accounts for expected credit losses on financial assets in accordance with ASC 326, Financial Instruments — Credit Losses. The Company’s methodology for estimating expected credit losses is consistent with that described in the audited Consolidated Financial Statements annual financial statements for the year ended December 31, 2025 included in the Registration Statement. In developing its estimate, the Company considers historical credit loss experience, the aging of receivables, customer-specific facts and circumstances, current economic conditions, and reasonable and supportable forecasts of future collectability.

Fair Value Measurements

The fair value of the Company’s assets and liabilities, which qualify as financial instruments under ASC 820, Fair Value Measurement, approximates the carrying amounts represented in the Consolidated Balance Sheets, primarily due to their short-term nature.

Fair value is defined as the price that would be received for sale of an asset or paid for transfer of liability in an orderly transaction between market participants at the measurement date. GAAP establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). These tiers include:

•Level 1, defined as observable inputs such as quoted prices (unadjusted) for identical instruments in active markets;

•Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable such as quoted prices for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active; and

•Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions, such as valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.

In some circumstances, the inputs used to measure fair value might be categorized within different levels of the fair value hierarchy. In those instances, the fair value measurement is categorized in its entirety in the fair value hierarchy based on the lowest level input that is significant to the fair value measurement. The Company’s assessment of the significance of a particular input to the fair value measurement requires judgment and consideration of factors specific to the asset or liability. Changes in assumptions or in market conditions could significantly affect the estimates. The Company determines whether transfers have occurred between levels in the fair value hierarchy by reassessing the inputs used in determining fair value at the end of each reporting period.