Document and Entity Information Document Type Entity Registrant Name Entity Filer Category Entity Small Business Entity Emerging Growth Company Entity Ex Transition Period Entity Central Index Key Amendment Flag Statement of Financial Position [Abstract] Statement [Table] Related and Nonrelated Parties [Axis] Related and Nonrelated Parties [Domain] Related Party [Member] Legal Entity [Axis] Entity [Domain] Represents information pertaining to Archimedes Tech SPAC Partners II Co. Archimedes Tech SPAC Partners II Co [Member] Archimedes Tech SPAC Partners II Co Statement [Line Items] Current assets Current Assets Cash Cash and cash equivalents Prepaid expenses Prepaid expenses us-gaap_AssetsCurrent Total Current Assets Total current assets Deferred offering costs Prepaid insurance Cash held in Trust Account Asset, Held-in-Trust, Noncurrent us-gaap_Assets TOTAL ASSETS Current liabilities Current Liabilities Accrued expenses Current liabilities - Accrued expenses Amount of accrued offering costs, classified as current. Accrued offering costs Due to related party Accounts payable Promissory note - related party us-gaap_LiabilitiesCurrent Total current liabilities Deferred underwriting fee payable Accounts Payable and Accrued Liabilities, Noncurrent us-gaap_Liabilities TOTAL LIABILITIES Commitments and Contingencies Commitments and contingencies Ordinary shares subject to possible redemption, 23,000,000 shares at redemption value of $10.43 per share as of December 31, 2025 and none at December 31, 2024 Preferred stock, Ending balance Preferred stock, Beginning balance Ordinary shares subject to possible redemption, December 31, 2025 Preferred stock - $0.0001 par value; 4,663,753 and 1,931,849 shares authorized and 1,925,348 and 1,676,528 shares issued and outstanding as of December 31, 2025 and December 31, 2024, respectively. SHAREHOLDERS' DEFICIT Stockholders' Deficit Preference shares, $0.0001 par value; 1,000,000 shares authorized; none issued or outstanding Ordinary shares, $0.0001 par value; 400,000,000 shares authorized; 6,590,000 and 5,750,000 shares issued and outstanding (excluding 23,000,000 and 0 shares subject to possible redemption) as of December 31, 2025 and 2024, respectively Common stock - $0.0001 par value; 4,850,000 and 4,550,000 shares authorized and 1,648,841 and 1,643,081 shares issued and outstanding as of December 31, 2025 and December 31, 2024, respectively. Common stock, $0.0001 par value; 100 shares authorized, issued and outstanding Additional paid-in capital Additional paid-in capital Accumulated deficit Accumulated deficit us-gaap_StockholdersEquity Balance Balance TOTAL SHAREHOLDERS' DEFICIT us-gaap_LiabilitiesAndStockholdersEquity TOTAL LIABILITIES, ORDINARY SHARES SUBJECT TO POSSIBLE REDEMPTION, AND SHAREHOLDERS' DEFICIT Sale of Stock [Axis] Sale of Stock [Domain] IPO [Member] Over-Allotment Option [Member] Ordinary shares subject to possible redemption, shares (in shares) Temporary Equity, Shares Outstanding (in shares) Preferred stock, shares outstanding Ordinary shares subject to possible redemption, redemption value per share (in dollars per share) Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, par value per share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares authorized Common stock, shares issued (in shares) Ending balance (in shares) Beginning balance (in shares) Common Stock, Shares, Issued Common stock, shares issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Common stock, shares outstanding The number of shares of units issued during the period. atiiu_UnitsIssuedDuringPeriodShares Units Issued During Period, Shares (in shares) The number of shares subject to forfeiture. atiiu_SharesSubjectToForfeiture Shares Subject to Forfeiture (in shares) Income Statement [Abstract] Financial Instrument [Axis] Financial Instruments [Domain] Represents the cash in bank account. Cash In Bank Account [Member] Represents the cash held in trust account. Cash Held In Trust Account [Member] Class of Stock [Axis] Class of Stock [Domain] Represents redeemable ordinary shares. Redeemable Ordinary Shares [Member] Represents non-redeemable ordinary shares. Non-redeemable Ordinary Shares [Member] General and administrative expenses General and administrative us-gaap_OperatingIncomeLoss Loss from operations Other income: Nonoperating Income (Expense) Interest earned on cash in bank account Interest earned on cash held in Trust Account Interest income us-gaap_NonoperatingIncomeExpense Total other income Net income (loss) Net Loss Net income (loss) Net income (loss) Basic and diluted weighted average shares outstanding, redeemable ordinary shares (in shares) Weighted-Average Shares Outstanding, Basic Basic weighted-average shares outstanding (in shares) Basic and diluted net income per share, redeemable ordinary shares (in dollars per share) Net Loss Per Share, Basic Basic net income (loss) per ordinary share (in dollars per share) Diluted weighted average shares outstanding, non-redeemable ordinary shares (in shares) Weighted-Average Shares Outstanding, Diluted Diluted weighted-average shares outstanding (in shares) Diluted net income (loss) per share, non-redeemable ordinary shares (in dollars per share) Net Loss Per Share, Diluted Diluted net income (loss) per ordinary share (in dollars per share) Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Component [Domain] Common Stock [Member] Common Stock Additional Paid-in Capital [Member] Additional Paid-In Capital Retained Earnings [Member] Accumulated Deficit us-gaap_SharesOutstanding Balance (in shares) Balance (in shares) Issuance of shares (in shares) Stock Issued During Period, Shares, New Issues (in shares) Shares issued (in shares) Issuance of shares Issuance of common stock Fair value of Public Warrants at issuance us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts Allocated value of transaction costs to warrants and private placement units Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs us-gaap_TemporaryEquityAccretionToRedemptionValue Accretion of ordinary shares subject to possible redemption amount Accretion of carrying value to redemption value Statement of Cash Flows [Abstract] Nonrelated Party [Member] Cash Flows from Operating Activities: Cash Flows from Operating Activities Adjustments to reconcile net income (loss) to net cash used in operating activities: Adjustments to reconcile net loss to net cash used in operations: Amount of general and administrative expenses paid by issuance of shares. General and administrative expenses paid by Sponsor in exchange for issuance of Founder Shares Amount of general and administrative expenses paid by issuance of notes. General and administrative expenses paid through promissory note - related party Changes in operating assets and liabilities: Changes in operating assets and liabilities (used in) provided by cash, cash equivalents, and restricted cash: us-gaap_IncreaseDecreaseInPrepaidExpense Prepaid expenses us-gaap_IncreaseDecreaseInAccruedLiabilities Accrued expenses Accrued expenses Amount of increase (decrease) of consideration paid in advance for insurance that provides economic benefits in future periods. atiiu_IncreaseDecreaseInPrepaidInsuranceNoncurrent Prepaid insurance us-gaap_NetCashProvidedByUsedInOperatingActivities Net cash used in operating activities Cash Flows from Investing Activities: Cash Flows from Investing Activities us-gaap_PaymentsToAcquireRestrictedInvestments Investment of cash in Trust Account us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used in investing activities Cash Flows from Financing Activities: Cash Flows from Financing Activities Proceeds from sale of Units, net of underwriting discounts paid Proceeds from sale of Private Placement Units PIPE capital commitment from a single investor The repayment amounts due to related parties during the period. atiiu_RepaymentsOfDueToRelatedParty Repayment of due to related party Proceeds from promissory note - related party us-gaap_RepaymentsOfRelatedPartyDebt Repayment of promissory note-related party Repayments of Related Party Debt us-gaap_PaymentsOfStockIssuanceCosts Payment of offering costs Ordinary shares issuance costs Payments of Stock Issuance Costs us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash provided by financing activities us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect Net Change in Cash us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations Cash - End of period Cash - Beginning of period Non-Cash investing and financing activities: Supplemental Disclosure of Noncash Investing and Financing Transactions The amount of offering costs that were incurred during a noncash or partial noncash transaction. Offering costs included in accrued offering costs Amount of stock issued to pay deferred offering costs in noncash transaction. Offering costs paid by Sponsor in exchange for the issuance of Founder Shares Offering costs paid through promissory note - related party Amount of deferred underwriting fee payable in noncash transaction. atiiu_DeferredUnderwritingFeePayableInNoncashTransaction Deferred underwriting fee payable Notes To Financial Statements [Abstract] Nature of Operation, Product Information, Concentration of Risk [Table] us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements Business Description and Basis of Presentation [Text Block] Accounting Standards Update and Change in Accounting Principle [Table] Significant Accounting Policies [Text Block] Significant Accounting Policies Subsidiary or Equity Method Investee, Sale of Stock [Table] The entire disclosure of initial public offering. Initial Public Offering [Text Block] The entire disclosure for private placement. Private Placement [Text Block] Related Party Transaction [Table] Related Party Transactions Disclosure [Text Block] Other Commitments [Table] Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies Stock, Class of Stock [Table] Equity [Text Block] STOCKHOLDER'S DEFICIT Schedule of Segment Reporting Information, by Segment [Table] Segment Reporting Disclosure [Text Block] Segment Reporting Subsequent Event [Table] Subsequent Events [Text Block] SUBSEQUENT EVENTS Significant Accounting Policies. atiiu_PolicyTable us-gaap_PolicyTextBlockAbstract Accounting Policies Significant Accounting Policies Basis of Accounting, Policy [Policy Text Block] Basis of Presentation Consolidation, Policy [Policy Text Block] Principles of Consolidation Use of Estimates, Policy [Policy Text Block] Use of Estimates Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Concentration Risk, Credit Risk, Policy [Policy Text Block] Deferred Charges, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Income Taxes Earnings Per Share, Policy [Policy Text Block] Earnings (Loss) Per share Net Loss Per Share Fair Value of Financial Instruments, Policy [Policy Text Block] Fair Value Measurement, Policy [Policy Text Block] Stockholders' Equity, Policy [Policy Text Block] Disclosure for accounting policy for temporary equity. Temporary Equity [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Standards Recent Issued Accounting Pronouncements Not Yet Adopted Note 2 - Summary of Significant Accounting Policies us-gaap_TableTextBlock Notes Tables Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Summary of computation of basic and diluted loss per share Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Summary of inputs and assumptions were used to value the warrants Temporary Equity [Table Text Block] Schedule of temporary equity Note 8 - Segment Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of reconciliations of segment revenues Note To Financial Statement Details Textual Private Placement [Member] PIPE Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] Represents Public Warrants. Public Warrants [Member] Represents Private Placement Warrants. Private Placement Warrants [Member] Counterparty Name [Axis] Counterparty Name [Domain] Represents the underwriters. Underwriters [Member] Nature of Expense [Axis] Interim Period, Costs Not Allocable [Domain] Represents other offering costs. Other Offering Costs [Member] Long-Term Debt, Type [Axis] Long-Term Debt, Type [Domain] Loans Payable [Member] Per unit price of units issued. atiiu_UnitsIssuedPricePerUnit Units Issued, Price Per Unit us-gaap_ProceedsFromIssuanceOrSaleOfEquity Proceeds from Issuance or Sale of Equity The number of ordinary shares per unit. atiiu_UnitsIssuedNumberOfSharesPerUnit Units Issued, Number of Shares Per Unit The number of warrants per unit. atiiu_UnitsIssuedNumberOfWarrantsPerUnit Units Issued, Number of Warrants Per Unit us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight Class of Warrant or Right, Number of Securities Called by Each Warrant or Right us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1 Class of Warrant or Right, Exercise Price of Warrants or Rights Exercise price Percentage of net assets for required business acquisition. atiiu_BusinessAcquisitionRequiredPercentageOfNetAssets Business Acquisition Required, Percentage of Net Assets Percentage of outstanding voting interests for required business acquisition. atiiu_BusinessAcquisitionRequiredPercentageOfOutstandingVotingInterests Business Acquisition Required, Percentage of Outstanding Voting Interests us-gaap_AssetsHeldInTrust Asset, Held-in-Trust Trust account Per unit price of assets held in trust. atiiu_AssetsHeldInTrustPerUnitPrice Assets Held in Trust, Per Unit Price Percentage of shares redeemed if required business acquisition does not occur. atiiu_BusinessAcquisitionRequiredFailurePercentageOfSharesRedeemed Business Acquisition Required, Failure, Percentage of Shares Redeemed Percentage of maximum redemption of shares without consent. atiiu_MaximumRedemptionOfSharesWithoutConsentPercentage Maximum Redemption of Shares Without Consent, Percentage Period from IPO for required business combination. atiiu_BusinessAcquisitionRequiredPeriodFromIPO Business Acquisition Required, Period From IPO Period for redemption of shares if the required business acquisition does not occur. atiiu_BusinessAcquisitionRequiredFailurePeriodForRedemption Business Acquisition Required, Failure, Period for Redemption Maximum amount of interest to pay dissolution expenses if required business acquisition does not occur. atiiu_BusinessAcquisitionRequiredFailureMaximumInterestToPayDissolutionExpenses Business Acquisition Required, Failure, Maximum Interest to Pay Dissolution Expenses us-gaap_Cash Cash Maximum amount of debt that is convertible. atiiu_DebtInstrumentMaximumConvertible Debt Instrument, Maximum Convertible