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Microsystems, Inc. Allegro Microsystems, Inc. [Member] Allegro Microsystems, Inc. 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Liabilities, and Other Liabilities Disclosure, Current [Text Block] Returns and Sales Allowances Accounts Receivable, Allowance For Returns And Sales [Roll Forward] Accounts Receivable, Allowance For Returns And Sales Completed technology Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Cash paid for operating leases Operating Lease, Payments Net actuarial gain (loss) amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax of $(164), $(472) and $391 in 2023, 2022 and 2021, respectively Net actuarial loss and amortization of net transition obligation and prior service costs related to defined benefit plans, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Volatility Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Additions during the year Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase for Purchase Allowances for doubtful accounts Provision for expected credit losses Balance at the beginning of the period Balance at the end of the period Accounts Receivable, Allowance for Credit Loss, Current Common stock, shares authorized (in shares) Common Stock, Shares Authorized Accrued income taxes Accrued Income Taxes, Current Statement of Comprehensive Income [Abstract] Total operating expenses Operating Expenses Maximum Maximum [Member] Non-Controlling Interests Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block] Conversion of LTCIP/TRIP awards into restricted stock units in connection with the IPO Adjustments To Additional Paid In Capital, Conversion Of Awards Adjustments To Additional Paid In Capital, Conversion Of Awards Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Cash and cash equivalents Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash and Cash Equivalents, at Carrying Value Net (losses) gains recognized during the period on equity securities Equity Securities, FV-NI, Gain (Loss) Business Acquisition [Line Items] Business Acquisition [Line Items] Measurement Frequency [Domain] Measurement Frequency [Domain] Schedule of Expense Related to Defined Benefit Plan Schedule of Net Benefit Costs [Table Text Block] Line of Credit Facility [Table] Line of Credit Facility [Table] In-process research and development Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Indefinite-Lived Intangible Assets AMTC Facility AMTC Facility [Member] AMTC Facility Capitalization changes related to organizational structure of affiliates and direct and indirect interests in subsidiaries Adjustments To Additional Paid In 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currency exchange gains (losses) on equity securities Foreign Currency Transaction Gain (Loss), Unrealized Schedule of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Raw materials and supplies Inventory, Raw Materials and Supplies, Net of Reserves Related Party [Axis] Related Party [Axis] Goodwill [Roll Forward] Goodwill [Roll Forward] Land Land [Member] Incremental common shares (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-Based Payment Arrangements Returns and sales allowances Balance at the beginning of the period Balance at the end of the period Accounts Receivable, Allowance For Returns And Sales, Current Accounts Receivable, Allowance For Returns And Sales, Current Organization, Consolidation and Presentation of Financial Statements [Abstract] Disposal Group Name [Domain] Disposal Group Name [Domain] Acquisition of business, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Level 2 Fair Value, Inputs, Level 2 [Member] Current Fiscal Year End Date Current Fiscal Year End Date Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Intangible assets, net Net Carrying Amount Intangible Assets, Net (Excluding Goodwill) Accrued retirement Liability, Retirement and Postemployment Benefits Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Total current liabilities Liabilities, Current Cash dividends to non-controlling interest Dividends, Cash Schedule of Trade Accounts Receivable, Net Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Customer Concentration Risk Customer Concentration Risk [Member] Other current liabilities Other Sundry Liabilities, Current Entity Ex Transition Period Entity Ex Transition Period AME Plan AME Plan [Member] AME Plan Unrecognized tax benefits that would impact effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Other income (expense): Nonoperating Income (Expense) [Abstract] Unrealized gains on marketable securities Unrealized gains and losses recognized during the reporting period on equity securities still held at the reporting date Equity Securities, FV-NI, Unrealized Gain (Loss) Accounts receivable - other Accounts and Other Receivables, Net, Current FDII Effective Income Tax Rate Reconciliation, FDII, Amount Unrealized gains on marketable securities Unrealized Gain (Loss) on Investments Europe Europe [Member] Fair Value Disclosures [Abstract] Stocks Defined Benefit Plan, Equity Securities, Common Stock [Member] Number of locations Number Of Locations Number Of Locations Credit Facility [Axis] Credit Facility [Axis] Other Asia Other Asia [Member] Other Asia Sales return of resalable inventory Related Party Transaction, Amounts of Transaction Unrealized gains on marketable securities Marketable Securities, Unrealized Gain (Loss) RECONCILIATION OF CASH AND CASH EQUIVALENTS AND RESTRICTED CASH: Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents [Abstract] Company contributions Defined Contribution Plan, Employer Discretionary Contribution Amount Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] Entity Tax Identification Number Entity Tax Identification Number Schedule of Long-lived Assets Long-Lived Assets by Geographic Areas [Table Text Block] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income 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[Domain] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Deferred income tax liabilities: Deferred Income Taxes and Other Liabilities [Abstract] Interest expense Interest Expense Indefinite-lived process technology and trademarks Indefinite-Lived Technology-Based Intangible Assets And Legacy Trademarks [Member] Indefinite-Lived Technology-Based Intangible Assets And Legacy Trademarks Retirement Plan Type [Axis] Retirement Plan Type [Axis] Inventories Inventory Disclosure [Text Block] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Machinery and equipment Machinery and Equipment [Member] Right-of-use asset Deferred Tax Liabilities, Leasing Arrangements Buildings Building [Member] Inventory Disclosure [Abstract] Underfunded status at end of year Defined Benefit Plan, Funded (Unfunded) Status of Plan Grant percentage of target shares granted maximum Share-Based Compensation Arrangement By Share-Based Payment Award, Grant 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