Summary Of Significant Accounting Policies (Policy)	6 Months Ended
Summary Of Significant Accounting Policies (Policy)	Mar. 27, 2026
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The unaudited interim condensed consolidated financial statements include the accounts of Dolby Laboratories, Inc. and our wholly-owned and majority-owned subsidiaries. In addition, we have consolidated the financial results of jointly owned affiliated companies in which our principal stockholder or other entities have a noncontrolling interest. We report these noncontrolling interests as a separate line in our unaudited interim condensed consolidated statements of operations as net income attributable to noncontrolling interest and in our unaudited interim condensed consolidated balance sheets as a noncontrolling interest. We eliminate all intercompany accounts and transactions upon consolidation.
Operating Segments
Use of Estimates	Use of Estimates The preparation of our financial statements in accordance with U.S. GAAP requires management to make certain estimates and assumptions that affect the amounts reported and disclosed in our unaudited interim condensed consolidated financial statements and accompanying notes. Significant items subject to such estimates and assumptions include estimated shipments by our licensees for which we are owed a sales-based royalty. These estimates involve the use of historical data and judgment for several key attributes including industry estimates of expected shipments, the percentage of markets using our technologies, and average sale prices. Our estimates of royalty-based revenue also take into consideration the macroeconomic effect of global events that may impact our licensees' supply chain activities as well as demand for shipments. Additional significant items subject to such estimates and assumptions include ESPs for performance obligations within revenue arrangements; allowance for credit losses for accounts receivable; carrying values of inventories and certain PP&E, goodwill, and intangible assets; fair values of investments; accrued liabilities including unrecognized tax benefits, deferred income tax assets and liabilities, and contingent liabilities; and stock-based compensation. Actual results could differ from our estimates. Change in Presentation During fiscal 2025, we changed the presentation of our share of net income from equity method investees and cash distributions from equity method investees within the unaudited interim condensed consolidated statements of cash flows. Our share of net income from equity method investees, previously presented in "other non-cash items affecting net income," and cash distributions from our equity method investees, previously presented within "changes in operating assets and liabilities," are now presented in "share of net income of equity method investees, net of cash distributions." As such, prior period amounts have been reclassified to conform to current period presentation. These reclassifications had no impact on total net cash provided by operating activities.
Fiscal Year	Fiscal Year Our fiscal year is a 52 or 53 week period ending on the last Friday in September. The fiscal periods presented herein include the 13 week period ended March 27, 2026 and March 28, 2025. Our fiscal years ending September 25, 2026 (fiscal 2026) and September 26, 2025 (fiscal 2025) each consist of 52 weeks.
Concentration of Credit Risk	Concentration of Credit Risk Our financial instruments that are exposed to concentrations of credit risk principally consist of cash, cash equivalents, restricted cash, investments, accounts receivable, and contract assets. We maintain cash, cash equivalents, and investments with multiple financial institutions that have high credit standing, and that we believe are financially sound and have minimal credit risk exposure, although at times our balances may exceed the applicable insurance coverage limits. We monitor and manage the overall counterparty credit risk exposure of our cash balances to individual financial institutions on an ongoing basis. Our investment portfolio may consist of investment-grade securities diversified amongst security types, industries, and issuers. All of our securities are held in custody by large national financial institutions. Our investment policy limits the amount of credit exposure to a maximum of 5% of our total portfolio to any one issuer, except for the U.S. Treasury, and we believe no significant concentration risk exists with respect to these investments. We also mitigate counterparty risk through entering into derivative contracts with high-credit-quality financial institutions. Actual or potential defaults of one or more financial institutions could impact our results of operations or financial position, and make it challenging to find alternative qualified counterparties. The majority of our licensing revenue is generated from customers outside of the United States ("U.S."). We manage the credit risk posed by non-U.S. customers by performing regular evaluations of the creditworthiness of our licensing customers and recognize revenue in accordance with U.S. GAAP.
Recently Issued Accounting Policies	Recently Issued Accounting Standards Standards Not Yet Effective Income Taxes. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires further enhancement of income tax disclosures, primarily through standardization and disaggregation of rate reconciliation categories and income taxes paid by jurisdiction. This ASU will be effective for our annual period beginning September 27, 2025, and requires prospective application with the option to apply the standard retrospectively. We will begin including the enhanced income tax disclosures on a prospective basis within the Form 10-K for the year ended September 25, 2026, but do not expect the standard’s adoption to have a material impact on the consolidated financial statement. Income Statement. In November 2024, the FASB issued ASU 2024-03, Income Statement — Reporting Comprehensive Income — Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, which requires public companies to disclose, in interim and annual reporting periods, additional information about certain expenses in notes to financial statements, including purchases of inventory, employee compensation, depreciation, amortization of intangible assets, and selling expenses. In January 2025, the FASB issued ASU 2025-01, Income Statement — Reporting Comprehensive Income — Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date, which clarified the effective date of ASU 2024-03. This standard will be effective for Dolby's annual period beginning September 25, 2027 and interim periods beginning September 30, 2028, with early adoption permitted. We are currently in the process of evaluating the impact of the standard's adoption on our consolidated financial statements and related disclosures. Intangibles. In September 2025, the FASB issued ASU 2025-06, Intangibles — Goodwill and Other — Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software, which eliminates references to the previous stage-based model, and requires capitalization of software costs when management has committed to the software project and it is probable the software will be completed and perform its intended use. This standard is effective for Dolby beginning September 30, 2028, and may be applied prospectively, retrospectively, or using a modified transition approach, with early adoption permitted. We are currently in the process of evaluating the impact of the standard's adoption on our consolidated financial statements and related disclosures.

Disclosure of accounting policy for segment reporting.

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+ Details

- Definition

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

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+ Details

Dolby Laboratories, Inc. 10-Q