Basis Of Presentation (Policy)	6 Months Ended
Mar. 30, 2012
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Unaudited Interim Financial Statements	Unaudited Interim Financial Statements We have prepared the accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. (“GAAP”), and with Securities and Exchange Commission (“SEC”) rules and regulations, which allow for certain information and footnote disclosures that are normally included in annual financial statements prepared in accordance with GAAP to be condensed or omitted. In our opinion, these condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements for the fiscal year ended September 30, 2011 and include all adjustments necessary for fair presentation. The accompanying condensed consolidated financial statements should be read in conjunction with our consolidated financial statements for the fiscal year ended September 30, 2011, which are included in our Annual Report on Form 10-K, as amended, filed with the SEC. The results for the fiscal quarter and fiscal year-to-date period ended March 30, 2012 are not necessarily indicative of the results to be expected for any subsequent quarterly or annual financial period, including the fiscal year ending September 28, 2012. P
Principles Of Consolidation	Principles of Consolidation The condensed consolidated financial statements include the accounts of Dolby Laboratories and our wholly owned subsidiaries. In addition, we have consolidated the financial results of jointly owned affiliated companies in which our principal stockholder has a controlling interest. We report these controlling interests as a separate line item in our condensed consolidated statements of operations as net income attributable to controlling interest and in our condensed consolidated balance sheets as controlling interest. We eliminate all intercompany accounts and transactions upon consolidation.
Use Of Estimates	Use of Estimates The preparation of the consolidated financial statements in accordance with GAAP requires management to make certain estimates and assumptions that affect the amounts reported and disclosed in our consolidated financial statements and accompanying notes. Significant items subject to such estimates and assumptions include estimated selling prices for elements sold in multiple-element revenue arrangements, valuation allowances for accounts receivable, carrying values of inventories and certain property, plant and equipment, goodwill, intangible assets, stock-based compensation, fair values of investments, accrued expenses, including liabilities for unrecognized tax benefits, and deferred income tax assets. Actual results could differ from our estimates.
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 periods ended April 1, 2011 and March 30, 2012, and the 27 week period ended April 1, 2011 and the 26 week period ended March 30, 2012. Our fiscal year ended September 30, 2011 (fiscal 2011) consisted of 53 weeks, while our fiscal year ending September 28, 2012 (fiscal 2012) consists of 52 weeks.
Reclassifications	Reclassifications We have reclassified certain prior period amounts within our condensed consolidated financial statements and accompanying notes to conform to our current period presentation. These reclassifications did not affect total revenue, operating income, or net income.

Basis Of Presentation (Policy)

6 Months Ended

Mar. 30, 2012

Organization, Consolidation and Presentation of Financial Statements [Abstract]

We have prepared the accompanying unaudited condensed consolidated financial statements in accordance with accounting principles generally accepted in the U.S. (“GAAP”), and with Securities and Exchange Commission (“SEC”) rules and regulations, which allow for certain information and footnote disclosures that are normally included in annual financial statements prepared in accordance with GAAP to be condensed or omitted. In our opinion, these condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements for the fiscal year ended September 30, 2011 and include all adjustments necessary for fair presentation. The accompanying condensed consolidated financial statements should be read in conjunction with our consolidated financial statements for the fiscal year ended September 30, 2011, which are included in our Annual Report on Form 10-K, as amended, filed with the SEC.

The results for the fiscal quarter and fiscal year-to-date period ended March 30, 2012 are not necessarily indicative of the results to be expected for any subsequent quarterly or annual financial period, including the fiscal year ending September 28, 2012.

Principles Of Consolidation

Principles of Consolidation

The condensed consolidated financial statements include the accounts of Dolby Laboratories and our wholly owned subsidiaries. In addition, we have consolidated the financial results of jointly owned affiliated companies in which our principal stockholder has a controlling interest. We report these controlling interests as a separate line item in our condensed consolidated statements of operations as net income attributable to controlling interest and in our condensed consolidated balance sheets as controlling interest. We eliminate all intercompany accounts and transactions upon consolidation.

Use Of Estimates

Use of Estimates

The preparation of the consolidated financial statements in accordance with GAAP requires management to make certain estimates and assumptions that affect the amounts reported and disclosed in our consolidated financial statements and accompanying notes. Significant items subject to such estimates and assumptions include estimated selling prices for elements sold in multiple-element revenue arrangements, valuation allowances for accounts receivable, carrying values of inventories and certain property, plant and equipment, goodwill, intangible assets, stock-based compensation, fair values of investments, accrued expenses, including liabilities for unrecognized tax benefits, and deferred income tax assets. Actual results could differ from our estimates.

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 periods ended April 1, 2011 and March 30, 2012, and the 27 week period ended April 1, 2011 and the 26 week period ended March 30, 2012. Our fiscal year ended September 30, 2011 (fiscal 2011) consisted of 53 weeks, while our fiscal year ending September 28, 2012 (fiscal 2012) consists of 52 weeks.

Reclassifications

We have reclassified certain prior period amounts within our condensed consolidated financial statements and accompanying notes to conform to our current period presentation. These reclassifications did not affect total revenue, operating income, or net income.

- Definition

Disclosure of accounting policy regarding (1) the principles it follows in consolidating or combining the separate financial statements, including the principles followed in determining the inclusion or exclusion of subsidiaries or other entities in the consolidated or combined financial statements and (2) its treatment of interests (for example, common stock, a partnership interest or other means of exerting influence) in other entities, for example consolidation or use of the equity or cost methods of accounting. The accounting policy may also address the accounting treatment for intercompany accounts and transactions, noncontrolling interest, and the income statement treatment in consolidation for issuances of stock by a subsidiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

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+ Details

- Definition

Disclosure of accounting policy for determining an entity's fiscal year or other fiscal period. This disclosure may include identification of the fiscal period end-date, the length of the fiscal period, any reporting period lag between the entity and its subsidiaries, or equity investees. If a reporting lag exists, the closing date of the entity having a different period end is generally noted, along with an explanation of the necessity for using different closing dates. Any intervening events that materially affect the entity's financial position or results of operations are generally also disclosed.

+ References+ Details

- Definition

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

+ References+ Details