XML 309 R64.htm IDEA: XBRL DOCUMENT
v3.25.3

Composition Of Certain Financial Statement Captions (Schedule Of Other Non-Current Liabilities) (Details) - USD ($) $ in Thousands | Sep. 26, 2025 | Sep. 27, 2024 | Aug. 19, 2024
--- | --- | --- | ---
Composition Of Financial Statements [Line Items] |  |  |
Supplemental retirement plan obligations | $ 5,315 | $ 4,946 |
Non-current tax liabilities | 46,159 | 78,355 |
Other liabilities | 48,369 | 52,551 |
Other non-current liabilities | $ 99,843 | $ 135,852 |
GE Licensing |  |  |
Composition Of Financial Statements [Line Items] |  |  |
Contingent liabilities |  |  | $ 14,199

X
- Definition Composition Of Financial Statements [Line Items] + References No definition available. + Details
Name: | dlb_CompositionOfFinancialStatementsLineItems
Namespace Prefix: | dlb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Non-Current Tax Liabilities + References No definition available. + Details
Name: | dlb_NonCurrentTaxLiabilities
Namespace Prefix: | dlb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of preacquisition contingent liability assumed in business combination and recognized at acquisition date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479907/805-20-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 805 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479907/805-20-50-1 + Details
Name: | us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContingentLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_OtherLiabilitiesNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of liability, classified as noncurrent, for retirement benefits, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_OtherPostretirementBenefitsPayableNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 + Details
Name: | us-gaap_OtherSundryLiabilitiesNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=dlb_GELicensingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |