v3.10.0.1
Document And Entity Information - USD ($)
12 Months Ended
Sep. 28, 2018
Oct. 26, 2018
Mar. 31, 2017
Entity Registrant Name Dolby Laboratories, Inc.    
Entity Central Index Key 0001308547    
Current Fiscal Year End Date --09-28    
Entity Filer Category Large Accelerated Filer    
Document Type 10-K    
Document Period End Date Sep. 28, 2018    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 1,684,632,316
Class A Common Stock [Member]      
Entity Common Stock, Shares Outstanding   64,002,056  
Class B Common Stock [Member]      
Entity Common Stock, Shares Outstanding   39,261,035