v2.3.0.15
Document And Entity Information (USD $)
12 Months Ended
Sep. 30, 2011
Apr. 01, 2011
Nov. 09, 2011
Class A Common Stock [Member]
Nov. 09, 2011
Class B Common Stock [Member]
Document Type10-K   
Amendment Flagfalse   
Document Period End DateSep. 30, 2011
Document Fiscal Year Focus2011   
Document Fiscal Period FocusFY   
Entity Registrant NameDolby Laboratories, Inc.   
Entity Central Index Key0001308547   
Current Fiscal Year End Date--09-30   
Entity Filer CategoryLarge Accelerated Filer   
Entity Common Stock, Shares Outstanding  51,438,77357,297,554
Entity Voluntary FilersNo   
Entity Current Reporting StatusYes   
Entity Well-known Seasoned IssuerYes   
Entity Public Float $ 2,100,000,000