Interim Condensed Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income/(Loss)	Total Dolby Laboratories, Inc.	Controlling Interest	Class A Common Stock [Member] Common Stock	Class A Common Stock [Member] Additional Paid-In Capital
Beginning balance at Sep. 29, 2017	$ 2,398,727		$ 61,331	$ 2,337,948	$ (7,753)	$ 2,391,627	$ 7,100
Beginning balance (in shares) at Sep. 29, 2017		101,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	15,451			15,030		15,030	421
Other comprehensive income, net of tax	(5,628)					(5,548)	(80)
Distributions to controlling interest	(1,022)						(1,022)
Stock-based compensation expense	53,476		53,476			53,476
Shares repurchased (in shares)								(1,000)
Repurchase of common stock	(90,480)		(90,479)			(90,480)
Cash dividends declared and paid on common stock	(49,596)			(49,596)		(49,596)
Common stock issued under employee stock plans	85,941		85,938			85,941
Common stock issued under employee stock plans (in shares)								3,000
Tax withholdings on vesting of restricted stock	(21,189)					(21,189)			$ (21,189)
Ending balance at Jun. 29, 2018	2,385,680		89,077	2,303,382	(13,301)	2,379,261	6,419
Ending balance (in shares) at Jun. 29, 2018		103,000
Beginning balance at Mar. 30, 2018	2,431,768		113,827	2,316,906	(5,616)	2,425,219	6,549
Beginning balance (in shares) at Mar. 30, 2018		102,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	3,259			3,116		3,116	143
Other comprehensive income, net of tax	(7,958)				(7,685)	(7,685)	(273)
Stock-based compensation expense	17,101		17,101			17,101
Repurchase of common stock	(55,487)		(55,487)			(55,487)
Cash dividends declared and paid on common stock	(16,640)			(16,640)		(16,640)
Common stock issued under employee stock plans	14,880		14,879			14,880
Common stock issued under employee stock plans (in shares)								1,000
Tax withholdings on vesting of restricted stock						(1,243)			(1,243)
Ending balance at Jun. 29, 2018	2,385,680		89,077	2,303,382	(13,301)	2,379,261	6,419
Ending balance (in shares) at Jun. 29, 2018		103,000
Beginning balance at Sep. 28, 2018	2,370,503		66,127	2,313,539	(15,832)	2,363,936	6,567
Beginning balance (in shares) at Sep. 28, 2018		102,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	211,570			211,233		211,233	337
Other comprehensive income, net of tax	1,202				1,336	1,336	(134)
Distributions to controlling interest	(1,015)						(1,015)
Stock-based compensation expense	$ 59,580		59,580			59,580
Shares repurchased (in shares)	(4,365,422)							(4,000)
Repurchase of common stock	$ (286,512)		(148,972)	(137,536)		(286,512)
Cash dividends declared and paid on common stock	(58,318)			(58,318)		(58,318)
Common stock issued under employee stock plans	45,027		45,026			45,027
Common stock issued under employee stock plans (in shares)								1,000
Tax withholdings on vesting of restricted stock						(21,761)			(21,761)
Ending balance at Jun. 28, 2019	2,320,276		0	2,328,918	(14,496)	2,314,521	5,755
Ending balance (in shares) at Jun. 28, 2019		99,000
Beginning balance at Mar. 29, 2019	2,352,857		0	2,361,607	(14,683)	2,347,024	5,833
Beginning balance (in shares) at Mar. 29, 2019		100,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	39,637			39,574		39,574	63
Other comprehensive income, net of tax	47				187	187	(140)
Distributions to controlling interest	(1)						(1)
Stock-based compensation expense	$ 18,863		18,863			18,863
Shares repurchased (in shares)	(1,000)
Repurchase of common stock	$ (88,632)		(35,651)	(52,980)		(88,632)
Cash dividends declared and paid on common stock	(19,283)			(19,283)		(19,283)
Common stock issued under employee stock plans	17,869		17,869			17,869
Tax withholdings on vesting of restricted stock						(1,081)			$ (1,081)
Ending balance at Jun. 28, 2019	$ 2,320,276		$ 0	$ 2,328,918	$ (14,496)	$ 2,314,521	$ 5,755
Ending balance (in shares) at Jun. 28, 2019		99,000