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 Stockholders' Equity - Dolby Laboratories, Inc.	Controlling Interest	Class A Common Stock [Member] Common Stock	Class A Common Stock [Member] Additional Paid-In Capital
Beginning balance (in shares) at Sep. 27, 2019		99,000
Beginning balance at Sep. 27, 2019	$ 2,313,030		$ 0	$ 2,327,877	$ (20,625)	$ 2,307,351	$ 5,679
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	48,591			48,753		48,753	(162)
Other comprehensive income, net of tax	2,742				2,565	2,565	177
Distributions to controlling interest	(283)						283
Stock-based compensation expense	22,614		22,614			22,614
Shares repurchased (in shares)		0
Repurchase of common stock	(30,003)		(26,705)	(3,298)		(30,003)
Cash dividends declared and paid on common stock	(22,081)			(22,081)		(22,081)
Common stock issued under employee stock plans (in shares)								0
Common stock issued under employee stock plans	24,373		24,373			24,373
Tax withholdings on vesting of restricted stock (in shares)								0
Tax withholdings on vesting of restricted stock	(20,282)					(20,282)	0		$ (20,282)
Ending balance (in shares) at Dec. 27, 2019		99,000
Ending balance at Dec. 27, 2019	2,338,701		0	2,351,251	(18,060)	2,333,290	5,411
Beginning balance (in shares) at Sep. 25, 2020		99,000
Beginning balance at Sep. 25, 2020	2,438,405		0	2,443,138	(10,594)	2,432,643	5,762
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	142,690			135,198		135,198	7,492
Other comprehensive income, net of tax	10,149				9,986	9,986	163
Distributions to controlling interest	(7,362)						(7,362)
Stock-based compensation expense	$ 26,313		26,313			26,313
Shares repurchased (in shares)	(450,399)	0
Repurchase of common stock	$ (39,985)		(49,550)	9,565		(39,985)
Cash dividends declared and paid on common stock	(22,231)			(22,231)		(22,231)
Common stock issued under employee stock plans	51,323	$ 2	51,321			51,323
Tax withholdings on vesting of restricted stock (in shares)								(1,000)
Tax withholdings on vesting of restricted stock	(28,085)				0	(28,085)	0		$ (28,084)
Ending balance (in shares) at Dec. 25, 2020		100,000
Ending balance at Dec. 25, 2020	$ 2,571,217		$ 0	$ 2,565,670	$ (608)	$ 2,565,162	$ 6,055