Interim Condensed Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]	Total Dolby Laboratories,Inc.[Member]	Controlling Interest [Member]
Beginning balance at Sep. 27, 2013	$ 1,500,026	$ 102	$ 18,812	$ 1,454,382	$ 7,814	$ 1,481,110	$ 18,916
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	162,358			160,162		160,162	2,196
Translation adjustments, net of tax of $829 and $(64), respectively	846				408	408	438
Unrealized gains (losses) on available-for-sale securities, net of tax of $(327) and $(98), respectively	(456)				(456)	(456)
Stock-based compensation expense	48,773		48,773			48,773
Repurchase of common stock	(40,958)		(40,957)			(40,958)
Tax benefit/(deficiency) from the stock incentive plans	(263)		(263)			(263)
Common stock issued under employee stock plans	23,858	2	23,856			23,858
Tax withholdings on vesting of restricted stock	(9,221)		(9,221)			(9,221)
Exercise of class B stock options	289		289			289
Ending balance at Jun. 27, 2014	1,686,164	103	41,289	1,614,544	8,678	1,664,614	21,550
Beginning balance at Sep. 26, 2014	1,731,648	103	46,415	1,660,485	3,014	1,710,017	21,631
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	136,325			134,837		134,837	1,488
Translation adjustments, net of tax of $829 and $(64), respectively	(10,726)				(10,341)	(10,341)	(385)
Unrealized gains (losses) on available-for-sale securities, net of tax of $(327) and $(98), respectively	64				64	64
Distributions to controlling interest	(5,628)			0		0	(5,628)
Stock-based compensation expense	50,822		50,822			50,822
Repurchase of common stock	(47,956)	(1)	(47,955)			(47,956)
Cash dividends declared and paid on common stock	(30,744)			(30,744)		(30,744)
Tax benefit/(deficiency) from the stock incentive plans	(1,167)		(1,167)			(1,167)
Common stock issued under employee stock plans	28,050	2	28,048			28,050
Tax withholdings on vesting of restricted stock	(12,918)		(12,918)			(12,918)
Exercise of class B stock options	7		7			7
Ending balance at Jun. 26, 2015	$ 1,839,983	$ 104	$ 65,586	$ 1,764,578	$ (7,391)	$ 1,822,877	$ 17,106