Summary Of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 01, 2022	Mar. 26, 2021	Apr. 01, 2022	Mar. 26, 2021	Sep. 24, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 58,934		$ 58,934		$ 67,128
Total lease liabilities	63,604		63,604
Revenues	334,371	$ 319,558	686,004	$ 709,432
Gross margin	298,856	287,180	617,780	641,750
Provision for income taxes	(6,932)	(9,022)	(18,364)	(33,294)
Net income (loss) attributable to Dolby Laboratories, Inc.	$ 36,720	$ 76,217	$ 116,734	$ 211,415
Diluted (in usd per share)	$ 0.36	$ 0.73	$ 1.13	$ 2.02
Accounts receivable, net	$ 227,263		$ 227,263		232,609
Contract assets, net of allowance for credit losses of $125 and $208	258,846		258,846		182,316
Prepaid expenses and other current assets	68,312		68,312		62,737
Other non-current assets	57,464		57,464		61,257
Accrued liabilities	228,545		228,545		262,728
Contract liabilities	22,109		22,109		18,473
Non-current contract liabilities	24,569		24,569		23,713
Other non-current liabilities	104,083		104,083		105,310
Retained earnings	2,615,354		2,615,354		$ 2,607,909
Net income	$ 36,519	$ 76,345	116,529	$ 219,035
Deferred income taxes			(19,363)	(16,992)
Accounts receivable, net			3,498	(102,791)
Contract assets, net			(76,447)	(72,197)
Prepaid expenses and other assets			(1,683)	10,552
Accounts payable and other liabilities			(37,472)	26,926
Contract liabilities			4,364	3,589
Net cash provided by operating activities			$ 94,659	$ 165,628