Interim Condensed Consolidated Statements Of Operations (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2021	Dec. 25, 2020
Related party rent expense:
Included in operating expenses	$ 0	$ 16
Included in net income attributable to controlling interest	$ 71	$ 119

Costs and Expenses, Related Party Attributable to Controlling Interest

No definition available.

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Namespace Prefix:	dlb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration