Balance sheet components - Expected revenue recognition (Details) $ in Thousands	Dec. 29, 2018 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred revenue expected to be recognized, remainder of fiscal 2019	$ 9,451
Deferred revenue expected to be recognized, fiscal 2020	12,051
Deferred revenue expected to be recognized, fiscal 2021	10,638
Deferred revenue expected to be recognized, fiscal 2022	8,792
Deferred revenue expected to be recognized, thereafter	14,521
Total deferred revenue expected to be recognized	$ 55,453

Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, After Year Five

No definition available.

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Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, Remainder of Fiscal Year

No definition available.

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Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, Total

No definition available.

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Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, Year Four

No definition available.

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Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, Year Three

No definition available.

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Contract with Customer, Liability, Deferred Revenue Expected to be Recognized, Year Two

No definition available.

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Namespace Prefix:	sono_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

No definition available.

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