Restructuring plan - Summary of Restructuring and Related Costs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 27, 2020	Jun. 27, 2020
Restructuring Cost and Reserve [Line Items]
Employee related costs	$ 8,985
ROU asset impairment and abandonment charges	8,139
Property and equipment abandonment charges	5,699
Other restructuring costs	3,337
Total	26,160	$ 12,162
Restructuring charges	26,160	$ 12,162
Research and development
Restructuring Cost and Reserve [Line Items]
Total	4,949
Restructuring charges	4,949
Sales and marketing
Restructuring Cost and Reserve [Line Items]
Total	19,788
Restructuring charges	19,788
General and administrative
Restructuring Cost and Reserve [Line Items]
Total	1,423
Restructuring charges	$ 1,423

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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