v3.19.2

Restructuring Charges and RIght of Use Asset Impairments - Narrative (Details) $ in Thousands	3 Months Ended						6 Months Ended
	Jun. 29, 2019 USD ($) ft²	Mar. 30, 2019 USD ($)	Sep. 29, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($) ft²	Jun. 29, 2019 USD ($) ft²	Jun. 30, 2018 USD ($)
Capital Leased Assets [Line Items]
Right of use asset impairment charge							$ 1,137
Lease obligation	$ 784						2,035
Restructuring charges	$ 2,758			$ 17			$ 2,989	$ 479
Headquarters Facility
Capital Leased Assets [Line Items]
Area of real estate property ceased (in sqft) | ft²	36,395					25,812	36,395
Area of real estate property (in sqft) | ft²	108,743					108,743	108,743
Right of use asset impairment charge	$ 1,100						$ 1,100
Lease obligation	700					$ 3,100	$ 700
Deferred rent liability						2,600
Impairment of leasehold	500					$ 500
Restructuring charges	$ 300	$ 200	$ 100	$ 500	$ 500

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