v3.19.2

Fair Value Measurements - 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 ($) ft²	Jun. 30, 2018 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Restructuring charges	$ 2,758			$ 17			$ 2,989	$ 479
Right of use asset impairment charge							1,137
Lease obligation	784						2,035
Loss on impairment of goodwill and intangible assets	8,183			0			8,183	$ 0
Goodwill impairment	$ 5,300						$ 5,325
Headquarters Facility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Area of real estate property ceased (in sqft) | ft²	36,395					25,812	36,395
Restructuring accrual	$ 600						$ 600
Restructuring charges	300	$ 200	$ 100	$ 500	$ 500
Right of use asset impairment charge	1,100						1,100
Lease obligation	700					$ 3,100	700
Impairment of leasehold	500					$ 500
Proprietary software
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss on impairment of intangible assets	$ 2,900						$ 2,900

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