v3.8.0.1

Restructuring Charges - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) ft²	Sep. 24, 2016 USD ($)	Sep. 30, 2017 USD ($) ft²	Apr. 14, 2016 ft²
Capital Leased Assets [Line Items]
Lease obligation	$ 3,000		$ 3,000
Restructuring charges	3,600		$ 3,620
Impairment of leasehold	500
Write-off of deferred rent and tenant improvement allowances	$ 1,100
Massachusetts
Capital Leased Assets [Line Items]
Area of real estate property | ft²				108,743
Massachusetts | Property Subject to Operating Lease
Capital Leased Assets [Line Items]
Area of real estate property | ft²	25,812		25,812	10,362
Sublease loss liability		$ 500
Related lease expense		$ 200

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Write-off of Deferred Rent and Tenant Improvement Allowances

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Area of a real estate property.

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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The adjustment to reduce the value of existing agreements that specify the lessee's rights to use the leased property. This expense is charged when the estimates of future profits generated by the leased property are reduced.

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