v3.10.0.1

Fair Value Measurements - Narrative (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 29, 2018 USD ($) ft² | Mar. 31, 2018 USD ($) | Sep. 29, 2018 USD ($) ft² | Sep. 30, 2017 USD ($) | Dec. 30, 2017 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Change in fair value of contingent consideration |  |  | $ 257 | $ 0 |
Restructuring accrual | $ 2,751 |  | 2,751 |  | $ 3,494
Restructuring charges | $ 100 | $ 500 | $ 187 |  |
Massachusetts |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Area of real estate property | ft² | 108,743 |  | 108,743 |  |
Massachusetts | Property Subject to Operating Lease |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Area of real estate property | ft² | 25,812 |  | 25,812 |  |
Restructuring accrual | $ 600 |  | $ 600 |  |
Restructuring charges | $ 100 | $ 500 |  |  |
Fair Value, Measurements, Recurring | Level 3 |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Change in fair value of contingent consideration |  |  | $ 257 |  |

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