Leases - Components of operating lease costs (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 27, 2020 |
Sep. 29, 2019 |
Sep. 27, 2020 |
Sep. 29, 2019 |
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| Leases [Abstract] | ||||
| Operating lease cost | $ 6,500 | $ 6,496 | $ 19,523 | $ 19,082 |
| Variable lease cost | 143 | 315 | 360 | 865 |
| Lease cost | $ 6,643 | $ 6,811 | $ 19,883 | $ 19,947 |
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- Definition Amount of lease cost recognized by lessee for lease contract. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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