Commitments and Contingencies - Facility and Equipment Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 04, 2021	Jun. 28, 2020	Jul. 04, 2021	Jun. 28, 2020
Loss Contingencies [Line Items]
Operating lease expense	$ 3,701	$ 3,516	$ 7,415	$ 6,934
Sublease income	(105)	(20)	(211)	(55)
Rent expense	3,596	3,496	7,204	6,879
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows for operating leases	4,437	3,888	8,600	7,197
Right-of-use assets obtained in exchange for lease obligations	$ 0	$ 963	$ 11,528	$ 13,424
Weighted-average remaining lease term (in years) - operating leases	6 years 3 months 18 days	6 years 8 months 12 days	6 years 3 months 18 days	6 years 8 months 12 days
Weighted-average discount rate - operating leases	8.80%	9.00%	8.80%	9.00%
Minimum
Loss Contingencies [Line Items]
Lessee, operating lease, renewal term	1 year		1 year
Maximum
Loss Contingencies [Line Items]
Lessee, operating lease, renewal term	10 years		10 years

Cash Flow, Lessee [Abstract]

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- Definition

Sublease Loss (Income)

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-SubTopic 20
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

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- Definition

Amount of operating lease expense. Excludes sublease income.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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