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Description of Business and Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($) segment $ / shares	Dec. 31, 2020	Jan. 01, 2021 USD ($)	Sep. 29, 2020 $ / shares
Significant Accounting Policies [Line Items]
Number of operating segments \| segment	1
Common stock, par value (in USD per share) \| $ / shares	$ 0.0001			$ 0.0001
Cash and cash equivalents	$ 324,500
Lease assets	17,654
Lease liabilities	$ 18,597
Impact of Adoption
Significant Accounting Policies [Line Items]
Lease assets			$ 19,400
Lease liabilities			$ 20,400
Accounts Payable \| Supplier Concentration Risk \| One Vendor
Significant Accounting Policies [Line Items]
Concentration percentage	33.00%	34.00%
Two Customers \| Accounts Receivable \| Customer Concentration Risk
Significant Accounting Policies [Line Items]
Concentration percentage	44.00%	47.00%
Revolving Credit Facility \| 2020 Revolving Line \| Line of Credit
Significant Accounting Policies [Line Items]
Available borrowing capacity	$ 25,000