Convertible Notes, Other Debts And Capital Leases - 2020 Convertible Note Roll Forward (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 25, 2020	Dec. 31, 2019	Dec. 31, 2015
Debt Instrument [Line Items]
Convertible Debt, Current	$ 7,972	$ 43,375
Convertible Note due 2020
Debt Instrument [Line Items]
Principal amount	8,053	45,785	$ 128,250
Less: Debt discount, net of amortization	(72)	(2,151)
Less: Debt issuance costs, net of amortization	(9)	(259)
Convertible Debt, Current	$ 7,972	$ 43,375
Remaining amortization period (years)	2 months 12 days	10 months 24 days
Effective interest rate on liability component	9.94%	9.94%

The portion of the carrying value of long-term convertible debt as of the balance sheet date that is scheduled to be repaid within one year or in the normal operating cycle if longer. Convertible debt is a financial instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Amount, after accumulated amortization, of debt discount.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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