Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Gross amount of debt extinguished.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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DEBT - New and Old Term Loan Credit Agreements (Details) - USD ($)		3 Months Ended		9 Months Ended
	Sep. 28, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Loss on debt extinguishment				$ 219,000	$ 104,000
Current portion of long-term debt		$ 1,500,000		1,500,000		$ 0
Term loan credit agreement due 2027
Debt Instrument [Line Items]
Amortization of debt issuance costs and discounts		100,000	$ 100,000	100,000	200,000
New Term Loan Credit Agreement \| Term loan credit agreement due 2027
Debt Instrument [Line Items]
Notes issued, aggregate principal amount	$ 150,000,000
Percentage of tranche loan amount on Equal quarterly installments	0.25%
Debt Instrument, LIBOR Floor Rate	0.75%
Proceeds from issuance of long-term debt	$ 148,500,000
Long-term line of credit	$ 150,000,000.0
Current portion of long-term debt		1,500,000		1,500,000
Interest paid		0
New Term Loan Credit Agreement \| London Interbank Offered Rate (LIBOR) \| Term loan credit agreement due 2027
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.25%
New Term Loan Credit Agreement \| Base Rate \| Term loan credit agreement due 2027
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.25%
Old Term Loan Credit Agreement \| Term loan credit agreement due 2027
Debt Instrument [Line Items]
Extinguishment of debt, amount		135,200,000
Loss on debt extinguishment		200,000
Interest paid		$ 900,000	1,900,000	$ 3,300,000	6,300,000
Repayments of long-term debt			$ 15,000,000.0		$ 30,500,000