Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payment on derivative.

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Fair value as of the balance sheet date of all price risk derivative assets designated as cash flow hedging instruments.

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DERIVATIVE FINANCIAL INSTRUMENTS (Details) lb in Millions	9 Months Ended	12 Months Ended
DERIVATIVE FINANCIAL INSTRUMENTS (Details) lb in Millions	Sep. 26, 2020 USD ($) lb	Dec. 31, 2019 USD ($) lb	Mar. 31, 2018 USD ($)
Initial Swaps \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Aggregate notional amount	$ 240,500,000		$ 260,000,000.0
Fixed rate (percentage)	2.535%
Additional Swaps \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Aggregate notional amount	$ 248,400,000
Fixed rate (percentage)	1.061%
Swaps
Derivative Financial Instruments
Unrealized gain (loss) recorded in AOCI	$ (7,600,000)	$ (1,900,000)
Swaps \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Derivative liability	10,000,000.0
Swaps \| Derivative contracts designated as hedging instruments \| Short-term Liability
Derivative Financial Instruments
Derivative liability	3,500,000
Swaps \| Derivative contracts designated as hedging instruments \| Long-term Liability
Derivative Financial Instruments
Derivative liability		2,500,000
FX Forward Contracts
Derivative Financial Instruments
Aggregate notional amount	7,200,000	26,000,000.0
Commodity contracts
Derivative Financial Instruments
Unrealized gain (loss) recorded in AOCI	700,000	300,000
Fair value of derivative contract - asset	1,100,000	$ 400,000
Gain (loss) to be reclassified over the next 12 months	$ 700,000
Commodity contracts \| Derivative contracts designated as hedging instruments
Derivative Financial Instruments
Notional amount of commodity contracts (in pounds of copper) \| lb	3.9	3.4