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Fixed interest rate related to the interest rate derivative.

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Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

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Derivatives and Hedging - Narrative (Details) $ in Thousands, $ in Thousands			9 Months Ended
	Nov. 08, 2018 USD ($)	Jan. 08, 2018 USD ($)	Sep. 28, 2019 USD ($)	Sep. 28, 2019 CAD ($)	Dec. 29, 2018 USD ($)	Dec. 29, 2018 CAD ($)
Interest Rate Swap Agreement - 2018 Swap 1
Derivative [Line Items]
Term of derivative instrument		3 years
Interest Rate Swap Agreement - 2018 Swap 2
Derivative [Line Items]
Term of derivative instrument	3 years
Not Designated as Hedging Instrument \| Interest rate swaps
Derivative [Line Items]
Gain (loss) on change in fair value			$ 3,217
Not Designated as Hedging Instrument \| Interest Rate Swap Agreement - 2018 Swap 1
Derivative [Line Items]
Derivative, Notional Amount		$ 90,000
Fixed interest rate			2.30%	2.30%
Basis spread on variable rate		4.00%
Variable interest rate			6.30%	6.30%
Not Designated as Hedging Instrument \| Interest Rate Swap Agreement - 2018 Swap 2
Derivative [Line Items]
Derivative, Notional Amount	$ 60,000
Fixed interest rate			2.10%	2.10%
Basis spread on variable rate	4.00%
Variable interest rate			6.10%	6.10%
Not Designated as Hedging Instrument \| Foreign exchange forward contracts
Derivative [Line Items]
Derivative, Notional Amount				$ 5,999		$ 5,790
Derivative liability					$ 152
Gain (loss) on change in fair value			$ 13
Derivative asset			5
Other Current Liabilities [Member]
Derivative [Line Items]
Business Combination, Contingent Consideration, Liability, Current			(2,275)
Other noncurrent liabilities
Derivative [Line Items]
Business Combination, Contingent Consideration, Liability, Noncurrent			(15,825)
Other noncurrent liabilities \| Not Designated as Hedging Instrument \| Interest rate swaps
Derivative [Line Items]
Derivative liability			$ (4,201)
Other noncurrent liabilities \| Not Designated as Hedging Instrument \| Interest Rate Swap Agreement - 2018 Swap 2
Derivative [Line Items]
Derivative liability					(1,378)
Other noncurrent assets \| Not Designated as Hedging Instrument \| Interest Rate Swap Agreement - 2018 Swap 1
Derivative [Line Items]
Derivative asset					$ 394