Debt (Interest Rate Swaps) (Details) - USD ($)	12 Months Ended
Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016
Derivative [Line Items]
Interest expense	$ 99,310,000	$ 63,972,000	$ 68,331,000
Interest Rate Swap 1 [Member]
Derivative [Line Items]
Interest Rate Swap Term	3 years
Notional Amount	$ 200,000,000
Pay Fixed Rate	1.1325%
Receive Current Floating Rate	2.5063%
Fair Value	$ 4,171,000
Interest Rate Swap [Member]
Derivative [Line Items]
Portion of the change in fair value considered ineffective	0	0	0
Interest expense	1,700,000	$ 500,000	$ 100,000
Gain expected to be reclassified into earnings within the next twelve months	$ 2,800,000

Nominal or face amount used to calculate payments on the derivative asset.

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Fixed interest rate related to the interest rate derivative.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount of the cost of borrowed funds accounted for as interest expense.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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