Long-Term Debt Long-Term Debt (Schedule of Interest Rate Swaps) (Details) $ in Thousands	Dec. 27, 2017 USD ($)
Derivative [Line Items]
Interest rate swaps, net	$ 2,200
Interest rate swaps, assets	100
Interest rate swaps, liability	2,300
Interest Rate Swaps 2015-2018 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 120,000
Average fixed interest rate on interest rate swap	3.13%
Interest Rate Swaps 2018-2025 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 170,000
Average fixed interest rate on interest rate swap	4.44%
Interest Rate Swaps 2018-2026 [Member]
Derivative [Line Items]
Derivative, notional amount	$ 50,000
Average fixed interest rate on interest rate swap	4.46%

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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