Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 26, 2015
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Assets fair value	[1]	$ 865	$ 60
Liabilities fair value	[1]	(1,143)	(3,318)
Commodity Contracts [Member] | Cash Flow Hedging [Member] | Long [Member]
Derivatives, Fair Value [Line Items]
Open future contracts to purchase copper		$ 10,200
Time period for open copper future contract purchases		12 months
Fair value of future contracts with gain (loss) position		$ 800
Commodity Contracts [Member] | Fair Value Hedging [Member] | Short [Member]
Derivatives, Fair Value [Line Items]
Open future contracts to sell copper		$ 28,700
Time period for open copper future contract sales		3 months
Fair value of future contracts with gain (loss) position		$ (300)
Other Current Asset [Member] | Commodity Contracts [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other current assets: Gain positions		1,013	60
Other current assets: Loss positions		(148)	0
Other Current Asset [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other assets: Gain positions		0	0
Other Assets [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other assets: Gain positions		0	0
Other Current Liabilities [Member] | Commodity Contracts [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Gain positions		564	238
Other current liability: Loss positions		(920)	(1,864)
Other Current Liabilities [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other current liability: Loss positions		(787)	0
Other Liabilities [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Other liabilities: Loss positions		$ 0	$ (1,692)

[1] Does not include the impact of cash collateral provided to counterparties.