Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Designated as Hedging Instrument | Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 99	$ 247
Liability Derivatives, Fair Value	115	91
Designated as Hedging Instrument | Fair Value Hedging [Member] | Interest rate contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	99	32
Designated as Hedging Instrument | Fair Value Hedging [Member] | Interest rate contracts [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value		215
Designated as Hedging Instrument | Fair Value Hedging [Member] | Interest rate contracts [Member] | Other Long-term Obligations [Member]
Derivatives, Fair Value [Line Items]
Liability Derivatives, Fair Value	115	91
Designated as Hedging Instrument | Cash Flow Hedging [Member] | Interest rate contracts [Member] | Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	924	$ 1,148
Derivatives not designated as Hedging Instrument [Member] | Lumber Price Contracts [Member] | Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 3,265