Financial Instruments and Concentration of Risk (Effect Of Derivatives on the Consolidated Statement of Operations) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Derivatives designated as hedging instruments [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	$ 868		$ 1,027		$ 481
Derivatives designated as hedging instruments [Member] | Interest expense [Member] | Interest rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss) on hedging instrument\derivative	868	[1]	1,027	[1]	481	[1]
Derivatives not designated as hedging instruments [Member] | Lumber contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Income, Net	(876)		4,520		(2,876)
Derivatives not designated as hedging instruments [Member] | Cost of goods sold [Member] | Lumber contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Realized gain (loss) on hedging instrument\derivative	(396)		1,164		0
Unrealized gain (loss) on derivative	$ (480)		$ 3,356		$ (2,876)

[1] 1 Realized gain on hedging instrument consists of net cash settlements and interest accruals on the interest rate swaps during the period.