Income Taxes (Details) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Mar. 31, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Income tax (provisions) expense	$ 2,699,000	$ 3,365,000		$ 4,282,000	$ 6,372,000
Deferred taxes, charge to earnings			3,000,000	4,283,000	7,268,000
Interest and penalties in tax provision, net benefit	(100,000)	(100,000)		(100,000)	(100,000)
Accrued for the payment of interest	100,000			100,000		100,000
Accrued as a receivable for interest, open tax refund	0			0		800,000
REIT [Member]
Income tax (provisions) expense				0	300,000
Potlatch TRS [Member]
Income tax (provisions) expense	(2,700,000)	(3,700,000)		(4,300,000)	(3,500,000)
Income tax benefit related to continuing operations		$ 300,000