Income Taxes	9 Months Ended
Sep. 30, 2011
Income Taxes Note Disclosure [Abstract]
Income Taxes	Income Taxes As a real estate investment trust, or REIT, if we meet certain requirements, we generally are not subject to federal and state corporate income taxes on our income from investments in real estate that we distribute to our shareholders. We are, however, subject to corporate taxes on built-in gains (the excess of fair market value at January 1, 2006 over tax basis on that date) with respect to the REIT's sale of any real property owned at such date within the first ten years following our conversion to a REIT, except for sales occurring in 2011. The Small Business Jobs Act of 2010 modifies the built-in gains provisions to exempt sales of real properties by a REIT in 2011, if five years of the recognition period has elapsed before January 1, 2011. If applicable, the built-in gains tax is eliminated or deferred if sale proceeds are reinvested in like-kind property in accordance with the like-kind exchange provisions of the Internal Revenue Code. The built-in gains tax is not applicable to the sale of timber pursuant to a stumpage sale agreement or timber deed. For the quarters ended September 30, 2011 and 2010, we recorded income tax provisions related to our taxable REIT subsidiary, or Potlatch TRS, of $3.2 million and $1.6 million, respectively, due to pre-tax income. For the nine months ended September 30, 2011 and 2010, we recorded income tax provisions related to Potlatch TRS of $7.5 million and $5.1 million, respectively, due to pre-tax income. For the nine months ended September 30, 2011 and 2010, we recorded income tax expense of $0 and $0.4 million, respectively, related to the sale of REIT properties that were not deferred in accordance with the like-kind exchange provisions of the Internal Revenue Code. The Patient Protection and Affordable Care Act, as amended by the Health Care and Reconciliation Act of 2010 included a change in the deductibility of drug expenses reimbursed under the Medicare Part D retiree drug subsidy program beginning after 2012. As a result of this legislation, deferred taxes associated with our retiree health care liabilities based on prior law were required to be adjusted, resulting in a $3.0 million net charge to earnings in the first three months of 2010. During the nine months ended September 30, 2010, we recorded an income tax benefit related to continuing operations of Potlatch TRS of $0.3 million attributable to the Part D reimbursements received during the period that were non-taxable. We reviewed our tax positions at September 30, 2011 and determined that no uncertain tax positions were taken during the first nine months of 2011, and that no new information was available that would require derecognition of previously taken positions. We reflect accrued interest related to tax obligations, as well as penalties, in our provision for income taxes. During the quarters and nine months ended September 30, 2011 and 2010, we recognized a net benefit of less than $0.1 million related to interest and penalties in our tax provision. At September 30, 2011 and December 31, 2010, we had less than $0.1 million accrued for the payment of interest. At September 30, 2011 and December 31, 2010, we had $0 and $0.8 million, respectively, accrued as a receivable for interest with respect to open tax refunds.

Income Taxes

9 Months Ended

Sep. 30, 2011

Income Taxes Note Disclosure [Abstract]

As a real estate investment trust, or REIT, if we meet certain requirements, we generally are not subject to federal and state corporate income taxes on our income from investments in real estate that we distribute to our shareholders. We are, however, subject to corporate taxes on built-in gains (the excess of fair market value at January 1, 2006 over tax basis on that date) with respect to the REIT's sale of any real property owned at such date within the first ten years following our conversion to a REIT, except for sales occurring in 2011. The Small Business Jobs Act of 2010 modifies the built-in gains provisions to exempt sales of real properties by a REIT in 2011, if five years of the recognition period has elapsed before January 1, 2011. If applicable, the built-in gains tax is eliminated or deferred if sale proceeds are reinvested in like-kind property in accordance with the like-kind exchange provisions of the Internal Revenue Code. The built-in gains tax is not applicable to the sale of timber pursuant to a stumpage sale agreement or timber deed.

For the quarters ended September 30, 2011 and 2010, we recorded income tax provisions related to our taxable REIT subsidiary, or Potlatch TRS, of $3.2 million and $1.6 million, respectively, due to pre-tax income. For the nine months ended September 30, 2011 and 2010, we recorded income tax provisions related to Potlatch TRS of $7.5 million and $5.1 million, respectively, due to pre-tax income.

For the nine months ended September 30, 2011 and 2010, we recorded income tax expense of $0 and $0.4 million, respectively, related to the sale of REIT properties that were not deferred in accordance with the like-kind exchange provisions of the Internal Revenue Code.

The Patient Protection and Affordable Care Act, as amended by the Health Care and Reconciliation Act of 2010 included a change in the deductibility of drug expenses reimbursed under the Medicare Part D retiree drug subsidy program beginning after 2012. As a result of this legislation, deferred taxes associated with our retiree health care liabilities based on prior law were required to be adjusted, resulting in a $3.0 million net charge to earnings in the first three months of 2010. During the nine months ended September 30, 2010, we recorded an income tax benefit related to continuing operations of Potlatch TRS of $0.3 million attributable to the Part D reimbursements received during the period that were non-taxable.

We reviewed our tax positions at September 30, 2011 and determined that no uncertain tax positions were taken during the first nine months of 2011, and that no new information was available that would require derecognition of previously taken positions.

We reflect accrued interest related to tax obligations, as well as penalties, in our provision for income taxes. During the quarters and nine months ended September 30, 2011 and 2010, we recognized a net benefit of less than $0.1 million related to interest and penalties in our tax provision. At September 30, 2011 and December 31, 2010, we had less than $0.1 million accrued for the payment of interest. At September 30, 2011 and December 31, 2010, we had $0 and $0.8 million, respectively, accrued as a receivable for interest with respect to open tax refunds.