Liabilities for Dispositions and Discontinued Operations General Narrative (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Estimated 2014 Environmental Expenditures	$ 8
Estimated 2015 Environmental Expenditures	7
Environmental Expenditures, Balance Sheet Caption	liabilities for dispositions and discontinued operations
Environmental Loss Contingencies Term	20 years
Description of Remedial Actions	Remedial actions for these sites vary, but include on-site (and in certain cases off-site) removal or treatment of contaminated soils and sediments, recovery and treatment/remediation of groundwater, and source remediation and/or control.
Environmental Contingency, Loss Exposure in Excess of Accrual, High Estimate	$ 30
Environmental Applicability, Impact and Conclusion Disclosures	In addition, these prior dispositions and discontinued operations are exposed to the risk of reasonably possible additional losses in excess of the established liabilities. As of December 31, 2013, this amount could range up to $30 million, allocable over several of the applicable sites, and arises from uncertainty over the availability, feasibility or effectiveness of certain remediation technologies, additional or different contamination that may be discovered, development of new or more effective environmental remediation technologies and the exercise of discretion in interpretation of applicable law and regulations by governmental agencies.
Port Angeles, Washington [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Status of Dispositions and Discontinued Operations	closed in 1997
Total SWP sites [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Status of Dispositions and Discontinued Operations	ceased operations in 1989 except for investigation and remediation activities
Total SWP sites [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Applicability and Impact of Environmental Laws	SWP owns or has liability for nine inactive former wood treating sites that are subject to the Resource Conservation and Recovery Act (“RCRA”), the Comprehensive Environmental Response, Compensation and Liability Act of 1980 and/or other similar federal or state statutes relating to the investigation and remediation of environmentally-impacted sites.