Commitments, Contingent Liabilities and Other Matters (Details 3) (Site investigation and remediation)	Dec. 31, 2011 site
Site investigation and remediation
Environmental Matters
Number of sites	92
Number of third-party disposal sites for which entity is potentially responsible	28
Number of active sites	12

Represents the number of offsite, third-party disposal sites for which the entity is potentially responsible and have received notices of potential liability pursuant to various environmental laws.

No definition available.

Name:	spw_SiteContingencyNumberOfSitesOnWhichEntityPotentiallyResponsible
Namespace Prefix:	spw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant