CONTINGENT LIABILITIES AND OTHER MATTERS (Details 3) - Site investigation and remediation - site	Apr. 02, 2016	Dec. 31, 2015
Environmental Matters
Number of sites	35	35
Number of third-party disposal sites for which entity is potentially responsible	24
Number of active sites	7

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:	spxc_SiteContingencyNumberOfSitesOnWhichEntityPotentiallyResponsible
Namespace Prefix:	spxc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant