XML 87 R67.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Employee Benefit Plans - Defined Contribution Retirement Plans (Details) - USD ($) shares in Thousands, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
The DC Plan |  |  |
Defined Contribution Retirement Plans |  |  |
Maximum voluntary contribution by eligible U.S. employees as a percentage of their compensation | 50.00% |  |
Number of shares contributed | 334 | 605 | 434
Compensation expense | $ 8.7 | $ 8.8 | $ 10.2
Supplemental Retirement Savings Plan (SRSP) |  |  |
Defined Contribution Retirement Plans |  |  |
Compensation expense | 0.2 | 0.7 | $ 0.7
Supplemental Retirement Savings Plan (SRSP) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Defined Contribution Retirement Plans |  |  |
Fair value of assets | $ 21.2 | $ 19.1 |

X
- Definition Defined Contribution Plan, Fair Value of Plan Assets + References No definition available. + Details
Name: | spxc_DefinedContributionPlanFairValueofPlanAssets
Namespace Prefix: | spxc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Represents the number of shares contributed by the entity under the defined contribution plan. + References No definition available. + Details
Name: | spxc_DefinedContributionPlanNumberOfSharesContributed
Namespace Prefix: | spxc_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
Name: | us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanDisclosureLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
Name: | us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_SupplementalEmployeeRetirementPlanDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |