Revenues from Contracts - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Revenue from Contract with Customer [Abstract]
Change in net contract balance	$ 66.8
Revenue recognized related to contract liabilities	67.8
Large Power Projects \| South Africa
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Claims and unapproved change orders	$ 37.9
HVAC reportable segment \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	1 month
HVAC reportable segment \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	3 months
Detection and Measurement reportable segment \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	1 month
Detection and Measurement reportable segment \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	18 months
Power transformers \| Engineered Solutions reportable segment \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	6 months
Power transformers \| Engineered Solutions reportable segment \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	12 months
Process cooling equipment, services, and heat exchangers \| Engineered Solutions reportable segment \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	6 months
Process cooling equipment, services, and heat exchangers \| Engineered Solutions reportable segment \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	18 months
SPX Heat Transfer Business \| Engineered Solutions reportable segment \| Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	6 months
SPX Heat Transfer Business \| Engineered Solutions reportable segment \| Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	18 months
South African projects \| Engineered Solutions reportable segment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Customer Contract Terms	10 years

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- Definition

Increase (Decrease) in Contract with Customers, Net

+ References

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+ Details

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
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- 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

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- References

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- Definition

Amount of cost incurred on construction contract for unapproved change order, claim, or similar item subject to uncertainty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 910
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6471471&loc=d3e48698-109348

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