Contingent Liabilities and Other Matters - General (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Carrying values of accruals	$ 575.7	$ 592.4
Proceeds from insurance recoveries	35.4	47.1	$ 45.3
Payments for asbestos-related matters, net of insurance recoveries	19.3	13.1	9.7
Recorded charges related to asbestos product liability matters	21.3	10.1	4.8
Gain (Loss) on Disposition of Discontinued Operations, Net of Tax
Loss Contingencies [Line Items]
Recorded charges related to asbestos product liability matters	2.1	3.8	0.4
Income From Continuing Operations Before Income Taxes
Loss Contingencies [Line Items]
Recorded charges related to asbestos product liability matters	19.2	6.3	$ 4.4
Other Long Term Liabilities
Loss Contingencies [Line Items]
Accruals included in other long-term liabilities	499.8	517.6
Other Long Term Liabilities \| Asbestos Related Claims
Loss Contingencies [Line Items]
Accruals included in other long-term liabilities	$ 479.9	$ 498.1
Buildings \| SPX Flow, Inc \| Discontinued Operations, Disposed of by Means Other than Sale, Spinoff
Loss Contingencies [Line Items]
Duration of office lease agreement	5 years
Annual lease costs	$ 2.1

Liability For Asbestos And Environmental Claims, Proceeds From Insurance Recoveries

No definition available.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount, before effects of reinsurance, of expense for claims incurred and costs incurred in the claim settlement process attributable to asbestos and environmental claims.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
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- Definition

Amount, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process attributable to asbestos and environmental claims.

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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.

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Amount of loss contingency liability.

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Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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