Basis of Presentation and Responsibility for Interim Financial Statements - Adoption of New Accounting Standards (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net periodic benefit cost		$ 4.0	$ 4.1	$ 7.6	$ 12.4
Reclassification from AOCI to retained earnings	$ 215.8
Reduction in prepaid long-term asset	254.3
Deferred tax asset, income tax expense	38.5
nVent
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI to retained earnings	$ 174.6
Effect of Change | Accounting Standards Update 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net periodic benefit cost			$ 1.4		$ 4.1