Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 1,144.1	$ 1,179.7	$ 1,166.7	$ 991.2	$ 917.7	$ 950.5	$ 948.3	$ 852.3	$ 4,481.7	$ 3,668.8	$ 3,505.2
Cost of goods sold	823.5	830.7	818.8	708.3	628.3	642.9	652.8	589.7	3,181.3	2,513.7	2,400.1
Gross profit	320.6	349.0	347.9	282.9	289.4	307.6	295.5	262.6	1,300.4	1,155.1	1,105.1
Selling & administrative expenses	184.0	185.2	191.0	183.3	162.9	157.5	161.1	154.8	743.5	636.3	615.3
Net income	89.2	114.7	102.4	59.8	22.4	82.8	80.8	63.9	366.1	249.9	297.8
Net income attributable to Hubbell	$ 88.0	$ 113.6	$ 100.3	$ 58.3	$ 20.4	$ 80.8	$ 79.1	$ 62.8	$ 360.2	$ 243.1	$ 293.0
Earning Per Share - Basic (USD per share)	$ 1.61	$ 2.07	$ 1.83	$ 1.06	$ 0.37	$ 1.47	$ 1.44	$ 1.13	$ 6.57	$ 4.42	$ 5.26
Earning Per Share - Diluted (USD per share)	$ 1.60	$ 2.06	$ 1.82	$ 1.05	$ 0.37	$ 1.47	$ 1.43	$ 1.13	$ 6.54	$ 4.39	$ 5.24
Tax Cuts and Jobs Act, provisional income tax expense (benefit)					$ 56.5					$ 6.0
Tax act impact on EPS (USD per share)					$ 1.02