Business Acquisitions - Summary of Pro Forma Information (Details) - Aclara - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Net sales	$ 1,180.4	$ 1,112.7	$ 3,385.8	$ 3,150.2
Net income attributable to Hubbell	$ 117.3	$ 77.4	$ 284.5	$ 193.7
Earnings Per Share:
Basic (USD per share)	$ 2.14	$ 1.41	$ 5.18	$ 3.52
Diluted (USD per share)	$ 2.13	$ 1.40	$ 5.16	$ 3.50