Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator:
Net income attributable to Hubbell	$ 80.8	$ 86.7	$ 222.7	$ 228.6
Less: Earnings allocated to participating securities	(0.3)	(0.3)	(0.7)	(0.7)
Net income available to common shareholders	$ 80.5	$ 86.4	$ 222.0	$ 227.9
Denominator [Abstract]
Average number of common shares outstanding (in shares)	54.6	55.3	54.9	55.6
Potential dilutive common shares (in shares)	0.3	0.2	0.3	0.2
Average number of diluted shares outstanding (in shares)	54.9	55.5	55.2	55.8
Basic (USD per share)	$ 1.47	$ 1.56	$ 4.05	$ 4.10
Diluted (USD per share)	$ 1.47	$ 1.56	$ 4.02	$ 4.08