Total Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity		$ 2,240.7			$ 2,240.7
Net income	$ 123.5		$ 96.6		305.0	$ 175.7
Other comprehensive (loss) income	(25.8)		$ 11.6		(20.4)	$ 7.0
Ending equity	$ 2,267.9				$ 2,267.9
Cash dividends declared (USD per share)	$ 1.05	$ 1.05	$ 0.98	$ 0.98	$ 2.10	$ 1.96
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	$ 0.6	$ 0.6	$ 0.6	$ 0.6	$ 0.6	$ 0.6
Ending equity	0.6	0.6	0.6	0.6	0.6	0.6
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	0.0	0.0	0.5	4.9	0.0	4.9
Stock-based compensation	5.6	11.1	3.9	9.5
Acquisition/surrender of common shares	1.9	11.2	4.5	14.0
Directors deferred compensation	0.2	0.1	0.1	0.1
Ending equity	3.9	0.0	0.0	0.5	3.9	0.0
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	2,538.1	2,560.0	2,415.4	2,393.7	2,560.0	2,393.7
Net income	122.0	180.2	95.8	77.7
Acquisition/surrender of common shares		145.2	10.5	2.7	145.2	13.2
Cash dividends declared	(56.5)	(56.9)	(53.4)	(53.3)
Ending equity	2,603.6	2,538.1	2,447.3	2,415.4	2,603.6	2,447.3
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	(325.4)	(330.8)	(333.8)	(329.2)	(330.8)	(329.2)
Other comprehensive (loss) income	(25.8)	5.4	11.6	(4.6)
Ending equity	(351.2)	(325.4)	(322.2)	(333.8)	(351.2)	(322.2)
Total Hubbell Shareholders' Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	2,213.3	2,229.8	2,082.7	2,070.0	2,229.8	2,070.0
Net income	122.0	180.2	95.8	77.7
Other comprehensive (loss) income	(25.8)	5.4	11.6	(4.6)
Stock-based compensation	5.6	11.1	3.9	9.5
Acquisition/surrender of common shares	1.9	156.4	15.0	16.7
Cash dividends declared	(56.5)	(56.9)	(53.4)	(53.3)
Directors deferred compensation	0.2	0.1	0.1	0.1
Ending equity	2,256.9	2,213.3	2,125.7	2,082.7	2,256.9	2,125.7
Non- controlling interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning equity	11.1	10.9	15.3	15.4	10.9	15.4
Net income	1.5	1.3	0.8	1.4
Dividends to noncontrolling interest	(1.6)	(1.1)	(0.9)	(1.5)
Ending equity	$ 11.0	$ 11.1	$ 15.2	$ 15.3	$ 11.0	$ 15.2