Total Equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period			$ 3,857.9		$ 3,857.9
Net income	$ 264.6	$ 256.7			689.8	$ 666.7
Other comprehensive income	(1.2)	$ 4.0			4.4	55.8
End of period	$ 4,117.8				4,117.8
Cash dividends declared (USD per share)	$ 1.42	$ 1.32	$ 2.84	$ 2.64
Total Hubbell Shareholders' Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	$ 3,911.9	$ 3,487.7	$ 3,847.9	$ 3,396.2	3,847.9	3,396.2
Net income	262.5	255.5	422.2	407.4
Other comprehensive income	(1.2)	4.0	5.6	51.8
Stock-based compensation	8.1	6.3	21.9	20.7
Acquisition/surrender of common shares	(0.7)	(2.1)	(235.1)	(245.9)
Cash dividends declared	(75.2)	(70.3)	(150.7)	(141.2)
Directors deferred compensation	0.2	0.2	0.1	(1.3)
End of period	4,105.6	3,681.3	3,911.9	3,487.7	4,105.6	3,681.3
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	0.6	0.6	0.6	0.6	0.6	0.6
End of period	0.6	0.6	0.6	0.6	0.6	0.6
Additional Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	2.7	0.0	6.4	2.6	6.4	2.6
Stock-based compensation	8.1	6.3	21.9	20.7
Acquisition/surrender of common shares	(0.7)	(2.1)	(25.7)	(22.0)
Directors deferred compensation	0.2	0.2	0.1	(1.3)
End of period	10.3	4.4	2.7	0.0	10.3	4.4
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	4,217.8	3,821.8	4,155.7	3,779.5	4,155.7	3,779.5
Net income	262.5	255.5	422.2	407.4
Acquisition/surrender of common shares			(209.4)	(223.9)	(209.4)	(223.9)
Cash dividends declared	(75.2)	(70.3)	(150.7)	(141.2)
End of period	4,405.1	4,007.0	4,217.8	3,821.8	4,405.1	4,007.0
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	(309.2)	(334.7)	(314.8)	(386.5)	(314.8)	(386.5)
Other comprehensive income	(1.2)	4.0	5.6	51.8
End of period	(310.4)	(330.7)	(309.2)	(334.7)	(310.4)	(330.7)
Non- controlling interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning of period	11.1	11.1	10.0	14.4	10.0	14.4
Net income	2.1	1.2	3.0	2.6
Dividends to noncontrolling interest	(1.0)	(0.6)	(1.9)	(5.9)
End of period	$ 12.2	$ 11.7	$ 11.1	$ 11.1	$ 12.2	$ 11.7