Equity II (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period			$ 1,473.5	$ 1,463.5
Total comprehensive income	102.4	63.2	245.2	198.0
Stock-based compensation			7.7	7.7
Stock Options Exercised			21.4	17.2
Income tax windfall from stock-based awards, net			11.3	4.0
Acquisition and surrender of common shares			(66.7)	(139.8)
Issuance of shares related to director's deferred compensation			0.2	0.8
Dividends to noncontrolling interest			(1.0)	(0.7)
Cash dividends declared			(73.0)	(68.2)
Equity, end of period	1,618.6	1,482.5	1,618.6	1,482.5
Hubbell Shareholders Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period			1,467.8	1,459.2
Total comprehensive income			243.8	196.2
Stock-based compensation			7.7	7.7
Stock Options Exercised			21.4	17.2
Income tax windfall from stock-based awards, net			11.3	4.0
Acquisition and surrender of common shares			(66.7)	(139.8)
Issuance of shares related to director's deferred compensation			0.2	0.8
Dividends to noncontrolling interest			0	0
Cash dividends declared			(73.0)	(68.2)
Equity, end of period	1,612.5	1,477.1	1,612.5	1,477.1
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period			5.7	4.3
Total comprehensive income			1.4	1.8
Stock-based compensation			0	0
Stock Options Exercised			0	0
Income tax windfall from stock-based awards, net			0	0
Acquisition and surrender of common shares			0	0
Issuance of shares related to director's deferred compensation			0	0
Dividends to noncontrolling interest			(1.0)	(0.7)
Cash dividends declared			0	0
Equity, end of period	$ 6.1	$ 5.4	$ 6.1	$ 5.4