Equity II (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period	$ 1,473.5	$ 1,463.5
Total comprehensive income	78.3	61.1
Stock-based compensation	2.8	2.5
Exercise of stock options	(18.3)	(16.4)
Income tax windfall from stock-based awards, net	8.6	3.5
Acquisition and surrender of common shares	(49.8)	(61.9)
Issuance of shares related to director's deferred compensation	0.2	0.8
Dividends to noncontrolling interest	(0.4)	(0.3)
Cash dividends declared	(24.4)	(23.0)
Equity, end of period	1,507.1	1,462.6
Hubbell Shareholders Equity [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period	1,467.8	1,459.2
Total comprehensive income	77.9	60.7
Stock-based compensation	2.8	2.5
Exercise of stock options	(18.3)	(16.4)
Income tax windfall from stock-based awards, net	8.6	3.5
Acquisition and surrender of common shares	(49.8)	(61.9)
Issuance of shares related to director's deferred compensation	0.2	0.8
Dividends to noncontrolling interest	0	0
Cash dividends declared	(24.4)	(23.0)
Equity, end of period	1,501.4	1,458.2
Noncontrolling Interest [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity, beginning of period	5.7	4.3
Total comprehensive income	0.4	0.4
Stock-based compensation	0	0
Exercise of stock options	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	(0.4)	(0.3)
Cash dividends declared	0	0
Equity, end of period	$ 5.7	$ 4.4