Total Equity Equity III (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			$ 1,935.7	$ 1,914.8
Total comprehensive income	$ 95.9	$ 100.7	137.9	169.3
Stock-based compensation			7.0	6.3
Exercise of stock options				0.7
Income tax windfall from stock-based awards, net			1.6	6.2
Repurchase/surrender of common shares			(79.3)	(31.1)
Issuance of shares related to directors’ deferred compensation			0.2	0.5
Dividends to noncontrolling interest			(1.7)	(1.3)
Cash dividends declared			(64.9)	(59.2)
EQUITY, JUNE 30	1,936.5	2,006.2	1,936.5	2,006.2
Hubbell Shareholders’ Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			1,927.1	1,906.4
Total comprehensive income			135.7	167.6
Stock-based compensation			7.0	6.3
Exercise of stock options				0.7
Income tax windfall from stock-based awards, net			1.6	6.2
Repurchase/surrender of common shares			(79.3)	(31.1)
Issuance of shares related to directors’ deferred compensation			0.2	0.5
Cash dividends declared			(64.9)	(59.2)
EQUITY, JUNE 30	1,927.4	1,997.4	1,927.4	1,997.4
Noncontrolling interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
EQUITY, JANUARY 1			8.6	8.4
Total comprehensive income			2.2	1.7
Dividends to noncontrolling interest			(1.7)	(1.3)
EQUITY, JUNE 30	$ 9.1	$ 8.8	$ 9.1	$ 8.8