Business Segment Information (Summary of Operations by Reportable Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended				12 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011		Dec. 31, 2011
Net revenues	$ 3,592.8		$ 3,910.1		$ 10,564.7		$ 11,275.3
Segment operating income	482.9		468.4		1,234.6		1,252.7
Gain (loss) on sale/asset impairment	0		(264.8)		4.5		(651.6)
Operating income	447.8		180.5		1,137.7		521.0
Climate Solutions [Member]
Net revenues	1,941.7		2,289.7		5,570.6		6,380.0
Segment operating income	247.0	[1]	264.3	[1]	579.6	[1]	631.7
Residential Solutions [Member]
Net revenues	558.6		504.4		1,632.7		1,569.8
Segment operating income	45.4		19.0		86.3		67.2
Industrial Technologies [Member]
Net revenues	701.6		696.5		2,180.6		2,108.9
Segment operating income	106.6		95.9		332.5		301.6
Security Technologies [Member]
Net revenues	390.9		419.5		1,180.8		1,216.6
Segment operating income	83.9		89.2		236.2		252.2
Unallocated Amount to Segment [Member]
Unallocated corporate expense	35.1		23.1		101.4		80.1
Hussmann Divestiture(Included in Climate Solutions) [Member]
Net revenues			281.8				781.7
Segment operating income			30.1				56.1
Gain (loss) on sale/asset impairment	$ 0	[1]	$ (264.8)	[1]	$ 4.5	[1]	$ (651.6)	[1]	$ (646.9)

[1] During the three and nine months ended September 30, 2011, the Company recorded a pre-tax loss on sale/asset impairment charge related to the Hussmann divestiture totaling $264.8 million and $651.6 million, respectively. During the nine months ended September 30, 2012, the Company recorded $4.5 million of purchase price adjustments related to the Hussmann sale. These amounts have been excluded from Segment operating income within the Climate Solutions segment as management excludes these charges from Operating income when making operating decisions about the business.