Reportable Business Segments (Details 4) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	$ 60.4	$ 53.5	$ 52.9
Residential Heating & Cooling [Member]
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	22.3	21.7	22.2
Commercial Heating & Cooling [Member]
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	7.7	8.0	8.0
Service Experts [Member]
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	2.0	2.2	1.9
Refrigeration [Member]
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	14.8	8.7	9.9
Corporate and Other [Member]
Summary of depreciation and amortization expense by business segment
Total depreciation and amortization	$ 13.6	$ 12.9	$ 10.9