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Revenue Recognition (Revenue by Business Segment by Geography) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 1.5	$ 1.3	$ 2.6	$ 2.9
Revenue, Net	1,099.1	1,175.4	1,889.4	2,010.2
Residential Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	689.1	716.0	1,154.6	1,169.7
Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	261.3	252.1	434.7	431.2
Refrigeration [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	148.2	205.5	297.1	405.5
Revenue, Net	148.7	207.3	300.1	409.3
Equipment Sales [Member] \| Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	226.6	218.7	370.2	370.2
Commercial Heating and Cooling [Member] \| Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	34.7	33.4	64.5	61.0
International [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	69.0	94.2	128.3	199.7
International [Member] \| Residential Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	0.0	0.0	0.0	0.0
International [Member] \| Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	0.3	0.7	0.5	0.8
International [Member] \| Refrigeration [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	68.7	93.5	127.8	198.9
CANADA
Disaggregation of Revenue [Line Items]
Revenue, Net	63.8	75.1	112.8	122.9
CANADA \| Residential Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	41.9	52.4	74.3	82.6
CANADA \| Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	21.9	21.6	37.8	38.3
CANADA \| Refrigeration [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	0.0	1.1	0.7	2.0
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue, Net	966.3	1,006.1	1,648.3	1,687.6
UNITED STATES \| Residential Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	647.2	663.6	1,080.3	1,087.1
UNITED STATES \| Commercial Heating and Cooling [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	239.1	229.8	396.4	392.1
UNITED STATES \| Refrigeration [Member]
Disaggregation of Revenue [Line Items]
Revenue, Net	$ 80.0	$ 112.7	$ 171.6	$ 208.4