Special Charges, Net (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) employee	Dec. 31, 2019 USD ($) employee	Dec. 31, 2018 USD ($) employee
Special charges, net
Special charges, net	$ 3.2	$ 4.4	$ 3.7
Period for selling an asset	1 year
Period for settling liabilities	1 year
Restructuring charges
Employee termination costs	$ 1.8	3.1	3.7
Other cash costs, net	1.0	0.0	0.0
Non-cash asset write-downs	0.4	0.8	0.0
Total	3.2	4.4	3.7
Restructuring liabilities
Balance at beginning of year	1.7	1.1	0.6
Special charges	2.8	3.6	3.7
Utilization — cash	(2.8)	(2.9)	(3.2)
Currency translation adjustment and other	(0.2)	(0.1)	0.0
Balance at the end of year	1.5	1.7	1.1
Asset impairment charges	0.4	0.8	0.0
Facility Closing
Restructuring charges
Facility consolidation costs	0.0	0.5	0.0
Corporate
Special charges, net
Special charges, net	1.6	0.2	0.5
Restructuring charges
Employee termination costs	0.2	0.2	0.5
Other cash costs, net	1.0	0.0	0.0
Non-cash asset write-downs	0.4	0.0	0.0
Total	1.6	0.2	$ 0.5
Number of employees terminated | employee			6
Corporate | Facility Closing
Restructuring charges
Facility consolidation costs	$ 0.0	$ 0.0	$ 0.0
HVAC reportable segment
Restructuring charges
Number of employees terminated | employee	11	9	18
HVAC reportable segment | Reportable segments
Special charges, net
Special charges, net	$ 0.5	$ 0.8	$ 0.8
Restructuring charges
Employee termination costs	0.5	0.2	0.8
Other cash costs, net	0.0	0.0	0.0
Non-cash asset write-downs	0.0	0.5	0.0
Total	0.5	0.8	0.8
HVAC reportable segment | Reportable segments | Facility Closing
Restructuring charges
Facility consolidation costs	$ 0.0	0.1	0.0
Detection and Measurement reportable segment
Restructuring charges
Number of employees terminated | employee	5
Detection and Measurement reportable segment | Reportable segments
Special charges, net
Special charges, net	$ 0.3	0.0	0.0
Restructuring charges
Employee termination costs	0.3	0.0	0.0
Other cash costs, net	0.0	0.0	0.0
Non-cash asset write-downs	0.0	0.0	0.0
Total	0.3	0.0	0.0
Detection and Measurement reportable segment | Reportable segments | Facility Closing
Restructuring charges
Facility consolidation costs	0.0	$ 0.0	0.0
Engineered Solutions reportable segment
Restructuring charges
Number of employees terminated | employee		10
Engineered Solutions reportable segment | Reportable segments
Special charges, net
Special charges, net	0.0	$ 0.8	0.0
Restructuring charges
Employee termination costs	0.0	0.1	0.0
Other cash costs, net	0.0	0.0	0.0
Non-cash asset write-downs	0.0	0.3	0.0
Total	0.0	0.8	0.0
Engineered Solutions reportable segment | Reportable segments | Facility Closing
Restructuring charges
Facility consolidation costs	0.0	0.4	0.0
Other
Special charges, net
Special charges, net	0.8	2.6	2.4
Restructuring charges
Employee termination costs	0.8	2.6	2.4
Other cash costs, net	0.0	0.0	0.0
Non-cash asset write-downs	0.0	0.0	0.0
Total	0.8	$ 2.6	$ 2.4
Number of employees terminated | employee		339	239
Other | Facility Closing
Restructuring charges
Facility consolidation costs	$ 0.0	$ 0.0	$ 0.0