INFORMATION ON REPORTABLE SEGMENTS - Financial Data (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2022	Jul. 03, 2021	Jul. 02, 2022	Jul. 03, 2021
Revenues:
Revenues	$ 354.0	$ 296.6	$ 661.1	$ 583.8
Income:
Consolidated operating income	27.2	17.1	38.6	42.1
Special charges, net	0.1	0.6	0.1	0.8
Other operating expense	1.9	2.7	1.0	2.7
HVAC reportable segment
Revenues:
Revenues	218.7	185.4	411.8	361.0
Detection and Measurement reportable segment
Revenues:
Revenues	135.3	111.2	249.3	222.8
Operating Segments
Revenues:
Revenues	354.0	296.6	661.1	583.8
Income:
Consolidated operating income	48.1	37.3	78.3	79.6
Operating Segments | HVAC reportable segment
Revenues:
Revenues	218.7	185.4	411.8	361.0
Income:
Consolidated operating income	25.6	25.9	40.8	48.2
Special charges, net	0.1	0.2	0.1	0.2
Operating Segments | Detection and Measurement reportable segment
Revenues:
Revenues	135.3	111.2	249.3	222.8
Income:
Consolidated operating income	22.5	11.4	37.5	31.4
Special charges, net	0.0	0.4	0.0	0.6
Corporate expense
Income:
Corporate expense	16.4	13.6	33.0	28.0
Segment Reconciling Items
Income:
Long-term incentive compensation expense	2.5	3.3	5.6	6.0
Special charges, net	0.1	0.6	0.1	0.8
Other operating expense	$ 1.9	$ 2.7	$ 1.0	$ 2.7