Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of changes in the carrying amount of goodwill, by reportable segment and other operating segments
Amortization expense		$ 14.0	$ 8.9	$ 4.1
Estimated amortization expense related to intangible assets
2021	$ 17.0	17.0
2022	15.0	15.0
2023	15.0	15.0
2024	15.0	15.0
2025	15.0	15.0
Aggregate carrying value of definite lived intangible assets	141.1	141.1	98.3
Goodwill	499.9	499.9	449.3	394.4
Impairment charges		0.4	0.8	0.0
Trademarks
Estimated amortization expense related to intangible assets
Trademarks	163.9	$ 163.9	153.4
Impairment charges	$ 0.7
Cues, Inc.
Estimated amortization expense related to intangible assets
Percentage fair value of each reporting unit exceeds carrying value	12.00%	12.00%
Goodwill	$ 47.9	$ 47.9
Patterson-Kelley, LLC
Estimated amortization expense related to intangible assets
Percentage fair value of each reporting unit exceeds carrying value	3.00%	3.00%
Goodwill	$ 14.2	$ 14.2
Minimum
Estimated amortization expense related to intangible assets
Percentage fair value of each reporting unit exceeds carrying value	75.00%	75.00%
Detection and Measurement reportable segment
Estimated amortization expense related to intangible assets
Trademarks	$ 58.1	$ 58.1
Aggregate carrying value of definite lived intangible assets	116.7	116.7
Goodwill	217.0	217.0	170.5	130.7
HVAC reportable segment
Estimated amortization expense related to intangible assets
Trademarks	96.7	96.7
Aggregate carrying value of definite lived intangible assets	24.4	24.4
Goodwill	136.6	136.6	132.5	117.4
Engineered Solutions reportable segment
Estimated amortization expense related to intangible assets
Trademarks	9.1	9.1
Goodwill	$ 146.3	$ 146.3	$ 146.3	$ 146.3

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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