Segment Information - Revenue from External Customers by Products and Services (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue from External Customer [Line Items]
Net sales	$ 495,358	$ 446,728	$ 447,299	$ 398,262	$ 443,254	$ 381,694	$ 372,313	$ 330,692	$ 1,787,647	$ 1,527,953	$ 1,400,182
Revenues									$ 1,787,647	$ 1,527,953	$ 1,400,182
Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									100.00%	100.00%	100.00%
Firefighter Safety
Revenue from External Customer [Line Items]
Net sales									$ 684,224	$ 578,935	$ 526,326
Firefighter Safety | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									38.00%	38.00%	38.00%
Detection
Revenue from External Customer [Line Items]
Revenues									$ 634,915	$ 529,735	$ 461,779
Detection | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									36.00%	35.00%	33.00%
Industrial PPE and Other
Revenue from External Customer [Line Items]
Net sales									$ 468,508	$ 419,283	$ 412,077
Industrial PPE and Other | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									26.00%	27.00%	29.00%
Americas
Revenue from External Customer [Line Items]
Revenues									$ 1,235,594	$ 1,043,238	$ 908,068
Americas | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									100.00%	100.00%	100.00%
Americas | Firefighter Safety
Revenue from External Customer [Line Items]
Net sales									$ 501,676	$ 416,427	$ 354,426
Americas | Firefighter Safety | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									41.00%	40.00%	39.00%
Americas | Detection
Revenue from External Customer [Line Items]
Revenues									$ 419,312	$ 349,543	$ 292,058
Americas | Detection | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									34.00%	34.00%	32.00%
Americas | Industrial PPE and Other
Revenue from External Customer [Line Items]
Net sales									$ 314,606	$ 277,268	$ 261,584
Americas | Industrial PPE and Other | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									25.00%	26.00%	29.00%
International
Revenue from External Customer [Line Items]
Revenues									$ 552,053	$ 484,715	$ 492,114
International | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									100.00%	100.00%	100.00%
International | Firefighter Safety
Revenue from External Customer [Line Items]
Net sales									$ 182,548	$ 162,508	$ 171,900
International | Firefighter Safety | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									33.00%	34.00%	35.00%
International | Detection
Revenue from External Customer [Line Items]
Revenues									$ 215,603	$ 180,192	$ 169,721
International | Detection | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									39.00%	37.00%	34.00%
International | Industrial PPE and Other
Revenue from External Customer [Line Items]
Net sales									$ 153,902	$ 142,015	$ 150,493
International | Industrial PPE and Other | Sales | Product concentration risk
Revenue from External Customer [Line Items]
Concentration risk (percentage)									28.00%	29.00%	31.00%