Segment Information - Percentage of Total Sales by Product Group (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenue from External Customer [Line Items]
Revenues	$ 381,694	$ 340,197	$ 1,084,699	$ 989,915
Breathing Apparatus
Revenue from External Customer [Line Items]
Revenues	91,977	70,790	254,878	217,094
Fixed Gas & Flame Detection
Revenue from External Customer [Line Items]
Revenues	87,746	79,786	251,321	204,825
Firefighter Helmets & Protective Apparel
Revenue from External Customer [Line Items]
Revenues	54,738	49,366	151,097	148,497
Portable Gas Detection
Revenue from External Customer [Line Items]
Revenues	39,481	41,853	121,116	118,102
Industrial Head Protection
Revenue from External Customer [Line Items]
Revenues	43,608	36,764	123,489	107,615
Fall Protection
Revenue from External Customer [Line Items]
Revenues	27,839	28,223	79,114	85,098
Other
Revenue from External Customer [Line Items]
Revenues	$ 36,305	$ 33,415	$ 103,684	$ 108,684
Revenue Benchmark | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%	100.00%
Revenue Benchmark | Breathing Apparatus | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	24.00%	21.00%	23.00%	22.00%
Revenue Benchmark | Fixed Gas & Flame Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	23.00%	23.00%	23.00%	21.00%
Revenue Benchmark | Firefighter Helmets & Protective Apparel | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	14.00%	15.00%	14.00%	15.00%
Revenue Benchmark | Portable Gas Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	10.00%	12.00%	11.00%	12.00%
Revenue Benchmark | Industrial Head Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	11.00%	11.00%	11.00%	11.00%
Revenue Benchmark | Fall Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	7.00%	8.00%	7.00%	9.00%
Revenue Benchmark | Other | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	11.00%	10.00%	11.00%	10.00%
Americas
Revenue from External Customer [Line Items]
Revenues	$ 276,082	$ 229,076	$ 754,116	$ 655,123
Americas | Breathing Apparatus
Revenue from External Customer [Line Items]
Revenues	70,482	46,095	185,490	146,329
Americas | Fixed Gas & Flame Detection
Revenue from External Customer [Line Items]
Revenues	62,134	53,787	167,269	127,014
Americas | Firefighter Helmets & Protective Apparel
Revenue from External Customer [Line Items]
Revenues	41,958	34,101	110,471	105,513
Americas | Portable Gas Detection
Revenue from External Customer [Line Items]
Revenues	28,358	29,186	85,815	80,281
Americas | Industrial Head Protection
Revenue from External Customer [Line Items]
Revenues	34,620	28,982	96,808	82,913
Americas | Fall Protection
Revenue from External Customer [Line Items]
Revenues	17,658	17,743	50,940	51,093
Americas | Other
Revenue from External Customer [Line Items]
Revenues	$ 20,872	$ 19,182	$ 57,323	$ 61,980
Americas | Revenue Benchmark | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%	100.00%
Americas | Revenue Benchmark | Breathing Apparatus | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	26.00%	20.00%	25.00%	22.00%
Americas | Revenue Benchmark | Fixed Gas & Flame Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	23.00%	23.00%	22.00%	19.00%
Americas | Revenue Benchmark | Firefighter Helmets & Protective Apparel | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	15.00%	15.00%	15.00%	16.00%
Americas | Revenue Benchmark | Portable Gas Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	10.00%	13.00%	11.00%	12.00%
Americas | Revenue Benchmark | Industrial Head Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	13.00%	13.00%	13.00%	13.00%
Americas | Revenue Benchmark | Fall Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	6.00%	8.00%	7.00%	8.00%
Americas | Revenue Benchmark | Other | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	7.00%	8.00%	7.00%	10.00%
International
Revenue from External Customer [Line Items]
Revenues	$ 105,612	$ 111,121	$ 330,583	$ 334,792
International | Breathing Apparatus
Revenue from External Customer [Line Items]
Revenues	21,495	24,695	69,388	70,765
International | Fixed Gas & Flame Detection
Revenue from External Customer [Line Items]
Revenues	25,612	25,999	84,052	77,811
International | Firefighter Helmets & Protective Apparel
Revenue from External Customer [Line Items]
Revenues	12,780	15,265	40,626	42,984
International | Portable Gas Detection
Revenue from External Customer [Line Items]
Revenues	11,123	12,667	35,301	37,821
International | Industrial Head Protection
Revenue from External Customer [Line Items]
Revenues	8,988	7,782	26,681	24,702
International | Fall Protection
Revenue from External Customer [Line Items]
Revenues	10,181	10,480	28,174	34,005
International | Other
Revenue from External Customer [Line Items]
Revenues	$ 15,433	$ 14,233	$ 46,361	$ 46,704
International | Revenue Benchmark | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	100.00%	100.00%	100.00%	100.00%
International | Revenue Benchmark | Breathing Apparatus | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	20.00%	22.00%	21.00%	21.00%
International | Revenue Benchmark | Fixed Gas & Flame Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	24.00%	23.00%	25.00%	23.00%
International | Revenue Benchmark | Firefighter Helmets & Protective Apparel | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	12.00%	14.00%	12.00%	13.00%
International | Revenue Benchmark | Portable Gas Detection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	11.00%	11.00%	11.00%	11.00%
International | Revenue Benchmark | Industrial Head Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	9.00%	7.00%	8.00%	7.00%
International | Revenue Benchmark | Fall Protection | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	10.00%	9.00%	9.00%	10.00%
International | Revenue Benchmark | Other | Product Concentration Risk
Revenue from External Customer [Line Items]
Concentration risk percentage	14.00%	14.00%	14.00%	15.00%