Acquisitions - Additional Information (Detail) - USD ($)			3 Months Ended								12 Months Ended
	May 20, 2019	Jul. 31, 2017	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired											$ 33,196,000	$ 0	$ 216,308,000
Estimated amortization period											14 years
Goodwill			$ 436,679,000				$ 413,640,000				$ 436,679,000	413,640,000	422,185,000
Strategic transaction costs (Note 13)											4,400,000	421,000	4,225,000
Revenues			375,254,000	$ 351,014,000	$ 349,675,000	$ 326,038,000	$ 361,783,000	$ 331,096,000	$ 339,331,000	$ 325,894,000	1,401,981,000	1,358,104,000	1,196,809,000
Net income (loss)											136,440,000	124,150,000	26,027,000
Depreciation											26,500,000	26,900,000	28,000,000.0
Amortization primarily related to intangible assets											11,119,000	10,509,000
Americas
Business Acquisition [Line Items]
Goodwill			293,200,000								293,200,000
Revenues											915,118,000	854,287,000	736,847,000
Sierra Monitor Corporation
Business Acquisition [Line Items]
Common stock acquired (as a percent)	100.00%
Payments to Acquire Businesses, Net of Cash Acquired	$ 33,200,000
Future amortization expense, year one			1,000,000								1,000,000
Future amortization expense, year two			1,000,000								1,000,000
Future amortization expense, year three			1,000,000								1,000,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four			1,000,000								1,000,000
Future amortization expense, year five			1,000,000								1,000,000
Business Combination, Step Up To Fair Value Of Acquired Inventory As part Of Purchase Price Allocation	1,600,000
Goodwill	19,900,000
Revenues											13,500,000
Net income (loss)											(3,300,000)
Business Combination, Purchase Accounting Amortization For Intangible Assets And Inventory Step Up Excluded From Acquisitions											2,600,000
Business Acquisition, Transaction Costs			2,200,000								2,200,000
Net income related to acquiree adjusted to remove transaction costs											1,500,000
Sierra Monitor Corporation | Americas
Business Acquisition [Line Items]
Goodwill	$ 19,900,000
Globe Holding Company LLC
Business Acquisition [Line Items]
Common stock acquired (as a percent)		100.00%
Business Combination, Consideration Transferred		$ 215,000,000
Business Combination, Consideration Transferred, Working Capital Adjustments		1,400,000
Contingent consideration		$ 0
Estimated amortization period		5 years
Future amortization expense, year one			4,000,000								4,000,000
Future amortization expense, year three			3,000,000								3,000,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four			2,000,000								2,000,000
Future amortization expense, year five			2,000,000								2,000,000
Estimated future depreciation expense, year one			1,000,000								1,000,000
Estimated future depreciation expense, year two			1,000,000								1,000,000
Estimated future depreciation expense, year three			1,000,000								1,000,000
Estimated future depreciation expense, year four			1,000,000								1,000,000
Estimated future depreciation expense, year five			$ 1,000,000								$ 1,000,000
Goodwill		$ 74,500,000
Revenues												113,900,000	46,100,000
Net income (loss)												13,300,000	3,700,000
Depreciation												1,000,000.0	500,000
Amortization primarily related to intangible assets												4,100,000	1,700,000
Net income related to acquiree adjusted to remove transaction costs												$ 13,600,000	$ 4,900,000
Globe Holding Company LLC | Americas
Business Acquisition [Line Items]
Goodwill		$ 74,500,000
Technology related assets
Business Acquisition [Line Items]
Estimated amortization period											8 years
Technology related assets | Sierra Monitor Corporation
Business Acquisition [Line Items]
Estimated amortization period	5 years
Customer-related intangibles | Sierra Monitor Corporation
Business Acquisition [Line Items]
Estimated amortization period	10 years
Customer-related intangibles | Globe Holding Company LLC
Business Acquisition [Line Items]
Estimated amortization period		20 years
Stock Options And Restricted Stock Units | Sierra Monitor Corporation
Business Acquisition [Line Items]
Goodwill	$ 900,000
Performance Stock | Sierra Monitor Corporation
Business Acquisition [Line Items]
Share-based Payment Arrangement, Expense											$ 1,500,000