Goodwill and Other Intangibles - Summary of Other Intangible Assets and Accumulated Amortization Balances (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Intangible Assets [Line Items]
Gross Carrying Value	$ 147,701	$ 155,264
Accumulated Amortization	(108,561)	(108,843)
Net Carrying Value	39,140	46,421
Net Carrying Value	39,140	46,421
Customer Relationships
Intangible Assets [Line Items]
Gross Carrying Value	92,257	97,815
Accumulated Amortization	(63,990)	(63,432)
Net Carrying Value	28,267	34,383
Technology
Intangible Assets [Line Items]
Gross Carrying Value	29,993	30,615
Accumulated Amortization	(24,423)	(24,075)
Net Carrying Value	5,570	6,540
Product Development Costs
Intangible Assets [Line Items]
Gross Carrying Value	20,781	22,164
Accumulated Amortization	(20,148)	(21,336)
Net Carrying Value	633	828
Tradenames
Intangible Assets [Line Items]
Net Carrying Value	$ 4,670	$ 4,670

Intangible assets.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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