Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Intangible assets
Gross Carrying Amount	$ 124,462	$ 125,221
Accumulated Amortization	99,546	93,596
Customer Relationships [Member]
Intangible assets
Gross Carrying Amount	87,072	87,577
Accumulated Amortization	$ 66,358	61,882
Customer Relationships [Member] \| Minimum
Intangible assets
Useful Life (in years)	3 years
Customer Relationships [Member] \| Maximum
Intangible assets
Useful Life (in years)	13 years
Trade Names [Member]
Intangible assets
Gross Carrying Amount	$ 28,930	28,930
Accumulated Amortization	$ 26,490	25,894
Trade Names [Member] \| Minimum
Intangible assets
Useful Life (in years)	5 years
Trade Names [Member] \| Maximum
Intangible assets
Useful Life (in years)	6 years
Technology And Software [Member]
Intangible assets
Useful Life (in years)	5 years
Gross Carrying Amount	$ 5,440	5,694
Accumulated Amortization	$ 4,739	4,321
Noncompete Agreements [Member]
Intangible assets
Useful Life (in years)	5 years
Gross Carrying Amount	$ 2,220	2,220
Accumulated Amortization	$ 1,670	1,447
Customer Contracts [Member]
Intangible assets
Useful Life (in years)	2 years
Gross Carrying Amount	$ 800	800
Accumulated Amortization	$ 289	$ 52

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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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)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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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
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- References

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