Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 187,931	$ 217,380
Accumulated Amortization	(126,236)	(119,944)
Impairment		(28,794)
Net Carrying Amount	61,695	68,642
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Amount	112,596	116,101
Accumulated Amortization	(79,208)	(75,649)
Impairment		(2,206)
Net Carrying Amount	$ 33,388	38,246
Customer relationships \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	5 years
Customer relationships \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	18 years
Software/Technology
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 52,013	77,326
Accumulated Amortization	(25,726)	(23,519)
Impairment		(25,874)
Net Carrying Amount	$ 26,287	27,933
Software/Technology \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	3 years
Software/Technology \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	15 years
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 12,624	12,833
Accumulated Amortization	(12,350)	(12,162)
Impairment		(212)
Net Carrying Amount	$ 274	459
Covenants not to compete \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	2 years
Covenants not to compete \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	5 years
Other
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 10,698	11,120
Accumulated Amortization	(8,952)	(8,614)
Impairment		(502)
Net Carrying Amount	$ 1,746	$ 2,004
Other \| Minimum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	2 years
Other \| Maximum
Finite-Lived Intangible Assets [Line Items]
Useful Life (Years)	12 years

Finite-Lived Intangible Assets, Accumulated Impairment

No definition available.

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- Definition

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.

+ References

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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