Business Combinations Intangible Assets Acquired (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Finite-Lived Intangible Assets, Gross [Abstract]
Aggregate Acquisitions	$ 45.2
Customer relationships
Finite-Lived Intangible Assets, Gross [Abstract]
Weighted Average Useful Life (in years)	7 years
Estimated Useful Life (in years)	7 years
Aggregate Acquisitions	$ 34.2
Non-compete agreements
Finite-Lived Intangible Assets, Gross [Abstract]
Weighted Average Useful Life (in years)	5 years
Estimated Useful Life (in years)	5 years
Aggregate Acquisitions	$ 0.3
Customer backlog
Finite-Lived Intangible Assets, Gross [Abstract]
Weighted Average Useful Life (in years)	1 year
Estimated Useful Life (in years)	1 year
Aggregate Acquisitions	$ 9.1
Trade name
Finite-Lived Intangible Assets, Gross [Abstract]
Weighted Average Useful Life (in years)	1 year
Estimated Useful Life (in years)	1 year
Aggregate Acquisitions	$ 0.4
Developed software
Finite-Lived Intangible Assets, Gross [Abstract]
Weighted Average Useful Life (in years)	3 years
Estimated Useful Life (in years)	3 years
Aggregate Acquisitions	$ 1.2

Useful life of finite-lived intangible assets acquired either individually or as part of a group of 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

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- References

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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