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Acquisitions Schedule of Intangible Assets Acquired as Part of Business Combination (Details) - USD ($) $ in Millions |  | 12 Months Ended
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Apr. 02, 2018 | Dec. 31, 2020
Minimum [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 4 years |
Minimum [Member] | Contractual customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 7 years 3 months 18 days
Minimum [Member] | Backlog |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 1 year
Minimum [Member] | Non-compete agreements |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 4 years
Maximum [Member] |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 7 years |
Maximum [Member] | Contractual customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 12 years 9 months
Maximum [Member] | Backlog |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 2 years 9 months
Maximum [Member] | Non-compete agreements |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life |  | 7 years
ECS |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Identifiable intangible assets | $ 195.0 |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life | 11 years |
ECS | Trademarks |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | $ 16.5 |
ECS | Contractual customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | 144.6 |
ECS | Backlog |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | $ 23.1 |
Finite-Lived Intangible Asset, Useful Life | 2 years 9 months |
ECS | Non-compete agreements |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | $ 10.3 |
ECS | Favorable contracts |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill | $ 0.5 |
Finite-Lived Intangible Asset, Useful Life | 5 years |
ECS | Minimum [Member] | Contractual customer relationships |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |
Finite-Lived Intangible Asset, Useful Life | 12 years 9 months |

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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 + Details
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