Decrease In Fair Value Of Reporting Units Considered For Impairment Calculation

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- Definition

Number of internal divisions.

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No definition available.

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- Definition

Number Of Reporting Units At Risk After Cushion Test

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No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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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

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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.

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Summary of Significant Accounting Policies - Goodwill (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2021 USD ($) division	Dec. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) unit	Dec. 31, 2019 USD ($)
Goodwill [Line Items]
Number of internal divisions \| division	2
Goodwill impairment loss	$ 0	$ 0
Decrease in fair value of reporting units considered for impairment		10.00%	10.00%
Goodwill	2,124,089,000	$ 2,121,014,000	$ 2,121,014,000	$ 2,022,675,000
Other intangible assets	415,122,000	$ 435,655,000	$ 435,655,000
Underground Utility and Infrastructure Solutions \| Two Canadian Pipeline Operating Businesses
Goodwill [Line Items]
Number of reporting units at risk after cushion test \| unit			2
Underground Utility and Infrastructure Solutions \| Two Canadian Pipeline Operating Businesses And United States Material Handling Services
Goodwill [Line Items]
Number of reporting units at risk after cushion test \| unit			3
Goodwill	100,900,000
Other intangible assets	18,500,000
Underground Utility and Infrastructure Solutions \| Specialized Industrial Services Business
Goodwill [Line Items]
Goodwill	303,100,000
Other intangible assets	$ 49,900,000