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.

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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- 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

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
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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Plateau Acquisition - Schedule of Identifiable Intangible Assets (Details) - USD ($) $ in Thousands		6 Months Ended
	Oct. 02, 2019	Jun. 30, 2020
Business Acquisition [Line Items]
Weighted Average Life		24 years
Plateau Excavation
Business Acquisition [Line Items]
Fair Value	$ 218,600
Customer relationships
Business Acquisition [Line Items]
Weighted Average Life		25 years
Customer relationships \| Plateau Excavation
Business Acquisition [Line Items]
Weighted Average Life	25 years
Fair Value	$ 191,800
Trade name
Business Acquisition [Line Items]
Weighted Average Life		23 years
Trade name \| Plateau Excavation
Business Acquisition [Line Items]
Weighted Average Life	25 years
Fair Value	$ 24,800
Non-competition agreements
Business Acquisition [Line Items]
Weighted Average Life		5 years
Non-competition agreements \| Plateau Excavation
Business Acquisition [Line Items]
Weighted Average Life	5 years
Fair Value	$ 2,000