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Represents the period of meeting certain operating targets over which the contingent earnout is based, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

No definition available.

Name:	prim_BusinessCombinationContingentConsiderationArrangementsRangeOfOutcomesPeriod
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Period Type:	duration

Amount of land and buildings acquired, at the acquisition date.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount recognized as of the acquisition date for net working capital.

No definition available.

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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.

No definition available.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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Amount of liability recognized arising from contingent consideration in a business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 805
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-Section 50
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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount of capital lease obligation, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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