Name:	prim_BusinessAcquisitionAmortizationPeriodGoodwillAndOtherIntangibleAssetsForIncomeTaxPurposes
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Represents the period of employment, non-competition and non-solicitation agreement with a key employee related to a business combination.

No definition available.

Name:	prim_BusinessAcquisitionPeriodOfEmploymentNonCompetitionAndNonSolicitationAgreement
Namespace Prefix:	prim_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the amount paid under the asset purchase agreement related to the intangible assets in a business combination.

No definition available.

Name:	prim_BusinessCombinationAmountPaidUnderAssetPurchaseAgreementKeyEmployeeContract
Namespace Prefix:	prim_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the amount of cash portion of consideration transferred in a business combination.

No definition available.

Name:	prim_BusinessCombinationConsiderationTransferredCash
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the amount of EBITDA (income before interest, taxes, depreciation and amortization) to be achieved by the acquiree in earnout target period to measure cash payment of potential contingent consideration.

No definition available.

Name:	prim_BusinessCombinationContingentConsiderationEBITDAForMeasuringPotentialCashPayment
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Represents the number of future potential payments in a business combination based on agreed upon contingencies.

No definition available.

Name:	prim_BusinessCombinationContingentConsiderationNumberOfFuturePotentialPayments
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Data Type:	xbrli:integerItemType
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Represents the amount of increase (decrease) in intangible assets in a business combination.

No definition available.

Name:	prim_BusinessCombinationIncreaseDecreaseInIntangibleAssets
Namespace Prefix:	prim_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents the amount of gross profit of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

No definition available.

Name:	prim_BusinessCombinationProFormaInformationGrossProfitOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	prim_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionLineItems
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Topic 805

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-Section 30

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-Topic 805

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-Paragraph 1

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Amount of (increase) decrease in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

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

-Publisher FASB

-Name Accounting Standards Codification

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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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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-Paragraph 1

-Subparagraph (c)(3)

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

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-Topic 805

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-Topic 805

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-Section 25

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Name:	us-gaap_BusinessCombinationContingentConsiderationLiability
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

This element represents the amount of revenue 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The amount of identifiable intangible assets recognized as of the acquisition date.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

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-Paragraph 1

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-Topic 805

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Namespace Prefix:	us-gaap_
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The amount of inventory recognized as of the acquisition date.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

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

-Name Accounting Standards Codification

-Topic 350

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-Section 50

-Paragraph 1

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-Topic 350

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-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Name:	us-gaap_Goodwill
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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Name:	us-gaap_GoodwillPeriodIncreaseDecrease
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Section 45

-Paragraph 13

-Subparagraph (b)

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