Business Combinations (Details 2) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Pro forma results
Percentage of pro forma tax rate used in calculating taxes on income from continuing operations	39.00%	39.00%
Revenues	$ 395,778	$ 483,809
Income before provision for income taxes	180	16,168
Net income attributable to Primoris	$ 118	$ 9,499
Weighted average common shares outstanding:
Basic (in shares)	51,572	51,610
Diluted (in shares)	51,726	51,714
Earnings per share:
Basic (in dollars per share)	$ 0.00	$ 0.18
Diluted (in dollars per share)	$ 0.00	$ 0.18

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Represents the pro forma tax rate used in calculating taxes on income from continuing operations for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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- Definition

The pro forma number of diluted weighted average shares outstanding for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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- Definition

The pro forma number of basic weighted average shares outstanding for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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- Definition

The pro forma income from continuing operations before income taxes for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

No definition available.

+ Details

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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