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Aggregate dividends declared during the period for each share of common stock outstanding.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Dividends and Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands								3 Months Ended		6 Months Ended
	May 01, 2020	Feb. 21, 2020	Oct. 31, 2019	Aug. 02, 2019	May 03, 2019	Feb. 26, 2019	Nov. 02, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Dividends and Earnings Per Share
Cash dividend declared (in dollars per share)	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.06	$ 0.12	$ 0.12
Numerator:
Net income attributable to Primoris								$ 32,959	$ 17,787	$ 29,222	$ 19,734
Denominator:
Weighted average shares for computation of basic earnings per share								48,270	50,912	48,429	50,841
Dilutive effect of shares issued to independent directors								4		6	4
Dilutive effect of restricted stock units								394	316	347	363
Weighted average shares for computation of diluted earnings per share								48,668	51,228	48,782	51,208
(loss) earnings per share attributable to Primoris:
Basic earnings per share (in dollars per share)								$ 0.68	$ 0.35	$ 0.60	$ 0.39
Diluted earnings per share (in dollars per share)								$ 0.68	$ 0.35	$ 0.60	$ 0.39