Noncontrolling Interests (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Noncontrolling Interests
Revenue	$ 743,243	$ 661,558
Net income attributable to noncontrolling interests	3	989
Cash	93,474		$ 120,286
Accounts receivable	416,412		404,911
Contract assets	359,370		344,806
Accounts payable	258,962		235,972
Contract liabilities	$ 176,847		192,397
Carlsbad
Noncontrolling Interests
Ownership interest (as a percent)	50.00%
Carlsbad
Noncontrolling Interests
Revenue		4,024
Net income attributable to noncontrolling interests	$ 3	989
Distributions to partners	0	0
Capital contributions	0	$ 0
Cash	2,026		2,124
Due from Primoris	476
Accounts payable			38
Contract liabilities	$ 434		$ 425

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