Construction Joint Ventures - SEMA Financials (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Equity Method Investments [Line Items]
Revenues	$ 296,688	$ 223,949
Operating income	12,103	4,720
Net income attributable to Sterling common stockholders	$ 3,115	1,815
RLW \| Joint Ventures
Schedule of Equity Method Investments [Line Items]
Ownership percentage	51.00%
SEMA Construction Inc \| Joint Ventures
Schedule of Equity Method Investments [Line Items]
Ownership percentage	49.00%
Revenues	$ 4,064	602
Operating income	296	38
Net income attributable to Sterling common stockholders	$ 299	$ 38

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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