Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenues	$ 400,038	$ 264,086	$ 696,726	$ 488,035
Cost of revenues	(340,439)	(238,590)	(601,882)	(443,036)
Gross profit	59,599	25,496	94,844	44,999
General and administrative expense	(18,451)	(10,174)	(36,055)	(22,063)
Intangible asset amortization	(2,866)	(600)	(5,703)	(1,200)
Acquisition related costs	(139)	(262)	(612)	(262)
Other operating expense, net	(5,097)	(3,276)	(7,325)	(5,570)
Operating income	33,046	11,184	45,149	15,904
Interest income	24	291	123	655
Interest expense	(7,557)	(2,904)	(15,360)	(5,964)
Income before income taxes	25,513	8,571	29,912	10,595
Income tax expense	(7,248)	(706)	(8,432)	(869)
Net income	18,265	7,865	21,480	9,726
Less: Net income attributable to noncontrolling interests	(55)	(37)	(155)	(83)
Net income attributable to Sterling common stockholders	$ 18,210	$ 7,828	$ 21,325	$ 9,643
Net income per share attributable to Sterling common stockholders:
Basic (in dollars per share)	$ 0.65	$ 0.30	$ 0.77	$ 0.37
Diluted (in dollars per share)	$ 0.65	$ 0.29	$ 0.76	$ 0.36
Weighted average common shares outstanding:
Basic (in shares)	27,941	26,338	27,794	26,357
Diluted (in shares)	27,957	26,623	27,887	26,657