Revenue (Tables)

3 Months Ended

Mar. 31, 2020

Revenue from Contract with Customer [Abstract]

Schedule of disaggregation of revenue

	Three months ended March 31,
	2020		2019
Marine Segment
Construction	$	53,140	$	33,636
Dredging		30,899		26,167
Specialty Services		1,910		1,684
Marine segment contract revenues	$	85,949	$	61,487
Concrete Segment
Structural	$	21,236	$	11,491
Light Commercial		59,433		70,096
Other		2		31
Concrete segment contract revenues	$	80,671	$	81,618
Total contract revenues	$	166,620	$	143,105