PROPERTY, PLANT AND EQUIPMENT (Tables)

12 Months Ended

Dec. 31, 2017

Property Plant And Equipment [Abstract]

Summary of Property Plant Equipment by Asset Category

A summary of property, plant and equipment by asset category is as follows:

	December 31,
	2017			2016
	(In thousands)
Marine Vessels	$	1,799,177		$	1,789,942
Construction Equipment		498,621			474,128
Buildings		157,340			152,584
All other		161,855			148,805
Construction in Progress		34,094			20,720
Total Cost		2,651,087			2,586,179
Accumulated Depreciation		(985,273	)		(898,878	)
Net Book Value	$	1,665,814		$	1,687,301