Property And Equipment (Tables)

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Abstract]

Summary of gross components of property and equipment

The following is a summary of the gross components of property and equipment (dollars in thousands):

		December 31,
	Estimated Useful Life	2018		2017
Vessels	15 to 30 years	$	2,185,409	$	2,083,267
ROVs, trenchers and ROVDrills	10 years	284,172		298,227
Machinery, equipment and leasehold improvements	5 to 15 years	316,197		314,278
Total property and equipment		$	2,785,778	$	2,695,772