Property and Equipment (Tables)

3 Months Ended

Mar. 31, 2018

Property, Plant and Equipment [Abstract]

Summary of property and equipment

Depreciation is computed using the straight-line method over the estimated useful lives of the related assets for financial statement purposes, as follows:

Automobiles and trucks	3 to 5 years
Buildings and improvements	5 to 30 years
Construction equipment	3 to 15 years
Vessels and other equipment	1 to 15 years
Office equipment	1 to 5 years

The following is a summary of property and equipment at March 31, 2018 and December 31, 2017:

	March 31, 2018			December 31, 2017
Automobiles and trucks	$	1,863		$	1,940
Building and improvements	38,053			38,062
Construction equipment	153,309			166,203
Vessels and other equipment	94,945			85,113
Office equipment	7,092			8,039
	295,262			299,357
Less: accumulated depreciation	(192,480		)	(191,407		)
Net book value of depreciable assets	102,782			107,950
Construction in progress	4,003			245
Land	38,083			38,083
	$	144,868		$	146,278