Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2016

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 June 30, 2016 and December 31, 2015:

	June 30, 2016			December 31, 2015
Automobiles and trucks	$	2,506		$	2,749
Building and improvements	31,374			28,226
Construction equipment	164,880			159,963
Vessels and other equipment	84,992			89,485
Office equipment	7,011			6,057
	290,763			286,480
Less: accumulated depreciation	(172,950		)	(164,371		)
Net book value of depreciable assets	117,813			122,109
Construction in progress	8,340			5,649
Land	38,231			38,231
	$	164,384		$	165,989