Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Depreciable lives of property and equipment

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 December 31, 2016 and December 31, 2015:

	December 31, 2016			December 31, 2015
Automobiles and trucks	$	2,525		$	2,749
Building and improvements	37,269			28,226
Construction equipment	165,023			159,963
Vessels and other equipment	88,659			89,485
Office equipment	7,125			6,057
	300,601			286,480
Less: accumulated depreciation	(181,293		)	(164,371		)
Net book value of depreciable assets	119,308			122,109
Construction in progress	543			5,649
Land	38,231			38,231
	$	158,082		$	165,989