Property and Equipment

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property and Equipment

6.Property and Equipment

The following is a summary of property and equipment at December 31, 2020 and December 31, 2019:

	December 31,		December 31,
	2020		2019
Automobiles and trucks	$	2,379	$	2,161
Building and improvements		44,324		44,278
Construction equipment		142,661		153,147
Vessels and other equipment		79,499		84,022
Office equipment		5,577		8,652
		274,440		292,260
Less: Accumulated depreciation		(186,615)		(196,973)
Net book value of depreciable assets		87,825		95,287
Construction in progress		1,809		1,198
Land		35,863		35,863
	$	125,497	$	132,348

For the years ended December 31, 2020, 2019 and 2018, depreciation expense was $21.8 million, $23.5 million and $28.4 million, respectively. Substantially all depreciation expense is included in the cost of contract revenue in the Company’s Consolidated Statements of Operations. Substantially all of the assets of the Company are pledged as collateral under the Company’s Credit Agreement (as defined in Note 11).

Substantially all of the Company’s long-lived assets are located in the United States.