Property and Equipment, Net

12 Months Ended

Dec. 31, 2017

Property, Plant and Equipment and Asset Retirement Obligation [Abstract]

Property and Equipment, net

Balances of major classes of assets and allowances for depreciation and depletion are included in property and equipment, net in the consolidated balance sheets as follows (in thousands):



December 31,	2017		2016
Equipment and vehicles	$	778,549	$	756,602
Quarry property	182,267		174,839
Land and land improvements	108,830		110,999
Buildings and leasehold improvements	82,601		82,762
Office furniture and equipment	56,894		56,381
Property and equipment	1,209,141		1,181,583
Less: accumulated depreciation and depletion	801,723		774,933
Property and equipment, net	$	407,418	$	406,650

Depreciation and depletion expense primarily included in cost of revenue in our consolidated statements of operations was $63.8 million for the year ended December 31, 2017 and was $61.0 million for both years ended December 31, 2016 and 2015.

Capitalized interest costs related to certain self-constructed assets were immaterial for the years ended December 31, 2017, 2016 and 2015 and were included in investments in affiliates and property and equipment in the consolidated balance sheets.

We have recorded liabilities associated with our legally required obligations to reclaim owned and leased quarry property and related facilities. As of December 31, 2017 and 2016, $4.8 million and $1.9 million, respectively, of our asset retirement obligations were included in accrued expenses and other current liabilities and $17.7 million and $20.1 million, respectively, were included in other long-term liabilities in the consolidated balance sheets.

The following is a reconciliation of these asset retirement obligations (in thousands):



Years Ended December 31,	2017			2016
Beginning balance	$	21,936		$	26,558
Revisions to estimates	462			(2,058		)
Liabilities settled	(966		)	(3,806		)
Accretion	1,095			1,242
Ending balance	$	22,527		$	21,936