Property and Equipment, Net

12 Months Ended

Dec. 31, 2018

Property Plant And Equipment And Asset Retirement Obligation [Abstract]

12. 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,	2018		2017
Equipment and vehicles	$	906,275	$	778,549
Quarry property		180,246		182,267
Land and land improvements		142,271		108,830
Buildings and leasehold improvements		108,884		82,601
Office furniture and equipment		65,680		56,894
Property and equipment		1,403,356		1,209,141
Less: accumulated depreciation and depletion		853,668		801,723
Property and equipment, net	$	549,688	$	407,418

Depreciation and depletion expense primarily included in cost of revenue in our consolidated statements of operations was $96.4 million, $63.8 million and $61.0 million for the years ended December 31, 2018, 2017 and 2016, respectively.

We have recorded liabilities associated with our legally required obligations to reclaim owned and leased quarry property and related facilities. As of December 31, 2018 and 2017, $4.4 million and $4.8 million, respectively, of our asset retirement obligations were included in accrued expenses and other current liabilities and $17.4 million and $17.7 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,	2018			2017
Beginning balance	$	22,527		$	21,936
Revisions to estimates		17			462
Liabilities settled		(1,790	)		(966	)
Accretion		1,038			1,095
Ending balance	$	21,792		$	22,527