Property Plant and Equipment

6 Months Ended

Jun. 30, 2019

Property, Plant and Equipment [Abstract]

Property, plant and equipment consisted of the following (in thousands):



	June 30, 2019			December 31, 2018			Estimated Useful Lives
Vehicles	$	44,620		$	45,050		3 - 5 years
Computer equipment and software	58,489			53,891			3 - 5 years
Leasehold improvements	27,977			26,401			2 - 15 years
Office furniture, fixtures and equipment	20,416			19,532			7 years
Build-to-suit lease building	—			8,247			10.5 years
Construction in process	3,076			2,975
Property, plant and equipment, gross	154,578			156,096
Accumulated depreciation and amortization	(92,978		)	(82,695		)
Property, plant and equipment, net	$	61,600		$	73,401

Property, plant and equipment, net includes approximately $21.6 million and $26.2 million of assets under finance or capital lease obligations at June 30, 2019 and December 31, 2018, respectively, net of accumulated amortization of $23.7 million and $22.2 million, respectively. Depreciation and amortization expense on all property, plant and equipment was $7.1 million and $6.2 million for the three months ended June 30, 2019 and 2018, respectively and $13.0 million and $12.4 million during the six months ended June 30, 2019 and 2018, respectively. Amortization expense relates to assets under finance or capital leases and is included in depreciation and amortization expense.

As a result of implementing ASU 2016-02, effective January 1, 2019 the Company's build-to-suit leasing arrangement was considered a sale-leaseback and is classified as an operating lease. This resulted in a reduction to property, plant and equipment, net of $6.1 million and a reduction of $6.6 million related the financing lease obligation within accrued expenses and other current liabilities and other long-term obligations. See Note 12 "Leases" for additional information related to the impact of adopting ASU 2016-02.