Leasehold Improvements, Equipment, Land and Construction in Progress, net

12 Months Ended

Dec. 31, 2014

Leasehold Improvements, Equipment, Land and Construction in Progress, net

Leasehold Improvements, Equipment, Land and Construction in Progress, net

5. Leasehold Improvements, Equipment, Land and Construction in Progress, net

        Leasehold improvements, equipment, and construction in progress and related accumulated depreciation and amortization is as follows:

		December 31
	Ranges of Estimated Useful Life	2014			2013
Equipment	2 - 5 Years		33,576		$	30,563
Software	3 - 10 Years		24,104			19,063
Vehicles	4 Years		8,585			8,075
Other	10 Years		311			282
Leasehold improvements	Shorter of lease term or economic life up to 10 years		20,420			18,642
Construction in progress			2,098			5,212
			89,094			81,837
Less accumulated depreciation and amortization			(47,560	)		(38,202	)
			41,534			43,635
Land			1,250			1,250
Leasehold improvements, equipment, land and construction in progress, net		$	42,784		$	44,885

        Asset additions are recorded at cost, which includes interest on significant projects. Depreciation is provided in amounts sufficient to relate the cost of depreciable assets to operations over their estimated useful lives or over the terms of the respective leases, whichever is shorter, and depreciated principally on the straight-line basis. The costs and accumulated depreciation of assets sold or disposed of are removed from the accounts and the resulting gain or loss is reflected in earnings. Plant and equipment are reviewed for impairment when conditions indicate an impairment or future impairment; the assets are either written down or the useful life is adjusted to the remaining period of estimated useful life.

        Depreciation expense was $12,020, $10,403 and $6,672 in 2014, 2013 and 2012, respectively. Depreciation includes gain on sale of assets, net of loss on sale and abandonments of leasehold improvements and equipment, of $329 for the year ended December 31, 2014. For the years ended December 31, 2013 and 2012, depreciation includes net loss on sale and abandonments of leasehold improvements and equipment of $1,614 and $80, respectively. During the year ended December 31, 2013, we sold our equity interest in land for $2,322 and recognized a gain on sale of $1,191.