Property and Equipment

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment [Abstract]

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



	As of December 31,
	2015			2014
Computer equipment and software	$	120,886		$	85,171
Leasehold improvements	41,626			34,522
Furniture and fixtures	13,470			12,022
Machinery and equipment	447			447
Total property and equipment	176,429			132,162
Less: accumulated depreciation and amortization	(98,061		)	(49,864		)
Total property and equipment, net	$	78,368		$	82,298

Depreciation and amortization expense related to property and equipment and demonstration units during the years ended December 31, 2015, 2014 and 2013 was $61.2 million, $46.8 million and $19.2 million, respectively.

During the year ended December 31, 2015, we recognized $1.1 million in accelerated depreciation expense associated with changes in the estimated useful life of certain assets to be replaced in the first quarter of 2016.