Property and Equipment (Notes)

6 Months Ended

Jun. 30, 2015

Property, Plant and Equipment [Abstract]

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



	As of June 30, 2015			As of December 31, 2014
Computer equipment and software	$	98,745		$	85,171
Leasehold improvements	37,611			34,522
Furniture and fixtures	12,759			12,022
Machinery and equipment	447			447
Total property and equipment	149,562			132,162
Less: accumulated depreciation	(75,124		)	(49,864		)
Total property and equipment, net	$	74,438		$	82,298

Depreciation and amortization expense related to property and equipment and demonstration units during the three months ended June 30, 2015 and 2014 was $15.3 million and $10.2 million, respectively. Depreciation and amortization expense related to property and equipment and demonstration units during the six months ended June 30, 2015 and 2014 was $29.5 million and $19.9 million, respectively.

During the three months ended June 30, 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.