SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Schedule of accumulated other comprehensive loss

The components of accumulated other comprehensive loss were as follows (in thousands):

	As of December 31,
	2014			2015
Foreign currency translation adjustment	$	(5,693	)	$	(7,159	)
Accumulated net unrealized loss on investments, net of tax	(691		)	(435		)
Total accumulated other comprehensive loss	$	(6,384	)	$	(7,594	)

Stock-based compensation expense for stock options and restricted stock

Stock-based compensation expense for stock options and restricted stock issued under equity incentive plans and stock purchases under the ESPP included in the Company’s results of operations were as follows (in thousands):

	Year Ended December 31,
	2013		2014		2015
Cost of revenues	$	4,553	$	4,759	$	5,815
Selling and marketing	4,954		3,776		5,114
Software development	7,244		5,095		5,712
General and administrative	24,798		14,637		17,896
Total stock-based compensation	$	41,549	$	28,267	$	34,537

Property and equipment, net

Property and equipment are stated at cost, net of accumulated depreciation and amortization. All repairs and maintenance costs are expensed as incurred. Depreciation and amortization are calculated on a straight-line basis over the following estimated useful lives of the assets:

Leasehold improvements	Shorter of lease term or useful life
Furniture and office equipment	Five to ten years
Research vehicles	Five to ten years
Computer hardware and software	Two to five years

Property and equipment consists of the following (in thousands):

	December 31,
	2014			2015
Leasehold improvements	$	42,026		$	49,752
Furniture, office equipment and research vehicles	31,016			38,129
Computer hardware and software	49,655			56,656
Property and equipment, gross	122,697			144,537
Accumulated depreciation and amortization	(48,944		)	(56,226		)
Property and equipment, net	$	73,753		$	88,311