Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Total Stock-based Compensation Recognized by Income Statement Classification

The detail of the total stock-based compensation recognized by income statement classification is as follows (in thousands):

	Three Months Ended		Three Months Ended		Six Months Ended		Six Months Ended
Income Statement Classifications	June 30, 2015		June 30, 2014		June 30, 2015		June 30, 2014
Cost of services and maintenance revenues	$	742	$	704	$	1,292	$	1,181
Research and development	9,079		15,333		22,336		28,113
Sales, marketing and services	10,465		15,796		21,161		31,812
General and administrative	10,506		13,457		20,214		24,885
Total	$	30,792	$	45,290	$	65,003	$	85,991

Schedule of Assumptions Used to Value Nonvested Share Grants

The grant date fair value of the non-vested performance stock unit awards was determined through the use of a Monte Carlo simulation model, which utilized multiple input variables that determined the probability of satisfying the market condition requirements applicable to each award as follows:

	March 2015 Grant		March 2014 Grant
Expected volatility factor	0.14 - 0.29		0.19 - 0.38
Risk free interest rate	0.85	%	0.81	%
Expected dividend yield	0	%	0	%