Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 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
Income Statement Classifications	March 31, 2015		March 31, 2014
Cost of services and maintenance revenues	$	550	$	477
Research and development	13,257		12,780
Sales, marketing and services	10,696		16,016
General and administrative	9,708		11,428
Total	$	34,211	$	40,701

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	%