Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

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

Schedule of Stock-based Compensation Expense

Stock-based compensation expense associated with restricted participation and appreciation units, stock options and restricted stock was recorded in the following cost and expense categories consistent with the respective employee or service provider’s related cash compensation (in thousands):

	Year ended December 31,
	2015		2014		2013
Cost of revenue
Subscription and support	$	363	$	502	$	200
Professional services	349		337		171
Operating expenses
Research and development	1,924		1,757		762
Sales and marketing	1,727		1,241		799
General and administrative	6,637		3,548		1,438
Total	$	11,000	$	7,385	$	3,370

Schedule of Share-based Payment Award, Valuation Assumptions

The fair value of each option, participation and appreciation unit grant is estimated on the date of grant using the Black-Scholes option-pricing model. Expected volatility is based on historical volatilities for publicly traded stock options of comparable companies over the estimated expected life of the options. The expected term represents the period of time the options are expected to be outstanding and is based on the “simplified method.” We use the “simplified method” due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected life of the options. The risk-free interest rate is based on yields on U.S. Treasury STRIPS with a maturity similar to the estimated expected term of the options. The fair value of our participation and appreciation units and options was estimated assuming no expected dividends and the following weighted-average assumptions:

	Year ended December 31,
	2015	2014	2013
Expected term (in years)	6.1	5.0 - 10.0	6.1 - 10.0
Risk-free interest rate	1.35% - 1.93%	1.52% - 2.80%	1.00% - 2.89%
Expected volatility	42.35% - 47.07%	45.84% - 52.50%	51.09% - 53.84%
Forfeiture rate	4.82% - 5.21%	0% - 6.76%	0% - 6.02%

Schedule of Stock-Option Activity

The following table summarizes the option activity under the Plans for the year ended December 31, 2015:

	Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
					(in thousands)
Outstanding at December 31, 2014	6,089,938	$	9.63	7.8	$	30,066
Granted	1,718,332	14.36
Forfeited	131,846	13.75
Exercised	707,291	3.17
Outstanding at December 31, 2015	6,969,133	$	11.37	7.7	$	43,287
Exercisable at December 31, 2015	3,471,017	$	7.96	6.5	$	33,348

Schedule of Restricted Stock Activity

The following table summarizes the restricted stock activity under the Plan for the year ended December 31, 2015:

	Number of Shares		Weighted- Average Grant Date Fair Value		Aggregate Intrinsic Value
					(in thousands)
Outstanding at December 31, 2014	54,350		$	13.80	$	728
Granted	600,025		13.38
Forfeited	—		—
Vested	(54,350	)	13.80
Outstanding at December 31, 2015	600,025		$	13.38	$	10,542