Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2014

Stock-Based Compensation Expense

We record stock-based compensation expense (including stock options, restricted stock and employee stock purchase plan) to the same departments where cash compensation is recorded as follows (in thousands):

	Three months ended March 31,
	2014		2013
Costs of revenue	$	139	$	149
Selling and marketing		274		216
Research and development		269		131
General and administrative		366		279
Total stock-based compensation expense	$	1,048	$	775

Assumptions Used to Determine the Fair Value of Options Granted under Employee Stock-Based Compensation Arrangements

We estimate the fair value of options granted under our employee stock-based compensation arrangements at the date of grant using the Black-Scholes model using the following weighted-average assumptions as follows:

	Three months ended March 31,
	2014			2013
Dividend yield		None			None
Volatility		64	%		54	%
Risk-free interest rate		1.97	%		0.60	%
Expected life (years)		5.6			4.0