COMMON STOCK AND STOCK-BASED COMPENSATION PLANS (Tables)

6 Months Ended

Jun. 30, 2016

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

A summary of the Company’s stock option and SARs activities and related information for the six months ended June 30, 2016, are as follows:


	Number of options and SAR units (1)			Weighted average exercise price		Weighted average remaining contractual term		Aggregate intrinsic- value
Outstanding as of December 31, 2015		2,406,455		$	18.15
Granted		—			—
Exercised		(520,059	)		14.74
Forfeited or expired		(28,300	)		17.83

Outstanding as of June 30, 2016 (2)		1,858,096		$	19.11		4.3	$	15,461,017

Exercisable as of June 30, 2016 (3)		1,312,950		$	19.96		3.7	$	9,944,437

(1)	The SAR units are convertible for a maximum number of shares of the Company’s common stock equal to 75% of the SAR units subject to the grant.

(2)	Due to the ceiling imposed on the SAR grants, the outstanding amount equals a maximum of 1,639,795 shares of the Company’s common stock issuable upon exercise.

(3)	Due to the ceiling imposed on the SAR grants, the exercisable amount equals a maximum of 1,192,123 shares of the Company’s common stock issuable upon exercise.

Summary of Restricted Stock Units Activity

A summary of the Company’s RSU activities and related information for the six months ended June 30, 2016, are as follows:


	Number of RSUs			Weighted Average Grant-Date Fair Value
Unvested as of December 31, 2015		234,000		$	19.89
Granted		338,100			20.79
Vested		(64,640	)		19.83
Forfeited or expired		(3,967	)		20.25

Unvested as of June 30, 2016		503,493		$	20.50

Expected to vest after June 30, 2016		463,214		$	20.49

Equity-Based Compensation Expense Included in Interim Condensed Consolidated Statements of Income

The following table shows the total equity-based compensation expense included in the interim condensed consolidated statements of income:


	Six months ended June 30,				Three months ended June 30,
	2016		2015		2016		2015
	(unaudited)		(unaudited)		(unaudited)		(unaudited)
Cost of revenue	$	114	$	77	$	54	$	42
Research and development, net		1,421		885		775		494
Sales and marketing		502		244		255		165
General and administrative		1,046		470		525		126

Total equity-based compensation expense	$	3,083	$	1,676	$	1,609	$	827

Assumptions Used to Estimate Fair Value of Stock Options Granted

The fair value for the Company’s stock options and SARs (other than share issuances in connection with the employee stock purchase plan, as detailed below) granted to employees was estimated using the following assumptions:


	Six months ended June 30, 2015		Three months ended June 30, 2015
	(unaudited)		(unaudited)
Expected dividend yield		0%		0%
Expected volatility		33%-49%		34%-49%
Risk-free interest rate		0.2%-2.0%		0.2%-2.0%
Expected forfeiture		10%		10%
Contractual term of up to		7 Years		7 Years
Suboptimal exercise multiple		2.1		2.1

Assumptions Used to Estimate Fair Value of Employee Stock Purchase Plan

The fair value for rights to purchase shares of common stock under the Company’s employee stock purchase plan was estimated on the date of grant using the following assumptions:


	Six months ended June 30,
	2016		2015
	(unaudited)		(unaudited)
Expected dividend yield		0%		0%
Expected volatility		36%-57%		36%
Risk-free interest rate		0.3%-0.5%		0.1%
Expected forfeiture		0%		0%
Contractual term of up to		24 months		24 months