Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2014

Assumptions Used to Determine Fair Market Value of Stock Options Granted

The assumptions used to determine the fair market value of the stock options granted during the three months ended March 31, 2014 and 2013 were as follows:


	2014			2013
Weighted average fair value of options granted	$	12.95		$	1.66
Average risk-free interest rate		2.02	%		1.10	%
Expected stock price volatilities_(a)		50.7	%		53.8	%
Dividend yield		None			None
Expected stock option life		6.31			6.06

There was no active external or internal market for the Company’s shares until April of 2014. Thus, it was not possible to estimate the expected volatility of the Company’s share price in estimating fair value of options granted. As a substitute for such volatility, the Company used the historical volatility of comparable companies.

Summary of Stock Option Activity

Stock option awards as of December 31, 2013 and March 31, 2014, and changes during the three months ended March 31, 2014, were as follows:


	Options			Weighted Average Exercise Price		Average Intrinsic Value (thousands)		Weighted Average Exercise Term (years)
Outstanding at December 31, 2013		7,669,553		$	4.08	$	56,844		8.29
Granted		1,598,990			13.70
Forfeited		(166,876	)		5.86
Exercised		(418,463	)		3.38

Outstanding at March 31, 2014		8,683,204			5.85		131,628		8.40

Vested and expected to vest March 31, 2014		7,442,473			5.67		114,077		8.38
Exercisable at March 31, 2014		3,368,799		$	3.80	$	57,945		8.02