(10)	Stock-Based Compensation

2009 Employee Stock Purchase Plan

The 2009 Employee Stock Purchase Plan (the “2009 ESPP”) allows for the issuance of 1,500,000 shares of our Class A common stock. The 2009 ESPP is intended to qualify as an “Employee Stock Purchase Plan” under Section 423 of the Internal Revenue Code of 1986, as amended, and is administered by the Compensation Committee of the Board of Directors.

Eligible employees are entitled to defer up to 10% of their base pay for the purchase of stock, up to $25,000 of fair market value of our Class A common stock annually. The purchase price is equal to 85% of the fair market value at the end of the purchase period.

Following is information regarding our 2009 ESPP:

Year Ended December 31,	2015
Shares purchased pursuant to 2009 ESPP		71,811
Weighted average per share price of shares purchased	$	90.04
Weighted average per share discount from market value for shares purchased	$	15.89

As of December 31,		2015
Shares available for purchase pursuant to 2009 ESPP			467,660

Compensation expense related to our 2009 ESPP is calculated based on the 15% discount from the per share market price on the date of grant.

2013 Stock Incentive Plan

Our 2013 Stock Incentive Plan, as amended, (the “2013 Plan”) allows for the grant of a total of 3.8 million shares in the form of stock appreciation rights, qualified stock options, nonqualified stock options and shares of restricted stock to our officers, key employees, directors and consultants. The 2013 Plan is administered by the Compensation Committee of the Board of Directors and permits accelerated vesting of outstanding awards upon the occurrence of certain changes in control. As of December 31, 2015, 1,520,910 shares of Class A common stock were available for future grants. As of December 31, 2015, there were no stock appreciation rights, qualified stock options or shares of restricted stock outstanding.

Restricted Stock Units (“RSUs”)

RSU grants vest over a period up to four years from the date of grant. RSU activity was as follows:

	RSUs			Weighted average grant date fair value
Balance, December 31, 2014		464,758		$	36.33
Granted		171,185			88.74
Vested		(216,833	)		62.74
Forfeited		(8,036	)		57.73
Balance, December 31, 2015		411,074			59.13

We granted 34,903 time-vesting RSUs to members of our Board of Directors and employees in 2015. Each grant entitles the holder to receive shares of our Class A common stock upon vesting. A quarter of the RSUs vest on each of the four anniversaries of the grant date for employees and vests quarterly for our Board of Directors, over their service period.

Certain key employees were granted 85,290 performance and time-vesting RSUs in 2015. The RSUs entitled the holder to receive shares based on attaining various target levels of operational performance. Based on the levels of performance achieved in 2015, a weighted average attainment level of 72% for these RSUs was met. These RSUs will vest over four years from the grant date.

Twelve senior executives were also granted 50,992 long-term RSUs which vest based on attaining or exceeding a specified target level of adjusted net income per share in any fiscal year ending between December 31, 2015 and December 31, 2018. The RSUs will vest on the date the target level is certified.

Stock Options

Stock options become exercisable over a period of up to five years from the date of grant with expiration dates up to ten years from the date of grant and at exercise prices of not less than market value, as determined by the Board of Directors. The expiration date of options granted is six years.

Stock option activity was as follows:

	Shares subject to options			Weighted average exercise price		Aggregate intrinsic value (in millions)		Weighted average remaining contractual term (in years)
Balance, December 31, 2014		6,834		$	6.79	$	0.5		0.8
Granted		—			—
Forfeited		—			—
Expired		(2,000	)		3.23
Exercised		(4,834	)		8.27
Balance, December 31, 2015		—			—		—		—
Exercisable, December 31, 2015		—			—		—		—

Stock-Based Compensation

As of December 31, 2015, unrecognized stock-based compensation related to outstanding, but unvested RSUs was $10.3 million, which will be recognized over the remaining weighted average vesting period of 1.3 years.

Certain information regarding our stock-based compensation was as follows:

Year Ended December 31,	2015		2014		2013
Per share intrinsic value of non-vested stock granted	$	88.74	$	68.99	$	43.13
Weighted average per share discount for compensation expense recognized under the 2009 ESPP		15.89		11.92		8.81
Total intrinsic value of stock options exercised (in millions)		0.5		3.1		8.7
Fair value of non-vested stock that vested during the period (in millions)		19.3		18.9		8.4
Stock-based compensation recognized in Consolidated Statements of Operations, as a component of selling, general and administrative expense (in millions)		11.9		7.4		6.6
Tax benefit recognized in Consolidated Statements of Operations (in millions)		4.2		2.6		2.3
Cash received from options exercised and shares purchased under all share-based arrangements (in millions)		6.5		4.9		5.2
Tax deduction realized related to stock options exercised (in millions)		7.6		8.4		6.5