Stock-Based Incentive Plans (Tables)

9 Months Ended

Sep. 30, 2018

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

Movement in Outstanding Shares of Restricted Class A Common Stock and Weighted-Average Grant Date Fair Value Per Share

The following table details the movement in our outstanding shares of restricted class A common stock and the weighted-average grant date fair value per share:

	Restricted Class A Common Stock			Weighted-Average Grant Date Fair Value Per Share
Balance as of December 31, 2017		1,484,175		$	30.61
Granted		318,741			31.83
Vested		(404,241	)		28.89
Forfeited		(17,820	)		30.44
Balance as of September 30, 2018		1,380,855		$	31.40