Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

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

Summary of Restricted Stock Units Activity

RSU activity for the three months ended March 31, 2018 is summarized as follows:

	Number of Shares		Weighted Average Grant Date Fair Value
Outstanding at December 31, 2017	483,021		$	104.16
Granted	92,681		$	139.49
Settled	(75,142	)	$	109.85
Outstanding at March 31, 2018	500,560		$	109.95

Summary of Stock Option Activity

Stock option activity for the three months ended March 31, 2018 is summarized as follows:

	Number of Shares		Weighted Average Exercise Price
Outstanding at December 31, 2017	109,808		$	16.44
Exercised	(22,245	)	$	31.38
Outstanding at March 31, 2018	87,563		$	12.64