Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2018

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

Summary of stock option activity

A summary of stock option activity during the nine months ended September 30, 2018 is as follows (in thousands, except for per share amounts):

	Shares		Weighted- Average Exercise Price (in dollars per share)		Weighted- Average Contractual Life (in years)	Aggregate Intrinsic Value
Options outstanding at December 31, 2017	5,648		$	37.71
Granted	1,388		34.43
Exercised	(461	)	16.14
Canceled	(407	)	42.53
Expired	(409	)	52.04
Options outstanding at September 30, 2018	5,759		$	37.29	7.48	$	5,728
Options exercisable at September 30, 2018	3,121		$	36.56	6.38	$	5,728

Summary of restricted stock units activity

A summary of RSU activity during the nine months ended September 30, 2018 is as follows (in thousands, except for per share amounts):

	RSUs		Weighted- Average Grant Date Fair Value  (in dollars  per share)
RSUs Outstanding at December 31, 2017	147		$	36.69
Granted	221		37.83
Vested	(24	)	41.37
Forfeited	(82	)	37.37
RSUs Outstanding at September 30, 2018	262		$	37.00