Share-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Expenses Associated with Share-Based Compensation Plans

The following table presents compensation expense associated with the Company’s share-based compensation plans:

	Three Months Ended September 30,				Nine Months Ended September 30,
(in thousands)	2017		2016		2017		2016
Expense:
RSUs	$	5,866	$	5,401	$	28,634	$	25,766
Stock options		69		68		203		203
Employee stock purchase plan		682		659		2,359		2,127
	$	6,617	$	6,128	$	31,196	$	28,096

Summary of RSU Activity

The following table summarizes RSU activity for the nine months ended September 30, 2017:

(in thousands, except weighted-average grant-date fair value)	Shares			Weighted-average grant-date fair value
Unvested at December 31, 2016		1,510		$	33.38
Granted during 2017		893		$	39.26
Vested during 2017		(957	)	$	34.53
Forfeited during 2017		(9	)	$	35.22
Unvested at September 30, 2017		1,437		$	36.25