Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation Expense and Related Tax Benefit

Total stock-based compensation expense and the related tax benefit were as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
In thousands	2020		2019		2020		2019
Stock options	$	452	$	389	$	1,445	$	1,413
Restricted stock units	4,399		6,734		18,575		19,178
Unrestricted stock awards	206		158		618		473
Phantom stock units	582		822		2,075		2,265
Total stock-based compensation	$	5,639	$	8,103	$	22,713	$	23,329
Related tax benefit	$	1,070	$	1,443	$	4,257	$	4,161

Employee Stock Options Activity

A summary of our stock option activity is as follows:

	Shares	Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value		Weighted Average Grant Date Fair Value
	(in thousands)			(years)	(in thousands)
Outstanding, January 1, 2019	895	$	47.93	6.2	$	4,806
Granted	76	76.55					$	26.20
Exercised	(117)	40.10			2,745
Forfeited	(8)	67.38
Expired	(11)	66.24
Outstanding, September 30, 2019	835	$	51.22	5.5	$	19,190
Outstanding, January 1, 2020	458	$	56.38	7.0	$	12,641
Granted	80	84.38					$	26.21
Exercised	(49)	50.90			1,189
Forfeited	(5)	83.80
Outstanding, September 30, 2020	484	$	61.30	7.0	$	3,816
Exercisable, September 30, 2020	319	$	52.68	6.0	$	3,764

Stock Options, Valuation Assumptions

The weighted average assumptions used to estimate the fair value of stock options granted and the resulting weighted average fair value are as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Expected volatility	41.5	%	31.7	%	32.1	%	31.7	%
Risk-free interest rate	0.3	%	1.7	%	1.3	%	1.7	%
Expected term (years)	5.3		6.1		5.3		6.1

Restricted Stock Units Award Activity

The following table summarizes restricted stock unit activity:

In thousands, except fair value	Number of Restricted Stock Units	Weighted Average Grant Date Fair Value		Aggregate Intrinsic Value
Outstanding, January 1, 2019	817
Granted	334	$	62.04
Released (1)	(435)			$	26,852
Forfeited	(53)
Outstanding, September 30, 2019	663
Outstanding, January 1, 2020	684	$	64.38
Granted	209	83.34
Released (1)	(338)	65.01		$	21,947
Forfeited	(23)	69.12
Outstanding, September 30, 2020	532	71.45
Vested but not released, September 30, 2020	9			$	549

(1)     Shares released is presented gross of shares netted for employee payroll tax obligations.

Restricted Stock Units, Valuation Assumptions

The weighted average assumptions used to estimate the fair value of performance-based restricted stock units granted with a service and market condition and the resulting weighted average fair value are as follows:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2020			2019			2020			2019
Expected volatility	52.6		%	33.4		%	38.2		%	31.4		%
Risk-free interest rate	0.2		%	1.8		%	1.5		%	2.5		%
Expected term (years)	2.3			2.5			1.8			1.6
Weighted average fair value	$	61.45		$	72.18		$	93.05		$	61.25