Equity-Based Compensation Plans (Tables)

12 Months Ended

Dec. 31, 2019

The following table details our compensation expense and the related income tax benefit for the years ended December 31:

(in thousands)	2019		2018		2017
Employee equity-based compensation expense:
Performance stock awards	$	4,605	$	4,157	$	3,582
Restricted stock units		2,595		2,024		1,140
Deferred compensation stock equivalent units expense		72		213		657
Accelerated share-based termination benefits in connection with the merger		—		1,812		—
Total equity-based compensation expense	$	7,272	$	8,206	$	5,379

Total tax benefit recognized for shared-based payment awards	$	314	$	332	$	379

The following table presents the key inputs used in calculating the fair value of the PSAs and the resulting fair values:

	Year Ended December 31,
	2019			2018			2017
Stock price as of valuation date	$	35.01		$	54.00		$	43.60
Risk-free rate		2.47	%		2.46	%		1.61	%
Expected volatility		25.15	%		23.74	%		24.22	%
Expected dividend yield¹		—			2.96	%		3.44	%
Expected term (years)		3.00			3.00			3.00
Fair value of a performance share	$	37.87		$	75.37		$	53.85

¹	^{For 2019 assumes full dividend reinvestment}

The following table summarizes outstanding PSAs as of December 31 and the changes during each year:

	2019					2018					2017
(in thousands, except per share amounts)	Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value
Nonvested shares outstanding at January 1		142,238		$	63.91		200,631		$	39.19		203,788		$	32.59
Granted		142,066		$	37.87		67,747		$	75.37		78,033		$	53.85
Vested		(75,048	)	$	53.85		(121,058	)	$	30.02		(78,129	)	$	36.71
Forfeited		(13,249	)	$	45.35		(5,082	)	$	47.90		(3,061	)	$	34.68
Nonvested shares outstanding at December 31		196,007		$	50.15		142,238		$	63.91		200,631		$	39.19
Total grant date fair value of PSAs vested during the year	$	4,041				$	3,634				$	2,868
Total fair value of PSAs vested during the year	$	3,561				$	6,397				$	7,797
Aggregate intrinsic value of nonvested PSAs at December 31	$	8,481				$	4,500				$	10,011

The following table summarizes outstanding RSU awards as of December 31 and the changes during each year:

	2019					2018					2017
(in thousands, except per share amounts)	Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value		Shares			Weighted Average Grant Date Fair Value
Nonvested shares outstanding at January 1		72,020		$	47.66		67,871		$	32.87		71,420		$	31.61
Granted		104,488		$	36.80		49,193		$	49.96		26,507		$	43.64
Vested		(43,102	)	$	45.51		(41,350	)	$	26.33		(29,039	)	$	39.65
Forfeited		(5,935	)	$	40.26		(3,694	)	$	45.36		(1,017	)	$	31.63
Nonvested shares outstanding at December 31		127,471		$	39.83		72,020		$	47.66		67,871		$	32.87
Total grant date fair value of RSU awards vested during the year	$	1,961				$	1,089				$	1,151
Total fair value of RSU awards vested during the year	$	1,771				$	1,328				$	1,442
Aggregate intrinsic value of nonvested RSU awards at December 31	$	5,516				$	2,279				$	3,387