
						Weighted
		Weighted				Average
		Average		Aggregate		Remaining
		Exercise		Intrinsic		Contractual
	Shares	Price		Value		Term (Years)
Outstanding as of December 31, 2020	357,033	$	49.93
Granted	205,800		35.30
Cancelled, expired or forfeited	(16,239)		44.38
Outstanding as of December 31, 2021	546,594	$	44.59	$	—	6.9
Exercisable as of December 31, 2021	283,329	$	48.52	$	—	5.3

Schedule of components of pre-tax share-based compensation expense (primarily included in Selling, general and administrative expenses in our consolidated statements of operations) and related tax benefits


$s in thousands	2021		2020		2019
Share-based compensation from:
Stock options	$	1,201	$	725	$	575
Restricted stock		2,719		2,032		1,662
Restricted stock units (1)		2,758		3,810		6,193
Performance stock units (2)		1,211		1,266		831
Total share-based compensation		7,889		7,833		9,261
Income tax benefit		(1,162)		(2,115)		(3,098)
Share-based compensation, net of tax	$	6,727	$	5,718	$	6,163

(1)

Share-based compensation from restricted stock units for the years ended December 31, 2020 and 2019 includes $605,000 and $3.7 million, respectively, of compensation expense related to the accelerated vesting of restricted stock unit awards upon the termination of former employees of NRC subsequent to the NRC Merger in accordance with change-in-control provisions of their respective employment agreements. Share-based compensation from restricted stock units for the year ended December 31, 2021 and 2020 also includes $434,000 and $405,000, respectively, of compensation expense related restricted stock unit awards granted to certain employees identified as critical to the successful integration of NRC. Share-based compensation from these awards is attributable entirely to the NRC Merger therefore the Company has classified this portion of share-based compensation expense as business development and integration expenses within Selling, general and administrative expenses in our consolidated statements of operations.

(2)

Share-based compensation from performance stock units for the year ended December 31, 2021 includes a benefit of $23,000 to compensation expense related to the expiration of milestone-based performance stock unit awards granted to certain employees identified as critical to the successful integration of NRC. Share-based compensation from performance stock units for the year ended December 31, 2020 includes $173,000 of compensation expense related to achievement of milestone-based performance stock unit awards granted to certain employees identified as critical to the successful integration of NRC. Share-based compensation from these awards is attributable entirely to the NRC Merger therefore the Company has classified this portion of share-based compensation expense as business development and integration expenses within Selling, general and administrative expenses in our consolidated statements of operations.

Schedule of assumptions for determining the fair value for PSU awards using Monte Carlo simulation models


	2020			2019
Stock price on grant date	$	32.89		$	58.40
Expected term		2.5	years		3.0	years
Expected volatility		40.6	%		30.0	%
Risk-free interest rate		0.2	%		2.5	%
Expected dividend yield		—	%		1.1	%