CAPITAL STOCK (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Information with respect to options granted under all stock option plans for the year ended December 31, 2022 was as follows:


	Total Number of Options	Weighted- Average Exercise Price	Weighted- Average Remaining Contractual Life (years)	Aggregate Intrinsic Value (in thousands)
Options Outstanding at December 31, 2019	565,000	$7.57	1.17	571
Granted	—	—
Exercised	(319,000)	7.65
Forfeited or Expired	—	—
Options Outstanding at December 31, 2020	246,000	$7.48	0.44	$	1,358
Granted	—	—
Exercised	(246,000)	7.48
Forfeited or Expired	—	—
Options outstanding at December 31, 2021	—	$—	0	$	—
Granted	—	—
Exercised	—	—
Forfeited or Expired	—	—
Options outstanding at December 31, 2022	—	$—	0.00	$	—

Exercisable at:
December 31, 2020	246,000	$7.48	0.44	$1,358
December 31, 2021	—	$—	0.00	$—
December 31, 2022	—	$—	0.00	$—

Non-vested restricted stock and restricted stock units

Information with respect to non-vested time-based restricted stock units for the year ended December 31, 2022 was as follows:


	Number of Restricted Stock Units	Weighted- Average Grant-Date Fair Value	Shares Retained to Cover Statutory Minimum Withholding Taxes
Outstanding at December 31, 2019	2,087,933	$6.41
Granted	1,518,714	7.20
Vested	(1,193,553)	6.33	403,798
Forfeited	(298,215)	6.52
Outstanding at December 31, 2020	2,114,879	$7.01
Granted	458,469	29.01
Vested	(1,466,907)	6.83	492,008
Forfeited	(44,607)	10.43
Outstanding at December 31, 2021	1,061,834	$16.60
Granted	562,191	32.08
Vested	(673,285)	15.09	246,274
Forfeited	(162,523)	19.96
Outstanding at December 31, 2022	788,217	$28.24

Employee stock purchase plan

The following table sets forth the weighted-average key assumptions and fair value results for shares issued under the ESPP during the years ended December 31, 2022, 2021, and 2020:


	Year Ended December 31,
	2022	2021	2020
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.50%	0.08%	0.82%
Expected volatility	63.9%	62.9%	72.1%
Expected life (in years)	0.50	0.49	0.50
Weighted-average fair value of shares issued (per share)	$5.03	$3.77	$1.40

The following table sets forth the quantities and average prices of shares issued under the ESPP for the years ended December 31, 2022, 2021, and 2020:


	Year Ended December 31,
	2022	2021	2020
Shares issued under the ESPP	41,194	26,988	61,750
Average price of shares issued	$22.32	$29.95	$8.67

Allocated share-based compensation expense

December 31, 2022, 2021, and 2020, respectively (in thousands):


	Year Ended December 31,
	2022		2021		2020
Share-based compensation expense by type:

Time-based Restricted Stock Units	$	13,585	$	10,010	$	8,340
Performance-based Restricted Stock Units	2,779		3,575		2,211
ESPP	191		152		113
Total Share-based compensation expense	$	16,555	$	13,737	$	10,664

Stock-based compensation was included in the following captions in our consolidated statements of operations for the years ended December 31, 2022, 2021, and 2020, respectively (in thousands):


	Year Ended December 31,
	2022		2021		2020
Cost of revenues	$	2,063	$	1,800	$	1,339
Research and development expenses	2,289		1,620		1,725
Marketing and selling expenses	3,088		2,484		2,176
General and administrative expenses	9,115		7,833		5,424
Total	$	16,555	$	13,737	$	10,664