CAPITAL STOCK (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Information with respect to options granted under all stock option plans for the year ended December 31, 2021 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, 2018	891,892	$8.46	1.55	—
Granted	—	—
Exercised	(70,006)	7.39
Forfeited or Expired	(256,886)	10.70
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	—	$—	0.00	$	—

Exercisable at:
December 31, 2019	565,000	$7.57	1.17	$571
December 31, 2020	246,000	$7.48	0.44	$1,358
December 31, 2021	—	$—	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, 2021 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, 2018	1,978,676	$5.12
Granted	1,320,536	7.33
Vested	(991,819)	5.16	307,005
Forfeited	(219,460)	5.98
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

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, 2021, 2020, and 2019:


	Year Ended December 31,
	2021	2020	2019
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	0.08%	0.82%	2.37%
Expected volatility	62.9%	72.1%	48.6%
Expected life (in years)	0.49	0.50	0.49
Weighted-average fair value of shares issued (per share)	$3.77	$1.40	$1.04

The following table sets forth the quantities and average prices of shares issued under the ESPP for the years ended December 31, 2021, 2020, and 2019:


	Year Ended December 31,
	2021	2020	2019
Shares issued under the ESPP	26,988	61,750	69,179
Average price of shares issued	$29.95	$8.67	$7.48

Allocated share-based compensation expense

December 31, 2021, 2020, and 2019, respectively (in thousands):


	Year Ended December 31,
	2020		2019		2018
Share-based compensation expense by type:

Time-based Restricted Stock Units	$	10,010	$	8,340	$	5,900
Performance-based Restricted Stock Units	3,575		2,211		1,964
ESPP	152		113		94
Total Share-based compensation expense	$	13,737	$	10,664	$	7,958

Stock-based compensation was included in the following captions in our consolidated statements of operations for the years ended December 31, 2021, 2020, and 2019, respectively (in thousands):


	Year Ended December 31,
	2021		2020		2019
Cost of revenues	$	1,800	$	1,339	$	617
Research and development expenses	1,620		1,725		1,068
Marketing and selling expenses	2,484		2,176		1,797
General and administrative expenses	7,833		5,424		4,476
Total	$	13,737	$	10,664	$	7,958