STOCK-BASED COMPENSATION (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

For 2022, 2021, and 2020, the fair value of each option grant was estimated using the Black-Scholes option-pricing model, using the following assumptions:

	Years Ended December 31,
	2022	2021	2020
Expected option life (years)	5.50 - 6.25	5.50 - 6.25	5.50 - 6.25
Risk-free interest rate	1.71% - 2.83%	0.68% - 1.39%	0.31% - 1.63%
Expected stock price volatility	48.4% - 50.0%	48.2% - 49.5%	49.2% - 51.2%
Dividend yield	—	—	—

Summary of Stock option and restricted stock activity

A summary of stock option activity under the 2022 Plan and Inducement Grants during the years ended December 31, 2022, 2021, and 2020 is presented below:

				Weighted		Weighted
				Average		Average
		Weighted		Grant-		Remaining
(in thousands, except per share and	Option	Average		date		Term	Aggregate
remaining term data)	Shares	Exercise Price		Fair Value		(years)	Intrinsic Value
Outstanding December 31, 2019	757	$	54.21			7.2	$	6,761
Granted	231		30.29	$	14.39
Exercised	(8)		36.81					216
Forfeited	(44)		54.54
Expired	—		—
Outstanding December 31, 2020	936	$	48.44			7.1	$	372
Granted	168		33.09	$	15.71
Exercised	(42)		40.25					552
Forfeited	(19)		59.84
Expired	(55)		55.59
Outstanding at December 31, 2021	988	$	45.56			6.6	$	6,786
Granted	36		34.52	$	16.82
Exercised	(23)		30.03					153
Forfeited	(47)		36.91
Expired	(47)		55.07
Outstanding at December 31, 2022	907	$	45.47			5.6	$	3,868
Exercisable at December 31, 2022	686	$	49.31			4.9	$	2,003

Non-vested Restricted Stock Shares Activity

A summary of RSA activity under the Plan during the years ended December 31, 2022, 2021, and 2020 is presented below:

		Weighted
		Average Grant		Weighted Average
(in thousands, except per share and		Date Fair		Remaining Term
remaining term data)	Shares	Value		(years)
Unvested at December 31, 2019	192	$	61.46	2.6
Granted	305		44.42
Vested	(127)		58.88
Forfeited	(18)		51.53
Unvested at December 31, 2020	352	$	48.14	2.7
Granted	541		33.02
Vested	(125)		48.32
Forfeited	(61)		48.16
Unvested at December 31, 2021	707	$	36.52	2.8
Granted	748		32.76
Vested	(245)		36.99
Forfeited	(69)		38.08
Unvested at December 31, 2022	1,141	$	33.86	2.6

2016 Employee Stock Purchase Plan

Summary of allocated expense

(in thousands)	Years Ended December 31,
	2022		2021		2020
Cost of sales	$	50	$	15	$	21
Research and development		41		21		36
Selling, general, and administrative		222		87		123
	$	313	$	123	$	180

2022 Plan

Summary of allocated expense

(in thousands)	Years Ended December 31,
	2022		2021		2020
Cost of sales	$	482	$	5	$	115
Research and development		710		543		561
Selling, general, and administrative		13,094		9,818		12,080
	$	14,286	$	10,366	$	12,756