Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2023

Equity [Abstract]

Stock-Based Compensation Expense

The following table presents stock-based compensation expense in the Company’s consolidated statements of comprehensive income:

	For the Years Ended December 31,
	2023		2022		2021
	(Amounts in thousands)
Cost of product revenue	$	1,933	$	2,525	$	2,021
Research and development		2,855		2,622		2,856
Selling, general and administrative		20,787		22,169		22,623
Total stock-based compensation	$	25,575	$	27,316	$	27,500

Estimated Weighted Average Assumptions

The fair value of stock option awards granted during the years ended December 31, 2023, 2022 and 2021 were calculated using the following estimated assumptions:

	For the Years Ended December 31,
	2023	2022	2021
Expected term (in years)	5.14-6.5	5.5-6.5	5.5-6.5
Expected volatility (range)	44.78-46.58%	41.44-43.96%	44.57-45.27%
Risk-free interest rate	3.56-4.71%	1.86-4.07%	0.77-1.07%
Expected dividend yield	0%	0%	0%

Summary of Option Activity

Information regarding option activity for the year ended December 31, 2023, under the Plans is summarized below:

	Shares			Weighted average exercise price		Weighted- Average Remaining Contractual Term (in Years)		Aggregate Intrinsic Value (in Thousands)
Options outstanding at December 31, 2022		609,965		$	71.74
Granted		90,305		$	168.22
Exercised		(40,211	)	$	26.76
Forfeited/expired/cancelled		(10,929	)	$	189.46
Options outstanding at December 31, 2023		649,130		$	85.97
Options exercisable at December 31, 2023		364,443		$	65.53
Vested and expected to vest at December 31, 2023(1)		635,834		$	85.49		5.59	$	61,888

(1)Represents the number of vested options as of December 31, 2023 plus the number of unvested options expected to vest as of December 31, 2023, based on the unvested outstanding options at December 31, 2023 adjusted for estimated forfeiture rates of 8% for awards granted to non-executive level employees and 3% for awards granted to executive level employees.

Summary of Restricted Stock Unit Activity

Information regarding stock unit activity, which includes activity for restricted stock units and performance stock units, for the year ended December 31, 2023 under the Plans is summarized below:

	Shares			Weighted Average Grant Date Fair Value
Unvested at December 31, 2022		531,034		$	142.57
Awarded		212,338		$	170.03
Vested		(195,672	)	$	124.58
Forfeited/cancelled		(73,380	)	$	177.81
Unvested at December 31, 2023		474,320		$	155.59
Vested and expected to vest at December 31, 2023(1)		413,249		$	152.74

(1)Represents the number of vested stock units as of December 31, 2023, plus the number of unvested stock units expected to vest as of December 31, 2023, based on the unvested outstanding stock units at December 31, 2023 adjusted for estimated forfeiture rates of 8% for awards granted to non-executive level employees and 3% for awards granted to executive level employees.