Stock-based Compensation (Tables)

6 Months Ended

Mar. 31, 2025

Share-Based Payment Arrangement [Abstract]

Schedule of Stock-Based Compensation Expenses

The Company recorded stock-based compensation expense in the condensed consolidated statement of operations and comprehensive loss for the periods presented as follows (in thousands):

	Three Months Ended March 31,				Six Months Ended March 31,
(in thousands)	2025		2024		2025		2024
Cost of revenues	$	2,074	$	1,049	$	3,280	$	1,973
Research and development	3,527		3,376		6,266		6,214
Selling, general and administrative	14,727		9,399		22,773		16,657
Total stock-based compensation expense	$	20,328	$	13,824	$	32,319	$	24,844

Schedule of Nonvested Restricted Stock Units Activity

A summary of the Company’s restricted stock unit activity excluding the performance-based restricted stock units during the six months ended March 31, 2025 was as follows:

(in thousands, except per share data)	Shares	Weighted average grant date fair value per share
Nonvested shares at September 30, 2024	1,964	$	32.13
Granted	1,120	47.36
Vested/Issued	(499)	39.03
Forfeited	(170)	33.25
Nonvested shares at March 31, 2025	2,415	$	37.68

Schedule of Nonvested Performance-based Units Activity

A summary of the Company’s performance-based restricted stock units activity during the six months ended March 31, 2025 was as follows:

(in thousands, except per share data)	Shares	Weighted average grant date fair value per share
Nonvested shares at September 30, 2024	1,167	$	27.01
Granted	1,354	47.75
Vested/Issued	(311)	44.89
Forfeited	(111)	25.27
Nonvested shares at March 31, 2025	2,099	$	37.83

Schedule of Activity Under Option and Performance Stock Options

A summary of the Company’s stock options including the performance-based stock options during the six months ended March 31, 2025 was as follows:

(in thousands, except per share data)	Shares	Weighted average exercise price per share		Weighted average remaining contractual term (years)	Aggregate intrinsic value
Outstanding at September 30, 2024	1,892	$	29.60	4.57	$	37,840
Forfeited	(61)	67.88		—	—
Exercised	(238)	15.64		—	7,154
Outstanding at March 31, 2025	1,593	$30.23		4.19	$	22,643
Vested and exercisable at March 31, 2025	1,562	$	30.14	4.13	$	22,404

Summary of Stock Option Valuation Assumptions

The number of shares of the Company's common stock reserved for issuance under the 2018 Employee Stock Purchase Plan ("ESPP") at March 31, 2025 was as follows:

(In thousands)	Shares available
Outstanding at September 30, 2024	611
Additional shares authorized	249
Shares issued during the period	(65)
Outstanding at March 31, 2025	795