Stock-based compensation (Tables)

6 Months Ended

Mar. 31, 2022

Share-based Payment Arrangement [Abstract]

Schedule of Activity Under the Equity Incentive Plans

Activity under the equity incentive plans during the six months ended March 31, 2022 is summarized below:

(In thousands, except per share data)	Shares available	Options outstanding	Weighted average exercise price per share		Weighted average remaining contractual term (years)	Aggregate intrinsic value
Outstanding at September 30, 2021	1,728	3,132	$	27.15	7.3	$	251,343
Additional shares authorized	1,000
Stock options granted	(214)	214	26.14		—	—
Stock options exercised	—	(368)	13.05		—	—
Stock options forfeited	89	(89)	31.96		—	—
Restricted stock units granted	(1,150)	—	—		—	—
Forfeiture of restricted stock units	67	—	—		—	—
Shares withheld for payment of taxes	62	—	—		—	—
Outstanding at March 31, 2022	1,582	2,889	$	28.79	7.0	$	70,722
Vested or expected to vest at March 31, 2022	—	2,889	$	28.79	7.0	$	70,722
Vested and exercisable at March 31, 2022	—	1,739	$	21.00	6.4	$	51,266

Schedule of Stock-Based Compensation Expenses

Total stock-based compensation expense recognized was as follows:

	Three months ended March 31,				Six months ended March 31,
(in thousands)	2022		2021		2022		2021
Cost of revenues	$	1,241	$	731	$	2,119	$	1,218
Research and development	4,838		2,427		8,865		4,428
Selling, general and administrative	16,258		8,394		29,421		12,929
Total stock-based compensation	$	22,337	$	11,552	$	40,405	$	18,575

Schedule of Nonvested Performance Stock Units Activity

Activity under the PSUs during the six months ended March 31, 2022 is summarized below:

(in thousands, except per share data)	Number of shares	Weighted average grant date fair value		Weighted average remaining contractual term	Aggregate intrinsic value
Outstanding at September 30, 2021	10	$	3.59	2.3	$	1,016
Performance stock units granted	342	80.31		—	—
Performance stock units forfeited	(1)	3.34		—	—
Outstanding at March 31, 2022	351	$	81.21	2.1	$	17,328
Vested or expected to vest and exercisable at March 31, 2022	351	$	81.21	2.1	$	17,328

Schedule of Nonvested Restricted Stock Units Activity

Activity with respect to the Company’s restricted stock units during the six months ended March 31, 2022 was as follows:

(in thousands, except per share data)	Number of Shares	Weighted average grant date fair value per share		Weighted average remaining contractual term (years)	Aggregate Intrinsic Value
Outstanding at September 30, 2021	698	$	73.27	2.7	$	74,613
Restricted stock units granted	807	79.26		—	—
Restricted stock units vested	(164)	72.93		—	—
Restricted stock units forfeited	(66)	73.95		—	—
Outstanding at March 31, 2022	1,275	$	85.41	3.2	$	62,971
Expected to vest at March 31, 2022	1,275	$	85.41	3.2	$	62,971

Summary of Stock Option Valuation Assumptions

The number of shares reserved for issuance as at March 31, 2022 is as follows:

(In thousands)	Shares available
Outstanding at September 30, 2021	355
Additional shares authorized	249
Shares issued during the period	(50)
Outstanding at March 31, 2022	554