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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended
	Oct. 01, 2023	Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024	Sep. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, share reserve for issuance (in shares)		4,262,537
Granted (in shares)		0	0
Number of options outstanding (in shares)		1,883,128		1,978,516
Stock-based compensation expense		$ 14,175	$ 17,685
Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)		5,063,774		4,913,312
Stock-based compensation expense		$ 14,100	16,200
Weighted average period to recognize pre-tax compensation expense		1 year 6 months
Unrecognized pre-tax compensation expense		$ 75,300
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised		900	600
Stock-based compensation expense		$ 100	1,500
Weighted average period to recognize pre-tax compensation expense		4 days
2013 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserve for issuance (in shares)		2,855,923
Number of shares forfeited (in shares)		161,085
Number of options outstanding (in shares)		1,248,038
2013 Plan \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)		1,607,885
2021 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized (in shares)					8,000,000
Number of shares forfeited (in shares)		277,690
Granted (in shares)		4,176,238
Number of options outstanding (in shares)		32,151
2021 Plan \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)		2,943,382
Inducement Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized (in shares)		832,950
Common stock, share reserve for issuance (in shares)		453,601
Granted (in shares)		428,800
Number of options outstanding (in shares)		602,939
Inducement Awards \| Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based payment award (in shares)		183,750
Visirna ESOP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized (in shares)	20,000,000
Granted (in shares)	7,500,000
Stock-based compensation expense		$ 1,000	$ 2,000