Commitments and Contingencies (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Sep. 30, 2022
Operating Leased Assets [Line Items]
Net prepaid expenses from excess of credits earned over credits used	$ 2,300	$ 4,000
Accrued tool sets	4,316	3,176
Liability to vendor for vouchers redeemed by students	400	2,300
Concorde
Operating Leased Assets [Line Items]
Amount contributed to surety bond	4,600
Surety Bond
Operating Leased Assets [Line Items]
Maximum principal amount	$ 21,900	$ 20,500

Face (par) amount of debt instrument at time of issuance.

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