Leases - Components of Operating and Finance Lease Costs (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Leases [Abstract]
Operating lease costs	$ 781	$ 1,278	$ 4,309	$ 8,517	$ 37,637
Variable and short-term lease costs	2,386	1,279	9,545	3,691	5,783
Interest expense on finance lease liabilities	48	1,289	3,530	4,492	547
Amortization expense of finance lease assets	54	4,123	5,163	13,414	2,705
Total lease costs	$ 3,269	$ 7,969	$ 22,547	$ 30,114	$ 46,672

Variable and short-term lease costs.

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 53
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479589/842-20-55-53

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

+ Details

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

+ Details

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Balance Type:	debit
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- References

No definition available.

+ Details

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

+ Details

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