Commitments and Contingencies - Warranty Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Mar. 31, 2026	Sep. 30, 2025
Warrant liabilities
Warranty balance, beginning	$ 51,807	$ 40,242
Warranties issued and assumed in period	8,074	22,409
Change in estimates		3,173
Net changes in liability for warranty expirations, costs incurred, and foreign exchange impact	(5,038)	(14,017)
Warranty balance, ending	54,843	51,807
Less: Recoverable warranty costs from suppliers	26,076	23,578
Warranty balance, net of recoverable warranty costs from suppliers, at end of period	$ 28,767	$ 28,229

Standard And Extended Product Warranty Accrual, Net Of Supplier Recoveries

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- Definition

Standard And Extended Product Warranty Accrual, Supplier Recoveries

+ References

No definition available.

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- Definition

Standard Product Warranty Accrual, Change In Estimates

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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- Definition

Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(4)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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