Commitments and contingencies - Operating Leases On Balance Sheet (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Assets:
Operating lease right-of-use assets	$ 78,215	$ 61,580
Current liabilities:
Current portion of operating lease liability	14,166	8,213
Noncurrent liabilities:
Operating lease liability, net of current portion	$ 65,496	$ 53,156

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

+ References

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Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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