Leases - Maturities of lease liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2021	Sep. 30, 2020
Leases [Abstract]
2022		$ 43,164
2023		38,690
2024		32,106
2025		23,927
2026		18,278
Thereafter		144,718
Total lease payments		300,883
Less: Imputed interest		49,711
Total		251,172	$ 245,418
Short-term lease liabilities		38,140
Total lease liabilities		213,032
Finance Leases
2022		1,342
2023		1,365
2024		1,388
2025		1,411
2026		1,435
Thereafter		22,868
Total lease payments		29,809
Less: Imputed interest		11,070
Total		18,739	8,631
Short-term lease liabilities		452	165
Long-term lease liabilities		18,287	8,466
Operating Leases
2022		41,822
2023		37,325
2024		30,718
2025		22,516
2026		16,843
Thereafter		121,850
Total lease payments		271,074
Less: Imputed interest		38,641
Total		232,433
Short-term lease liabilities		37,688	35,716
Long-term lease liabilities		$ 194,745	$ 201,071
Lease and rental expense	$ 40,400

Lease Liability

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- Definition

Lease Liability, Current

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No definition available.

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- Definition

Lease Liability, Imputed Interest

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Lease Liability, Lease Payments

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- Definition

Lease Liability, Noncurrent

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Lessee, Liability, Payments, Due After Rolling Five Years

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No definition available.

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No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980

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-Publisher FASB
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-Section 45
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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-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 finance lease, classified as noncurrent.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease due in next rolling 12 months following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due after fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fifth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in fourth rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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

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

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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