Lessee Operating Lease, Number Of Options To Extend

No definition available.

Name:	hp_LesseeOperatingLeaseNumberOfOptionsToExtend
Namespace Prefix:	hp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980

+ Details

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of operating lease expense. Excludes sublease income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918638-209977

+ Details

Name:	us-gaap_OperatingLeaseExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Present value of lessee's discounted obligation for lease payments from 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 (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_LeaseContractualTermAxis=hp_TulsaCorporateOfficeLeaseMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseContractualTermAxis=hp_TulsaIndustrialFacilityLeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseContractualTermAxis=hp_HoustonAssemblyFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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LEASES - Narrative (Details) $ in Thousands	12 Months Ended
LEASES - Narrative (Details) $ in Thousands	Sep. 30, 2021 USD ($) renewal_option rig	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 17,300	$ 18,600	$ 15,500
Operating lease right-of-use assets	$ 49,187	$ 44,583
Tulsa Corporate Office Lease
Lessee, Lease, Description [Line Items]
Number of renewal options \| renewal_option	2
Renewal option term	5 years
Tulsa Industrial Facility Lease
Lessee, Lease, Description [Line Items]
Number of renewal options \| renewal_option	2
Renewal option term	2 years
Houston Assembly Facility
Lessee, Lease, Description [Line Items]
Number of renewal options \| rig	1
Operating lease right-of-use assets	$ 16,000
Operating Lease, Liability	$ 16,200
Houston Assembly Facility \| Minimum
Lessee, Lease, Description [Line Items]
Renewal option term	5 years
Houston Assembly Facility \| Maximum
Lessee, Lease, Description [Line Items]
Renewal option term	10 years