Represents the number of components in performance units award.

No definition available.

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Namespace Prefix:	hp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the performance cycle of each tranche in a share based payment arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	hp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of tranches in a share based payment arrangement.

+ References

No definition available.

+ Details

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Namespace Prefix:	hp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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

- 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

Gross number of share options (or share units) granted during the period.

+ References

+ Details

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

- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

+ Details

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

- Details

Name:	us-gaap_PlanNameAxis=hp_OmnibusIncentivePlan2016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
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Data Type:	na
Balance Type:
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- Details

Name:	us-gaap_PlanNameAxis=hp_OmnibusIncentivePlan2020Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_PerformanceSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
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- Details

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Data Type:	na
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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STOCK-BASED COMPENSATION - Narrative (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022 USD ($) tranche component $ / shares shares	Sep. 30, 2021 shares	Sep. 30, 2020 shares
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	0	0	0
Stock options outstanding (in shares)	2,400,000
Stock options outstanding (in dollars per share) \| $ / shares	$ 63.90
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period over which awards expire	10 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years		4 years
Unrecognized compensation cost related to unvested awards \| $	$ 24.8
Weighted-average compensation cost recognition period	1 year 8 months 12 days
Restricted Stock \| 2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	743,920
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Unrecognized compensation cost related to unvested awards \| $	$ 8.9
Weighted-average compensation cost recognition period	1 year 9 months 18 days
Number of components included in award units \| component	2
Performance Share Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of units vested	0.00%
Performance Share Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of units vested	200.00%
Performance Share Units \| 2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	227,385
First Component of Performance Share Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance cycle period of each tranche	3 years
Second Component of Performance Share Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period over which awards expire	3 years
Performance cycle period of each tranche	1 year
Number of tranches in component \| tranche	3