The number of asset groups evaluated for impairment.

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Property, Plant And Equipment, Sale, Number Of Transactions

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Property, Plant And Equipment, Sale, Period For Delivery and Commissioning

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Revenue From Contract With Customer, Percentage

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

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Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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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.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

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PROPERTY, PLANT AND EQUIPMENT - Narrative (Details) $ in Thousands		6 Months Ended	12 Months Ended
	Nov. 15, 2021 USD ($) service transaction	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($) rig service	Sep. 30, 2020 USD ($) industrial_site	Sep. 30, 2019 USD ($)	Mar. 31, 2021 USD ($) rig	Jun. 30, 2019 USD ($) rig	Jun. 29, 2019 USD ($) rig
Property, Plant and Equipment [Line Items]
Net book value			$ 3,127,287	$ 3,646,341
Tangible asset impairment charges				83,500
Asset impairment charges			70,850	563,234	$ 224,327
Depreciation			412,500	474,700	556,900
Abandonments included in depreciation			2,000	4,000	11,400
Assets held-for-sale			71,453	0
Gain (loss) on sale of assets			1,042	$ 46,775	39,691
Number of industrial sites \| industrial_site				6
Total consideration				$ 40,700
Real estate properties				13,500
Gain on sale of investments				27,200
Disposal Group, Held-for-sale, Not Discontinued Operations
Property, Plant and Equipment [Line Items]
Gain (loss) on sale of assets			3,100
United States
Property, Plant and Equipment [Line Items]
Net book value			3,042,140	3,562,525
Domestic And International Conventional, Flex Rig3 And Flex Rig4 Asset Groups
Property, Plant and Equipment [Line Items]
Net book value			605,800
Tangible asset impairment charges				441,400
Domestic And International Conventional, Flex Rig3 And Flex Rig4 Asset Groups \| North America Solutions
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				292,400
Domestic And International Conventional, Flex Rig3 And Flex Rig4 Asset Groups \| International Solutions
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				149,000
In Process Drilling Equipment
Property, Plant and Equipment [Line Items]
Net book value				68,400
Tangible asset impairment charges		$ 44,900
In Process Drilling Equipment \| North America Solutions
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				75,800
Rotational Inventory
Property, Plant and Equipment [Line Items]
Net book value				38,600
Tangible asset impairment charges		$ 38,600
Rotational Inventory \| International Solutions
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				7,700
Domestic Flex Rig4 Asset Group
Property, Plant and Equipment [Line Items]
Net book value							$ 107,500	$ 317,800
Number of drill rigs evaluated for impairment \| rig							20	71
International FlexRig4 Asset Group
Property, Plant and Equipment [Line Items]
Net book value							$ 47,800	$ 55,700
Number of drill rigs evaluated for impairment \| rig							8	10
Domestic Non Super Spec Asset Group \| North America Solutions
Property, Plant and Equipment [Line Items]
Net book value			6,500
Asset impairment charges			56,400
Number of rigs, held-for -sale \| rig						71
Assets held-for-sale						$ 13,500
FlexRig4 Asset Group
Property, Plant and Equipment [Line Items]
Net book value			55,600					$ 235,300
Asset impairment charges			$ 24,000		224,300
Number of rigs, held-for -sale \| rig			8
Assets held-for-sale			$ 29,000
Proceeds from sale of assets			$ 86,500
Period for delivery and commissioning of rigs sold			12 months
FlexRig4 Asset Group \| United Arab Emirates
Property, Plant and Equipment [Line Items]
Number of rigs, held-for -sale \| rig			2
FlexRig4 Asset Group \| United States
Property, Plant and Equipment [Line Items]
Number of rigs, held-for -sale \| rig			6
FlexRig4 Asset Group \| North America Solutions
Property, Plant and Equipment [Line Items]
Asset impairment charges					216,900
FlexRig4 Asset Group \| International Solutions
Property, Plant and Equipment [Line Items]
Asset impairment charges					$ 7,400
Assets Related To Trucking And Casino Running Services \| North America Solutions
Property, Plant and Equipment [Line Items]
Net book value			$ 23,200
Asset impairment charges			14,400
Assets held-for-sale			$ 8,800
Number of services offered \| service			2
Percentage of consolidated revenue			2.80%
Assets Related To Trucking And Casino Running Services \| North America Solutions \| Subsequent Event
Property, Plant and Equipment [Line Items]
Proceeds from sale of assets	$ 5,800
Number of services offered \| service	2
Percentage of consolidated revenue	2.80%
Number of transactions \| transaction	2
Offshore Platform Rig \| Offshore Gulf of Mexico
Property, Plant and Equipment [Line Items]
Net book value			$ 2,800
Proceeds from sale of assets			12,000
Gain (loss) on sale of assets			9,200
Drilling Equipment And Spares
Property, Plant and Equipment [Line Items]
Gain (loss) on sale of assets			(31,200)
Replacement Value Of Damaged Drill Pipe
Property, Plant and Equipment [Line Items]
Gain (loss) on sale of assets			$ 14,400	$ 27,000