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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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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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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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No definition available.

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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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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	3 Months Ended		6 Months Ended	9 Months Ended
	Jun. 30, 2020 USD ($) rig	Jun. 30, 2019 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 108,400	$ 141,900		$ 366,800	$ 423,700
Abandonments included in depreciation	900	1,400		2,600	6,800
Gain on sale of assets	4,201	$ 9,960		18,790	$ 27,050
Property, plant and equipment, net	3,754,206			3,754,206		$ 4,502,084
Tangible asset impairment charges				83,500
Domestic And International Conventional, FlexRig3, And FlexRig4 Asset Groups
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	605,800			605,800
Tangible asset impairment charges				441,400
In-Process Drilling Equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	68,400			68,400
Tangible asset impairment charges			$ 44,900
Rotational Inventory
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 38,600			38,600
Tangible asset impairment charges			$ 38,600
Domestic Conventional Asset Group
Property, Plant and Equipment [Line Items]
Number of rigs decommissioned \| rig	2
FlexRig3 Asset Group
Property, Plant and Equipment [Line Items]
Number of rigs decommissioned \| rig	35
North America Solutions \| Domestic And International Conventional, FlexRig3, And FlexRig4 Asset Groups
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				292,400
North America Solutions \| In-Process Drilling Equipment
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				75,800
International Solutions \| Domestic And International Conventional, FlexRig3, And FlexRig4 Asset Groups
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				149,000
International Solutions \| Rotational Inventory
Property, Plant and Equipment [Line Items]
Tangible asset impairment charges				$ 7,700