Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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-Publisher FASB
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, RISKS AND UNCERTAINTIES - International Land Drilling Risks (Details) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) greographical_area	Jun. 30, 2018 USD ($)
Unusual Risk or Uncertainty [Line Items]
Cumulative inflation rate before a country is considered highly inflationary (as a percent)			100.00%
Foreign currency gain (loss) \| $	$ 0.1	$ (1.1)	$ (4.6)	$ (2.5)
Minimum
Unusual Risk or Uncertainty [Line Items]
Number of geographical areas operating in (more than) \| greographical_area			1