SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, RISKS AND UNCERTAINTIES - Narrative (Details)	3 Months Ended			6 Months Ended
	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($) geographical_area	Mar. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 29, 2021 USD ($)	Sep. 27, 2021	Sep. 30, 2020 USD ($)	Dec. 20, 2018 USD ($)	Nov. 13, 2018 USD ($)
Summary of Significant Accounting Policies [Line Items]
Cash, cash equivalents, and short-term investments	$ 350,600,000			$ 350,600,000
Restricted cash	27,200,000		$ 51,400,000	27,200,000	$ 51,400,000	$ 19,200,000			$ 48,900,000
Additional cash restricted at the election of management for potential insurance claims	25,900,000			25,900,000		17,700,000
Increase (decrease) in cash and cash equivalents and restricted cash Label Role				(707,340,000)	(58,112,000)
Payment for extinguishment of long-term debt				487,148,000	0
Adjustments to casualty insurance accruals	1,800,000		2,300,000	(400,000)	2,800,000
Casualty insurance expense	7,900,000		5,000,000	16,700,000	7,500,000
Premium revenues and expenses				26,900,000	15,800,000
Stop-loss program, maximum amount of claim				50,000
Stop-loss medical expenses	3,600,000		3,100,000	$ 6,900,000	5,400,000
Cumulative inflation rate before a country is considered highly inflationary (as a percent)				100.00%
Aggregate foreign currency gain (loss)	$ (2,400,000)		$ (2,400,000)	$ (3,300,000)	$ (4,200,000)
Operating Revenue | Geographic Concentration Risk | International Locations
Summary of Significant Accounting Policies [Line Items]
Concentration percentage	5.90%		5.20%	7.50%	4.90%
Minimum
Summary of Significant Accounting Policies [Line Items]
Number of geographical areas operating in (more than) | geographical_area				1
Argentina
Summary of Significant Accounting Policies [Line Items]
Cash	$ 43,200,000			$ 43,200,000
South America | Operating Revenue | Geographic Concentration Risk | International Locations | International Solutions
Summary of Significant Accounting Policies [Line Items]
Concentration percentage	75.80%		51.40%	76.60%	37.60%
Intercompany Eliminations
Summary of Significant Accounting Policies [Line Items]
Premium revenues and expenses	$ 13,200,000		$ 8,700,000
Acquisition of Drilling Technology Companies
Summary of Significant Accounting Policies [Line Items]
Restricted cash	1,100,000			$ 1,100,000		$ 1,500,000
2018 Credit Facility
Summary of Significant Accounting Policies [Line Items]
Maximum borrowing capacity											$ 750,000,000
Borrowings outstanding	0			0
Available borrowing capacity	$ 750,000,000			$ 750,000,000
2018 Credit Facility | Letters of Credit
Summary of Significant Accounting Policies [Line Items]
Maximum borrowing capacity											$ 75,000,000
Unsecured Senior Notes Issued 2025
Summary of Significant Accounting Policies [Line Items]
Interest rate								4.65%		4.65%
Face amount of debt										$ 487,100,000
Loss on extinguishment of debt		$ 3,700,000
Make-whole premium and accrued interest		$ 56,400,000
Unsecured Senior Notes Issued 2031
Summary of Significant Accounting Policies [Line Items]
Interest rate							2.90%
Face amount of debt							$ 550,000,000