BUSINESS SEGMENTS AND GEOGRAPHIC INFORMATION - Summary of Financial Information of Reportable Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Revenues	$ 723,956	$ 550,233	$ 2,212,815	$ 1,427,612
Segment operating income (loss)	148,742	33,722	468,170	(31,506)
Intersegment
Segment Reporting Information [Line Items]
Revenues	(17,359)	(14,725)	(51,423)	(41,577)
Segment operating income (loss)	4,470	(2,140)	4,513	(5,453)
Operating Segments
Segment Reporting Information [Line Items]
Revenues	723,956	550,233	2,212,815	1,427,612
Segment operating income (loss)	179,381	56,500	537,332	50,632
North America Solutions
Segment Reporting Information [Line Items]
Revenues	641,612	486,004	1,944,555	1,235,852
North America Solutions | Intersegment
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
North America Solutions | Operating Segments
Segment Reporting Information [Line Items]
Revenues	641,612	486,004	1,944,555	1,235,852
Segment operating income (loss)	169,499	57,353	496,945	29,757
Offshore Gulf of Mexico
Segment Reporting Information [Line Items]
Revenues	31,221	32,701	101,364	91,162
Offshore Gulf of Mexico | Intersegment
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Offshore Gulf of Mexico | Operating Segments
Segment Reporting Information [Line Items]
Revenues	31,221	32,701	101,364	91,162
Segment operating income (loss)	4,705	5,872	18,138	16,616
International Solutions
Segment Reporting Information [Line Items]
Revenues	48,692	29,118	159,383	93,699
International Solutions | Intersegment
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
International Solutions | Operating Segments
Segment Reporting Information [Line Items]
Revenues	48,692	29,118	159,383	93,699
Segment operating income (loss)	(1,397)	(6,550)	4,132	651
Other
Segment Reporting Information [Line Items]
Revenues	2,431	2,410	7,513	6,899
Other | Intersegment
Segment Reporting Information [Line Items]
Revenues	(17,359)	(14,725)	(51,423)	(41,577)
Other | Operating Segments
Segment Reporting Information [Line Items]
Revenues	19,790	17,135	58,936	48,476
Segment operating income (loss)	$ 2,104	$ 1,965	$ 13,604	$ 9,061