BUSINESS SEGMENTS AND GEOGRAPHIC INFORMATION - Reconciliation of Segment Assets to Consolidated Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Segment Reporting Information [Line Items]
Assets	$ 4,365,733	$ 4,355,531
Operating Segments
Segment Reporting Information [Line Items]
Assets	4,079,090	3,939,096
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Assets	286,643	416,435
North America Solutions | Operating Segments
Segment Reporting Information [Line Items]
Assets	3,445,085	3,406,824
Offshore Gulf of Mexico | Operating Segments
Segment Reporting Information [Line Items]
Assets	82,935	80,993
International Solutions | Operating Segments
Segment Reporting Information [Line Items]
Assets	401,629	330,974
Other | Operating Segments
Segment Reporting Information [Line Items]
Assets	$ 149,441	$ 120,305