UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 356,478	$ (38,586)
Adjustment for (income) loss from discontinued operations	(870)	106
Income (loss) from continuing operations	355,608	(38,480)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	287,721	304,115
Asset impairment charges	12,097	4,363
Amortization of debt discount and debt issuance costs	931	880
Loss on extinguishment of debt	0	60,083
Provision for credit loss	2,165	1,022
Stock-based compensation	23,884	21,214
Gain on investment securities	(6,123)	(55,684)
Gain on reimbursement of drilling equipment	(37,940)	(21,597)
Other gain on sale of assets	(394)	(2,762)
Deferred income tax expense (benefit)	4,197	(36,614)
Other	3,956	(2,765)
Change in assets and liabilities:
Accounts receivable	6,529	(173,625)
Inventories of materials and supplies	(13,899)	(2,482)
Prepaid expenses and other	(27,589)	9,209
Other noncurrent assets	(3,413)	1,829
Accounts payable	24,408	46,775
Accrued liabilities	(15,366)	22,511
Deferred income tax liability	(695)	454
Other noncurrent liabilities	2,980	(21,745)
Net cash provided by operating activities from continuing operations	619,057	116,701
Net cash used in operating activities from discontinued operations	(57)	(60)
Net cash provided by operating activities	619,000	116,641
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(281,790)	(174,958)
Other capital expenditures related to assets held-for-sale	0	(18,228)
Purchase of short-term investments	(102,140)	(109,318)
Purchase of long-term investments	(18,813)	(47,210)
Proceeds from sale of short-term investments	148,651	161,766
Proceeds from sale of long-term investments	0	22,042
Proceeds from asset sales	63,048	50,260
Other	0	(7,500)
Net cash used in investing activities	(191,044)	(123,146)
CASH FLOWS FROM FINANCING ACTIVITIES:
Dividends paid	(152,579)	(80,702)
Payments for employee taxes on net settlement of equity awards	(14,410)	(5,515)
Payment of contingent consideration from acquisition of business	(250)	(250)
Payments for early extinguishment of long-term debt	0	(487,148)
Make-whole premium payment	0	(56,421)
Share repurchases	(247,213)	(76,999)
Other	(540)	(587)
Net cash used in financing activities	(414,992)	(707,622)
Net increase (decrease) in cash and cash equivalents and restricted cash	12,964	(714,127)
Cash and cash equivalents and restricted cash, beginning of period	269,009	936,716
Cash and cash equivalents and restricted cash, end of period	281,973	222,589
Cash paid/(received) during the period:
Interest paid	8,958	10,889
Income tax paid	155,725	3,454
Income tax received	(26,654)	(62)
Payments for operating leases	9,049	9,255
Non-cash operating and investing activities:
Change in accounts payable and accrued liabilities related to purchases of property, plant and equipment	$ 2,031	$ (4,260)