GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Operating revenues	$ 687,974	$ 648,872	$ 2,149,440	$ 1,790,443
Operating costs and other	855,848	642,566	2,167,879	1,781,692
Operating income (loss) from continuing operations	(167,874)	6,306	(18,439)	8,751
Other income (expense), net	(12,521)	2,048	(44,418)	5,850
Interest expense	(6,257)	(5,993)	(17,145)	(17,794)
Equity in net loss of subsidiaries	0	0	0	0
Income (loss) from continuing operations before income taxes	(186,652)	2,361	(80,002)	(3,193)
Income tax (benefit) provision	(32,031)	10,535	(5,602)	(494,028)
Income (loss) from continuing operations	(154,621)	(8,174)	(74,400)	490,835
Income from discontinued operations before income taxes	7,244	8,383	22,798	9,127
Income tax provision	7,306	8,217	23,231	19,743
Income (loss) from discontinued operations	(62)	166	(433)	(10,616)
Net income (loss)	(154,683)	(8,008)	(74,833)	480,219
Eliminations
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Operating revenues	(4,180)	(27)	(4,228)	(64)
Operating costs and other	(4,357)	(218)	(4,896)	(669)
Operating income (loss) from continuing operations	177	191	668	605
Other income (expense), net	(177)	(191)	(668)	(605)
Interest expense	0	0	0	0
Equity in net loss of subsidiaries	148,857	6,976	49,077	(497,765)
Income (loss) from continuing operations before income taxes	148,857	6,976	49,077	(497,765)
Income tax (benefit) provision	0	0	0	0
Income (loss) from continuing operations	148,857	6,976	49,077	(497,765)
Income from discontinued operations before income taxes	0	0	0	0
Income tax provision	0	0	0	0
Income (loss) from discontinued operations	0	0	0	0
Net income (loss)	148,857	6,976	49,077	(497,765)
Helmerich & Payne, Inc. (Guarantor) | Reportable Legal Entities
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Operating revenues	0	0	0	0
Operating costs and other	2,942	4,151	8,526	12,360
Operating income (loss) from continuing operations	(2,942)	(4,151)	(8,526)	(12,360)
Other income (expense), net	(35)	107	(77)	210
Interest expense	(6,083)	(108)	(13,202)	(274)
Equity in net loss of subsidiaries	(145,440)	(4,883)	(55,331)	494,574
Income (loss) from continuing operations before income taxes	(154,500)	(9,035)	(77,136)	482,150
Income tax (benefit) provision	183	(1,027)	(2,303)	1,931
Income (loss) from continuing operations	(154,683)	(8,008)	(74,833)	480,219
Income from discontinued operations before income taxes	0	0	0	0
Income tax provision	0	0	0	0
Income (loss) from discontinued operations	0	0	0	0
Net income (loss)	(154,683)	(8,008)	(74,833)	480,219
Helmerich & Payne International Drilling Co. (Issuer) | Reportable Legal Entities
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Operating revenues	633,284	574,252	1,951,221	1,584,970
Operating costs and other	780,880	557,994	1,937,425	1,542,815
Operating income (loss) from continuing operations	(147,596)	16,258	13,796	42,155
Other income (expense), net	(12,639)	1,854	(45,275)	5,226
Interest expense	(132)	(5,117)	(4,844)	(15,368)
Equity in net loss of subsidiaries	(3,417)	(2,093)	6,254	3,191
Income (loss) from continuing operations before income taxes	(163,784)	10,902	(30,069)	35,204
Income tax (benefit) provision	(43,271)	17,384	(11,884)	(459,571)
Income (loss) from continuing operations	(120,513)	(6,482)	(18,185)	494,775
Income from discontinued operations before income taxes	0	0	0	0
Income tax provision	0	0	0	0
Income (loss) from discontinued operations	0	0	0	0
Net income (loss)	(120,513)	(6,482)	(18,185)	494,775
Non-Guarantor Subsidiaries | Reportable Legal Entities
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Operating revenues	58,870	74,647	202,447	205,537
Operating costs and other	76,383	80,639	226,824	227,186
Operating income (loss) from continuing operations	(17,513)	(5,992)	(24,377)	(21,649)
Other income (expense), net	330	278	1,602	1,019
Interest expense	(42)	(768)	901	(2,152)
Equity in net loss of subsidiaries	0	0	0	0
Income (loss) from continuing operations before income taxes	(17,225)	(6,482)	(21,874)	(22,782)
Income tax (benefit) provision	11,057	(5,822)	8,585	(36,388)
Income (loss) from continuing operations	(28,282)	(660)	(30,459)	13,606
Income from discontinued operations before income taxes	7,244	8,383	22,798	9,127
Income tax provision	7,306	8,217	23,231	19,743
Income (loss) from discontinued operations	(62)	166	(433)	(10,616)
Net income (loss)	$ (28,344)	$ (494)	$ (30,892)	$ 2,990