SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 331,329	$ 360,735	$ 1,049,880	$ 1,086,520
Direct cost and reimbursable expense	275,901	286,619	864,267	884,581
Intercompany expenses	0	0	0	0
Depreciation and amortization	30,615	31,682	92,045	94,119
General and administrative	40,742	43,366	119,682	138,695
Operating expense	347,258	361,667	1,075,994	1,117,395
Loss on impairment	0	0	(117,220)	(1,192)
Gain (loss) on disposal of assets	(16,015)	(4,591)	(18,986)	(12,418)
Earnings from unconsolidated affiliates, net of losses	780	1,996	(2,333)	3,394
Operating loss	(31,164)	(3,527)	(164,653)	(41,091)
Interest expense, net	(27,113)	(19,093)	(80,690)	(53,677)
Other income (expense), net	(3,660)	(736)	(10,814)	235
Loss before benefit (provision) for income taxes	(61,937)	(23,356)	(256,157)	(94,533)
Benefit (provision) for income taxes	(23,764)	13,419	(5,258)	(2,546)
Net loss	(85,701)	(9,937)	(261,415)	(97,079)
Net (income) loss attributable to noncontrolling interests	(243)	1,664	(827)	2,322
Net loss attributable to Bristow Group	(85,944)	(8,273)	(262,242)	(94,757)
External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	331,329	360,735	1,049,880	1,086,520
Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Eliminations
Condensed Financial Statements, Captions [Line Items]
Revenue	(26,844)	(28,608)	(80,857)	(92,518)
Direct cost and reimbursable expense	0	0	0	0
Intercompany expenses	(26,844)	(28,608)	(80,857)	(92,518)
Depreciation and amortization	0	0	0	0
General and administrative	0	0	0	0
Operating expense	(26,844)	(28,608)	(80,857)	(92,518)
Loss on impairment			0	0
Gain (loss) on disposal of assets	0	0	0	0
Earnings from unconsolidated affiliates, net of losses	22,023	11,503	153,319	22,506
Operating loss	22,023	11,503	153,319	22,506
Interest expense, net	0	0	0	0
Other income (expense), net	0	0	0	0
Loss before benefit (provision) for income taxes	22,023	11,503	153,319	22,506
Benefit (provision) for income taxes	0	0	0	0
Net loss	22,023	11,503	153,319	22,506
Net (income) loss attributable to noncontrolling interests	0	0	0	0
Net loss attributable to Bristow Group	22,023	11,503	153,319	22,506
Eliminations | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Eliminations | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	(26,844)	(28,608)	(80,857)	(92,518)
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Revenue	(9)	188	81	188
Direct cost and reimbursable expense	14	81	50	3,350
Intercompany expenses	5,399	0	20,706	0
Depreciation and amortization	3,087	3,048	9,245	8,981
General and administrative	16,004	13,937	41,699	50,924
Operating expense	24,504	17,066	71,700	63,255
Loss on impairment			0	0
Gain (loss) on disposal of assets	(512)	(1,757)	(1,318)	(1,757)
Earnings from unconsolidated affiliates, net of losses	(22,023)	(11,503)	(153,319)	(22,506)
Operating loss	(47,048)	(30,138)	(226,256)	(87,330)
Interest expense, net	(16,997)	(9,480)	(48,940)	(29,174)
Other income (expense), net	122	(16)	306	(142)
Loss before benefit (provision) for income taxes	(63,923)	(39,634)	(274,890)	(116,646)
Benefit (provision) for income taxes	(22,006)	31,373	12,691	21,925
Net loss	(85,929)	(8,261)	(262,199)	(94,721)
Net (income) loss attributable to noncontrolling interests	(15)	(12)	(43)	(36)
Net loss attributable to Bristow Group	(85,944)	(8,273)	(262,242)	(94,757)
Parent Company Only | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	(9)	188	81	188
Parent Company Only | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenue	64,097	75,985	189,043	232,622
Direct cost and reimbursable expense	40,188	49,540	123,045	147,829
Intercompany expenses	0	0	0	0
Depreciation and amortization	19,175	12,489	55,130	38,209
General and administrative	4,174	6,514	13,097	17,899
Operating expense	63,537	68,543	191,272	203,937
Loss on impairment			(87,474)	(1,192)
Gain (loss) on disposal of assets	(15,321)	(3,657)	(16,799)	7,356
Earnings from unconsolidated affiliates, net of losses	0	0	0	0
Operating loss	(14,761)	3,785	(106,502)	34,849
Interest expense, net	(5,807)	(5,008)	(18,552)	(16,811)
Other income (expense), net	485	227	1,802	(529)
Loss before benefit (provision) for income taxes	(20,083)	(996)	(123,252)	17,509
Benefit (provision) for income taxes	(463)	(1,791)	(746)	(7,896)
Net loss	(20,546)	(2,787)	(123,998)	9,613
Net (income) loss attributable to noncontrolling interests	0	0	0	0
Net loss attributable to Bristow Group	(20,546)	(2,787)	(123,998)	9,613
Guarantor Subsidiaries | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	37,253	47,377	108,186	140,104
Guarantor Subsidiaries | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	26,844	28,608	80,857	92,518
Non- Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenue	294,085	313,170	941,613	946,228
Direct cost and reimbursable expense	235,699	236,998	741,172	733,402
Intercompany expenses	21,445	28,608	60,151	92,518
Depreciation and amortization	8,353	16,145	27,670	46,929
General and administrative	20,564	22,915	64,886	69,872
Operating expense	286,061	304,666	893,879	942,721
Loss on impairment			(29,746)	0
Gain (loss) on disposal of assets	(182)	823	(869)	(18,017)
Earnings from unconsolidated affiliates, net of losses	780	1,996	(2,333)	3,394
Operating loss	8,622	11,323	14,786	(11,116)
Interest expense, net	(4,309)	(4,605)	(13,198)	(7,692)
Other income (expense), net	(4,267)	(947)	(12,922)	906
Loss before benefit (provision) for income taxes	46	5,771	(11,334)	(17,902)
Benefit (provision) for income taxes	(1,295)	(16,163)	(17,203)	(16,575)
Net loss	(1,249)	(10,392)	(28,537)	(34,477)
Net (income) loss attributable to noncontrolling interests	(228)	1,676	(784)	2,358
Net loss attributable to Bristow Group	(1,477)	(8,716)	(29,321)	(32,119)
Non- Guarantor Subsidiaries | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	294,085	313,170	941,613	946,228
Non- Guarantor Subsidiaries | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 0	$ 0	$ 0	$ 0