SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 360,735	$ 337,443	$ 1,086,520	$ 1,064,308
Direct cost and reimbursable expense	286,589	272,549	884,493	869,612
Intercompany expenses	0	0	0	0
Depreciation and amortization	31,682	29,768	94,119	93,054
General and administrative	43,366	45,409	138,695	149,278
Operating expense	361,637	347,726	1,117,307	1,111,944
Loss on impairment	0	(8,706)	(1,192)	(16,278)
Gain (loss) on disposal of assets	(4,591)	(874)	(12,418)	(13,077)
Earnings from unconsolidated affiliates, net of losses	1,996	766	3,394	4,777
Operating loss	(3,497)	(19,097)	(41,003)	(72,214)
Interest expense, net	(19,093)	(12,179)	(53,677)	(34,533)
Other income (expense), net	(766)	1,668	147	(1,518)
Income (loss) before (provision) benefit for income taxes	(23,356)	(29,608)	(94,533)	(108,265)
Benefit (provision) for income taxes	13,419	3,560	(2,546)	11,038
Net loss	(9,937)	(26,048)	(97,079)	(97,227)
Net (income) loss attributable to noncontrolling interests	1,664	4,121	2,322	4,731
Net loss attributable to Bristow Group	(8,273)	(21,927)	(94,757)	(92,496)
External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	360,735	337,443	1,086,520	1,064,308
Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Eliminations
Condensed Financial Statements, Captions [Line Items]
Revenue	(28,608)	(29,799)	(92,518)	(78,413)
Direct cost and reimbursable expense	0	0	0	0
Intercompany expenses	(28,608)	(29,799)	(92,518)	(78,413)
Depreciation and amortization	0	0	0	0
General and administrative	0	0	0	0
Operating expense	(28,608)	(29,799)	(92,518)	(78,413)
Loss on impairment		0	0	0
Gain (loss) on disposal of assets	0	0	0	0
Earnings from unconsolidated affiliates, net of losses	11,503	(4,561)	22,506	17,905
Operating loss	11,503	(4,561)	22,506	17,905
Interest expense, net	0	0	0	0
Other income (expense), net	0	0	0	0
Income (loss) before (provision) benefit for income taxes	11,503	(4,561)	22,506	17,905
Benefit (provision) for income taxes	0	0	0	0
Net loss	11,503	(4,561)	22,506	17,905
Net (income) loss attributable to noncontrolling interests	0	0	0	0
Net loss attributable to Bristow Group	11,503	(4,561)	22,506	17,905
Eliminations | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	0	0	0	0
Eliminations | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	(28,608)	(29,799)	(92,518)	(78,413)
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Revenue	188	0	188	0
Direct cost and reimbursable expense	81	703	3,350	72
Intercompany expenses	0	0	0	0
Depreciation and amortization	3,048	2,233	8,981	6,549
General and administrative	13,937	13,897	50,924	51,643
Operating expense	17,066	16,833	63,255	58,264
Loss on impairment		0	0	0
Gain (loss) on disposal of assets	(1,757)	0	(1,757)	0
Earnings from unconsolidated affiliates, net of losses	(11,503)	4,562	(22,506)	(17,861)
Operating loss	(30,138)	(12,271)	(87,330)	(76,125)
Interest expense, net	(9,480)	(11,525)	(29,174)	(31,757)
Other income (expense), net	(16)	497	(142)	1,249
Income (loss) before (provision) benefit for income taxes	(39,634)	(23,299)	(116,646)	(106,633)
Benefit (provision) for income taxes	31,373	1,386	21,925	14,178
Net loss	(8,261)	(21,913)	(94,721)	(92,455)
Net (income) loss attributable to noncontrolling interests	(12)	(13)	(36)	(40)
Net loss attributable to Bristow Group	(8,273)	(21,926)	(94,757)	(92,495)
Parent Company Only | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	188	0	188	0
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	75,985	69,357	232,622	205,827
Direct cost and reimbursable expense	49,540	45,794	147,829	142,270
Intercompany expenses	0	0	0	0
Depreciation and amortization	12,489	10,942	38,209	38,728
General and administrative	6,514	5,841	17,899	18,921
Operating expense	68,543	62,577	203,937	199,919
Loss on impairment		0	(1,192)	(4,761)
Gain (loss) on disposal of assets	(3,657)	(361)	7,356	(11,936)
Earnings from unconsolidated affiliates, net of losses	0	0	0	0
Operating loss	3,785	6,419	34,849	(10,789)
Interest expense, net	(5,008)	(42)	(16,811)	(1,070)
Other income (expense), net	227	1,666	(529)	3,312
Income (loss) before (provision) benefit for income taxes	(996)	8,043	17,509	(8,547)
Benefit (provision) for income taxes	(1,791)	(1,138)	(7,896)	(4,870)
Net loss	(2,787)	6,905	9,613	(13,417)
Net (income) loss attributable to noncontrolling interests	0	0	0	0
Net loss attributable to Bristow Group	(2,787)	6,905	9,613	(13,417)
Guarantor Subsidiaries | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	47,377	39,558	140,104	127,414
Guarantor Subsidiaries | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	28,608	29,799	92,518	78,413
Non- Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Revenue	313,170	297,885	946,228	936,894
Direct cost and reimbursable expense	236,968	226,052	733,314	727,270
Intercompany expenses	28,608	29,799	92,518	78,413
Depreciation and amortization	16,145	16,593	46,929	47,777
General and administrative	22,915	25,671	69,872	78,714
Operating expense	304,636	298,115	942,633	932,174
Loss on impairment		(8,706)	0	(11,517)
Gain (loss) on disposal of assets	823	(513)	(18,017)	(1,141)
Earnings from unconsolidated affiliates, net of losses	1,996	765	3,394	4,733
Operating loss	11,353	(8,684)	(11,028)	(3,205)
Interest expense, net	(4,605)	(612)	(7,692)	(1,706)
Other income (expense), net	(977)	(495)	818	(6,079)
Income (loss) before (provision) benefit for income taxes	5,771	(9,791)	(17,902)	(10,990)
Benefit (provision) for income taxes	(16,163)	3,312	(16,575)	1,730
Net loss	(10,392)	(6,479)	(34,477)	(9,260)
Net (income) loss attributable to noncontrolling interests	1,676	4,134	2,358	4,771
Net loss attributable to Bristow Group	(8,716)	(2,345)	(32,119)	(4,489)
Non- Guarantor Subsidiaries | External Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	313,170	297,885	946,228	936,894
Non- Guarantor Subsidiaries | Intercompany Customer
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 0	$ 0	$ 0	$ 0