SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION - Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ (198,083)	$ (176,890)	$ (77,149)
Currency translation adjustments	25,927	(21,636)	(21,604)
Pension liability adjustment	12,333	(11,511)	705
Unrealized loss on cash flow hedges, net of tax benefit	(346)	0	0
Total comprehensive loss	(160,169)	(210,037)	(98,048)
Net loss attributable to noncontrolling interests	2,425	6,354	4,707
Currency translation adjustments attributable to noncontrolling interests	4,269	(5,311)	1,409
Total comprehensive loss attributable to noncontrolling interests	6,694	1,043	6,116
Total comprehensive loss attributable to Bristow Group	153,475	208,994	91,932
Accretion of redeemable noncontrolling interests	0	0	(1,498)
Total comprehensive loss attributable to common stockholders	(153,475)	(208,994)	(93,430)
Eliminations
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	104,396	28,161	(1,230)
Currency translation adjustments	(66,802)	(231,089)	165,206
Pension liability adjustment	0	0	0
Unrealized loss on cash flow hedges, net of tax benefit	0
Total comprehensive loss	37,594	(202,928)	163,976
Net loss attributable to noncontrolling interests	0	0	0
Currency translation adjustments attributable to noncontrolling interests	0	0	0
Total comprehensive loss attributable to noncontrolling interests	0	0	0
Total comprehensive loss attributable to Bristow Group	(37,594)	202,928	(163,976)
Accretion of redeemable noncontrolling interests			0
Total comprehensive loss attributable to common stockholders			163,976
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(195,607)	(170,486)	(72,385)
Currency translation adjustments	0	0	2
Pension liability adjustment	0	0	0
Unrealized loss on cash flow hedges, net of tax benefit	0
Total comprehensive loss	(195,607)	(170,486)	(72,383)
Net loss attributable to noncontrolling interests	(51)	(50)	(57)
Currency translation adjustments attributable to noncontrolling interests	0	0	0
Total comprehensive loss attributable to noncontrolling interests	(51)	(50)	(57)
Total comprehensive loss attributable to Bristow Group	195,658	170,536	72,440
Accretion of redeemable noncontrolling interests			0
Total comprehensive loss attributable to common stockholders			(72,440)
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	16,663	(24,107)	1,171
Currency translation adjustments	992	388	0
Pension liability adjustment	0	0	0
Unrealized loss on cash flow hedges, net of tax benefit	0
Total comprehensive loss	17,655	(23,719)	1,171
Net loss attributable to noncontrolling interests	0	0	0
Currency translation adjustments attributable to noncontrolling interests	0	0	0
Total comprehensive loss attributable to noncontrolling interests	0	0	0
Total comprehensive loss attributable to Bristow Group	(17,655)	23,719	(1,171)
Accretion of redeemable noncontrolling interests			0
Total comprehensive loss attributable to common stockholders			1,171
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(123,535)	(10,458)	(4,705)
Currency translation adjustments	91,737	209,065	(186,812)
Pension liability adjustment	12,333	(11,511)	705
Unrealized loss on cash flow hedges, net of tax benefit	(346)
Total comprehensive loss	(19,811)	187,096	(190,812)
Net loss attributable to noncontrolling interests	2,476	6,404	4,764
Currency translation adjustments attributable to noncontrolling interests	4,269	(5,311)	1,409
Total comprehensive loss attributable to noncontrolling interests	6,745	1,093	6,173
Total comprehensive loss attributable to Bristow Group	$ 13,066	$ (188,189)	184,639
Accretion of redeemable noncontrolling interests			(1,498)
Total comprehensive loss attributable to common stockholders			$ (186,137)