SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION BS (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$ 120,394	$ 104,146	$ 133,804	$ 204,341
Accounts Receivable, Net, Current	258,277	258,618
Inventories	151,947	147,169
Assets held for sale	38,636	57,827
Prepaid expenses and other current assets	60,640	70,091
Total current assets	629,894	637,851
Intercompany investment	0	0
Investment in unconsolidated affiliates	223,233	216,376
Intercompany notes receivable	0	0
Total property and equipment, at cost	2,653,032	2,665,828
Less - Accumulated depreciation and amortization	(506,860)	(508,727)
Property, Plant and Equipment, Net	2,146,172	2,157,101
Goodwill	77,998	75,628
Other assets	165,394	143,764
Total assets	3,242,691	3,230,720
Accounts payable	98,253	84,193
Accrued liabilities	243,491	258,445
Current deferred taxes	4,133	17,704
Short-term borrowings and current maturities of long-term debt	26,954	18,730
Deferred sale leaseback advance	0	55,934
Total current liabilities	372,831	435,006
Long-term debt, less current maturities	918,247	845,692
Intercompany notes payable	0	0
Accrued pension liabilities	101,911	99,576
Other liabilities and deferred credits	31,224	39,782
Deferred taxes	169,380	165,655
Redeemable noncontrolling interests	35,342	26,223
Common stock	376	376
Additional paid-in capital	782,620	781,837
Retained earnings	1,263,013	1,284,442
Accumulated other comprehensive income (loss)	(255,615)	(270,329)
Treasury shares, at cost	(184,796)	(184,796)
Total Bristow Group stockholders' equity	1,605,598	1,611,530
Noncontrolling interests	8,158	7,256
Total stockholders' investment	1,613,756	1,618,786
Total liabilities, redeemable noncontrolling interests and stockholders’ investment	3,242,691	3,230,720
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	8,467	126	6,660	4,640
Accounts Receivable, Net, Current	420,427	377,158
Inventories	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	4,043	4,850
Total current assets	432,937	382,134
Intercompany investment	1,366,976	1,410,347
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	1,227,432	1,184,335
Total property and equipment, at cost	122,211	111,287
Less - Accumulated depreciation and amortization	(18,037)	(16,431)
Property, Plant and Equipment, Net	104,174	94,856
Goodwill	0	0
Other assets	167,011	43,423
Total assets	3,298,530	3,115,095
Accounts payable	302,985	203,700
Accrued liabilities	16,116	31,805
Current deferred taxes	2,572	(3,661)
Short-term borrowings and current maturities of long-term debt	17,501	9,088
Deferred sale leaseback advance	0	0
Total current liabilities	339,174	240,932
Long-term debt, less current maturities	886,988	812,536
Intercompany notes payable	100,000	100,000
Accrued pension liabilities	0	0
Other liabilities and deferred credits	10,132	17,144
Deferred taxes	143,708	141,771
Redeemable noncontrolling interests	0	0
Common stock	376	376
Additional paid-in capital	782,620	781,837
Retained earnings	1,263,013	1,284,442
Accumulated other comprehensive income (loss)	(44,233)	(80,604)
Treasury shares, at cost	(184,796)	(184,796)
Total Bristow Group stockholders' equity	1,816,980	1,801,255
Noncontrolling interests	1,548	1,457
Total stockholders' investment	1,818,528	1,802,712
Total liabilities, redeemable noncontrolling interests and stockholders’ investment	3,298,530	3,115,095
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	0	884	0	0
Accounts Receivable, Net, Current	444,319	342,239
Inventories	40,119	44,285
Assets held for sale	36,362	54,695
Prepaid expenses and other current assets	6,140	7,035
Total current assets	526,940	449,138
Intercompany investment	111,379	111,380
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	13,786	0
Total property and equipment, at cost	1,093,606	1,165,164
Less - Accumulated depreciation and amortization	(216,145)	(223,245)
Property, Plant and Equipment, Net	877,461	941,919
Goodwill	4,756	4,756
Other assets	1,001	988
Total assets	1,535,323	1,508,181
Accounts payable	460,061	369,854
Accrued liabilities	39,276	37,860
Current deferred taxes	1,917	2,503
Short-term borrowings and current maturities of long-term debt	0	0
Deferred sale leaseback advance	0	55,934
Total current liabilities	501,254	466,151
Long-term debt, less current maturities	0	0
Intercompany notes payable	122,897	131,075
Accrued pension liabilities	0	0
Other liabilities and deferred credits	7,670	8,379
Deferred taxes	6,140	6,346
Redeemable noncontrolling interests	0	0
Common stock	4,996	4,996
Additional paid-in capital	9,291	9,291
Retained earnings	883,075	881,943
Accumulated other comprehensive income (loss)	0	0
Treasury shares, at cost	0	0
Total Bristow Group stockholders' equity	897,362	896,230
Noncontrolling interests	0	0
Total stockholders' investment	897,362	896,230
Total liabilities, redeemable noncontrolling interests and stockholders’ investment	1,535,323	1,508,181
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	112,059	103,136	129,008	200,147
Accounts Receivable, Net, Current	472,889	447,776
Inventories	111,828	102,884
Assets held for sale	2,274	3,132
Prepaid expenses and other current assets	50,457	58,206
Total current assets	749,507	715,134
Intercompany investment	158,843	0
Investment in unconsolidated affiliates	223,233	216,376
Intercompany notes receivable	0	0
Total property and equipment, at cost	1,437,215	1,389,377
Less - Accumulated depreciation and amortization	(272,678)	(269,051)
Property, Plant and Equipment, Net	1,164,537	1,120,326
Goodwill	73,242	70,872
Other assets	106,390	99,353
Total assets	2,475,752	2,222,061
Accounts payable	329,636	289,838
Accrued liabilities	1,248,960	206,789
Current deferred taxes	(356)	18,862
Short-term borrowings and current maturities of long-term debt	9,453	9,642
Deferred sale leaseback advance	0	0
Total current liabilities	1,587,693	525,131
Long-term debt, less current maturities	31,259	33,156
Intercompany notes payable	152,849	1,065,918
Accrued pension liabilities	101,911	99,576
Other liabilities and deferred credits	221,175	21,711
Deferred taxes	19,532	17,538
Redeemable noncontrolling interests	35,342	26,223
Common stock	22,876	22,876
Additional paid-in capital	284,048	284,048
Retained earnings	110,692	133,559
Accumulated other comprehensive income (loss)	(98,235)	(13,474)
Treasury shares, at cost	0	0
Total Bristow Group stockholders' equity	319,381	427,009
Noncontrolling interests	6,610	5,799
Total stockholders' investment	325,991	432,808
Total liabilities, redeemable noncontrolling interests and stockholders’ investment	2,475,752	2,222,061
Consolidations, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	(132)	0	$ (1,864)	$ (446)
Accounts Receivable, Net, Current	(1,079,358)	(908,555)
Inventories	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	0	0
Total current assets	(1,079,490)	(908,555)
Intercompany investment	(1,637,198)	(1,521,727)
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	(1,241,218)	(1,184,335)
Total property and equipment, at cost	0	0
Less - Accumulated depreciation and amortization	0	0
Property, Plant and Equipment, Net	0	0
Goodwill	0	0
Other assets	(109,008)	0
Total assets	(4,066,914)	(3,614,617)
Accounts payable	(994,429)	(779,199)
Accrued liabilities	(1,060,861)	(18,009)
Current deferred taxes	0	0
Short-term borrowings and current maturities of long-term debt	0	0
Deferred sale leaseback advance	0	0
Total current liabilities	(2,055,290)	(797,208)
Long-term debt, less current maturities	0	0
Intercompany notes payable	(375,746)	(1,296,993)
Accrued pension liabilities	0	0
Other liabilities and deferred credits	(207,753)	(7,452)
Deferred taxes	0	0
Redeemable noncontrolling interests	0	0
Common stock	(27,872)	(27,872)
Additional paid-in capital	(293,339)	(293,339)
Retained earnings	(993,767)	(1,015,502)
Accumulated other comprehensive income (loss)	(113,147)	(176,251)
Treasury shares, at cost	0	0
Total Bristow Group stockholders' equity	(1,428,125)	(1,512,964)
Noncontrolling interests	0	0
Total stockholders' investment	(1,428,125)	(1,512,964)
Total liabilities, redeemable noncontrolling interests and stockholders’ investment	(4,066,914)	(3,614,617)
Land and Building [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	199,082	171,959
Land and Building [Member] | Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	2,830	2,830
Land and Building [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	55,080	50,946
Land and Building [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	141,172	118,183
Land and Building [Member] | Consolidations, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	0	0
Aircraft And Equipment [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	2,453,950	2,493,869
Aircraft And Equipment [Member] | Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	119,381	108,457
Aircraft And Equipment [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	1,038,526	1,114,218
Aircraft And Equipment [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	1,296,043	1,271,194
Aircraft And Equipment [Member] | Consolidations, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total property and equipment, at cost	$ 0	$ 0