SUPPLEMENTAL CONDENSED CONSOLIDATING FINANCIAL INFORMATION BS (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$ 96,656	$ 104,310	$ 104,146	$ 204,341
Accounts receivable	206,915	249,317
Inventories	124,911	142,503
Assets held for sale	38,246	43,783
Prepaid expenses and other current assets	41,143	53,183
Total current assets	507,871	593,096
Intercompany investment	0	0
Investment in unconsolidated affiliates	210,162	194,952
Intercompany notes receivable	0	0
Land and buildings	231,448	253,098
Aircraft and equipment	2,622,701	2,570,577
Total property and equipment, at cost	2,854,149	2,823,675
Less - Accumulated depreciation and amortization	(599,785)	(540,423)
Total property and equipment, net	2,254,364	2,283,252
Goodwill	19,798	29,990	75,628
Other assets	121,652	161,655
Total assets	3,113,847	3,262,945
Accounts payable	98,215	96,966
Accrued liabilities	186,246	201,605
Deferred taxes	830	1,881
Short-term borrowings and current maturities of long-term debt	131,063	60,394
Contingent consideration	0	29,522
Total current liabilities	416,354	390,368
Long-term debt, less current maturities	1,150,956	1,071,578
Intercompany notes payable	0	0
Accrued pension liabilities	61,647	70,107
Other liabilities and deferred credits	28,899	33,273
Deferred taxes	154,873	172,254
Redeemable noncontrolling interest	6,886	15,473
Common stock	379	377
Additional paid-in capital	809,995	801,173
Retained earnings	991,906	1,172,273
Accumulated other comprehensive income (loss)	(328,277)	(289,819)	(270,329)	(156,506)
Treasury stock	(184,796)	(184,796)
Total Bristow Group stockholders' investment	1,289,207	1,499,208
Noncontrolling interests	5,025	10,684
Total stockholders' investment	1,294,232	1,509,892
Total liabilities, redeemable noncontrolling interest and stockholders' investment	3,113,847	3,262,945
Eliminations
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	0	0	0	(446)
Accounts receivable	(370,603)	(1,247,016)
Inventories	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	(10,451)	0
Total current assets	(381,054)	(1,247,016)
Intercompany investment	(2,722,362)	(2,457,119)
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	(383,980)	(170,465)
Land and buildings	0	0
Aircraft and equipment	0	0
Total property and equipment, at cost	0	0
Less - Accumulated depreciation and amortization	0	0
Total property and equipment, net	0	0
Goodwill	0	0
Other assets	0	0
Total assets	(3,487,396)	(3,874,600)
Accounts payable	(355,442)	(883,242)
Accrued liabilities	(25,628)	(257,683)
Deferred taxes	0	0
Short-term borrowings and current maturities of long-term debt	0	0
Contingent consideration	0	0
Total current liabilities	(381,070)	(1,140,925)
Long-term debt, less current maturities	0	0
Intercompany notes payable	(383,980)	(190,374)
Accrued pension liabilities	0	0
Other liabilities and deferred credits	0	0
Deferred taxes	0	0
Redeemable noncontrolling interest	0	0
Common stock	(135,345)	(135,344)
Additional paid-in capital	(313,435)	(293,339)
Retained earnings	(1,611,104)	(1,683,245)
Accumulated other comprehensive income (loss)	(662,462)	(431,373)
Treasury stock	0	0
Total Bristow Group stockholders' investment	(2,722,346)	(2,543,301)
Noncontrolling interests	0	0
Total stockholders' investment	(2,722,346)	(2,543,301)
Total liabilities, redeemable noncontrolling interest and stockholders' investment	(3,487,396)	(3,874,600)
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	3,382	35,241	126	4,640
Accounts receivable	76,383	768,641
Inventories	0	0
Assets held for sale	0	0
Prepaid expenses and other current assets	3,237	5,048
Total current assets	83,002	808,930
Intercompany investment	2,491,631	2,207,516
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	306,641	153,078
Land and buildings	4,806	4,776
Aircraft and equipment	151,005	137,751
Total property and equipment, at cost	155,811	142,527
Less - Accumulated depreciation and amortization	(29,099)	(23,556)
Total property and equipment, net	126,712	118,971
Goodwill	0	0
Other assets	18,770	48,190
Total assets	3,026,756	3,336,685
Accounts payable	231,841	208,230
Accrued liabilities	61,791	26,886
Deferred taxes	(1,272)	88
Short-term borrowings and current maturities of long-term debt	79,053	25,678
Contingent consideration	0	0
Total current liabilities	371,413	260,882
Long-term debt, less current maturities	763,325	1,047,150
Intercompany notes payable	70,689	0
Accrued pension liabilities	0	0
Other liabilities and deferred credits	11,597	12,278
Deferred taxes	112,716	147,631
Redeemable noncontrolling interest	0	0
Common stock	379	377
Additional paid-in capital	809,995	801,173
Retained earnings	991,906	1,172,273
Accumulated other comprehensive income (loss)	78,306	78,306
Treasury stock	(184,796)	(184,796)
Total Bristow Group stockholders' investment	1,695,790	1,867,333
Noncontrolling interests	1,226	1,411
Total stockholders' investment	1,697,016	1,868,744
Total liabilities, redeemable noncontrolling interest and stockholders' investment	3,026,756	3,336,685
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	299	3,393	884	0
Accounts receivable	288,235	353,729
Inventories	34,721	37,185
Assets held for sale	30,716	38,771
Prepaid expenses and other current assets	4,501	(1,843)
Total current assets	358,472	431,235
Intercompany investment	104,435	104,435
Investment in unconsolidated affiliates	0	0
Intercompany notes receivable	37,633	13,787
Land and buildings	62,114	63,976
Aircraft and equipment	1,199,073	1,142,829
Total property and equipment, at cost	1,261,187	1,206,805
Less - Accumulated depreciation and amortization	(258,225)	(238,644)
Total property and equipment, net	1,002,962	968,161
Goodwill	0	0
Other assets	2,139	743
Total assets	1,505,641	1,518,361
Accounts payable	70,434	475,118
Accrued liabilities	17,379	31,371
Deferred taxes	2,102	1,914
Short-term borrowings and current maturities of long-term debt	17,432	0
Contingent consideration	0	0
Total current liabilities	107,347	508,403
Long-term debt, less current maturities	284,710	0
Intercompany notes payable	226,091	108,952
Accrued pension liabilities	0	0
Other liabilities and deferred credits	6,229	6,935
Deferred taxes	40,344	3,670
Redeemable noncontrolling interest	0	0
Common stock	20,028	4,996
Additional paid-in capital	29,387	9,291
Retained earnings	791,117	876,114
Accumulated other comprehensive income (loss)	388	0
Treasury stock	0	0
Total Bristow Group stockholders' investment	840,920	890,401
Noncontrolling interests	0	0
Total stockholders' investment	840,920	890,401
Total liabilities, redeemable noncontrolling interest and stockholders' investment	1,505,641	1,518,361
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	92,975	65,676	$ 103,136	$ 200,147
Accounts receivable	212,900	373,963
Inventories	90,190	105,318
Assets held for sale	7,530	5,012
Prepaid expenses and other current assets	43,856	49,978
Total current assets	447,451	599,947
Intercompany investment	126,296	145,168
Investment in unconsolidated affiliates	210,162	194,952
Intercompany notes receivable	39,706	3,600
Land and buildings	164,528	184,346
Aircraft and equipment	1,272,623	1,289,997
Total property and equipment, at cost	1,437,151	1,474,343
Less - Accumulated depreciation and amortization	(312,461)	(278,223)
Total property and equipment, net	1,124,690	1,196,120
Goodwill	19,798	29,990
Other assets	100,743	112,722
Total assets	2,068,846	2,282,499
Accounts payable	151,382	296,860
Accrued liabilities	132,704	401,031
Deferred taxes	0	(121)
Short-term borrowings and current maturities of long-term debt	34,578	34,716
Contingent consideration	0	29,522
Total current liabilities	318,664	762,008
Long-term debt, less current maturities	102,921	24,428
Intercompany notes payable	87,200	81,422
Accrued pension liabilities	61,647	70,107
Other liabilities and deferred credits	11,073	14,060
Deferred taxes	1,813	20,953
Redeemable noncontrolling interest	6,886	15,473
Common stock	115,317	130,348
Additional paid-in capital	284,048	284,048
Retained earnings	819,987	807,131
Accumulated other comprehensive income (loss)	255,491	63,248
Treasury stock	0	0
Total Bristow Group stockholders' investment	1,474,843	1,284,775
Noncontrolling interests	3,799	9,273
Total stockholders' investment	1,478,642	1,294,048
Total liabilities, redeemable noncontrolling interest and stockholders' investment	$ 2,068,846	$ 2,282,499