VARIABLE INTEREST ENTITIES (Details) £ / shares in Units, $ in Thousands, £ in Millions	1 Months Ended			3 Months Ended		9 Months Ended
	Apr. 30, 2015	Jul. 31, 2014	Dec. 31, 2013	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) Affiliates People	Dec. 31, 2015 USD ($)	Dec. 31, 2016 GBP (£) voting_rights	Dec. 31, 2016 USD ($) voting_rights	Nov. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	May 31, 2004 USD ($) shares	May 31, 2004 £ / shares	Apr. 30, 2004
Variable Interest Entities And Other Investments [Line Items]
Number of variable interest entities | Affiliates						4
Statement of Financial Position [Abstract]
Cash and cash equivalents					$ 131,908		$ 131,908		$ 71,159		$ 104,310	$ 104,146
Accounts receivable									216,406		249,317
Inventories									124,358		142,503
Prepaid expenses and other current assets									52,148		53,183
Total current assets									501,706		593,096
Investment in unconsolidated affiliates									206,797		194,952
Property, plant and equipment, net									2,262,667		2,283,252
Goodwill									18,793	$ 27,500	29,990
Other assets									141,146		161,655
Total assets									3,131,109		3,262,945
Accounts payable									79,902		96,966
Accrued liabilities									175,393		201,605
Accrued interest									5,699		11,985
Current Maturities of long-term debt									271,461		60,394
Total current liabilities									533,893		390,368
Total long-term debt									990,207		1,071,578
Accrued pension liabilities									49,291		70,107
Other liabilities and deferred credits									26,456		33,273
Deferred taxes									149,961		172,254
Redeemable noncontrolling interest									8,267		15,473
Revenue				$ 337,443	419,887	$ 1,064,308	1,333,794
Net loss				(26,048)	3,568	$ (97,227)	(43,741)
Nigerian Company owned by 100% Nigerian Employees
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, ownership percentage, third party						50.00%
Variable interest entity, purchased percentage from third party	2.00%
Employee Trust Fund
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, ownership percentage, third party						2.00%
Bristow Helicopters Nigeria Ltd
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, purchased percentage from third party	8.00%
Bristow Aviation Holdings Limited
Variable Interest Entities And Other Investments [Line Items]
Ownership percentage in Variable Interest Entity						49.00%
Variable interest entity, ownership percentage, third party						51.00%
Purchase of deferred stock shares | shares													8,000,000
Business acquisition share price | £ / shares														£ 1
Total amount paid for deferred shares													$ 14,400
Principal amount of subordinated unsecured loan stock								£ 91.0	$ 112,400
Interest rate on unsecured loan						13.50%
Deferred interest cost						$ 1,800,000
Call option price held by noncontrolling interest | £								£ 1.0
Call option rate over LIBOR								3.00%	3.00%
Call option guaranteed rate													12.00%
Put option guaranteed rate															10.00%
Statement of Financial Position [Abstract]
Cash and cash equivalents									$ 70,406		62,773
Accounts receivable									549,783		565,223
Inventories									89,097		102,738
Prepaid expenses and other current assets									53,924		53,776
Total current assets									763,210		784,510
Investment in unconsolidated affiliates									3,575		4,676
Property, plant and equipment, net									217,967		251,494
Goodwill									18,792		29,990
Other assets									73,857		82,443
Total assets									1,077,401		1,153,113
Accounts payable									363,665		521,563
Accrued liabilities									128,474		141,977
Accrued interest									1,840,368		1,698,360
Current Maturities of long-term debt									14,063		10,322
Total current liabilities									2,346,570		2,372,222
Total long-term debt									371,425		155,222
Accrued pension liabilities									49,291		70,107
Other liabilities and deferred credits									5,310		7,928
Deferred taxes									13,924		20,330
Redeemable noncontrolling interest									8,266		15,473
Total liabilities									$ 2,794,786		$ 2,641,282
Revenue				291,808	355,036	920,587	1,119,169
Operating loss				(28,287)	(4,906)	(68,803)	(32,479)
Net loss				$ (44,999)	$ (66,425)	$ (214,336)	$ (210,140)
Bristow Aviation Holdings Limited | Caledonia Investments Plc
Variable Interest Entities And Other Investments [Line Items]
Number of voting rights | voting_rights								3	3
Number of board of directors nominations | People						2
Bristow Aviation Holdings Limited | Director one
Variable Interest Entities And Other Investments [Line Items]
Number of voting rights | voting_rights								1	1
Bristow Aviation Holdings Limited | Director two
Variable Interest Entities And Other Investments [Line Items]
Number of voting rights | voting_rights								1	1
Bristow Aviation Holdings Limited | Caledonia Investments Plc
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, ownership percentage, third party						46.00%
Bristow Aviation Holdings Limited | European Union
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, ownership percentage, third party						5.00%
Bristow Helicopters Nigeria Ltd
Variable Interest Entities And Other Investments [Line Items]
Ownership percentage in Variable Interest Entity						48.00%
Nigerian Company owned by 100% Nigerian Employees
Variable Interest Entities And Other Investments [Line Items]
Variable interest entity, purchased percentage from third party		29.00%	19.00%
Pan African Airlines Nigeria Ltd
Variable Interest Entities And Other Investments [Line Items]
Ownership percentage in Variable Interest Entity						50.17%