BASIS OF PRESENTATION, CONSOLIDATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	3 Months Ended		6 Months Ended
	Sep. 30, 2016 USD ($) aircraft Customer	Sep. 30, 2015 USD ($) aircraft	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($) aircraft Customer	Sep. 30, 2015 USD ($) aircraft	Mar. 31, 2016 USD ($) Customer	Nov. 01, 2015
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency transaction gain (loss)	$ 2,900,000	$ (11,400,000)		$ (3,400,000)	$ (7,600,000)
Interest income	235,000	217,000		469,000	438,000
Interest expense	(11,703,000)	(7,396,000)		(22,823,000)	(15,286,000)
Interest expense, net	(11,468,000)	(7,179,000)		(22,354,000)	(14,848,000)
Accretion of redeemable noncontrolling interests	0	(4,803,000)		0	1,498,000
Allowance for doubtful accounts	5,000,000			5,000,000		$ 5,600,000
Inventory allowance	29,200,000			29,200,000		27,800,000
Deferred set-up costs, current	14,600,000			14,600,000		12,100,000
Expense of deferred set-up costs	3,500,000			5,700,000
Goodwill impairment		22,274,000			22,274,000
Impairment of inventories	7,572,000	$ 0		7,572,000	$ 5,439,000
Goodwill - beginning balance			$ 28,922,000	29,990,000
Goodwill, foreign currency translation				(1,068,000)
Goodwill - ending balance	28,922,000			28,922,000
Accumulated goodwill impairment loss	42,200,000			42,200,000		42,200,000
Other intangible asset, gross - beginning balance			27,411,000	27,858,000
Other intangible asset, foreign currency translation				(447,000)
Other intangible asset, gross - ending balance	27,411,000			27,411,000
Other intangible asset, accumulated amortization - beginning balance			(21,037,000)	(20,379,000)
Other intangible asset - amortization expense				(658,000)
Other intangible asset, accumulated amortization - ending balance	(21,037,000)			$ (21,037,000)
Weighted average remaining contractual life, in years				5 years 10 months 8 days
Other intangible asset, amortization expense, remainder of fiscal year 2017	441,000			$ 441,000
Other intangible asset, amortization expense, year 2018	872,000			872,000
Other intangible asset, amortization expense, year 2019	744,000			744,000
Other intangible asset, amortization expense, year 2020	456,000			456,000
Other intangible asset, amortization expense, year 2021	456,000			456,000
Other intangible asset, amortization expense, thereafter	3,405,000			3,405,000
Other intangible asset, net	6,374,000			6,374,000
Deferred contract acquisition cost, non current	$ 51,300,000			$ 51,300,000		55,100,000
Number of aircraft delivered | aircraft	6	1		6	3
Capital expenditures	$ 80,803,000	$ 79,212,000		$ 101,866,000	$ 146,989,000
Payments for PP&E	$ 63,700,000	$ 36,000,000		$ 66,800,000	$ 64,300,000
Number of aircraft sold or disposed of | aircraft	0	4		6	13
Proceeds from sale or disposal of assets	$ 329,000	$ 6,806,000		$ 11,819,000	$ 16,107,000
Gain (loss) on disposal of assets	$ (2,186,000)	$ (14,007,000)		$ (12,203,000)	$ (21,702,000)
Number of aircraft impaired | aircraft	6	10		13	11
Impairment charges on aircraft held for sale	$ 1,011,000	$ 12,169,000		$ 11,160,000	$ 22,031,000
Accelerated depreciation	$ 1,300,000	$ 10,500,000		$ 8,200,000	$ 19,300,000
Number of aircraft in exit plan | aircraft	6	21		11	21
Unamortized debt issuance cost	$ 8,911,000			$ 8,911,000		8,917,000
Revenue	357,467,000	$ 446,911,000		726,865,000	$ 913,907,000
Operating expense	(374,772,000)	(425,103,000)		(764,218,000)	(880,427,000)
Earnings from unconsolidated affiliates, net of losses	181,000	(15,360,000)		4,011,000	(9,064,000)
Loss before provision for income taxes	(35,347,000)	(48,436,000)		(78,657,000)	(47,432,000)
Provision (benefit) for income taxes	5,240,000	2,756,000		7,478,000	123,000
Net income	(30,107,000)	(45,680,000)		(71,179,000)	(47,309,000)
Total stockholders' investment	1,416,201,000			1,416,201,000		1,509,892,000
Forecast
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Accelerated depreciation			2,200,000
Aircraft
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Capital expenditures	78,087,000	70,691,000		95,574,000	111,153,000
Gain (loss) on disposal of assets	(1,175,000)	(1,838,000)		(1,043,000)	329,000
Other property plant and equipment
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Capital expenditures	$ 2,716,000	$ 8,521,000		$ 6,292,000	$ 35,836,000
Medium aircraft
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Number of aircraft delivered | aircraft	5	0		5	1
SAR Aircraft
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Number of aircraft delivered | aircraft	1	1		1	2
Client contracts
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Other intangible asset, gross - beginning balance			8,170,000	$ 8,170,000
Other intangible asset, foreign currency translation				0
Other intangible asset, gross - ending balance	$ 8,170,000			8,170,000
Other intangible asset, accumulated amortization - beginning balance			(8,143,000)	(8,062,000)
Other intangible asset - amortization expense				(81,000)
Other intangible asset, accumulated amortization - ending balance	(8,143,000)			$ (8,143,000)
Weighted average remaining contractual life, in years				2 months
Customer relationships
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Other intangible asset, gross - beginning balance			12,780,000	$ 12,779,000
Other intangible asset, foreign currency translation				1,000
Other intangible asset, gross - ending balance	12,780,000			12,780,000
Other intangible asset, accumulated amortization - beginning balance			(10,899,000)	(10,600,000)
Other intangible asset - amortization expense				(299,000)
Other intangible asset, accumulated amortization - ending balance	(10,899,000)			$ (10,899,000)
Weighted average remaining contractual life, in years				5 years
Trade names and trademarks
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Other intangible asset, gross - beginning balance			4,619,000	$ 5,008,000
Other intangible asset, foreign currency translation				(389,000)
Other intangible asset, gross - ending balance	4,619,000			4,619,000
Other intangible asset, accumulated amortization - beginning balance			(777,000)	(636,000)
Other intangible asset - amortization expense				(141,000)
Other intangible asset, accumulated amortization - ending balance	(777,000)			$ (777,000)
Weighted average remaining contractual life, in years				13 years 7 months
Internally developed software
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Other intangible asset, gross - beginning balance			1,086,000	$ 1,149,000
Other intangible asset, foreign currency translation				(63,000)
Other intangible asset, gross - ending balance	1,086,000			1,086,000
Other intangible asset, accumulated amortization - beginning balance			(587,000)	(480,000)
Other intangible asset - amortization expense				(107,000)
Other intangible asset, accumulated amortization - ending balance	(587,000)			$ (587,000)
Weighted average remaining contractual life, in years				2 years 3 months
Licensing
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Other intangible asset, gross - beginning balance			756,000	$ 752,000
Other intangible asset, foreign currency translation				4,000
Other intangible asset, gross - ending balance	756,000			756,000
Other intangible asset, accumulated amortization - beginning balance			(631,000)	(601,000)
Other intangible asset - amortization expense				(30,000)
Other intangible asset, accumulated amortization - ending balance	(631,000)			$ (631,000)
Weighted average remaining contractual life, in years				2 years 1 month
Europe Caspian
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Goodwill - beginning balance			9,062,000	$ 10,026,000
Goodwill, foreign currency translation				(964,000)
Goodwill - ending balance	9,062,000			9,062,000
Accumulated goodwill impairment loss	25,200,000			25,200,000		25,200,000
Accelerated depreciation	200,000			400,000
Revenue	193,725,000	$ 226,183,000		390,688,000	$ 449,524,000
Africa
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Accumulated goodwill impairment loss	6,200,000			6,200,000		6,200,000
Accelerated depreciation	1,100,000	6,500,000		3,900,000	8,800,000
Revenue	51,644,000	65,301,000		105,906,000	144,216,000
Americas
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Accumulated goodwill impairment loss	600,000			600,000		600,000
Accelerated depreciation		3,200,000		3,900,000	6,100,000
Revenue	57,207,000	73,578,000		116,251,000	153,830,000
Asia Pacific
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Goodwill - beginning balance			$ 19,860,000	19,964,000
Goodwill, foreign currency translation				(104,000)
Goodwill - ending balance	19,860,000			19,860,000
Accelerated depreciation		800,000			4,400,000
Revenue	55,256,000	78,693,000		114,400,000	159,081,000
Corporate And Other
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Accumulated goodwill impairment loss	10,200,000			10,200,000		$ 10,200,000
Revenue	$ 2,676,000	6,226,000		$ 5,892,000	15,153,000
Nigeria
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Number of uncollectible receivables | Customer	2			2		2
Australia
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Number of uncollectible receivables | Customer	1			1		1
Unconsolidated affiliate
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency transaction gain (loss)	$ (1,300,000)	$ (19,900,000)		$ (1,300,000)	$ (18,200,000)
Affiliated entity
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Allowance for doubtful accounts	$ 0			$ 0		$ 0
One British Pound Sterling Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.30	1.51		1.30	1.51
One British Pound Sterling Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.30	1.51		1.30	1.51
One British Pound Sterling Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.34	1.57		1.34	1.57
One British Pound Sterling Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.48	1.59		1.48	1.59
One British Pound Sterling Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.31	1.55		1.31	1.55
One British Pound Sterling Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.37	1.54		1.37	1.54
One British Pound Sterling Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.29	1.51		1.29	1.51
One British Pound Sterling Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.29	1.46		1.29	1.46
One Euro Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.12	1.12		1.12	1.12
One Euro Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.12	1.12		1.12	1.12
One Euro Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.13	1.16		1.13	1.16
One Euro Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.15	1.16		1.15	1.16
One Euro Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.12	1.11		1.12	1.11
One Euro Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.12	1.11		1.12	1.11
One Euro Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.10	1.09		1.10	1.09
One Euro Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	1.10	1.06		1.10	1.06
One Australian Dollar Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.77	0.70		0.77	0.70
One Australian Dollar Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.77	0.70		0.77	0.70
One Australian Dollar Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.77	0.77		0.77	0.77
One Australian Dollar Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.78	0.81		0.78	0.81
One Australian Dollar Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.76	0.73		0.76	0.73
One Australian Dollar Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.75	0.75		0.75	0.75
One Australian Dollar Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.74	0.69		0.74	0.69
One Australian Dollar Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.72	0.69		0.72	0.69
One Norwegian Kroner Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1251	0.1176		0.1251	0.1176
One Norwegian Kroner Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1251	0.1176		0.1251	0.1176
One Norwegian Kroner Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1251	0.1272		0.1251	0.1272
One Norwegian Kroner Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1251	0.1370		0.1251	0.1370
One Norwegian Kroner Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1201	0.1220		0.1201	0.1220
One Norwegian Kroner Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1206	0.1255		0.1206	0.1255
One Norwegian Kroner Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1163	0.1171		0.1163	0.1171
One Norwegian Kroner Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.1163	0.1171		0.1163	0.1171
One Nigerian Naira Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0032	0.0051		0.0032	0.0051
One Nigerian Naira Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0032	0.0051		0.0032	0.0051
One Nigerian Naira Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0036	0.0051		0.0036	0.0051
One Nigerian Naira Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0050	0.0051		0.0050	0.0051
One Nigerian Naira Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0032	0.0051		0.0032	0.0051
One Nigerian Naira Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0040	0.0051		0.0040	0.0051
One Nigerian Naira Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0029	0.0050		0.0029	0.0050
One Nigerian Naira Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.0029	0.0050		0.0029	0.0050
One Brazilian Real Into US Dollars | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.3078	0.2441		0.3078	0.2441
One Brazilian Real Into US Dollars | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.3078	0.2441		0.3078	0.2441
One Brazilian Real Into US Dollars | Maximum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.3191	0.3217		0.3191	0.3217
One Brazilian Real Into US Dollars | Maximum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.3191	0.3435		0.3191	0.3435
One Brazilian Real Into US Dollars | Weighted average | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.3083	0.2858		0.3083	0.2858
One Brazilian Real Into US Dollars | Weighted average | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.2966	0.3057		0.2966	0.3057
One Brazilian Real Into US Dollars | Minimum | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.2991	0.2406		0.2991	0.2406
One Brazilian Real Into US Dollars | Minimum | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Foreign currency exchange rates	0.2702	0.2406		0.2702	0.2406
Impact of Changes in Foreign Currency Exchange Rates | Quarter To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Revenue	$ (24,655,000)
Operating expense	21,670,000
Earnings from unconsolidated affiliates, net of losses	18,640,000
Non-operating expense	14,286,000
Loss before provision for income taxes	29,941,000
Provision (benefit) for income taxes	(8,865,000)
Net income	21,076,000
Cumulative translation adjustment	(5,962,000)
Total stockholders' investment	15,114,000			$ 15,114,000
Impact of Changes in Foreign Currency Exchange Rates | Year To Date
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Revenue				(38,032,000)
Operating expense				36,471,000
Earnings from unconsolidated affiliates, net of losses				16,852,000
Non-operating expense				4,169,000
Loss before provision for income taxes				19,460,000
Provision (benefit) for income taxes				(6,027,000)
Net income				13,433,000
Cumulative translation adjustment				(17,539,000)
Total stockholders' investment	$ (4,106,000)			$ (4,106,000)
Airnorth
Basis of Presentation, Consolidation and Summary of Significant Accounting Policies [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired							15.00%