FAIR VALUE DISCLOSURES (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($) aircraft	Sep. 30, 2015 USD ($) aircraft	Sep. 30, 2016 USD ($) aircraft	Sep. 30, 2015 USD ($) aircraft	Mar. 31, 2015	Mar. 31, 2016 USD ($)
Fair Value [Line Items]
Inventories	$ 126,973		$ 126,973			$ 142,503
Assets held for sale	40,338		40,338			43,783
Goodwill	28,922		28,922			29,990
Impairment of inventories	(7,572)	$ 0	(7,572)	$ (5,439)
Impairment charges on aircraft held for sale	(1,011)	(12,169)	(11,160)	(22,031)
Goodwill impairment loss		(22,274)		(22,274)
Gain (loss) on sale of assets and asset impairment charges	$ (8,583)	$ (34,443)	$ (18,732)	$ (49,744)
Number of aircraft impaired | aircraft	6	10	13	11
Other accrued liabilities	$ 49,760		$ 49,760			48,392
Other liabilities and deferred credits	25,137		25,137			33,273
Contingent consideration- beginning balance			32,591
Change in fair value of contingent consideration			761
Payment of contingent consideration			(10,000)
Reclass of contingent consideration			(16,000)
Contingent consideration- ending balance	7,352		7,352
Carrying value of total debt	1,230,457		1,230,457			1,140,889
Fair value of total debt	1,123,046		1,123,046			1,016,413
Senior Notes | Senior Notes Due 2022
Fair Value [Line Items]
Carrying value of total debt	401,535		401,535			401,535
Fair value of total debt	294,124		294,124			277,059
Term Loan
Fair Value [Line Items]
Carrying value of total debt	321,720		321,720			335,665
Fair value of total debt	321,720		321,720			335,665
Term Loan Credit Facility
Fair Value [Line Items]
Carrying value of total debt	200,000		200,000			200,000
Fair value of total debt	200,000		200,000			200,000
Revolving Credit Facility
Fair Value [Line Items]
Carrying value of total debt	233,450		233,450			144,000
Fair value of total debt	233,450		233,450			144,000
Other debt
Fair Value [Line Items]
Carrying value of total debt	40,521		40,521			24,394
Fair value of total debt	40,521		40,521			24,394
Other debt | Airnorth
Fair Value [Line Items]
Carrying value of total debt	18,284		18,284			19,652
Fair value of total debt	18,284		18,284			19,652
Other debt | Eastern Airways
Fair Value [Line Items]
Carrying value of total debt	14,947		14,947			15,643
Fair value of total debt	14,947		$ 14,947			15,643
Cougar
Fair Value [Line Items]
Fair value inputs, discount rate			4.00%		4.00%
Airnorth
Fair Value [Line Items]
Fair value inputs, discount rate			2.00%		2.00%
Fair Value, Measurements, Recurring
Fair Value [Line Items]
Rabbi Trust investments	3,190		$ 3,190			2,990
Total assets recurring	3,190		3,190			2,990
Other accrued liabilities	7,352		7,352			29,522
Other liabilities and deferred credits						3,069
Total liabilities recurring	7,352		7,352			32,591
Fair Value, Measurements, Recurring | Cougar
Fair Value [Line Items]
Total liabilities recurring						26,000
Fair Value, Measurements, Recurring | Airnorth
Fair Value [Line Items]
Total liabilities recurring	7,400		7,400			6,600
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value [Line Items]
Rabbi Trust investments	3,190		3,190			2,990
Total assets recurring	3,190		3,190			2,990
Other accrued liabilities	0		0			0
Other liabilities and deferred credits						0
Total liabilities recurring	0		0			0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value [Line Items]
Rabbi Trust investments	0		0			0
Total assets recurring	0		0			0
Other accrued liabilities	0		0			0
Other liabilities and deferred credits						0
Total liabilities recurring	0		0			0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value [Line Items]
Rabbi Trust investments	0		0			0
Total assets recurring	0		0			0
Other accrued liabilities	7,352		7,352			29,522
Other liabilities and deferred credits						3,069
Total liabilities recurring	7,352		7,352			$ 32,591
Fair Value, Measurements, Nonrecurring
Fair Value [Line Items]
Inventories	56,355	$ 12,118	56,355	$ 12,118
Assets held for sale	40,338	33,647	40,338	33,647
Goodwill		52,404		52,404
Total assets non-recurring	96,693	98,169	96,693	98,169
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 1
Fair Value [Line Items]
Inventories	0	0	0	0
Assets held for sale	0	0	0	0
Goodwill		0		0
Total assets non-recurring	0	0	0	0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 2
Fair Value [Line Items]
Inventories	56,355	12,118	56,355	12,118
Assets held for sale	40,338	33,647	40,338	33,647
Goodwill		0		0
Total assets non-recurring	96,693	45,765	96,693	45,765
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value [Line Items]
Inventories	0	0	0	0
Assets held for sale	0	0	0	0
Goodwill		52,404		52,404
Total assets non-recurring	$ 0	$ 52,404	$ 0	$ 52,404