FAIR VALUE DISCLOSURES (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($) aircraft	Sep. 30, 2014 USD ($) aircraft	Sep. 30, 2015 USD ($) aircraft	Sep. 30, 2014 USD ($) aircraft	Mar. 31, 2015 USD ($)	Jul. 13, 2015 USD ($)	Apr. 17, 2015 USD ($)
Fair Value [Line Items]
Inventories	$ 145,731		$ 145,731		$ 147,169
Assets held for sale	41,242		41,242		57,827
Impairment of inventories	0	$ (3,362)	(5,439)	$ (3,362)
Impairment charges on aircraft held for sale	(12,169)	(558)	(22,031)	(3,137)
Goodwill impairment loss	(22,274)		(22,274)
Gain (Loss) on Sale of Assets and Asset Impairment Charges	$ (34,443)	$ (3,920)	$ (49,744)	$ (6,499)
Number of aircraft impaired | aircraft	10	2	11	6
Other accrued liabilities	$ 73,967		$ 73,967		82,605
Other liabilities and deferred credits	26,942		26,942		39,782
Carrying value of total debt	1,003,380		1,003,380		864,422
Fair value of total debt	947,165		947,165		845,524
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent Consideration- beginning balance			38,905
Change in fair value of contingent consideration			266
Payment of contingent consideration			(8,000)	$ 0
Contingent Consideration- ending balance	31,171		31,171		38,905
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	345,320		345,320		381,458
Term Loan
Fair Value [Line Items]
Carrying value of total debt	342,611		342,611		222,179		$ 222,600
Fair value of total debt	342,611		342,611		222,179
Revolving Credit Facility
Fair Value [Line Items]
Carrying value of total debt	223,800		223,800		83,800
Fair value of total debt	223,800		223,800		83,800
Other debt | Eastern Airways
Fair Value [Line Items]
Carrying value of total debt	14,595		14,595		19,680
Fair value of total debt	14,595		14,595		19,680
Other debt | Convertible Senior Notes Due 2038
Fair Value [Line Items]
Carrying value of total debt	0		0		114,109	$ 1,900
Fair value of total debt	0		0		115,288
Other debt | Airnorth
Fair Value [Line Items]
Carrying value of total debt	20,839		20,839		23,119
Fair value of total debt	20,839		$ 20,839		$ 23,119
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	2,219		$ 2,219		$ 2,379
Total Assets Recurring	2,219		2,219		2,379
Other accrued liabilities	28,727		28,727		33,938
Other liabilities and deferred credits	2,444		2,444		4,967
Total Liabilities Recurring	31,171		31,171		38,905
Fair Value, Measurements, Recurring | Cougar
Fair Value [Line Items]
Total Liabilities Recurring	25,000		25,000		32,500
Fair Value, Measurements, Recurring | Airnorth
Fair Value [Line Items]
Total Liabilities Recurring	6,200		6,200		6,400
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value [Line Items]
Rabbi Trust investments	2,219		2,219		2,379
Total Assets Recurring	2,219		2,219		2,379
Other accrued liabilities	0		0		0
Other liabilities and deferred credits	0		0		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		0		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	28,727		28,727		33,938
Other liabilities and deferred credits	2,444		2,444		4,967
Total Liabilities Recurring	31,171		31,171		$ 38,905
Fair Value, Measurements, Nonrecurring
Fair Value [Line Items]
Inventories	12,118	$ 19,446	12,118	19,446
Assets held for sale	33,647	4,650	33,647	4,650
Goodwill And Other Intangible Assets	52,404		52,404
Total Assets Non Recurring	98,169	24,096	98,169	24,096
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 And Other Intangible Assets	0		0
Total Assets Non Recurring	0	0	0	0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 2
Fair Value [Line Items]
Inventories	12,118	19,446	12,118	19,446
Assets held for sale	33,647	4,650	33,647	4,650
Goodwill And Other Intangible Assets	0		0
Total Assets Non Recurring	45,765	24,096	45,765	24,096
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 And Other Intangible Assets	52,404		52,404
Total Assets Non Recurring	$ 52,404	$ 0	$ 52,404	$ 0