ACQUISITIONS (Details)	3 Months Ended								12 Months Ended			0 Months Ended		12 Months Ended						0 Months Ended				12 Months Ended					0 Months Ended
	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2013 USD ($)	Jun. 30, 2013 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Mar. 31, 2013 USD ($)	Jan. 29, 2015 Airnorth [Member] USD ($)	Jan. 29, 2015 Airnorth [Member] AUD	Mar. 31, 2015 Airnorth [Member] USD ($)	Mar. 31, 2014 Airnorth [Member] USD ($)	Jan. 29, 2015 Airnorth [Member] USD ($) aircraft	Jan. 29, 2015 Airnorth [Member] AUD	Jan. 29, 2015 Airnorth [Member] Turboprop [Member] aircraft	Jan. 29, 2015 Airnorth [Member] Regional Jets [Member] aircraft	Jan. 29, 2015 Airnorth [Member] Call option [Member]	Jan. 29, 2015 Airnorth [Member] Put option [Member]	Feb. 06, 2014 Eastern Airways USD ($)	Feb. 06, 2014 Eastern Airways GBP (£)	Mar. 31, 2015 Eastern Airways USD ($)	Mar. 31, 2014 Eastern Airways USD ($)	Mar. 31, 2013 Eastern Airways USD ($)	Feb. 06, 2014 Eastern Airways USD ($)	Feb. 06, 2014 Eastern Airways GBP (£)	Feb. 06, 2014 Eastern Airways Put option [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired																85.00%	85.00%										60.00%	60.00%
Acquisition cost												$ 24,000,000	30,300,000									$ 44,000,000	£ 27,000,000
Potential earn-out payments	0				0				0	0	34,245,000					13,000,000	17,000,000										10,000,000	6,000,000
Business combination contingent consideration arrangement terms												4 years	4 years									3 years	3 years
Option indexed to issuer's equity, period																				6 months	3 years								7 years
Number Of Aircrafts Owned																13	13	9	4
Assets, Current	637,851,000				721,607,000				637,851,000	721,607,000						15,188,000											21,117,000
Total property and equipment, net	2,157,101,000				2,268,751,000				2,157,101,000	2,268,751,000						39,822,000											63,391,000
Goodwill	75,628,000				56,680,000				75,628,000	56,680,000	28,897,000					24,252,000											26,479,000
Other Assets, Noncurrent	143,764,000				88,604,000				143,764,000	88,604,000						4,403,000											20,474,000
Total assets	3,230,720,000				3,398,257,000				3,230,720,000	3,398,257,000						83,665,000											131,461,000
Liabilities, Current	(435,006,000)				(457,825,000)				(435,006,000)	(457,825,000)						(20,104,000)											(37,644,000)
Total long-term debt	(845,692,000)				(827,095,000)				(845,692,000)	(827,095,000)						(20,606,000)											(20,400,000)
Other liabilities and deferred credits	(39,782,000)				(78,126,000)				(39,782,000)	(78,126,000)						(9,441,000)											(8,239,000)
Total Liabilities																(50,151,000)											(66,283,000)
Temporary equity	26,223,000				22,283,000				26,223,000	22,283,000				3,339,000										22,885,000	22,283,000
Assets, Net																30,087,000											44,039,000
Revenues	450,355,000	460,140,000	475,636,000	472,538,000	440,925,000	412,335,000	417,328,000	398,994,000	1,858,669,000	1,669,582,000	1,508,473,000			11,400,000										144,800,000	21,200,000
Increase (Decrease) in Temporary Equity [Roll Forward]
Temporary equity, beginning balance				22,283,000					22,283,000			3,427,000										21,139,000		22,283,000
Noncontrolling interest expense									3,400,000	700,000				(39,000)										3,389,000	671,000
Currency translation									2,800,000	500,000				(49,000)										(2,787,000)	473,000
Temporary equity, ending balance	26,223,000				22,283,000				26,223,000	22,283,000				3,339,000										22,885,000	22,283,000
Business Acquisition, Pro Forma Revenue														1,927,680,000	1,734,911,000										1,761,390,000	1,625,832,000
Business Acquisition, Pro Forma Net Income (Loss)														$ 87,902,000	$ 187,785,000										$ 188,921,000	$ 144,136,000