COMMITMENTS AND CONTINGENCIES (Details) (USD $)	6 Months Ended							3 Months Ended			3 Months Ended
	Sep. 30, 2011 number	Oct. 31, 2011 number	Sep. 30, 2011 Remainder of Year 2012 [Member] number	Sep. 30, 2011 Year 2013 [Member] number	Sep. 30, 2011 Year 2014 [Member] number	Sep. 30, 2011 Year 2015 [Member] number	Sep. 30, 2011 Year 2016 and Thereafter [Member] number	Sep. 30, 2011 Commitments [Member] number	Jun. 30, 2011 Commitments [Member] number	Jun. 30, 2010 Commitments [Member] number	Sep. 30, 2011 Options [Member] number	Jun. 30, 2011 Options [Member] number	Jun. 30, 2010 Options [Member] number
Aircraft Purchase Contracts [Line Items]
Aircraft Purchase Commitments - Total	$ 191,955,000		$ 119,894,000	$ 72,061,000	$ 0	$ 0	$ 0
Aircraft Purchase Options - Total	951,254,000		62,939,000	190,158,000	239,964,000	189,251,000	268,942,000
Number of aircraft purchase commitments - Large	10		4	6	0	0	0
Number of aircraft purchase commitments - Total	10		4	6	0	0	0
Number of aircraft purchase options - Medium	12		0	2	4	6	0
Number of aircraft purchase options - Large	25		0	3	7	4	11
Number of aircraft purchase options - Total	37		0	5	11	10	11
Number of signed client contracts	6
Number of aircraft orders cancellable	4
Cancellation Penalty	800,000
Number of aircraft purchase commitments - subsequent event		8
Aircraft purchase commitments - subsequent event		$ 144,000,000
Analysis Of Aircraft Orders And Options [Line Items]
Beginning of quarter								11	6	11	39	31	39
Aircraft delivered								(3)	(2)		0	0
Aircraft ordered								2	3		0	0
New options								0	0		0	19
Exercised options								0	4		3	(4)
Expired options								0	0		(5)	(7)
End of quarter								10	11	11	37	39	39
Collective Bargaining Agreements and/or Unions	52.00%
Employee Agreement Escalation Rate	annual escalations of up to 8.8%
Possible litigation damages from early termination of agreement	The claimants allege that an agreement between the parties was terminated without justification and seek damages of $16.3 million.
Description of Guarantees Given by Parent Company	We have guaranteed the repayment of up to £10 million ($15.6 million) of the debt of FBS Limited, an unconsolidated affiliate, which expires December 31, 2012.