LONG-TERM DEBT - LINE OF CREDIT (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Line of Credit Facility [Line Items]
Line of credit minumum asset requirement amount	$ 500
Secured by aircraft [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100
Line of Credit Facility, Expiration Date	March 2013
Secured by other [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 100
Line of Credit Facility, Expiration Date	March 2016