GENERAL AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - PROPERTY, EQUIPMENT AND DEPRECIATION (DETAILS)	12 Months Ended
	Dec. 31, 2011 years
Buildings [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (in years)	25
Estimated useful life, maximum (in years)	30
Minor building and land improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	10
Computer hardware and software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (in years)	3
Estimated useful life, maximum (in years)	5
Other furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life, minimum (in years)	5
Estimated useful life, maximum (in years)	10
B737 to 400, 700, 800, 900 [Member] | Aircraft [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	20
Q400 [Member] | Aircraft [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)	15