Schedule of Property and Equipment (Details) (USD $)	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	$ 1,126,884,000		$ 1,065,600,000
Accumulated depreciation	(348,771,000)		(316,687,000)
Property and equipment, net	778,113,000		748,913,000
Aircraft and engines held for sale	5,474,000		9,831,000
Proceeds from the disposal of aircraft and engines	2,482,000	223,000
Aircraft and flight equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	1,073,054,000		1,012,000,000
Support equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	51,499,000		51,297,000
Vehicles and other equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	1,577,000		1,589,000
Leasehold improvements [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Property and equipment, gross	754,000		714,000
CAM [Member] | Aircraft and flight equipment [Member]
Property, Plant and Equipment, Net, by Type [Abstract]
Leased aircraft, carrying value	$ 303,000,000		$ 316,400,000