Nature of Operations and Summary of Significant Accounting Policies (Details 4) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2005 Atlantic Southeast Airlines,Inc. Y	Dec. 31, 2012 Atlantic Southeast Airlines,Inc.	Dec. 31, 2011 Atlantic Southeast Airlines,Inc.	Sep. 07, 2005 Atlantic Southeast Airlines,Inc.
Impairment of Long Lived and Intangible Assets
Property and equipment and related assets	$ 2,710,996,000	$ 2,883,475,000
Intangible assets	17,248,000	19,497,000	21,747,000
Intangible assets related to acquisition of Atlantic Southeast							33,700,000
Period for amortization of intangible assets (in years)				15
Accumulated amortization expense					16,500,000	14,300,000
Capitalized Interest
Capitalized interest costs	$ 0	$ 0	$ 5,000