Nature of Operations and Summary of Significant Accounting Policies (Details 6) - USD ($) $ in Thousands	Sep. 07, 2005	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Impairment of Long Lived and Intangible Assets
Property and equipment and related assets		$ 5,556,728	$ 4,923,563
Intangible assets		10,499	12,748	$ 14,998
Atlantic Southeast Airlines Inc
Impairment of Long Lived and Intangible Assets
Intangible assets related to acquisition of Atlantic Southeast	$ 33,700
Period for amortization of intangible assets	15 years
Accumulated amortization expense		$ 23,300	$ 21,000