Commitments and Contingencies - Employees (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended					6 Months Ended
	Dec. 31, 2013	Jun. 30, 2014 Health Insurance [Member]	Dec. 31, 2013 Health Insurance [Member]	Jul. 08, 2014 Subsequent Event [Member] airport	Jul. 08, 2014 International Association Of Machinists And Aerospace Workers (IAM) [Member] Subsequent Event [Member] airport	Jun. 30, 2014 Unionized Employees Concentration Risk [Member] Number of Employees, Total [Member]	Jun. 30, 2014 Unionized Employees Concentration Risk [Member] Number of Employees, Total [Member] Air Line Pilots Association, International [Member]	Jun. 30, 2014 Unionized Employees Concentration Risk [Member] Number of Employees, Total [Member] Association of Flight Attendants [Member]	Jun. 30, 2014 Unionized Employees Concentration Risk [Member] Number of Employees, Total [Member] Transport Workers Union [Member]
Concentration Risk [Line Items]
Company's employees covered under collective bargaining agreements (as a percent)						59.00%	24.00%	34.00%	1.00%
Collective bargaining agreement, contract term	5 years
Number of airports in which entity operates				55	4
Liability for Claims and Claims Adjustment Expense [Line Items]
Accrued health care claims		$ 2.2	$ 2.1