Commitments and Contingencies (Tables)

6 Months Ended

Jun. 30, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedules of Concentration of Risk, by Risk Factor

As of June 30, 2018, the flight crewmember employees of ABX and ATI and flight attendant employees of ATI were represented by the labor unions listed below:

Airline	Labor Agreement Unit	Percentage of the Company’s Employees
ABX	International Brotherhood of Teamsters	7.6%
ATI	Air Line Pilots Association	6.9%
ATI	Association of Flight Attendants	1.1%