Labor and Legal Proceedings - Additional Information (Details) - USD ($) $ in Millions		6 Months Ended
	May 01, 2020	Jun. 30, 2020	Dec. 31, 2019
Brazilian Customs Claim [Member]
Loss Contingencies [Line Items]
Brazilian claims in the aggregate		$ 3.8
Amounts on deposit for Brazilian claims included in deferred costs and other assets		$ 3.1	$ 4.1
Atlas Pilots [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period		5 years
Southern Air Pilots [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period		4 years
Atlas and Polar Dispatchers [Member]
Loss Contingencies [Line Items]
Collective bargaining agreement period		5 years
All Pilots [Member]
Loss Contingencies [Line Items]
Percentage of pay increase to pilots	10.00%