Impact of COVID-19 - Workforce Reduction Narrative (Details) - COVID-19 Pandemic $ in Millions	1 Months Ended	2 Months Ended	3 Months Ended
	Jul. 31, 2020 aircraft	Oct. 02, 2020	Sep. 30, 2020 USD ($)
Unusual or Infrequent Item, or Both [Line Items]
Severance costs and costs for voluntary separations | $			$ 2.4
Subsequent Event
Unusual or Infrequent Item, or Both [Line Items]
Involuntary terminated employees reduction due to voluntary leave program, percent (more than)		95.00%
U.S. Based Union Employees
Unusual or Infrequent Item, or Both [Line Items]
Expected number of positions to be eliminated | aircraft	2,500