Impact of the COVID-19 Pandemic - Narrative (Details) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	Apr. 22, 2020 USD ($) $ / shares shares	Mar. 16, 2020 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) aircraft	Mar. 31, 2019 USD ($)	Apr. 17, 2020 USD ($)	Dec. 31, 2019 USD ($)
Unusual or Infrequent Item, or Both [Line Items]
Reduction in capacity, percent (more than)			95.00%	95.00%
Aircraft used to secure financing | aircraft				36
Fair value of aircraft used to secure financing			$ 800,000	$ 800,000
Unencumbered assets			800,000	800,000
Goodwill impairment				106,662	$ 0
Long-lived assets			2,298,735	$ 2,298,735			$ 2,316,772
Line of Credit | Revolving Credit Facility
Unusual or Infrequent Item, or Both [Line Items]
Draw down of revolving loans		$ 235,000	$ 235,000
Subsequent Event
Unusual or Infrequent Item, or Both [Line Items]
CARES act funding, tranche one	$ 146,200
Economic Relief Program, maximum financial assistance						$ 364,000
Maximum financial assistance	292,500
Total principal sum	$ 57,800
Warrants issued (in shares) | shares	488,477
Exercise price of warrants (in dollars per share) | $ / shares	$ 11.82
Warrants expiration term	5 years
Coronavirus Aid, Relief, and Economic Security Act Note
Unusual or Infrequent Item, or Both [Line Items]
Term of note			10 years	10 years
Coronavirus Aid, Relief, and Economic Security Act Note | Subsequent Event
Unusual or Infrequent Item, or Both [Line Items]
Interest rate	1.00%
Secured Overnight Financing Rate | Coronavirus Aid, Relief, and Economic Security Act Note | Subsequent Event
Unusual or Infrequent Item, or Both [Line Items]
Margin	2.00%
Minimum | Officer
Unusual or Infrequent Item, or Both [Line Items]
Reduction of salary, percent			10.00%	10.00%
Maximum | Officer
Unusual or Infrequent Item, or Both [Line Items]
Reduction of salary, percent			50.00%	50.00%