Commitments and Contingencies (Details) $ in Thousands		9 Months Ended
	Nov. 09, 2017 lease	Sep. 30, 2017 USD ($) item aircraft	Dec. 31, 2016 USD ($)
Commitments to acquire aircraft
Lease contracts, subject to cancellation | lease	0
Minimum aircraft delivery delays that could trigger lessee cancellation clauses (in years)		1 year
Commitments for the acquisition of the aircraft and other equipment
2017 | $		$ 998,592
2018 | $		4,444,854
2019 | $		5,732,940
2020 | $		5,989,309
2021 | $		5,859,304
Thereafter | $		5,063,064
Total | $		$ 28,088,063
Aircrafts
Commitments to acquire aircraft
2017		8
2018		50
2019		78
2020		74
2021		78
Thereafter		84
Total		372
Commitments for the acquisition of the aircraft and other equipment
Total | $		$ 1,600,000	$ 1,300,000
Airbus A321-200
Commitments to acquire aircraft
2018		2
Total		2
Airbus A320/321neo
Commitments to acquire aircraft
2017		2
2018		18
2019		32
2020		26
2021		22
Thereafter		44
Total		144
Number of long-range variants		55
Airbus A330-900neo
Commitments to acquire aircraft
2018		7
2019		5
2020		5
2021		5
Thereafter		5
Total		27
Airbus 350-900/1000
Commitments to acquire aircraft
2017		2
2018		4
2019		2
2020		7
2021		9
Total		24
Airbus A350-1000
Commitments for the acquisition of the aircraft and other equipment
Aircraft to be acquired under non-binding commitment | aircraft		5
Boeing 737-800(2)
Commitments to acquire aircraft
Additional purchase commitments | aircraft		5
Boeing 737 7/8/9 MAX
Commitments to acquire aircraft
2017		2
2018		12
2019		27
2020		27
2021		35
Thereafter		27
Total		130
Boeing 787-9/10
Commitments to acquire aircraft
2017		2
2018		7
2019		12
2020		9
2021		7
Thereafter		8
Total		45