Commitments and Contingencies - Schedule of Future Aircraft Operating Leases (Details)	Dec. 31, 2016 aircraft
Long-term Purchase Commitment [Line Items]
2017	15
2018	14
2019	13
2020	16
2021	18
Total future aircraft to be received	76
Airbus | A320
Long-term Purchase Commitment [Line Items]
2017	4
2018	5
2019	1
Total future aircraft to be received	10
Airbus | A320NEO
Long-term Purchase Commitment [Line Items]
2018	4
2019	12
2020	16
2021	18
Total future aircraft to be received	50
Airbus | A321
Long-term Purchase Commitment [Line Items]
2017	11
2018	5
Total future aircraft to be received	16