Commitments and Contingencies - Schedule of Future Aircraft Operating Leases (Details)	Jun. 30, 2018 aircraft
Long-term Purchase Commitment [Line Items]
remainder of 2018	7
2019	11
2020	16
2021	18
Total future aircraft to be received	52
Airbus [Member] | A320 [Member]
Long-term Purchase Commitment [Line Items]
remainder of 2018	7
2019	2
2020
Total future aircraft to be received	9
Airbus [Member] | A320NEO [Member]
Long-term Purchase Commitment [Line Items]
2019	9
2020	16
2021	18
Total future aircraft to be received	43