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Long-Term Debt and Other Borrowings - Schedule of Long-term Debt (Parenthetical) (Detail) $ in Millions |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 28, 2018 USD ($) | Jun. 27, 2018 USD ($) Aircraft | Jun. 30, 2018 USD ($) Aircraft | Feb. 28, 2018 Engine | Dec. 31, 2017 USD ($) Aircraft | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) Aircraft | Jun. 30, 2018 USD ($) Aircraft | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) Aircraft | Sep. 30, 2015 USD ($) Aircraft | Sep. 30, 2007 USD ($) Aircraft | Sep. 30, 2005 USD ($) Aircraft | Sep. 30, 2004 USD ($) Aircraft | Sep. 30, 2014 USD ($) Aircraft
Flight Equipment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  | $ 8.3 |  |  |  |
Long term debt interest rate percentage |  |  |  |  |  |  |  |  |  |  | 5.163% |  |  |  |
Flight Equipment Maintenance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  | $ 11.9 | $ 11.9 |  | $ 11.9 | $ 11.9 |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Three-month LIBOR plus a spread ranging from 2.93% to 2.96% |  |  |  |  |  |  |
Flight Equipment Maintenance [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.267% |  |  |  |  | 5.267% |  |  |  |  |  |  |
Flight Equipment Maintenance [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  | 2.93% |  |  |  |  |  |  |  |
Flight Equipment Maintenance [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.297% |  |  |  |  | 5.297% |  |  |  |  |  |  |
Flight Equipment Maintenance [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  | 2.96% |  |  |  |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2019 | 2019 |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2022 | 2022 |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2024 | 2024 |  |  |  |  |  |
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2027 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2027 | 2027 |  |  |  |  |  |
Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2028 | 2028 |  |  |  |  |  |
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2028 | 2028 |  |  |  |  |  |
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2022 |  |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2022 | 2022 |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2022 [Member] | Flight Equipment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  | $ 99.1 |  |  | $ 99.1 |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | monthly LIBOR Plus 7.25% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 9.342% |  |  |  |  | 9.342% |  |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2022 [Member] | Flight Equipment [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  | 7.25% |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2020 [Member] | Flight Equipment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2020 | 2020 |  |  |  |  |  |
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2020 [Member] | Flight Equipment Maintenance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2020 | 2020 |  |  |  |  |  |
Notes Payable to Financial Institution Due 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2020 | 2020 |  |  |  |  |  |
Notes Payable to Financial Institution Due 2020 [Member] | Flight Equipment Maintenance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 10.2 |  |  | $ 10.2 | $ 10.2 |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | monthly LIBOR plus 3.07% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.162% |  |  |  |  | 5.162% |  |  |  |  |  |  |
Notes Payable to Financial Institution Due 2020 [Member] | Flight Equipment Maintenance [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  | 3.07% | 3.07% |  |  |  |
Notes Payable to Financial Institution Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2019 | 2019 |  |  |  |  |  |
Working Capital Draw Loan, Collateralized by Certain Flight Equipment and Spare Parts [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 35.0 |  |  | $ 35.0 |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | One-month LIBOR plus 4.25% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 6.342% |  |  |  |  | 6.342% |  |  |  |  |  |  |
Working Capital Draw Loan, Collateralized by Certain Flight Equipment and Spare Parts [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  | 4.25% |  |  |  |  |
Other Obligations Due to Financial Institution, Collateralized by the Underlying Equipment, Due 2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2023 |  |  |  |  |  |  |
Number of spare engines leased | Engine |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |
Imputed interest |  |  |  | 9.13% |  |  |  |  |  |  |  |  |  |  |
Notes Payable to Financial Institution Collateralized By Underlying Equipment Due in 2020 with LIBOR Plus 3.30% [Member] | Flight Equipment Maintenance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  | $ 25.0 |  |  | $ 25.0 |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Three-month LIBOR plus 3.30% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.637% |  |  |  |  | 5.637% |  |  |  |  |  |  |
Notes Payable to Financial Institution Collateralized By Underlying Equipment Due in 2020 with LIBOR Plus 3.30% [Member] | Flight Equipment Maintenance [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  | 3.30% |  |  |  |  |  |
CRJ-900 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft refinanced | Aircraft |  |  | 6 |  | 9 |  |  | 6 |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  | 6 | 9 |  |  |  |  | 9 |  |  |  |  |  |  |
Debt instrument, face amount | $ 69.6 | $ 27.5 | $ 27.5 |  | $ 74.9 |  |  | $ 27.5 |  |  |  |  |  |  |
Long term debt interest rate description | LIBOR plus a spread ranging from 3.50% for the senior promissory notes to 7.50% for the subordinated promissory notes |  |  |  |  |  |  | LIBOR plus 3.50%. |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  | 3.50% |  |  |  |  |  |  |  |  |  |  |  |  |
CRJ-900 [Member] | Capital Lease Obligations [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 69.6 |  |  |  |  | $ 69.6 |  |  |  |  |  |  |
CRJ-900 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  |  | 5 | 9 |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 118.0 |  |
Long term debt interest rate description |  |  |  |  |  |  |  | London InterBank Offered Rate ("LIBOR"), plus 3% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.092% |  |  |  |  | 5.092% |  |  |  |  |  |  |
CRJ-900 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |
CRJ-900 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  | 3 |  |  |
CRJ-900 [Member] | Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2027 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  | 7 |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  | $ 170.2 |  |  |  |
CRJ-900 [Member] | Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument maturity year |  |  |  |  |  |  |  | 2022 |  |  |  |  |  |  |
CRJ-900 [Member] | Senior Notes Due Two Thousand Twenty Seven [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  | $ 151.0 |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | monthly LIBOR plus 2.71% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.802% |  |  |  |  | 4.802% |  |  |  |  |  |  |
CRJ-900 [Member] | Senior Notes Due Two Thousand Twenty Seven [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  |  | 2.71% |  |  |  |
CRJ-900 [Member] | Subordinated Notes Due Two Thousand Twenty Seven [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Imputed interest |  |  |  |  |  |  |  |  |  |  | 6.25% |  |  |  |
Debt discount |  |  |  |  |  |  |  |  |  |  | $ 8.1 |  |  |  |
CRJ-900 [Member] | Senior Notes due Two Thousand Twenty Two [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  | $ 46.9 |  |  |  |  |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  | 3.50 |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.592% |  |  |  |  | 5.592% |  |  |  |  |  |  |
CRJ-900 [Member] | Subordinated Notes DueTwoThousandTwentyTwo [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Monthly LIBOR plus 4.50% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 6.592% |  |  |  |  | 6.592% |  |  |  |  |  |  |
CRJ-900 [Member] | Subordinated Notes DueTwoThousandTwentyTwo [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  | 4.50% |  |  |  |  |  |  |  |  |  |
CRJ-900 [Member] | Senior Notes Due 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 67.3 |  |  |  |  | $ 67.3 |  |  |  |  |  |  |
Long term debt basis spread on variable rate | 3.50% |  | 3.50% |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.837% |  |  |  |  | 5.837% |  |  |  |  |  |  |
CRJ-900 [Member] | Senior Notes Due 2020 [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Three-month LIBOR plus 3.50% |  |  |  |  |  |  |
CRJ-900 [Member] | Subordinated Notes Due 2020 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate | 7.50% |  | 7.50% |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 9.837% |  |  |  |  | 9.837% |  |  |  |  |  |  |
CRJ-900 [Member] | Subordinated Notes Due 2020 [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Three month LIBOR plus 7.50% |  |  |  |  |  |  |
CRJ-700 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 |
CRJ-700 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  | 3 |  |  |
Five C- R- J-700 and Nine C- R- J-900 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 254.7 |
Long term debt interest rate description |  |  |  |  |  |  |  | Monthly LIBOR plus 3% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 5.092% |  |  |  |  | 5.092% |  |  |  |  |  |  |
Five C- R- J-700 and Nine C- R- J-900 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2019 [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |
Three C- R- J-900 and Three C- R- J-700 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  | $ 120.3 |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Monthly LIBOR plus 2.25% |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.342% |  |  |  |  | 4.342% |  |  |  |  |  |  |
Three C- R- J-900 and Three C- R- J-700 [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  |  |  | 2.25% |  |  |
Ten C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 88.4
Long term debt interest rate description |  |  |  |  |  |  |  | monthly LIBOR plus a spread ranging from 1.95% to 7.25% |  |  |  |  |  |  |
Ten C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.042% |  |  |  |  | 4.042% |  |  |  |  |  |  |
Ten C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  | 1.95% |  |  |  |  |  |  |
Ten C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 9.342% |  |  |  |  | 9.342% |  |  |  |  |  |  |
Ten C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2022 [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  | 7.25% |  |  |  |  |  |  |
Eight C- R- J-900 Aircraft [Member] | Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2024 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8
Debt instrument, face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 114.5
Long term debt interest rate percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5.00%
Ten E-175 Aircraft [Member] | Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  | 10 |  |  | 10 |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 246.0 |  |  | $ 246.0 |  |  |  |  |
Ten E-175 Aircraft [Member] | Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.75% |  |  |  |  | 4.75% |  |  |  |  |  |  |
Ten E-175 Aircraft [Member] | Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 6.25% |  |  |  |  | 6.25% |  |  |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of aircraft financed | Aircraft |  |  |  |  |  |  | 8 |  |  | 8 |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 195.3 |  |  | $ 195.3 |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior Notes Due 2008 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate description |  |  |  |  |  |  |  | Three-month LIBOR plus a spread ranging from 2.20% to 2.32% |  |  |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior Notes Due 2008 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  | $ 172.0 |  |  | $ 172.0 |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.537% |  |  |  | 2.32% | 4.537% |  | 2.32% |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior Notes Due 2008 [Member] | Minimum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  | 2.20% |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior Notes Due 2008 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.657% |  |  |  |  | 4.657% |  |  |  |  |  |  |
Eight E-175 Aircraft [Member] | Senior Notes Due 2008 [Member] | Maximum [Member] | LIBOR [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt basis spread on variable rate |  |  |  |  |  |  |  |  |  | 2.32% |  |  |  |  |
Eight E-175 Aircraft [Member] | Subordinated Notes Due 2008 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long term debt interest rate percentage |  |  | 4.50% |  |  |  |  | 4.50% |  |  |  |  |  |  |

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