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Number Of Delivered Aircraft Financed With Debt

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt and Other Obligations (Details) $ in Millions	3 Months Ended		9 Months Ended
Debt and Other Obligations (Details) $ in Millions	Sep. 30, 2019 USD ($) aircraft	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) aircraft	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Future Aircraft To Be Received \| aircraft	56		56
Long-term debt	$ 2,203.3		$ 2,203.3		$ 2,234.5
Less current maturities	193.7		193.7		162.8
Less unamortized discounts, net	42.0		42.0		47.7
Total	1,967.6		1,967.6		2,024.0
Repayments of debt obligations	40.1	$ 32.6	125.9	$ 93.2
Senior Loans [Member]
Debt Instrument [Line Items]
Long-term debt	$ 354.7		$ 354.7		$ 382.4
Weighted-average interest rate	4.10%		4.10%		4.10%
Junior Loans [Member]
Debt Instrument [Line Items]
Long-term debt	$ 24.6		$ 24.6		$ 31.1
Weighted-average interest rate	6.90%		6.90%		6.90%
Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Principal amount	$ 70.0		$ 70.0
Long-term debt	$ 660.0		$ 660.0		$ 625.1
Weighted-average interest rate	3.48%		3.48%		3.88%
Equipment Notes, Series A 2015-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 363.6		$ 363.6		$ 378.6
Weighted-average interest rate	4.10%		4.10%		4.10%
Equipment Notes, Series B 2015-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 76.0		$ 76.0		$ 80.0
Weighted-average interest rate	4.45%		4.45%		4.45%
Equipment Notes, Series C 2015-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 103.8		$ 103.8		$ 109.5
Weighted-average interest rate	4.93%		4.93%		4.93%
Equipment Notes, Series AA 2017-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 228.4		$ 228.4		$ 242.5
Weighted-average interest rate	3.38%		3.38%		3.38%
Equipment Notes, Series A 2017-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 76.1		$ 76.1		$ 80.8
Weighted-average interest rate	3.65%		3.65%		3.65%
Equipment Notes, Series B 2017-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 70.6		$ 70.6		$ 83.7
Weighted-average interest rate	3.80%		3.80%		3.80%
Equipment Notes, Series C 2017-1 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 85.5		$ 85.5		$ 85.5
Weighted-average interest rate	5.11%		5.11%		5.11%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt	$ 160.0		$ 160.0		$ 135.3
Weighted-average interest rate	3.45%		3.45%		3.72%
Fixed Rate Loan [Member] \| Maximum
Debt Instrument [Line Items]
Long-term debt, term	12 years		12 years
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 160.0		$ 160.0
Airbus [Member] \| Airbus A320 [Member] \| Fixed Rate Loan [Member]
Debt Instrument [Line Items]
Number of delivered aircraft financed with debt \| aircraft			2
Airbus [Member] \| A-320-Neo [Member]
Debt Instrument [Line Items]
Future Aircraft To Be Received \| aircraft	42		42
Airbus [Member] \| A-320-Neo [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Future Aircraft To Be Received \| aircraft	40		40