Longterm Debt Maturities Repayments of Principal in Quarterly Installments Percent

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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.

+ References

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Period Type:	instant

- Definition

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

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-Publisher FASB
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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

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.

+ References

No definition available.

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- Definition

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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Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Debt - Narrative (Details) - USD ($)	12 Months Ended
Debt - Narrative (Details) - USD ($)	Dec. 31, 2019	May 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Long term debt	$ 14,733,000,000		$ 13,636,000,000
Pass-Through Certificates
Debt Instrument [Line Items]
Long term debt	$ 9,600,000,000
4.875% Senior Notes due 2025
Debt Instrument [Line Items]
Fixed interest rate	4.25%
Line of Credit \| Term Loan
Debt Instrument [Line Items]
Aggregate principal amount	$ 1,500,000,000
Quarterly principal repayment amount	0.25%
Line of Credit \| Term Loan \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Line of Credit \| Term Loan \| Alternative Rate Based on Certain Market Interest Rates
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement	$ 2,000,000,000.0
Available under revolving credit facility	$ 2,000,000,000.0
Commitment fee percentage	0.75%
Line of Credit \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Line of Credit \| Revolving Credit Facility \| Alternative Rate Based on Certain Market Interest Rates
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Secured Debt \| Borrowings Financing Aircraft Purchases
Debt Instrument [Line Items]
Aggregate principal amount	$ 105,000,000
Secured Debt \| Special Facility Revenue Bonds
Debt Instrument [Line Items]
Aggregate principal amount	$ 295,000,000
Fixed interest rate	4.00%
Mortgage \| Special Facility Revenue Bonds
Debt Instrument [Line Items]
Long term debt	$ 39,000,000
Senior Notes \| 4.875% Senior Notes due 2025
Debt Instrument [Line Items]
Aggregate principal amount		$ 350,000,000
Fixed interest rate		4.875%