CARES Act, Class of Warrant or Right, Expected

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- Definition

CARES Act Loan, Remaining Outstanding, Amount

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No definition available.

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- Definition

CARES Act, Payroll Support Program, Grant

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- Definition

CARES Act, Payroll Support Program, Grant, Carrying Value, Total

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- Definition

CARES Act, Payroll Support Program, Total Payment

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- Definition

CARES Act, Secured Loans, Eligibility Amount

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- Definition

Debt Instrument, Amortization Payments, Percentage

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- Definition

Debt Instrument Covenant Collateral Coverage Ratio Minimum

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- Definition

Number of Aircraft, Secured Debt Transactions

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of flight equipment which are owned but transferred to serve as collateral for the payment of the related debt obligation, primarily a secured borrowing or repurchase agreement, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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No definition available.

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- Definition

Proceeds from Sale Leaseback Transactions

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Sale Leaseback, Cash Proceeds, Financing

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Sale Leaseback, Cash Proceeds, Investing

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of warrants or rights outstanding.

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- Definition

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

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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

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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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

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- Definition

Amount of the fees associated with providing collateral for the credit facility.

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

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The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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- Definition

Amount of cash outflow for short-term and long-term debt and lease obligation.

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Amount of gain (loss) on sale and leaseback transaction from transfer of asset accounted for as sale.

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- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Long-term Debt, Short-term Borrowings and Finance Lease Obligations - Narrative (Details) $ / shares in Units, shares in Millions					1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 29, 2021 USD ($) $ / shares shares	Jan. 15, 2021 $ / shares shares	Sep. 29, 2020 USD ($) $ / shares shares	Apr. 23, 2020 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) trading_day $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($)	Nov. 03, 2020 USD ($)	Sep. 30, 2020	Aug. 31, 2020 USD ($) airbus	Jun. 17, 2020 USD ($)
Line of Credit Facility [Line Items]
Reduction in outstanding debt and capital lease obligations						$ 644,000,000
Pledged assets not separately reported flight equipment					$ 6,800,000,000	6,800,000,000
CARES act, payroll support program, total payment				$ 963,000,000		504,000,000
CARES act, payroll support program, grant				$ 704,000,000		383,000,000
Class of warrant or right, outstanding (in shares) \| shares		0.8	1.2	2.7
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares		$ 14.43	$ 9.50	$ 9.50
Warrants and rights outstanding, term		5 years		5 years
Warrants and rights outstanding					8,000,000	8,000,000
CARES act, payroll support program, grant, carrying value, total					$ 375,000,000	$ 375,000,000
CARES act, secured loans, eligibility amount								$ 1,900,000,000
CARES act, class of warrant or right, expected (in shares) \| shares					20.5	20.5
Line of credit facility, remaining borrowing capacity								$ 1,100,000,000
CARES act loan remaining outstanding amount					$ 115,000,000	$ 115,000,000
Proceeds from sale leaseback transactions							$ 563,000,000
Proceeds from sale-leaseback transactions							354,000,000
Proceeds from sale-leaseback transactions							209,000,000
Sale and leaseback transaction, gain (loss), net							$ 106,000,000
Subsequent Event
Line of Credit Facility [Line Items]
CARES act, payroll support program, total payment	$ 76,000,000
CARES act, payroll support program, grant	$ 53,000,000
Class of warrant or right, outstanding (in shares) \| shares	0.2
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 14.43
Unsecured Debt
Line of Credit Facility [Line Items]
CARES act, payroll support program, grant						87,000,000
Warrants and rights outstanding					19,000,000	19,000,000
CARES act, payroll support program, grant, carrying value, total					685,000,000	685,000,000
Convertible Senior Notes Due 2026 \| Senior Notes
Line of Credit Facility [Line Items]
Debt instrument, face amount					$ 750,000,000	$ 750,000,000
Debt instrument, interest rate, stated percentage					0.50%	0.50%
Proceeds from offering					$ 734,000,000
Debt Instrument, Convertible, Conversion Ratio					0.0385802
Debt instrument, convertible, conversion price (in dollars per share) \| $ / shares					$ 25.92	$ 25.92
Trading days \| trading_day					20
Convertible Senior Notes Due 2026 \| Senior Notes \| Debt Instrument, Redemption, Period One
Line of Credit Facility [Line Items]
Debt instrument, redemption price, percentage					100.00%
Convertible Senior Notes Due 2026 \| Senior Notes \| Debt Instrument, Redemption, Period Two
Line of Credit Facility [Line Items]
Debt instrument, redemption price, percentage					130.00%
Fixed rate enhanced equipment notes, 2020-1A and B \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount										$ 808,000,000
Fixed rate enhanced equipment notes, 2020-1A and B \| Long-term Debt \| Airbus A321
Line of Credit Facility [Line Items]
Secured debt \| airbus										24
2020-1 Series A, due through 2032 \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount										$ 636,000,000
Debt instrument, interest rate, stated percentage										4.00%
2020-1 Series B, due through 2028 \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount										$ 172,000,000
Debt instrument, interest rate, stated percentage										7.75%
2019-1 Series B, due through 2027 \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount										$ 115,000,000
Debt instrument, interest rate, stated percentage										8.00%
2019-1 Series B, due through 2027 \| Long-term Debt \| Airbus A321
Line of Credit Facility [Line Items]
Secured debt \| airbus										25
US Department of Treasury \| Unsecured Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount				$ 259,000,000	$ 121,000,000	$ 121,000,000
Debt instrument, interest rate, stated percentage		1.00%		1.00%
Long-term debt, term				10 years
US Department of Treasury \| Unsecured Debt \| Subsequent Event
Line of Credit Facility [Line Items]
Debt instrument, face amount	$ 23,000,000
US Department of Treasury \| Unsecured Debt \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Line of Credit Facility [Line Items]
Debt instrument, term		10 years
Debt instrument, basis spread on variable rate		2.00%		2.00%
US Department of Treasury \| Secured CARES Act Loan, due through 2025 \| Long-term Debt
Line of Credit Facility [Line Items]
Line of credit facility, collateral fees, amount						$ 550,000,000
Barclays \| Floating rate term loan credit facility, due through 2024 \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount											$ 750,000,000
Debt instrument, interest rate, stated percentage					6.25%	6.25%
Amortization payments, percentage									5.00%
US Department of Treasury \| Secured CARES Act Loan, due through 2025 \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, face amount			$ 115,000,000
Debt instrument covenant collateral coverage ratio minimum			1.6
Line of credit facility, maximum borrowing capacity			$ 1,100,000,000
US Department of Treasury \| Secured CARES Act Loan, due through 2025 \| Long-term Debt \| Maximum
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			1.00%
US Department of Treasury \| Secured CARES Act Loan, due through 2025 \| Long-term Debt \| Minimum
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.00%
US Department of Treasury \| Secured CARES Act Loan, due through 2025 \| London Interbank Offered Rate (LIBOR) \| Long-term Debt
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			2.75%
Citibank \| Citibank line of credit, due through 2023 \| Line of Credit
Line of Credit Facility [Line Items]
Line of credit, current					$ 550,000,000	$ 550,000,000
Morgan Stanley \| Line of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity					$ 200,000,000	$ 200,000,000