Line of Credit Facility, Number of Lines Drawn in Current Period

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- Definition

Unsecured Term Loan through PSP of CARES Act

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Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants.

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- Definition

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

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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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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No definition available.

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Discussion of whether the debt instrument is secured or unsecured, and, if secured, a description of the collateral and guarantees required or provided.

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- Definition

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

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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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No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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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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- Definition

Maximum month-end amount borrowed under the credit facility during the period.

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- Definition

Amount of the required periodic payment applied to principal.

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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.

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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

+ References

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The entire disclosure for long-term debt.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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- Definition

The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt.

+ References

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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- Definition

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

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LONG-TERM DEBT - SCHEDULE OF LONG-TERM DEBT (Details)		3 Months Ended		9 Months Ended		60 Months Ended
LONG-TERM DEBT - SCHEDULE OF LONG-TERM DEBT (Details)	Oct. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2020 USD ($) credit_facility	Sep. 30, 2019 USD ($)	Apr. 22, 2030	Sep. 28, 2020 shares	Sep. 01, 2020 USD ($)	Apr. 23, 2020 $ / shares	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Debt Issuance Costs, Net		$ (35,000,000)		$ (35,000,000)						$ (8,000,000)
Total		$ 3,822,000,000		$ 3,822,000,000						$ 1,499,000,000
Weighted-average fixed-interest rate		4.30%		4.30%						3.30%
Weighted-average variable-interest rate		1.90%		1.90%						2.90%
Long-term debt payments				$ 238,000,000	$ 129,000,000
Proceeds from Lines of Credit				$ 400,000,000
Line of Credit Facility, Number Drawn in Current Period \| credit_facility				2
Long-term Debt and Lease Obligation, Current		$ 1,150,000,000		$ 1,150,000,000						$ 235,000,000
Long-term Debt and Lease Obligation		2,672,000,000		2,672,000,000						1,264,000,000
Unsecured Term Loan through PSP of CARES Act		290,000,000		290,000,000						0
Proceeds from issuance of debt				$ 2,581,000,000	$ 356,000,000
Adjustments to Additional Paid in Capital, Warrant Issued		9,000,000	$ 7,000,000
LONG-TERM DEBT				2024
Line of Credit Facility, Maximum Borrowing Capacity		461,000,000		$ 461,000,000
Adjustments to Additional Paid in Capital, Warrant Issued		9,000,000	$ 7,000,000
ALK Common Stock Warrant [Member]
Debt Instrument [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights \| $ / shares									$ 31.61
Aircraft Type [Domain]
Debt Instrument [Line Items]
Debt Instrument, Collateral				32
Fixed rate notes payable due through 2029 [Member]
Debt Instrument [Line Items]
Total		427,000,000		$ 427,000,000						475,000,000
Variable rate notes payable due through 2029 [Member] [Member]
Debt Instrument [Line Items]
Total		1,966,000,000		1,966,000,000						1,032,000,000
Proceeds from Issuance of Long-term Debt				589,000,000
Proceeds from Issuance of Long-term Debt				589,000,000
CARES Act Unsecured Interest Rate Years 1 to 5 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage									1.00%
Debt Instrument, Basis Spread on Variable Rate						2.00%
Debt Instrument, Interest Rate, Stated Percentage									1.00%
Debt Instrument, Basis Spread on Variable Rate						2.00%
Credit Facility 3 [Member] \| Secured by certain accounts receivable, spare engines, spare parts and ground service equipment [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		120,000,000		120,000,000				$ 150,000,000
July 2020 EETC
Debt Instrument [Line Items]
Total		1,174,000,000		1,174,000,000						$ 0
US Treasury CARES Act Loan [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit				135,000,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights \| shares							427,080
Adjustments to Additional Paid in Capital, Warrant Issued				6,000,000
Line of Credit Facility, Maximum Borrowing Capacity		1,300,000,000		1,300,000,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights \| shares							427,080
Adjustments to Additional Paid in Capital, Warrant Issued				6,000,000
US Treasury CARES Act Loan [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,900,000,000
US Treasury CARES Act Loan [Member] \| Aircraft Type [Domain] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral	34
US Treasury CARES Act Loan [Member] \| 3724 Aircraft Engines and Engine Parts [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt Instrument, Collateral	15
Credit Facilities 1 & 2 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Month-end Outstanding Amount				363,000,000
Line of Credit Facility, Periodic Payment, Principal				37,000,000
Line of Credit Facility, Maximum Month-end Outstanding Amount				363,000,000
Line of Credit Facility, Periodic Payment, Principal				37,000,000
Variable Rate debt with interest rate swap [Member]
Debt Instrument [Line Items]
Total		$ 642,000,000		$ 642,000,000