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Financial Derivative Instruments Narrative (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) aircraft | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Derivative [Line Items] |  |  |
Discontinuation of Interest Rate Cash Flow Hedge Balance in AOCI | $ 62 |  |
Current Unrealized Net Losses in OCI | 19 |  |
Maximum sum of derivatives of counterparty to be included in other | $ 4 |  |
Cash Collateral Percent Of Fair Value Fuel Derivatives Contracts | 100.00% |  |
Letter of Credit Percent of Collateral | 100.00% |  |
Interest Rate Swap Derivative, Aircraft Leases Received in December 2020 | aircraft | 3 |  |
Interest Rate Swap Derivative, Aircraft Leases Received in First Quarter 2021 | 8 |  |
Fuel derivatives |  |  |
Derivative [Line Items] |  |  |
Cash collateral held (from) by CP | $ 72 |  |
Fuel derivatives | Cash Flow Hedging | Operating Expense [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative Instruments, (Gain) Loss Reclassified from Accumulated OCI into Income, Effective Portion, Net | $ 0 |  |
Interest rate swap |  |  |
Derivative [Line Items] |  |  |
Interest Rate Derivative | 12 |  |
Interest rate derivatives |  |  |
Derivative [Line Items] |  |  |
Cash collateral held (from) by CP | $ 0 |  |
Interest rate derivatives | Cash Flow Hedging | Operating Expense [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative Instruments, (Gain) Loss Reclassified from Accumulated OCI into Income, Effective Portion, Net | 1 | $ 0 |
Other Noncurrent Liabilities | Interest rate derivatives |  |  |
Derivative [Line Items] |  |  |
Derivative contracts | $ 0 |  | $ 6

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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624258-113959 + Details
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- Definition Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121590274&loc=d3e41678-113959 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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