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v3.21.2

Comprehensive Income (Loss) - Schedule of AOCI Components (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Mar. 31, 2021 | Sep. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | $ 9,688 | $ 8,876 | $ 8,876
Changes in fair value | 129 |  | 407
Reclassification to earnings | 2 |  | (16)
Balance at end of period | 10,250 | $ 9,093 | $ 10,250
Accounting Standards Update [Extensible Enumeration] |  | Accounting Standards Update 2016-01 | Accounting Standards Update 2016-01
Cumulative Effect, Period of Adoption, Adjustment |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period |  | $ 0 | $ 0
Accumulated other comprehensive income (loss) |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | 136 | (105) | (105)
Balance at end of period | 267 | (60) | 267
Accumulated other comprehensive income (loss) | Cumulative Effect, Period of Adoption, Adjustment |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period |  | (19) | (19)
Fuel and Interest Rate Derivatives | Fuel derivative contracts |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | 274 | (119) | (119)
Changes in fair value | 166 |  | 525
Reclassification to earnings | 2 |  | 36
Balance at end of period | 442 |  | 442
Fuel and Interest Rate Derivatives | Interest rate derivatives |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | (59) | (66) | (66)
Changes in fair value | 2 |  | 6
Reclassification to earnings | 1 |  | 4
Balance at end of period | (56) |  | (56)
Defined benefit plan items |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | (43) | (43) | (43)
Balance at end of period | (43) |  | (43)
Other |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period |  | 91 | 91
Reclassification to earnings |  |  | (60)
Balance at end of period | 0 |  | 0
Other | Cumulative Effect, Period of Adoption, Adjustment |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period |  | (31) | (31)
Deferred tax |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period | (36) | 32 | 32
Changes in fair value | (39) |  | (124)
Reclassification to earnings | (1) |  | 4
Balance at end of period | $ (76) |  | (76)
Deferred tax | Cumulative Effect, Period of Adoption, Adjustment |  |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |  |
Balance at beginning of period |  | $ 12 | $ 12

X
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