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AOCI - Schedule of AOCI Components (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2019
Fuel derivatives |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | $ (31) | $ (56)
Changes in fair value | (123) | (107)
Ending Balance | (135) | (135)
Interest rate derivatives |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | (33) | 0
Changes in fair value | (22) | (56)
Reclassification to earnings | 2 | 3
Ending Balance | (53) | (53)
Defined Benefit Plan Items |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | 58 | 58
Changes in fair value | 0 | 0
Reclassification to earnings | 0 | 0
Ending Balance | 58 | 58
Other comprehensive income other changes net of tax |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | 45 | 25
Changes in fair value | 2 | 22
Reclassification to earnings | 0 | 0
Ending Balance | 47 | 47
Deferred Tax |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | (9) | (7)
Changes in fair value | 33 | 33
Reclassification to earnings | (4) | (6)
Ending Balance | 20 | 20
AOCI Including Portion Attributable to Noncontrolling Interest |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Beginning Balance | 30 | 20
Changes in fair value | (110) | (108)
Reclassification to earnings | 17 | 25
Ending Balance | (63) | (63)
Reclassification out of Accumulated Other Comprehensive Income | Fuel derivatives |  |
AOCI Attributable to Parent, Net of Tax [Roll Forward] |  |
Reclassification to earnings | $ (19) | $ (28)

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