Consolidated Statement of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Deferred taxes on postretirement	$ 25	$ (15)	$ (9)
Deferred taxes on unrealized gain (loss), other, tax effect	(13)	7	8
Fuel derivative contracts
Deferred taxes on unrealized gain (loss) on derivatives, tax effect	142	2	(16)
Interest rate derivatives
Deferred taxes on unrealized gain (loss) on derivatives, tax effect	$ 2	$ (8)	$ (8)

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=123454820&loc=SL4569616-111683

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