Special Items (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Property, Plant and Equipment [Line Items]
Special Items - CARES Act Payroll Support	$ (304,000,000)		$ 0	$ (304,000,000)	$ 0
Special Items - Fleet Impairment	0	$ 202,000,000	0	202,000,000	0
Special Items - E190 Fleet Transition	0		0	0	9,000,000
Special Items - Union Contract Costs	0		2,000,000	0	5,000,000
Special Items	$ (304,000,000)		$ 2,000,000	(102,000,000)	14,000,000
Impairment of Long-Lived Assets Held-for-use				$ 202,000,000	$ 0

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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