Commitments (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) airbus aircraft
Unrecorded Unconditional Purchase Obligation [Line Items]
2021	$ 1,000
2022	700
2023	1,500
2024	1,800
2025	1,200
Thereafter	1,600
Other Commitments [Abstract]
Restricted assets pledged related to workers compensation insurance policies and other business partner agreements	$ 23
Percentage of employees represented by unions under collective bargaining agreements	51.00%
Employment agreement	five years
Employment agreement automatic renewal term	five years
Renewal notice period	90 days
A-321 Neo
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of aircraft and spare engine orders by the firm \| airbus	72
Number of aircraft scheduled to receive next year \| aircraft	8
A220-300
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of aircraft and spare engine orders by the firm \| airbus	69
Number of aircraft scheduled to receive next year \| aircraft	7

Commitments.

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Employment Agreement Automatic Renewal Term

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Term of employment agreement for FAA-licensed employees.

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Number Of Aircraft Scheduled To Receive Next Year

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Percentage Of Employees Represented By Unions Under Collective Bargaining Agreements

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Renewal notice period for employment agreements of FAA-licensed employees.

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Restricted assets pledged under standby letters of credit related to workers compensation insurance policies and other agreements requiring issuance of letters of credit.

+ References

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- Definition

Unrecorded Unconditional Purchase Obligations Disclosure.

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of fixed and determinable portion of unrecorded unconditional purchase obligation to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308

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