Commitments and contingencies (Unrecorded contractual commitments for purchase of flight equipment) (Details) - Capital Addition Purchase Commitments $ in Thousands	1 Months Ended	12 Months Ended
Feb. 29, 2020 aircraft	Dec. 31, 2019 USD ($) aircraft
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of forward orders \| aircraft		299
Flight Equipment
Unrecorded Unconditional Purchase Obligation [Line Items]
2020		$ 3,470,502
2021		4,351,839
2022		2,992,145
2023		2,651,197
2024		1,807,081
Thereafter		1,270,782
Total		$ 16,543,546
Number of forward orders \| aircraft		297
Number of purchase-leaseback transactions \| aircraft		2
Airbus 320 neoFamily Aircraft \| Subsequent Event \| Flight Equipment
Unrecorded Unconditional Purchase Obligation [Line Items]
Number of forward orders \| aircraft	50

Number Of Forward Orders

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- Definition

Number Of Purchase And Leaseback Transactions

+ References

No definition available.

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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