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Commitments and Contingengies - Long-term Purchase Commitments (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) aircraft
Aircraft |
Long-term Purchase Commitment [Line Items] |
Committed expenditures, 2019 | $ | $ 924
Committed expenditures, 2020 | $ | 1,379
Committed expenditures, 2021 | $ | 1,663
Committed expenditures, 2022 | $ | 1,202
Committed expenditures, 2023 | $ | 1,596
Committed expenditures, 2024 and beyond | $ | $ 3,444
B-737-8 Max |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | aircraft | 18
B-737-800 |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | aircraft | 26
B-737-700 |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | aircraft | 1
B-737-8 Max |
Long-term Purchase Commitment [Line Items] |
Long-term Purchase Commitment, Minimum Quantity Required | aircraft | 219
Options - 737MAX (in units) | aircraft | 115
B-737-7 Max |
Long-term Purchase Commitment [Line Items] |
Options - 737MAX (in units) | aircraft | 30

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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 + Details
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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 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 + Details
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