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Commitments and Contingengies - Long-term Purchase Commitments (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) aircraft
Aircraft [Member] |
Long-term Purchase Commitment [Line Items] |
Committed expenditures, 2018 | $ | $ 874
Committed expenditures, 2019 | $ | 666
Committed expenditures, 2020 | $ | 1,100
Committed expenditures, 2021 | $ | 1,300
Committed expenditures, 2022 | $ | 877
Committed expenditures, 2023 and beyond | $ | $ 5,200
B-737-Max [Member] |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | 13
B-737-800 |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | 39
Long-term Purchase Commitment, Minimum Quantity Required | 26
B-737-700 |
Long-term Purchase Commitment [Line Items] |
Property, Plant and Equipment, Number of Aircraft Purchased | 18
B-737-8 Max |
Long-term Purchase Commitment [Line Items] |
Long-term Purchase Commitment, Minimum Quantity Required | 197
Options - 737MAX (in units) | 155
B-737-7 Max |
Long-term Purchase Commitment [Line Items] |
Long-term Purchase Commitment, Minimum Quantity Required | 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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -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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