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Equipment Held for Operating Lease (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($) aircraft item region | Dec. 31, 2016 USD ($) aircraft item | Dec. 31, 2015 USD ($)
Equipment Held for Lease |  |  |
Number of geographic regions in which aircraft lessees are domiciled in | region | 8 |  |
Lease rent revenue | $ 130,369 | $ 119,895 | $ 108,046
Net book value of equipment held for operating lease | 1,342,571 | 1,136,603 |
Minimum future payments under non-cancelable leases |  |  |
2018 | 110,666 |  |
2019 | 54,245 |  |
2020 | 31,913 |  |
2021 | 16,757 |  |
2022 | 10,652 |  |
Thereafter | 13,242 |  |
Minimum future payments | 237,475 |  |
Europe |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 50,789 | 44,650 | 43,703
Net book value of equipment held for operating lease | 444,938 | 384,661 |
Asia |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 34,169 | 34,524 | 31,569
Net book value of equipment held for operating lease | 258,501 | 265,736 |
South America |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 11,958 | 11,504 | 9,688
Net book value of equipment held for operating lease | 111,999 | 112,268 |
United States |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 20,307 | 13,395 | 9,177
Net book value of equipment held for operating lease | 251,959 | 148,208 |
Mexico |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 5,409 | 6,251 | 6,886
Net book value of equipment held for operating lease | 34,399 | 55,114 |
Canada |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 4,355 | 4,049 | 2,828
Net book value of equipment held for operating lease | 28,977 | 35,199 |
Middle East |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 3,360 | 3,674 | 2,223
Net book value of equipment held for operating lease | 61,606 | 8,971 |
Africa |  |  |
Equipment Held for Lease |  |  |
Lease rent revenue | 22 | 1,848 | $ 1,972
Net book value of equipment held for operating lease | 2,959 | 42,949 |
Off-lease and other |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | $ 147,233 | $ 83,497 |
Equipment held for lease Member | Engines and related equipment |  |  |
Equipment Held for Lease |  |  |
Number of equipments held for lease | aircraft | 225 | 208 |
Equipment held for lease Member | Other leased parts and equipment |  |  |
Equipment Held for Lease |  |  |
Number of equipments held for lease | item | 7 | 5 |
Equipment held for lease Member | Aircrafts |  |  |
Equipment Held for Lease |  |  |
Number of equipments held for lease | aircraft | 16 | 11 |
Month-to-month leases |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | $ 89,795 |  |
Leases expiring 2018 |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | 528,225 |  |
Leases expiring 2019 |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | 236,080 |  |
Leases expiring 2020 |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | 158,264 |  |
Leases expiring 2021 |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | 57,268 |  |
Leases expiring 2022 |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | 33,181 |  |
Leases expiring thereafter |  |  |
Equipment Held for Lease |  |  |
Net book value of equipment held for operating lease | $ 92,525 |  |

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- Definition Future minimum rental payments in aggregate as of the balance sheet date under operating leases. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718 + Details
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- Definition The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39896-112707 + Details
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