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Fair Value Measurements -Nonrecurring Basis (Details) | 12 Months Ended
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Dec. 31, 2017 USD ($) engine aircraft | Dec. 31, 2016 USD ($) engine aircraft | Dec. 31, 2015 USD ($)
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for sale | $ 34,172,000 | $ 30,710,000 |
Assets at fair value | 1,100,000 | $ 68,000 |
Number of engines | engine |  | 393 |
Asset write-down | $ 24,930,000 | $ 9,514,000 | $ 9,181,000
Equipment |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down |  | $ 2,000,000 |
Engine Parts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of engines | engine | 9 | 6 |
Number of engines for which impairment is recorded earlier due to part out and sale | engine |  | 1 |
Additional write-down |  | $ 2,000,000 |
Engine and aircraft |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Additional write down to reflect the estimated market value |  | $ 5,500,000 |
Aircrafts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of aircraft | aircraft | 5 | 1 |
Asset write-down | $ 4,700,000 |  |
Nonrecurring |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | 23,255,000 | $ 1,196,000 |
Equipment held for sale | 39,261,000 | 8,976,000 |
Spare parts inventory | 5,336,000 | 1,538,000 |
Assets at fair value | 67,852,000 | 11,710,000 |
Total losses on equipment held for lease | (12,879,000) | (3,674,000) |
Total losses on equipment held for sale | (8,708,000) | (5,365,000) |
Total losses on spare parts inventory | (3,343,000) | (475,000) |
Total losses on assets | (24,930,000) | (9,514,000) |
Nonrecurring | Engine Parts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down | 16,900,000 |  |
Nonrecurring | Level 2 |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | 23,255,000 | 1,196,000 |
Equipment held for sale | 39,261,000 | 8,976,000 |
Spare parts inventory | 5,336,000 | 1,538,000 |
Assets at fair value | $ 67,852,000 | $ 11,710,000 |
Engines and related equipment |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of engines | engine | 48 |  |

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- Definition This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References No definition available. + Details
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- Definition Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value. + References No definition available. + Details
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- Definition Nonrecurring impairment charges related to the write-off of production-related equipment and inventory. This tag is used when an Entity charges this cost to cost of goods sold. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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- Definition The amount of additional production related impairments or charges to reflect the estimated market value. + References No definition available. + Details
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