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Organization and Summary of Significant Accounting Policies (Fair Value on a Nonrecurring Basis) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Assets at fair value and gains (losses) recorded |  |  |
Derivative, Notional Amount | $ 100,000,000 |  |
Derivatives |  | $ 0 |
Equipment held for sale | 30,710,000 | 23,454,000 |
Assets at fair value | 69,000 |  |
Increase (decrease) in asset write-down | 25,000 |  |
Asset write-down | 9,514,000 | 9,181,000 | $ 5,602,000
Additional write-down |  | 2,800,000 |
Asset helf-for-use write-down |  | 300,000 |
Equipment |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset helf-for-use write-down |  | 600,000 |
Engine Parts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down | 2,000,000 |  |
Additional write-down | 2,000,000 |  |
Recurring | Level 1 |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Derivatives | 69,000 |  |
Total | 69,000 |  |
Recurring | Level 3 |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Derivatives | 69,000 |  |
Total | 69,000 |  |
Nonrecurring |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | 1,196,000 | 2,154,000 |
Equipment held for sale | 8,976,000 | 4,931,000 |
Spare parts inventory | 1,538,000 |  |
Assets at fair value | 11,710,000 | 7,085,000 |
Total losses on equipment held for lease | (3,674,000) | (2,536,000) |
Total losses on equipment held for sale | (5,365,000) | (6,645,000) |
Total losses on spare parts inventory | (475,000) |  |
Total losses on assets | (9,514,000) | (9,181,000) |
Nonrecurring | Equipment |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down recorded earlier | 5,500,000 |  |
Nonrecurring | Level 2 |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | 1,196,000 | 2,154,000 |
Equipment held for sale | 8,976,000 | 4,931,000 |
Spare parts inventory | 1,538,000 |  |
Assets at fair value | 11,710,000 | $ 7,085,000 |
Engines and related equipment | Nonrecurring |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down | $ 9,500,000 |  |

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