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Organization and Summary of Significant Accounting Policies - Equipment Held of Operating Lease (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) engine | Dec. 31, 2019 USD ($)
Equipment Held for Operating Lease |  |
Accumulated depreciation | $ (11,356) | $ (8,666)
Engines and related equipment | 31,753 | 31,520
Write-down of equipment | $ 20,540 | 18,220
Minimum |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 3 years |
Maximum |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 37 years |
Equipment held for lease |  |
Equipment Held for Operating Lease |  |
Gross value | $ 2,340,736 | 2,065,753
Accumulated depreciation | (454,123) | (414,835)
Engines and related equipment | 1,886,613 | 1,650,918
Write-down of equipment | $ 4,900 | 6,400
Equipment held for lease | Engines and related equipment |  |
Equipment Held for Operating Lease |  |
Residual value, percent | 55.00% |
Estimated useful life | 15 years |
Gross value | $ 2,238,160 | 1,920,215
Accumulated depreciation | (445,780) | (401,776)
Engines and related equipment | 1,792,380 | 1,518,439
Equipment held for lease | Aircraft and airframes |  |
Equipment Held for Operating Lease |  |
Gross value | 89,613 | 133,424
Accumulated depreciation | (7,312) | (12,630)
Engines and related equipment | $ 82,301 | 120,794
Equipment held for lease | Spare part packages |  |
Equipment Held for Operating Lease |  |
Residual value, percent | 25.00% |
Equipment held for lease | Marine Vessel |  |
Equipment Held for Operating Lease |  |
Residual value, percent | 15.00% |
Estimated useful life | 18 years |
Gross value | $ 12,963 | 12,114
Accumulated depreciation | (1,031) | (429)
Engines and related equipment | 11,932 | $ 11,685
Equipment held for lease | Older generation engines |  |
Equipment Held for Operating Lease |  |
Gross value | $ 51,600 |
Number of engines | engine | 50 |
Equipment held for lease | Minimum | Aircraft and airframes |  |
Equipment Held for Operating Lease |  |
Residual value, percent | 15.00% |
Estimated useful life | 13 years |
Equipment held for lease | Minimum | Spare part packages |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 14 years |
Equipment held for lease | Minimum | Older generation engines |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 1 month |
Equipment held for lease | Maximum | New engine |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 25 years |
Equipment held for lease | Maximum | Aircraft and airframes |  |
Equipment Held for Operating Lease |  |
Residual value, percent | 17.00% |
Estimated useful life | 20 years |
Equipment held for lease | Maximum | Spare part packages |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 15 years |
Equipment held for lease | Maximum | Older generation engines |  |
Equipment Held for Operating Lease |  |
Estimated useful life | 125 months |

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