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

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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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.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Number of Engines

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