Concentration of Risk (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) country customer lease	Dec. 31, 2018 USD ($) aircraft country customer lease	Dec. 31, 2017 USD ($)
Concentration of risk
Number of aircraft leased \| lease	106	94
Number of countries \| country	59	56
Minimum percentage of aircraft operated internationally based on net book value	95.00%
Number of aircraft sold or agreed to be sold \| aircraft		6
Amount of Rental Revenue	$ 1,916,869	$ 1,631,200	$ 1,450,735
Aircraft Held For Sale
Concentration of risk
Number of aircraft sold or agreed to be sold \| aircraft		6
Flight Equipment, Net	$ 249,600	$ 241,600
Net book value of aircraft portfolio \| Geographic Region
Concentration of risk
Percent of Total	100.00%	100.00%
Net book value of aircraft portfolio \| Geographic Region \| Europe
Concentration of risk
Percent of Total	29.00%	29.90%
Net book value of aircraft portfolio \| Geographic Region \| Asia (excluding China)
Concentration of risk
Percent of Total	26.70%	24.50%
Net book value of aircraft portfolio \| Geographic Region \| China
Concentration of risk
Percent of Total	15.70%	17.00%
Net book value of aircraft portfolio \| Geographic Region \| The Middle East And Africa
Concentration of risk
Percent of Total	12.00%	12.40%
Net book value of aircraft portfolio \| Geographic Region \| Central America, South America And Mexico
Concentration of risk
Percent of Total	6.00%	6.90%
Net book value of aircraft portfolio \| Geographic Region \| U.S. and Canada
Concentration of risk
Percent of Total	5.30%	4.80%
Net book value of aircraft portfolio \| Geographic Region \| Pacific, Australia and New Zealand
Concentration of risk
Percent of Total	5.30%	4.50%
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others
Concentration of risk
Property, Plant and Equipment, Net	$ 18,704,337	$ 15,707,110
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| Europe
Concentration of risk
Property, Plant and Equipment, Net	5,438,775	4,692,341
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| Asia (excluding China)
Concentration of risk
Property, Plant and Equipment, Net	4,985,525	3,846,785
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| China
Concentration of risk
Property, Plant and Equipment, Net	2,930,752	2,663,903
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| The Middle East And Africa
Concentration of risk
Property, Plant and Equipment, Net	2,242,215	1,952,900
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| Central America, South America And Mexico
Concentration of risk
Property, Plant and Equipment, Net	1,116,814	1,078,900
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| U.S. and Canada
Concentration of risk
Property, Plant and Equipment, Net	996,398	757,884
Net book value of aircraft portfolio \| Geographic Region \| Assets Leased to Others \| Pacific, Australia and New Zealand
Concentration of risk
Property, Plant and Equipment, Net	$ 993,858	$ 714,397
Number of customers \| Geographic Region
Concentration of risk
Number of Customers \| customer	106	94
Percent of Total	100.00%	100.00%
Number of customers \| Geographic Region \| Europe
Concentration of risk
Number of Customers \| customer	43	33
Percent of Total	40.60%	35.10%
Number of customers \| Geographic Region \| Asia (excluding China)
Concentration of risk
Number of Customers \| customer	19	18
Percent of Total	17.90%	19.10%
Number of customers \| Geographic Region \| China
Concentration of risk
Number of Customers \| customer	9	9
Percent of Total	8.50%	9.60%
Number of customers \| Geographic Region \| The Middle East And Africa
Concentration of risk
Number of Customers \| customer	13	11
Percent of Total	12.30%	11.80%
Number of customers \| Geographic Region \| Central America, South America And Mexico
Concentration of risk
Number of Customers \| customer	9	10
Percent of Total	8.50%	10.60%
Number of customers \| Geographic Region \| U.S. and Canada
Concentration of risk
Number of Customers \| customer	10	10
Percent of Total	9.40%	10.60%
Number of customers \| Geographic Region \| Pacific, Australia and New Zealand
Concentration of risk
Number of Customers \| customer	3	3
Percent of Total	2.80%	3.20%
Flight equipment revenue \| Geographic Region
Concentration of risk
Amount of Rental Revenue	$ 1,916,869	$ 1,631,200	$ 1,450,735
Percent of Total	100.00%	100.00%	100.00%
Flight equipment revenue \| Geographic Region \| Europe
Concentration of risk
Amount of Rental Revenue	$ 531,778	$ 476,515	$ 450,628
Percent of Total	27.70%	29.20%	31.10%
Flight equipment revenue \| Geographic Region \| Asia (excluding China)
Concentration of risk
Amount of Rental Revenue	$ 484,017	$ 412,465	$ 332,284
Percent of Total	25.30%	25.30%	22.90%
Flight equipment revenue \| Geographic Region \| China
Concentration of risk
Amount of Rental Revenue	$ 357,278	$ 329,977	$ 324,147
Percent of Total	18.60%	20.20%	22.30%
Flight equipment revenue \| Geographic Region \| The Middle East And Africa
Concentration of risk
Amount of Rental Revenue	$ 226,932	$ 179,497	$ 116,799
Percent of Total	11.80%	11.00%	8.10%
Flight equipment revenue \| Geographic Region \| Central America, South America And Mexico
Concentration of risk
Amount of Rental Revenue	$ 124,850	$ 108,736	$ 102,205
Percent of Total	6.60%	6.70%	7.00%
Flight equipment revenue \| Geographic Region \| U.S. and Canada
Concentration of risk
Amount of Rental Revenue	$ 98,627	$ 77,678	$ 76,685
Percent of Total	5.10%	4.80%	5.30%
Flight equipment revenue \| Geographic Region \| Pacific, Australia and New Zealand
Concentration of risk
Amount of Rental Revenue	$ 93,387	$ 46,332	$ 47,987
Percent of Total	4.90%	2.80%	3.30%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The net amount of long-lived, depreciable flight assets used in the entity's principle business operations, including owned aircraft and on capital lease, as well as capitalized improvements.

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The number of countries in which the entity operates as of balance sheet date.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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The number of aircraft sold by the entity during the period.

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