Debt (ILFC) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Maturities of Long-term Debt [Abstract]
2019	$ 4,108,660
2020	4,008,209
2021	3,783,405
2022	7,246,201
Unsecured
Maturities of Long-term Debt [Abstract]
Debt	17,187,314	$ 15,206,290
Unsecured \| ILFC Legacy Notes
Maturities of Long-term Debt [Abstract]
2019	2,000,000
2020	1,000,000
2021	500,000
2022	1,400,000
Debt	$ 4,900,000	$ 5,670,000
Minimum \| Unsecured \| ILFC Legacy Notes
Maturities of Long-term Debt [Abstract]
Stated interest rate	4.625%
Maximum \| Unsecured \| ILFC Legacy Notes
Maturities of Long-term Debt [Abstract]
Stated interest rate	8.625%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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