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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Face (par) amount of debt instrument at time of issuance.

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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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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 after the fifth 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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Debt (AerCap trust & AICDC notes) (Details) - USD ($)	12 Months Ended
Debt (AerCap trust & AICDC notes) (Details) - USD ($)	Dec. 31, 2018	Jan. 31, 2019	Dec. 31, 2017
Maturities of Long-term Debt [Abstract]
2019	$ 4,108,660,000
2020	4,008,209,000
2021	3,783,405,000
2022	7,246,201,000
2023	3,414,995,000
Thereafter	6,931,611,000
Unsecured
Maturities of Long-term Debt [Abstract]
Debt	17,187,314,000		$ 15,206,290,000
Unsecured \| AerCap Trust & AICDC Notes
Maturities of Long-term Debt [Abstract]
2019	1,099,864,000
2020	1,500,000,000
2021	1,900,000,000
2022	2,100,000,000
2023	1,200,000,000
Thereafter	2,950,000,000
Debt	$ 10,749,864,000		$ 8,399,864,000
Redemption price of debt instrument, percentage	100.00%
Unsecured \| AerCap Trust & AICDC Notes \| Minimum
Maturities of Long-term Debt [Abstract]
Stated interest rate	3.30%
Unsecured \| AerCap Trust & AICDC Notes \| Maximum
Maturities of Long-term Debt [Abstract]
Stated interest rate	5.00%
Subsequent Event \| Unsecured \| Senior Notes, 4.45% Due 2021
Maturities of Long-term Debt [Abstract]
Stated interest rate		4.45%
Face amount		$ 700,000,000
Subsequent Event \| Unsecured \| Senior Notes, 4.875% Due 2024
Maturities of Long-term Debt [Abstract]
Stated interest rate		4.875%
Face amount		$ 400,000,000