Debt (AerCap trust & AICDC notes) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Maturities of Long-term Debt [Abstract]
2022	$ 3,982,938
2023	7,329,640
2024	8,910,800
2025	6,130,155
2026	5,939,562
Thereafter	18,249,021
Unsecured
Maturities of Long-term Debt [Abstract]
Debt	37,079,686	$ 15,776,730
Unsecured \| AerCap Trust & AICDC Notes
Maturities of Long-term Debt [Abstract]
2022	867,202
2023	4,700,000
2024	6,800,000
2025	3,650,000
2026	5,250,000
Thereafter	12,900,000
Debt	$ 34,167,202	$ 12,797,126
Redemption price of debt instrument, percentage	100.00%
Unsecured \| AerCap Trust & AICDC Notes \| Minimum
Maturities of Long-term Debt [Abstract]
Stated interest rate	0.68%
Unsecured \| AerCap Trust & AICDC Notes \| Maximum
Maturities of Long-term Debt [Abstract]
Stated interest rate	6.50%

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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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 requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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