FAIR VALUE MEASUREMENTS - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Assets
Gross derivatives	$ 1,341	$ 1,374
Netting adjustment	(859)	(637)
Derivative asset	482	684
Liabilities
Gross derivatives	1,451	893
Netting adjustment	(862)	(639)
Net derivative liabilities	589	212
Recurring
Assets
Investment securities with a fair value	43,657	54,506
Netting adjustment	(859)	(691)
Derivative asset	482	684
Total assets	44,139	55,189
Liabilities
Netting adjustment	(862)	(681)
Net derivative liabilities	589	212
Other	627	863
Total liabilities	1,216	1,075
Recurring | Level 1
Assets
Investment securities with a fair value	6,754	11,434
Gross derivatives	0	0
Total assets	6,754	11,434
Liabilities
Gross derivatives	0	0
Other	0	0
Total liabilities	0	0
Recurring | Level 2
Assets
Investment securities with a fair value	30,483	35,849
Gross derivatives	1,340	1,357
Total assets	31,823	37,207
Liabilities
Gross derivatives	1,444	891
Other	627	863
Total liabilities	2,071	1,754
Recurring | Level 3
Assets
Investment securities with a fair value	6,421	7,222
Gross derivatives	1	17
Total assets	6,421	7,239
Liabilities
Gross derivatives	7	1
Other	0	0
Total liabilities	7	1
Recurring | Level 3 | U.S. corporate
Assets
Investment securities with a fair value	3,548	4,228
Recurring | Level 3 | Mortgage and asset-backed
Assets
Investment securities with a fair value	1,386	1,427
Recurring | Level 3 | Senior note | AerCap
Assets
Investment securities with a fair value	$ 900	$ 993