Asset Securitizations (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Assets from Trusts [Line Items]
Restricted cash and cash equivalents	$ 526	$ 514
American Express Lending Trust
Assets from Trusts [Line Items]
Direct and Indirect ownership of variable interests	14,100	15,300
Restricted cash and cash equivalents	68	66
American Express Charge Trust
Assets from Trusts [Line Items]
Direct and Indirect ownership of variable interests	4,900	4,600
Restricted cash and cash equivalents	$ 0	$ 0