Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Assets [Abstract]
Derivatives	$ 68	$ 301
Total assets	68	301
Liabilities [Abstract]
Derivatives	121	98
Total liabilities	$ 121	$ 98

Fair value, before effects of master netting arrangements, of a financial liability or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Includes assets not subject to a master netting arrangement.

No definition available.

Name:	aexc_FairValueOfDerivativeLiabilities
Namespace Prefix:	aexc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant