Reduction in Effective Tax Rate

No definition available.

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- Definition

Tax years for which U.S. federal income tax audits were settled

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Provisional estimate or tax charges related to US tax legislation commonly referred to as the Tax Cuts and Jobs Act

+ References

No definition available.

+ Details

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Namespace Prefix:	aexc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

+ Details

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Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_IncomeTaxExaminationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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Income Taxes (Details Textuals) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
Income Taxes (Details Textuals) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Income Tax Examination [Line Items]
Actual tax rates	16.00%	(1.90%)	14.50%	(5.80%)
U.S. Tax Act discrete tax (benefit) charge				$ 24
Reduction in effective tax rate				7.80%
Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Open tax years by major tax jurisdiction			2016
Earliest Year [Member] \| Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Tax Audit Settlement Years					2008
Latest Year [Member] \| Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Tax Audit Settlement Years					2014