The ratio of Allowance for Credit Losses to All Loans.

No definition available.

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Period Type:	instant

- Definition

Amount of gain (loss) from converting allowance reserve for credit loss to currency of reporting entity from amount denominated or measured in a different currency, which decreases (increases) the allowance for loan and lease losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Period Type:	duration

- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-SubTopic 220
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Credit Quality And Allowance For Credit Losses (Changes In The Allowance For Loan Losses And Related Loan Amounts) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses	$ 0	$ 24	$ (17)	$ 57
Total loans					$ 49,010	$ 49,173
Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	677	705	712	730
Loan charge-offs	(25)	(37)	(82)	(120)
Recoveries on loans previously charged-off	10	12	42	44
Net loan recoveries (charge-offs)	(15)	(25)	(40)	(76)
Provision for loan losses	1	31	(8)	57
Foreign currency translation adjustment	1	1	0	1
Balance at end of period	664	712	664	712
As a percentage of total loans					1.35%		1.45%
Allowance for loan losses individually evaluated for impairment					$ 29		$ 90
Allowance for loan losses collectively evaluated for impairment					635		622
Total allowance for loan losses	677	705	712	730	664	712	712
Loans individually evaluated for impairment					303		538
Loans collectively evaluated for impairment					48,707		48,671
Total loans					$ 49,010		$ 49,209
Business loans \| Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	635	661	661	682
Loan charge-offs	(24)	(36)	(78)	(115)
Recoveries on loans previously charged-off	9	10	39	39
Net loan recoveries (charge-offs)	(15)	(26)	(39)	(76)
Provision for loan losses	(1)	21	(2)	50
Foreign currency translation adjustment	1	1	0	1
Balance at end of period	620	657	620	657
As a percentage of total loans					1.39%		1.47%
Allowance for loan losses individually evaluated for impairment					$ 29		$ 90
Allowance for loan losses collectively evaluated for impairment					591		567
Total allowance for loan losses	635	661	661	682	620	661	657
Loans individually evaluated for impairment					269		501
Loans collectively evaluated for impairment					44,358		44,198
Total loans					44,627		$ 44,699
Retail loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Total loans					$ 4,383	4,542
Retail loans \| Financing Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	42	44	51	48
Loan charge-offs	(1)	(1)	(4)	(5)
Recoveries on loans previously charged-off	1	2	3	5
Net loan recoveries (charge-offs)	0	1	(1)	0
Provision for loan losses	2	10	(6)	7
Foreign currency translation adjustment	0	0	0	0
Balance at end of period	44	55	44	55
As a percentage of total loans					1.00%		1.23%
Allowance for loan losses individually evaluated for impairment					$ 0		$ 0
Allowance for loan losses collectively evaluated for impairment					44		55
Total allowance for loan losses	$ 42	$ 44	$ 51	$ 48	44	$ 51	55
Loans individually evaluated for impairment					34		37
Loans collectively evaluated for impairment					4,349		4,473
Total loans					$ 4,383		$ 4,510