Asset Backed Securities, Average Remaining Term

No definition available.

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- Definition

Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity or available-for-sale where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity and available-for-sale investments determined to be temporarily impaired.

+ References

No definition available.

+ Details

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- Definition

Collective Credit Support Percentage Minimum

+ References

No definition available.

+ Details

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- Definition

Federal Government Credit Support Guarantee Percentage Minimum

+ References

No definition available.

+ Details

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- Definition

Impairment associated with adverse changes in timing of expected future cash flows

+ References

No definition available.

+ Details

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- Definition

Impairment associated with expected credit losses

+ References

No definition available.

+ Details

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- Definition

Number of peripheral european countries.

+ References

No definition available.

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- Definition

Percentage change in additional house price declines.

+ References

No definition available.

+ Details

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- Definition

Modest Recovery of Claimed Amounts

+ References

No definition available.

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- Definition

Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 8, 9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

This item represents the gross unrealized losses for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References

No definition available.

+ Details

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- Definition

Maximum amount of loss due to credit risk that, based on the gross fair value of the financial instrument, the entity would incur if parties to the financial instruments that make up the concentration failed completely to perform according to the terms of the contracts and the collateral or other security, if any, for the amount due proved to be of no value to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (b)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15A

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15C

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=16383099&loc=d3e25351-111560

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-2/124-2

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

This item represents the total unrealized gain (loss) included in earnings for the period as a result of holding marketable securities categorized as trading, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)(1)(i)

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-Name FASB Staff Position (FSP)

-Number FAS140-4/FIN46(R)-8

-Paragraph B6

-Subparagraph b

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Investment Securities (Narrative) (Details) (USD $)	3 Months Ended
Investment Securities (Narrative) (Details) (USD $)	Mar. 31, 2013 security country	Mar. 31, 2012	Dec. 31, 2012
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Aggregate investment securities carried	$ 47,010,000,000		$ 46,660,000,000
Impairment associated with expected credit losses	0	4,000,000
Net impairment losses	3,000,000	8,000,000
Impairment associated with adverse changes in timing of expected future cash flows	3,000,000	4,000,000
Aggregate pre-tax gross unrealized loss on available for sale securities	631,000,000		882,000,000
Number of peripheral european countries	4
Recovery of claimed amounts	20.00%
Gross pre-tax unrealized losses on securities	(753,000,000)
Number of available for sale and held to maturity securities in gross pre-tax unrealized loss position	1,423
European Periphery
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Total exposure to asset backed Securities	563,000,000
Aggregate pre-tax gross unrealized loss on available for sale securities	29,000,000
Spain
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Total exposure to asset backed Securities	264,000,000
Italy
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Total exposure to asset backed Securities	114,000,000
Ireland
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Total exposure to asset backed Securities	110,000,000
Portugal
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Total exposure to asset backed Securities	75,000,000
Federal Family Education Loan Program
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Federal government credit support guarantee, percentage minimum	97.00%
Collective credit support, percentage minimum	100.00%
Average remaining term of FFELP loan-backed securities	5 years 1 month 6 days
Maximum concentration risk on credit instruments	900,000,000
Non-U.S. debt securities, mortgage-backed securities
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Net impairment losses	3,000,000
Aggregate pre-tax gross unrealized loss on available for sale securities	22,000,000		27,000,000
Non-Agency Prime [Member]
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Impairment associated with expected credit losses		4,000,000
Net impairment losses	3,000,000	8,000,000
Impairment associated with adverse changes in timing of expected future cash flows		$ 4,000,000
Minimum
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Percentage change in additional house price declines	10.00%
Maximum
Available-For-Sale and Held-To-Maturity-Securities [Line Items]
Percentage change in additional house price declines	19.00%