CONCENTRATIONS OF CREDIT RISK (Details) (Investments, USD $) In Billions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
US Government and Government Agencies and Authorities
Concentration Risk
Credit exposure from investment securities, loans and trading assets	$ 190.7	$ 177.9
Japanese government and its agencies
Concentration Risk
Credit exposure from investment securities, loans and trading assets	38.7	33.2
Mexican government and its agencies
Concentration Risk
Credit exposure from investment securities, loans and trading assets	33.6	29.5
State and municipal securities
Concentration Risk
Credit exposure from investment securities, loans and trading assets	$ 35.8	$ 39.5

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.

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)

-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13537-108611

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

-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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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