GOODWILL AND INTANGIBLE ASSETS (Details 2) (USD $) In Millions, unless otherwise specified					3 Months Ended
Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Jun. 30, 2011 North America Regional Consumer Banking	Jun. 30, 2011 EMEA Regional Consumer Banking	Jun. 30, 2011 Asia Regional Consumer Banking	Jun. 30, 2011 Latin America Regional Consumer Banking	Jun. 30, 2011 Securities and Banking	Jun. 30, 2011 Transaction Services	Jun. 30, 2011 Brokerage and Asset Management.	Jun. 30, 2011 Local Consumer Lending-Cards	Jun. 30, 2011 Regional Consumer Banking	Jun. 30, 2011 Institutional Clients Group	Jun. 30, 2011 Citi Holdings
Goodwill:
Goodwill	$ 26,621	$ 26,339	$ 26,152	$ 2,530	$ 355	$ 6,303	$ 1,865	$ 9,492	$ 1,579	$ 68	$ 4,429	$ 11,053	$ 11,071	$ 4,497
Fair value as a percentage of allocated book value (as a percent)											120.00%

Carrying amount as of the balance sheet date, which is the cumulative amount paid, adjusted for any amortization recognized prior to adoption of FAS 142 and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43

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