LOANS (Details 6) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Financing receivable
Loans at fair value	$ 4,840	$ 4,372
Loans, net of unearned income	647,500	648,794
Corporate.
Financing receivable
Loans, total current	195,082	179,233
Loans, total non-accrual	4,819	8,610
Private Banking loans managed on a delinquency basis	11,957	12,662
Loans at fair value	3,418	2,627
Loans, net of unearned income	204,456	191,162
Corporate. \| Mortgage and real estate
Financing receivable
Loans, total current	24,569	22,892
Loans, total non-accrual	1,911	1,782
Loans, net of unearned income	27,000	25,070
Corporate. \| Mortgage and real estate \| Investment Grade.
Financing receivable
Recorded investment in loans	9,494	8,119
Corporate. \| Mortgage and real estate \| Non-Investment Grade.
Financing receivable
Loans, total current	3,638	3,329
Loans, total non-accrual	1,911	1,782
Corporate. \| Commercial and industrial
Financing receivable
Loans, total current	87,069	76,862
Loans, total non-accrual	1,326	5,125
Loans, net of unearned income	88,579	82,120
Corporate. \| Commercial and industrial \| Investment Grade.
Financing receivable
Recorded investment in loans	59,731	51,042
Corporate. \| Commercial and industrial \| Non-Investment Grade.
Financing receivable
Loans, total current	27,521	25,992
Loans, total non-accrual	1,326	5,125
Corporate. \| Lease financing
Financing receivable
Loans, total current	1,947	1,890
Loans, total non-accrual	24	45
Loans, net of unearned income	1,989	1,944
Corporate. \| Lease financing \| Investment Grade.
Financing receivable
Recorded investment in loans	1,099	1,204
Corporate. \| Lease financing \| Non-Investment Grade.
Financing receivable
Loans, total current	866	695
Loans, total non-accrual	24	45
Corporate. \| Investment Grade.
Financing receivable
Recorded investment in loans	142,782	129,519
Corporate. \| Investment Grade. \| Other,
Financing receivable
Recorded investment in loans	23,322	21,844
Corporate. \| Non-Investment Grade.
Financing receivable
Loans, total non-accrual	46,299	46,354
Corporate. \| Non-Investment Grade. \| Other,
Financing receivable
Loans, total current	4,563	4,316
Loans, total non-accrual	439	400
Corporate. \| Other,
Financing receivable
Loans, total current	27,477	26,941
Loans, total non-accrual	439	400
Loans, net of unearned income	28,323	27,493
Corporate. \| Financial institutions
Financing receivable
Loans, total current	54,020	50,648
Loans, total non-accrual	1,119	1,258
Loans, net of unearned income	55,147	51,908
Corporate. \| Financial institutions \| Investment Grade.
Financing receivable
Recorded investment in loans	49,136	47,310
Corporate. \| Financial institutions \| Non-Investment Grade.
Financing receivable
Loans, total current	4,892	3,412
Loans, total non-accrual	$ 1,119	$ 1,258

Represents the recorded investment of financing receivable.

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- Definition

Financing receivables that are current.

+ Details

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Balance Type:	debit
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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ Details

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Namespace Prefix:	c
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the private banking loans managed on a delinquency basis.

+ Details

Name:	c_FinancingReceivableRecordedInvestmentPrivateBankingManagedOnDelinquencyBasis
Namespace Prefix:	c
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Reflects the aggregate gross carrying amount of all categories of loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on loans and leases.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Statement of Position (SOP)
-Number 01-6
-Paragraph 13
-Subparagraph e

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Audit and Accounting Guide (AAG)
-Number AAG-DEP
-Chapter 8
-Paragraph 116
-IssueDate 2006-05-01

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher OTS
-Name Federal Regulation (FR)
-Number Title 12
-Chapter V
-Section 563c.102
-Paragraph 8
-Subparagraph e
-Subsection I

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loan receivable as presented on the statement of financial position which may include mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts, or any other loans which are due the Company as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 114
-Paragraph 4

+ Details

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