DEBT (Details 2) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Long-Term Debt:
Total long-term debt	$ 222,747,000,000	$ 221,116,000,000
Trust assets	0
Trust preferred securities
Long-Term Debt:
Total long-term debt	3,900,000,000	3,900,000,000
Citigroup Inc.
Long-Term Debt:
Total long-term debt	155,229,000,000	156,804,000,000
Bank
Long-Term Debt:
Total long-term debt	60,079,000,000	56,457,000,000
Bank | Senior debt
Long-Term Debt:
Collateralized long-term advances from Federal Home Loan Bank	14,000,000,000	14,000,000,000
Broker-dealer
Long-Term Debt:
Total long-term debt	7,439,000,000	7,855,000,000
Citigroup Funding Inc. (CFI)
Long-Term Debt:
Carrying value of Principal-Protected Trust Securities	$ 51,000,000	$ 87,000,000