DEBT (Details 2) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Long-Term Debt:
Total long-term debt	$ 221,593,000,000	$ 239,463,000,000
Trust assets	0
Junior subordinated notes relating to trust preferred securities
Long-Term Debt:
Total long-term debt	4,300,000,000	10,100,000,000
Citigroup Inc.
Long-Term Debt:
Total long-term debt	159,698,000,000	176,553,000,000
Bank
Long-Term Debt:
Total long-term debt	53,004,000,000	51,234,000,000
Collateralized long-term advances from Federal Home Loan Bank	14,300,000,000	16,300,000,000
Broker-dealer
Long-Term Debt:
Total long-term debt	8,891,000,000	11,676,000,000
Citigroup Funding Inc. (CFI)
Long-Term Debt:
Carrying value of Principal-Protected Trust Securities	$ 124,000,000	$ 186,000,000