REGULATORY CAPITAL AND CITIGROUP INC. PARENT COMPANY INFORMATION (Details 2) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Revenues
Interest revenue									$ 62,970,000,000		$ 67,298,000,000		$ 71,858,000,000
Interest expense									16,177,000,000		20,612,000,000		24,209,000,000
Net interest revenue									46,793,000,000		46,686,000,000		47,649,000,000
Non-interest revenue									29,573,000,000		22,442,000,000		29,682,000,000
Total revenues, net of interest expense	17,780,000,000	17,880,000,000	20,479,000,000	20,227,000,000	17,917,000,000	13,703,000,000	18,387,000,000	19,121,000,000	76,366,000,000		69,128,000,000		77,331,000,000
Total operating expenses	12,293,000,000	11,655,000,000	12,140,000,000	12,267,000,000	13,709,000,000	12,092,000,000	11,994,000,000	12,179,000,000	48,355,000,000	[1]	49,974,000,000	[1]	50,250,000,000	[1]
Income (loss) from continuing operations before income taxes	3,415,000,000	4,266,000,000	6,315,000,000	5,501,000,000	1,095,000,000	(1,009,000,000)	3,697,000,000	4,042,000,000	19,497,000,000		7,825,000,000		14,722,000,000
Income taxes (benefits)	1,090,000,000	1,080,000,000	2,127,000,000	1,570,000,000	(214,000,000)	(1,494,000,000)	718,000,000	997,000,000	5,867,000,000		7,000,000		3,575,000,000
Citigroup's net income	2,456,000,000	3,227,000,000	4,182,000,000	3,808,000,000	1,196,000,000	468,000,000	2,946,000,000	2,931,000,000	13,673,000,000		7,541,000,000		11,067,000,000
Comprehensive income
Parent company's net income	2,456,000,000	3,227,000,000	4,182,000,000	3,808,000,000	1,196,000,000	468,000,000	2,946,000,000	2,931,000,000	13,673,000,000		7,541,000,000		11,067,000,000
Other comprehensive income (loss)									(2,237,000,000)		892,000,000		(1,511,000,000)
Citigroup's comprehensive income									11,436,000,000		8,433,000,000		9,556,000,000
Assets
Cash and deposits from banks	29,885,000,000				36,453,000,000				29,885,000,000		36,453,000,000		28,701,000,000
Trading account assets	285,928,000,000				320,929,000,000				285,928,000,000		320,929,000,000
Other assets	125,266,000,000				145,660,000,000				125,266,000,000		145,660,000,000
Total assets	1,880,382,000,000				1,864,660,000,000				1,880,382,000,000		1,864,660,000,000
Liabilities
Trading account liabilities	108,762,000,000				115,549,000,000				108,762,000,000		115,549,000,000
Short-term borrowings	58,944,000,000				52,027,000,000				58,944,000,000		52,027,000,000
Long-term debt	221,116,000,000				239,463,000,000				221,116,000,000		239,463,000,000
Other liabilities	59,935,000,000				67,815,000,000				59,935,000,000		67,815,000,000
Total liabilities	1,674,249,000,000				1,673,663,000,000				1,674,249,000,000		1,673,663,000,000
Total Citigroup stockholders' equity	204,339,000,000				189,049,000,000				204,339,000,000		189,049,000,000
Total liabilities and equity	1,880,382,000,000				1,864,660,000,000				1,880,382,000,000		1,864,660,000,000
Citigroup Inc. Parent Company Only, Cash Flows Statement
Net cash provided by (used in ) operating activities of continuing operations									57,410,000,000		14,265,000,000		64,795,000,000
Cash flows from investing activities of continuing operations
Purchases of investments									(220,823,000,000)		(256,907,000,000)		(314,250,000,000)
Proceeds from sales of investments									131,100,000,000		143,853,000,000		182,566,000,000
Proceeds from maturities of investments									84,831,000,000		102,020,000,000		139,959,000,000
Net cash provided by (used in) investing activities of continuing operations									(93,306,000,000)		18,571,000,000		(8,772,000,000)
Cash flows from financing activities of continuing operations
Dividends paid									(314,000,000)		(143,000,000)		(107,000,000)
Issuance of preferred stock									4,270,000,000		2,250,000,000
Net cash provided by (used in) financing activities of continuing operations									30,896,000,000		(25,364,000,000)		(56,646,000,000)
Change in cash and due from banks									(6,568,000,000)		7,752,000,000		729,000,000
Cash and due from banks at beginning of year				36,453,000,000				28,701,000,000	36,453,000,000		28,701,000,000		27,972,000,000
Cash and due from banks at end of year	29,885,000,000				36,453,000,000				29,885,000,000		36,453,000,000		28,701,000,000
Cash paid (received) during the year for
Income taxes									4,495,000,000		3,900,000,000		2,705,000,000
Interest									14,383,000,000		19,739,000,000		21,230,000,000
Citigroup Parent Company
Revenues
Interest revenue									3,234,000,000		3,384,000,000		3,684,000,000
Interest expense									5,559,000,000		6,573,000,000		7,618,000,000
Net interest revenue									(2,325,000,000)		(3,189,000,000)		(3,934,000,000)
Dividends from subsidiaries									13,044,000,000		20,780,000,000		13,046,000,000
Non-interest revenue									139,000,000		613,000,000		939,000,000
Total revenues, net of interest expense									10,858,000,000		18,204,000,000		10,051,000,000
Total operating expenses									851,000,000		1,497,000,000		1,503,000,000
Income (loss) from continuing operations before income taxes									10,007,000,000		16,707,000,000		8,548,000,000
Income taxes (benefits)									(1,637,000,000)		(2,062,000,000)		(1,821,000,000)
Equity in undistributed income (loss) of subsidiaries									2,029,000,000		(11,228,000,000)		698,000,000
Citigroup's net income									13,673,000,000		7,541,000,000		11,067,000,000
Comprehensive income
Parent company's net income									13,673,000,000		7,541,000,000		11,067,000,000
Other comprehensive income (loss)									(2,237,000,000)		892,000,000		(1,511,000,000)
Citigroup's comprehensive income									11,436,000,000		8,433,000,000		9,556,000,000
Assets
Cash and deposits from banks	233,000,000				153,000,000				233,000,000		153,000,000		3,000,000
Trading account assets	184,000,000				150,000,000				184,000,000		150,000,000
Investments	1,032,000,000				1,676,000,000				1,032,000,000		1,676,000,000
Advances to subsidiaries	83,110,000,000				107,074,000,000				83,110,000,000		107,074,000,000
Investments in subsidiaries	203,739,000,000				184,615,000,000				203,739,000,000		184,615,000,000
Other assets	106,170,000,000				102,335,000,000				106,170,000,000		102,335,000,000
Total assets	394,468,000,000				396,003,000,000				394,468,000,000		396,003,000,000
Liabilities
Federal funds purchased and securities loaned or sold under agreements to repurchase	185,000,000				185,000,000				185,000,000		185,000,000
Trading account liabilities	165,000,000				170,000,000				165,000,000		170,000,000
Short-term borrowings	382,000,000				725,000,000				382,000,000		725,000,000
Long-term debt	156,804,000,000				176,553,000,000				156,804,000,000		176,553,000,000
Advances from subsidiaries other than banks	24,181,000,000				12,759,000,000				24,181,000,000		12,759,000,000
Other liabilities	8,412,000,000				16,562,000,000				8,412,000,000		16,562,000,000
Total liabilities	190,129,000,000				206,954,000,000				190,129,000,000		206,954,000,000
Total Citigroup stockholders' equity	204,339,000,000				189,049,000,000				204,339,000,000		189,049,000,000
Total liabilities and equity	394,468,000,000				396,003,000,000				394,468,000,000		396,003,000,000
Citigroup Inc. Parent Company Only, Cash Flows Statement
Net cash provided by (used in ) operating activities of continuing operations									(7,881,000,000)		1,598,000,000		1,710,000,000
Cash flows from investing activities of continuing operations
Purchases of investments											(5,701,000,000)		(47,190,000,000)
Proceeds from sales of investments									385,000,000		37,056,000,000		9,524,000,000
Proceeds from maturities of investments									233,000,000		4,286,000,000		22,386,000,000
Changes in investments and advances-intercompany									7,226,000,000		(397,000,000)		32,419,000,000
Other investing activities									4,000,000		994,000,000		(10,000,000)
Net cash provided by (used in) investing activities of continuing operations									7,848,000,000		36,238,000,000		17,129,000,000
Cash flows from financing activities of continuing operations
Dividends paid									(314,000,000)		(143,000,000)		(113,000,000)
Issuance of preferred stock									4,192,000,000		2,250,000,000
Proceeds (repayments) from issuance of long-term debt-third-party, net									(13,426,000,000)		(33,434,000,000)		(16,481,000,000)
Net change in short-term borrowings and other advances-intercompany									11,402,000,000		(6,160,000,000)		(5,772,000,000)
Other financing activities									(1,741,000,000)		(199,000,000)		3,519,000,000
Net cash provided by (used in) financing activities of continuing operations									113,000,000		(37,686,000,000)		(18,847,000,000)
Change in cash and due from banks									80,000,000		150,000,000		(8,000,000)
Cash and due from banks at beginning of year				153,000,000				3,000,000	153,000,000		3,000,000		11,000,000
Cash and due from banks at end of year	233,000,000				153,000,000				233,000,000		153,000,000		3,000,000
Cash paid (received) during the year for
Income taxes									(71,000,000)		78,000,000		(458,000,000)
Interest									6,514,000,000		7,883,000,000		9,271,000,000
Citibank, N.A.
Assets
Other assets	43,300,000,000				30,200,000,000				43,300,000,000		30,200,000,000
Other assets which have a remaining term of less than 30 days	$ 33,600,000,000				$ 28,200,000,000				$ 33,600,000,000		$ 28,200,000,000

[1] Citigroup recorded repositioning charges of $590 million for 2013, $1,375 million for 2012 and $706 million for 2011.