INVESTMENTS (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investments summary
Securities available-for-sale, at fair value	$ 281,749	$ 288,695
Debt securities held-to-maturity	10,056	10,130
Non-marketable equity securities carried at fair value	5,590	5,768
Non-marketable equity securities carried at cost	7,464	7,733
Total investments	304,859	312,326
Securities available-for-sale
Fair value	281,749	288,695
Mortgage-backed securities
Investments summary
Securities available-for-sale, at fair value	58,152	55,471
Debt securities held-to-maturity	3,751	4,709
Securities available-for-sale
Amortized cost	56,880	53,965
Gross unrealized gains	1,476	1,672
Gross unrealized losses	204	166
Fair value	58,152	55,471
U.S. government-sponsored agency guaranteed
Investments summary
Securities available-for-sale, at fair value	48,645	47,345
Securities available-for-sale
Amortized cost	47,590	46,001
Gross unrealized gains	1,254	1,507
Gross unrealized losses	199	163
Fair value	48,645	47,345
Prime
Investments summary
Securities available-for-sale, at fair value	162	86
Debt securities held-to-maturity	109	209
Securities available-for-sale
Amortized cost	156	85
Gross unrealized gains	6	1
Fair value	162	86
Alt-A
Investments summary
Securities available-for-sale, at fair value	569	1
Debt securities held-to-maturity	1,518	2,132
Securities available-for-sale
Amortized cost	517	1
Gross unrealized gains	52
Fair value	569	1
Subprime
Investments summary
Securities available-for-sale, at fair value	62
Debt securities held-to-maturity	74	158
Securities available-for-sale
Amortized cost	62
Fair value	62
Non-U.S. residential
Investments summary
Securities available-for-sale, at fair value	8,279	7,590
Debt securities held-to-maturity	1,960	2,087
Securities available-for-sale
Amortized cost	8,132	7,442
Gross unrealized gains	150	148
Gross unrealized losses	3
Fair value	8,279	7,590
Commercial
Investments summary
Securities available-for-sale, at fair value	435	449
Debt securities held-to-maturity	90	123
Securities available-for-sale
Amortized cost	423	436
Gross unrealized gains	14	16
Gross unrealized losses	2	3
Fair value	435	449
U.S. Treasury and federal agency securities
Investments summary
Securities available-for-sale, at fair value	87,916	91,841
Securities available-for-sale
Amortized cost	86,676	90,300
Gross unrealized gains	1,353	1,576
Gross unrealized losses	113	35
Fair value	87,916	91,841
U.S. Treasury
Investments summary
Securities available-for-sale, at fair value	65,828	65,594
Securities available-for-sale
Amortized cost	64,931	64,456
Gross unrealized gains	1,009	1,172
Gross unrealized losses	112	34
Fair value	65,828	65,594
Agency obligations
Investments summary
Securities available-for-sale, at fair value	22,088	26,247
Securities available-for-sale
Amortized cost	21,745	25,844
Gross unrealized gains	344	404
Gross unrealized losses	1	1
Fair value	22,088	26,247
State and municipal securities
Investments summary
Securities available-for-sale, at fair value	18,646	18,332
Debt securities held-to-maturity	1,271	1,205
Securities available-for-sale
Amortized cost	20,148	20,020
Gross unrealized gains	438	132
Gross unrealized losses	1,940	1,820
Fair value	18,646	18,332
Foreign government
Investments summary
Securities available-for-sale, at fair value	87,122	94,047
Debt securities held-to-maturity	3,816	2,987
Securities available-for-sale
Amortized cost	86,463	93,259
Gross unrealized gains	808	918
Gross unrealized losses	149	130
Fair value	87,122	94,047
Corporate
Investments summary
Securities available-for-sale, at fair value	10,050	9,674
Debt securities held-to-maturity	724	726
Securities available-for-sale
Amortized cost	9,699	9,302
Gross unrealized gains	365	398
Gross unrealized losses	14	26
Fair value	10,050	9,674
Asset-backed securities
Investments summary
Securities available-for-sale, at fair value	14,717	14,130
Debt securities held-to-maturity	494	503
Securities available-for-sale
Amortized cost	14,722	14,188
Gross unrealized gains	105	85
Gross unrealized losses	110	143
Fair value	14,717	14,130
Other debt securities
Investments summary
Securities available-for-sale, at fair value	257	258
Securities available-for-sale
Amortized cost	256	256
Gross unrealized gains	1	2
Fair value	257	258
Total debt securities AFS
Investments summary
Securities available-for-sale, at fair value	276,860	283,753
Securities available-for-sale
Amortized cost	274,844	281,290
Gross unrealized gains	4,546	4,783
Gross unrealized losses	2,530	2,320
Fair value	276,860	283,753
Marketable equity securities AFS
Investments summary
Securities available-for-sale, at fair value	4,889	4,942
Securities available-for-sale
Amortized cost	4,447	4,643
Gross unrealized gains	585	444
Gross unrealized losses	143	145
Fair value	4,889	4,942
Total securities AFS
Investments summary
Securities available-for-sale, at fair value	281,749	288,695
Securities available-for-sale
Amortized cost	279,291	285,933
Gross unrealized gains	5,131	5,227
Gross unrealized losses	2,673	2,465
Fair value	$ 281,749	$ 288,695

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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