INVESTMENTS (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 Y	Mar. 31, 2011	Dec. 31, 2011 Y
Available-for-sale Securities, Debt Maturities
Total amortized cost	$ 266,611		$ 255,656
Total fair value	268,159		257,019
Minimum contractual maturities of investments with no stated maturities, included as contractual maturities (in years)	10		10
Interest and dividends on all investments
Taxable interest	1,660	2,121
Interest exempt from U.S. federal income tax	174	221
Dividends	76	69
Total interest and dividends	1,910	2,411
Gross realized investments losses, excluding losses from other-than-temporary impairment
Gross realized investment gains	2,166	680
Gross realized investment losses	(241)	(100)
Net realized gains	1,925	580
HTM debt securities
Available-for-sale Securities, Debt Maturities
Carrying value of held-to-maturity investments sold	967
Loss realized on sale of held to maturity securities	144
Carrying value of securities reclassified as available-for-sale	39
Other-than-temporary-impairment loss	(13)
Mortgage-backed securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	16
After 1 but within 5 years, amortized cost	429		422
After 5 but within 10 years, amortized cost	2,031		2,757
After 10 years, amortized cost	48,459		46,470
Total amortized cost	50,935		49,649
Fair value, due within 1 year	16
Fair value, after 1 but within 5 years	431		423
Fair value, after 5 but within 10 years	2,104		2,834
Fair value, after 10 years	49,583		47,768
Total fair value	52,134		51,025
U.S. Treasury and federal agency securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	17,667		14,615
After 1 but within 5 years, amortized cost	65,596		62,241
After 5 but within 10 years, amortized cost	4,201		5,862
After 10 years, amortized cost	59		382
Total amortized cost	87,523		83,100
Fair value, due within 1 year	17,687		14,637
Fair value, after 1 but within 5 years	66,914		63,823
Fair value, after 5 but within 10 years	4,515		6,239
Fair value, after 10 years	58		439
Total fair value	89,174		85,138
State and municipal securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	138		142
After 1 but within 5 years, amortized cost	498		455
After 5 but within 10 years, amortized cost	194		182
After 10 years, amortized cost	15,188		16,040
Total amortized cost	16,018		16,819
Fair value, due within 1 year	139		142
Fair value, after 1 but within 5 years	500		457
Fair value, after 5 but within 10 years	204		188
Fair value, after 10 years	13,301		13,612
Total fair value	14,144		14,399
Foreign government
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	31,140		34,924
After 1 but within 5 years, amortized cost	49,469		41,612
After 5 but within 10 years, amortized cost	7,121		6,993
After 10 years, amortized cost	1,251		831
Total amortized cost	88,981		84,360
Fair value, due within 1 year	31,112		34,864
Fair value, after 1 but within 5 years	49,215		41,675
Fair value, after 5 but within 10 years	7,554		6,998
Fair value, after 10 years	1,396		977
Total fair value	89,277		84,514
All other
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	3,814		4,055
After 1 but within 5 years, amortized cost	10,863		9,843
After 5 but within 10 years, amortized cost	3,873		3,009
After 10 years, amortized cost	4,604		4,821
Total amortized cost	23,154		21,728
Fair value, due within 1 year	3,827		4,072
Fair value, after 1 but within 5 years	10,980		9,928
Fair value, after 5 but within 10 years	4,026		3,160
Fair value, after 10 years	4,597		4,783
Total fair value	$ 23,430		$ 21,943