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INVESTMENTS (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2011 score M trust policy Y category	Jun. 30, 2011	Sep. 30, 2010	Mar. 31, 2010 security	Sep. 30, 2011 M trust policy Y category	Sep. 30, 2010	Dec. 31, 2010
Interest and dividends on all investments
Taxable interest	$ 1,720		$ 2,353		$ 5,777	$ 7,896
Interest exempt from U.S. federal income tax	148		125		441	364
Dividends	57		73		243	255
Total interest and dividends	1,925		2,551		6,461	8,515
Gross realized investments losses, excluding losses from other-than-temporary impairment
Gross realized investment gains	920		1,133		2,224	2,280
Gross realized investment losses	(155)		(171)		(296)	(257)
Net realized gains	765		962		1,928	2,023
Number of debt securities				4
Carrying value of held-to-maturity investments sold	985	82		413	985
Loss realized on sale of held to maturity securities	123	15		49
Available-for-sale Securities, Debt Maturities
Total amortized cost	251,292				251,292		269,566
Total fair value	252,791				252,791		268,612
Minimum contractual maturities of investments with no stated maturities, included as contractual maturities (in years)	10				10
Mortgage-backed securities
Available-for-sale Securities, Debt Maturities
After 1 but within 5 years, amortized cost	455				455		403
After 5 but within 10 years, amortized cost	1,708				1,708		402
After 10 years, amortized cost	41,690				41,690		25,685
Total amortized cost	43,853				43,853		26,490
Fair value, after 1 but within 5 years	443				443		375
Fair value, after 5 but within 10 years	1,767				1,767		419
Fair value, after 10 years	43,051				43,051		25,712
Total fair value	45,261				45,261		26,506
U.S. Treasury and federal agency securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	8,777				8,777		36,411
After 1 but within 5 years, amortized cost	61,797				61,797		52,558
After 5 but within 10 years, amortized cost	8,067				8,067		10,604
After 10 years, amortized cost	882				882		1,790
Total amortized cost	79,523				79,523		101,363
Fair value, due within 1 year	8,806				8,806		36,443
Fair value, after 1 but within 5 years	63,225				63,225		53,118
Fair value, after 5 but within 10 years	8,544				8,544		10,647
Fair value, after 10 years	939				939		1,854
Total fair value	81,514				81,514		102,062
State and municipal securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	49				49		9
After 1 but within 5 years, amortized cost	432				432		145
After 5 but within 10 years, amortized cost	198				198		230
After 10 years, amortized cost	16,139				16,139		15,276
Total amortized cost	16,818				16,818		15,660
Fair value, due within 1 year	49				49		9
Fair value, after 1 but within 5 years	434				434		149
Fair value, after 5 but within 10 years	203				203		235
Fair value, after 10 years	13,694				13,694		12,842
Total fair value	14,380				14,380		13,235
Foreign government
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	33,282				33,282		41,856
After 1 but within 5 years, amortized cost	41,332				41,332		49,983
After 5 but within 10 years, amortized cost	7,186				7,186		6,143
After 10 years, amortized cost	957				957		1,128
Total amortized cost	82,757				82,757		99,110
Fair value, due within 1 year	33,198				33,198		41,387
Fair value, after 1 but within 5 years	41,489				41,489		50,739
Fair value, after 5 but within 10 years	7,188				7,188		6,264
Fair value, after 10 years	1,113				1,113		1,289
Total fair value	82,988				82,988		99,679
All other.
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	9,943				9,943		2,162
After 1 but within 5 years, amortized cost	10,355				10,355		17,838
After 5 but within 10 years, amortized cost	3,102				3,102		2,610
After 10 years, amortized cost	4,941				4,941		4,333
Total amortized cost	28,341				28,341		26,943
Fair value, due within 1 year	9,960				9,960		2,164
Fair value, after 1 but within 5 years	10,500				10,500		17,947
Fair value, after 5 but within 10 years	3,260				3,260		2,714
Fair value, after 10 years	4,928				4,928		4,305
Total fair value	$ 28,648				$ 28,648		$ 27,130