INVESTMENTS (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Available-for-sale Securities, Debt Maturities
Total amortized cost	$ 274,737		$ 274,737		$ 281,710
Total fair value	273,486		273,486		283,753
Minimum contractual maturities of investments with no stated maturities, included as contractual maturities			10 years
Available-for-sale Securities transferred from Held-to-maturity
Carrying value of held-to-maturity investments sold	318		485	1,243
Loss realized on sale of held to maturity securities	56		66	169
Carrying value of securities reclassified as available-for-sale	300		902	107
OTTI recorded for available-for-sale investments transferred from held-to-maturity	61		155	26
Interest and dividends on investments
Taxable interest	1,381	1,604	2,891	3,264
Interest exempt from U.S. federal income tax	198	166	370	340
Dividends	108.0	84.0	228.0	160.0
Total interest and dividends	1,687	1,854	3,489	3,764
Gross realized investments losses, excluding losses from other-than-temporary impairment
Gross realized investment gains	620	329	1,114	2,495
Gross realized investment losses	(369)	(56)	(413)	(297)
Net realized gains (losses)	251	273	701	2,198
Mortgage-backed securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	26		26		10
After 1 but within 5 years, amortized cost	363		363		365
After 5 but within 10 years, amortized cost	2,233		2,233		1,992
After 10 years, amortized cost	56,101		56,101		51,598
Total amortized cost	58,723		58,723		53,965
Fair value, due within 1 year	26		26		10
Fair value, after 1 but within 5 years	372		372		374
Fair value, after 5 but within 10 years	2,283		2,283		2,124
Fair value, after 10 years	56,117		56,117		52,963
Total fair value	58,798		58,798		55,471
U.S. Treasury and federal agency securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	13,092		13,092		9,387
After 1 but within 5 years, amortized cost	66,233		66,233		76,454
After 5 but within 10 years, amortized cost	1,901		1,901		2,171
After 10 years, amortized cost	2,851		2,851		2,669
Total amortized cost	84,077		84,077		90,681
Fair value, due within 1 year	13,114		13,114		9,499
Fair value, after 1 but within 5 years	66,499		66,499		77,267
Fair value, after 5 but within 10 years	2,019		2,019		2,408
Fair value, after 10 years	2,930		2,930		2,667
Total fair value	84,562		84,562		91,841
State and municipal securities
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	187		187		208
After 1 but within 5 years, amortized cost	3,220		3,220		3,221
After 5 but within 10 years, amortized cost	201		201		155
After 10 years, amortized cost	15,577		15,577		16,436
Total amortized cost	19,185		19,185		20,020
Fair value, due within 1 year	187		187		208
Fair value, after 1 but within 5 years	3,216		3,216		3,223
Fair value, after 5 but within 10 years	207		207		165
Fair value, after 10 years	13,719		13,719		14,736
Total fair value	17,329		17,329		18,332
Foreign government
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	33,166		33,166		34,873
After 1 but within 5 years, amortized cost	46,835		46,835		49,587
After 5 but within 10 years, amortized cost	5,417		5,417		7,239
After 10 years, amortized cost	933		933		1,599
Total amortized cost	86,351		86,351		93,298
Fair value, due within 1 year	33,154		33,154		34,869
Fair value, after 1 but within 5 years	46,778		46,778		49,933
Fair value, after 5 but within 10 years	5,373		5,373		7,380
Fair value, after 10 years	1,002		1,002		1,865
Total fair value	86,307		86,307		94,047
All other
Available-for-sale Securities, Debt Maturities
Due within 1 year, amortized cost	2,379		2,379		1,001
After 1 but within 5 years, amortized cost	10,302		10,302		11,285
After 5 but within 10 years, amortized cost	5,533		5,533		4,330
After 10 years, amortized cost	8,187		8,187		7,130
Total amortized cost	26,401		26,401		23,746
Fair value, due within 1 year	2,335		2,335		1,009
Fair value, after 1 but within 5 years	10,392		10,392		11,351
Fair value, after 5 but within 10 years	5,582		5,582		4,505
Fair value, after 10 years	8,181		8,181		7,197
Total fair value	$ 26,490		$ 26,490		$ 24,062