DEBT OUTSTANDING (Details 2) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended						12 Months Ended			24 Months Ended					1 Months Ended	12 Months Ended	3 Months Ended		12 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended		12 Months Ended	3 Months Ended	12 Months Ended
	Nov. 30, 2011 USD ($)	Dec. 31, 2012 USD ($)	Jun. 30, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Jun. 30, 2011 USD ($)	Mar. 31, 2011 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2008 Junior subordinated debt USD ($) item	Dec. 31, 2012 Series A-3 Junior Subordinated Debentures	Dec. 31, 2012 Series A-2 Junior Subordinated Debentures	Dec. 31, 2012 Series A-4 Junior Subordinated Debentures	Dec. 31, 2012 Series A-5 Junior Subordinated Debentures	Aug. 31, 2012 Subordinated Notes USD ($)	Dec. 31, 2012 Subordinated Notes	Dec. 31, 2011 Exchange of notes Series A-1 Junior Subordinated Debentures USD ($)	Dec. 31, 2011 Exchange of notes Series A-2 and Series A-8 Junior Subordinated Debentures GBP (£)	Dec. 31, 2011 Exchange of notes Series A-2 and Series A-8 Junior Subordinated Debentures USD ($)	Dec. 31, 2011 Exchange of notes Series A-3 Junior Subordinated Debentures EUR (€)	Dec. 31, 2011 Exchange of notes Series A-3 Junior Subordinated Debentures USD ($)	Dec. 31, 2011 Exchange of notes 6.820 percent new Dollar notes due November 15, 2037 USD ($)	Dec. 31, 2011 Exchange of notes 6.765 percent new Sterling notes due November 15, 2017 GBP (£)	Dec. 31, 2011 Exchange of notes 6.765 percent new Sterling notes due November 15, 2017 USD ($)	Dec. 31, 2011 Exchange of notes 6.797 percent Euro notes due November 15, 2017 EUR (€)	Dec. 31, 2011 Exchange of notes 6.797 percent Euro notes due November 15, 2017 USD ($)
Senior Notes Offering
Amount of debt issued											$ 12,500					$ 250
Number of series of securities in which debt is issued											8
Original amount of debt converted									2,392									312	812	1,260	591	766
Converted amount debt instrument									1,843														256	662	1,030	421	545
Interest rate (as a percent)												4.875%	5.75%	6.45%	7.70%	2.375%							6.82%	6.765%	6.765%	6.797%	6.797%
Deferred gain on conversion of debt	65
Net gain (loss) on extinguishment of debt	$ 484	$ 41	$ (11)	$ (21)	$ 484	$ (79)	$ (3,313)	$ (9)	$ (2,847)	$ (104)
Period prior to the date of repayment, redemption or purchase within which a specified amount of net cash proceeds is to be received																	360 days