DERIVATIVE INSTRUMENTS - Fair Value and Notional Amounts of Derivatives With Counterparty Credit Risk (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Fair Value of Swaps	$ (589)	$ (156)
Notional Amount of Swaps	13,370	5,491
AA
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Fair Value of Swaps	(1)	0
Notional Amount of Swaps	161	0
A
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Fair Value of Swaps	(588)	(156)
Notional Amount of Swaps	$ 13,209	$ 5,491