PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS - Aggregate Notional Amount of Derivatives (Details) (Qualified and Registered Pension Plans, USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Defined Benefit Plan Disclosure [Line Items]
Notional Amount of Derivatives	$ 1,889	$ 1,834
Equity index instruments
Defined Benefit Plan Disclosure [Line Items]
Notional Amount of Derivatives	390	393
Forward contracts
Defined Benefit Plan Disclosure [Line Items]
Notional Amount of Derivatives	208	221
Swaps
Defined Benefit Plan Disclosure [Line Items]
Notional Amount of Derivatives	$ 1,291	$ 1,220