BENEFITS Benefits - Fair Value of Assets by Category (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan, Fair Value of Plan Assets		$ 126	$ 118
Cash and Cash Equivalents
Defined Benefit Plan, Fair Value of Plan Assets		8	3
Mutual Fund
Defined Benefit Plan, Fair Value of Plan Assets	[1]	0	115
Fixed Income Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	[1]	112	0
Balanced Funds [Member]
Defined Benefit Plan, Fair Value of Plan Assets	[1]	$ 6	$ 0

[1] This fund of funds invests primarily in a diversified portfolio of equity, fixed income and short-term mutual funds. As of December 31, 2015, the fund was primarily comprised of 36% equities, 54% fixed income securities, and 10% cash.