Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ (2,441)	$ 1,214	$ 978
Other Items of Comprehensive Income (Loss)
Net Change in Mutual Fund Investment	(11)	0	0
Less Tax Expense	4	0	0
Net Change in Pension and Other	99	42	(6)
Less Tax (Benefit) Expense	(35)	(15)	2
Other Comprehensive Income (Loss)	57	27	(4)
Comprehensive Income (Loss)	$ (2,384)	$ 1,241	$ 974