Income and Other Taxes - Income Tax Expense (Benefit), Current Deferred, by Jurisdiction (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Current State Tax Expense (Benefit)	$ 15	$ (38)	$ 21
Current Federal Tax (Benefit) Expense	(15)	(225)	(58)
Deferred Federal Income Tax (Benefit) Expense	(4)	300	150
Current Foreign Tax Expense	71	73	83
Deferred Foreign Income Tax Expense (Benefit)	(13)	7	(16)
Deferred State Income Tax Expense	8	76	18
Total (Benefit) Provision	$ 62	$ 193	$ 198