Income Taxes - Reconciliation of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Reconciliation [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent									35.00%	35.00%	35.00%
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Computed Tax (Expense) Benefit at Statutory Rate									$ (295)	$ (99)	$ (83)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount									(31)	(15)	(8)
Effect of Earnings in Jurisdictions outside of the United States									24	30	13
Change in Valuation Allowance									139	3,401	205
Disallowed Interest									(58)	(62)	(25)
Non-Deductible Deconsolidation Loss									0	(57)	0
Other Permanent Items									(33)	(25)	(19)
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount									22	0	0
Effective Income Tax Rate Reconciliation, Federal Law Changes									110	0	0
Indefinite-lived assets									0	0	2
Uncertain Tax Positions									(2)	(5)	3
Change in Tax Rate									(24)	(20)	(7)
Other, net									(17)	2	(5)
Income Tax Benefit (Expense)	$ 33	$ (74)	$ (34)	$ (90)	$ 3,189	$ (16)	$ (18)	$ (5)	$ (165)	$ 3,150	$ 76