Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income Taxes (Textuals) [Abstract]
Tax Expense	$ 120	$ 60	$ 243	$ 68
Income (Loss) before Income Taxes	328	$ 292	687	$ 262
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	3		8
Deferred Tax Asset Valuation Allowance Release Reasonably Possible Tax Benefit	$ 300		$ 300
Unrecognized tax benefits					$ 81
Favorable impact of unrecognized tax benefits if recognized					65
Accrued interest					15
Unsettled unrecognized tax benefits that would require cash					26
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit					15
Accrued Interest Favorably Settled In Next Twelve Months					$ 5