Income Taxes (Net Operating Loss Carryforwards and Tax Credit Carryforwards) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Internal Revenue Service (IRS) [Member]
Net Operating Loss Carryforwards	$ 878,000,000	$ 997,000,000
Tax Credit Carryforward	64,000,000	35,000,000
State and Local Jurisdiction [Member]
Net Operating Loss Carryforwards	2,272,000,000	2,594,000,000
Tax Credit Carryforward	$ 3,000,000	$ 7,000,000