Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]
Defined Benefit Plan, Curtailments	$ 55
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments		$ 86
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%	3.10%	3.85%	3.60%