Commercial Paper and Long-Term Debt Fair Value Hedges Effect of Changes in Fair Value Hedges on Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Net impact on the Company’s Consolidated Statements of Operations	$ 0	$ 0	$ 0
Interest Rate Swap [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedge - interest rate swap gain (loss) recognized in interest expense	75	170
Hedged item - long-term debt (loss) gain recognized in interest expense			(166)
Debt [Member] | Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedge - interest rate swap gain (loss) recognized in interest expense			$ 166
Hedged item - long-term debt (loss) gain recognized in interest expense	$ (75)	$ (170)