XML 81 R69.htm IDEA: XBRL DOCUMENT v3.10.0.1
Debt (Estimated Fair Value of Significant Financial Instruments) (Details) - USD ($)
$ in Millions
Sep. 30, 2018
Dec. 31, 2017
Carrying Amount    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Short-term debt $ 638 $ 262
Long-term debt 5,512 5,225
Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Short-term debt 637 264
Long-term debt $ 5,477 $ 5,444