XML 61 R43.htm IDEA: XBRL DOCUMENT v3.8.0.1
Debt - Letters of Credit, Borrowings and Repayments (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Debt      
Outstanding letters of credit $ 102   $ 166
Credit facilities and commercial paper program      
Debt      
Total borrowings 10,500 $ 18,800  
Total repayments $ 10,700 $ 19,200