XML 147 R55.htm IDEA: XBRL DOCUMENT v3.8.0.1
Main items related to operating activities - Valuation allowances and overdue receivables (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Main items related to operating activities      
Overdue receivables $ 3,156 $ 3,525 $ 3,159
Due in less than 90 days      
Main items related to operating activities      
Overdue receivables 1,682 1,273 1,313
Due between 90 days and 6 months      
Main items related to operating activities      
Overdue receivables 235 1,013 460
Due between 6 and 12 months      
Main items related to operating activities      
Overdue receivables 350 538 570
Due after 12 months      
Main items related to operating activities      
Overdue receivables 889 701 816
Accounts receivable, net      
Reconciliation of changes in allowance account for credit losses of financial assets [abstract]      
Valuation allowance as of the beginning of the period (596) (544) (602)
Increase (net) 53 (17) 5
Currency translation adjustment and other variations (33) (35) 53
Valuation allowance as of the end of the period (576) (596) (544)
Other current assets      
Reconciliation of changes in allowance account for credit losses of financial assets [abstract]      
Valuation allowance as of the beginning of the period (400) (426) (367)
Increase (net) (58) 33 (79)
Currency translation adjustment and other variations (3) (7) 20
Valuation allowance as of the end of the period $ (461) $ (400) $ (426)