Registration of securities issued in business combination transactions

Schedule II - Valuation and Qualifying Accounts (Details)

v3.3.1.900
Schedule II - Valuation and Qualifying Accounts (Details) - Allowance for doubtful accounts - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Valuation and Qualifying Accounts      
Balance at beginning of period $ 34 $ 42 $ 47
Charges (credits) to cost and expenses 1   2
Charged to other accounts (9) (8) (7)
Balance at end of period $ 26 $ 34 $ 42