Annual report pursuant to Section 13 and 15(d)

Accounts Receivable (Activity in the Allowance for Doubtful Accounts) (Details)

v2.4.1.9
Accounts Receivable (Activity in the Allowance for Doubtful Accounts) (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Allowance for Doubtful Accounts Receivable [Roll Forward]      
Balance beginning of year $ 83us-gaap_AllowanceForDoubtfulAccountsReceivable $ 74us-gaap_AllowanceForDoubtfulAccountsReceivable $ 79us-gaap_AllowanceForDoubtfulAccountsReceivable
Additions- charged to expense 92us-gaap_ProvisionForDoubtfulAccounts 81us-gaap_ProvisionForDoubtfulAccounts 75us-gaap_ProvisionForDoubtfulAccounts
Deductions- write-offs (84)us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs (72)us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs (80)us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Balance end of year $ 91us-gaap_AllowanceForDoubtfulAccountsReceivable $ 83us-gaap_AllowanceForDoubtfulAccountsReceivable $ 74us-gaap_AllowanceForDoubtfulAccountsReceivable