XML 41 R29.htm IDEA: XBRL DOCUMENT v3.5.0.2
Accounts Receivable, Net (Details) - USD ($)
$ in Millions
Jun. 30, 2016
Dec. 31, 2015
Receivables [Abstract]    
Allowance for bill adjustments and uncollectible accounts $ 73 $ 74
Accounts receivable greater than 90 days old $ 61 $ 50