Other Financial Data Schedule of Allowance for Doubtful Accounts (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of period	$ 89	$ 122	$ 90	$ 118
Provision charged to operations	4	1	8	11
Accounts written off, net of recoveries	(4)	(9)	(9)	(18)
Effect of exchange rate changes and other	(1)	0	(1)	3
Balance at end of period	$ 88	$ 114	$ 88	$ 114