Other Financial Data Schedule of Allowance for Doubtful Accounts (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of year	$ 118	$ 104	$ 102	$ 90
Provision charged to operations	9	45	43
Accounts written off, net of recoveries	(38)	(30)	(42)
Effect of exchange rate changes and other	1	(1)	1
Balance at end of year	$ 90	$ 118