SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period,	$ 248	$ 261	$ 279
Provision Charged to Income	110	117	81
Deductions from reserves	(119)	(132)	(113)
Acquisitions	8	2	14
Balance at end of period,	247	248	261
Deferred Tax Assets Valuation Allowance [Member]
Valuation And Qualifying Accounts Disclosure [Line Items]
Provision Charged to Income	$ 103	$ 72	$ 109