Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Balance Sheet Parentheticals [Abstract]
Allowances for receivables	$ 63	$ 50
Common Class A [Member]
Class of Stock [Line Items]
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized	375,000,000	375,000,000
Common Stock, shares issued	38,000,000	38,000,000
Common Class B [Member]
Class of Stock [Line Items]
Common Stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common Stock, shares authorized	5,000,000,000	5,000,000,000
Common Stock, shares issued	826,000,000	818,000,000
Treasury Stock, at cost, Class B Shares	401,000,000	349,000,000