Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Statement of Financial Position
Preferred Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred Stock, shares authorized (in shares)	100,000	100,000
Preferred Stock, shares issued (in shares)	0	0
Preferred Stock, shares outstanding (in shares)	0	0
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	3,200,000,000	3,200,000,000
Common Stock, shares issued (in shares)	1,707,000,000	1,705,000,000
Common Stock, shares outstanding (in shares)	1,027,000,000	1,061,000,000
Treasury Stock, shares (in shares)	679,000,000	643,000,000
Shares held in trust: 1 share at December 31, 2016 and 2015 (in shares)	1,000,000	1,000,000