Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Reserves on receivables	$ 20	$ 22
Accumulated depreciation	$ 1,926	$ 1,885
Preferred stock - par value	$ 1	$ 1
Preferred stock - authorized shares	36,000,000	36,000,000
Preferred stock - outstanding shares	0	0
Common stock - par value	$ 0.10	$ 0.10
Common stock - authorized shares	200,000,000	200,000,000
Common stock - issued shares	145,570,000	144,768,000
Treasury stock - shares	121,000,000	0