Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions |
Sep. 30, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Receivables, allowance for doubtful accounts | $ 111 | $ 101 |
| Preferred stock, par (in dollars per share) | $ 1 | $ 1 |
| Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
| Preferred stock, shares issued | 0 | 0 |
| Common stock, par (in dollars per share) | $ 0.1667 | $ 0.1667 |
| Common stock, shares authorized | 300,000,000 | 300,000,000 |
| Common stock, shares issued | 198,406,586 | 198,372,059 |
| Treasury stock, shares | 49,305,407 | 50,084,043 |