CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions |
Dec. 31, 2014 |
Sep. 30, 2014 |
Jun. 30, 2014 |
Mar. 31, 2014 |
Dec. 31, 2013 |
Sep. 30, 2013 |
Jun. 30, 2013 |
Mar. 31, 2013 |
Dec. 31, 2012 |
|---|---|---|---|---|---|---|---|---|---|
| Statement of Financial Position [Abstract] | |||||||||
| Receivables, allowance for doubtful accounts (in dollars) | $ 67 | $ 66 | $ 70 | $ 69 | $ 62 | $ 67 | $ 56 | $ 58 | $ 53 |
| Preferred Stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 |
| Preferred Stock, shares authorized | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 | 200,000,000 |
| Preferred Stock, shares issued | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Preferred Stock, shares outstanding | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Common Stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01 |
| Common Stock, shares authorized | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 | 2,000,000,000 |
| Common Stock, shares issued | 463,000,000 | 463,000,000 | 463,000,000 | 452,000,000 | 450,000,000 | 449,000,000 | 425,000,000 | 423,000,000 | 422,000,000 |
| Common Stock, shares outstanding | 459,000,000 | 459,000,000 | 459,000,000 | 448,000,000 | 446,000,000 | 421,000,000 | 401,000,000 | 400,000,000 | 422,000,000 |
| Treasury stock, shares | 4,000,000 | 4,000,000 | 4,000,000 | 4,000,000 | 4,000,000 | 0 | 23,000,000 | 23,000,000 | 0 |