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Supplemental Cash Flow Data (Tables) | 12 Months Ended
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Dec. 31, 2017
Supplemental Cash Flow Data [Abstract] |
Change in Operating Capital | The increase in operating capital for the three years ended December 31, 2017 was (in millions):
| 2017 |  | 2016 |  | 2015
(Increase) decrease in accounts receivable | $ | (341.6 | ) |  | $ | (376.5 | ) |  | $ | (1,063.6 | )
(Increase) decrease in work in process and other current assets | 5.4 |  |  | (89.7 | ) |  | (79.6 | )
Increase (decrease) in accounts payable | 763.2 |  |  | 741.9 |  |  | 1,443.7 |
Increase (decrease) in customer advances, taxes payable and other current liabilities | 4.8 |  |  | 31.6 |  |  | 243.9 |
Change in other assets and liabilities, net | (83.3 | ) |  | (4.5 | ) |  | 15.1 |
| $ | 348.5 |  |  | $ | 302.8 |  |  | $ | 559.5 |
Income taxes paid | $ | 566.0 |  |  | $ | 570.4 |  |  | $ | 540.1 |
Interest paid | $ | 226.2 |  |  | $ | 216.7 |  |  | $ | 173.9 |

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