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Supplemental Financial Statement Information (Tables) | 12 Months Ended
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Dec. 31, 2017
Additional Financial Information Disclosure [Abstract] |
Schedule of cash and cash equivalents | Cash and cash equivalents at December 31, 2017 and 2016 were as follows:
(In millions) |  | 2017 |  | 2016
Cash |  | $ | 140.2 |  |  | $ | 164.1 |
Other short-term investments |  | 1.4 |  |  | 65.5 |
Total cash and cash equivalents |  | $ | 141.6 |  |  | $ | 229.6 |
Schedule of other non-operating income (expense) | Other income (expense) for the years ended December 31, 2017, 2016, and 2015 was as follows:
(In millions) |  | 2017 |  | 2016 |  | 2015
Rent and royalty income |  | $ | 3.5 |  |  | $ | 1.4 |  |  | $ | 2.0 |
Net gains on property and investments |  | 0.5 |  |  | 1.0 |  |  | — |
Other |  | — |  |  | — |  |  | (0.4 | )
Total other income, net |  | $ | 4.0 |  |  | $ | 2.4 |  |  | $ | 1.6 |

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- Definition Tabular disclosure of the components of non-operating income or non-operating expense that may include amounts earned from dividends, interest on securities, gains (losses) on securities sold, equity earnings of unconsolidated affiliates, net gain (loss) on sales of business, interest expense and other miscellaneous income or expense items. + References No definition available. + Details
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