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Foreign Operations | 12 Months Ended
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Dec. 31, 2014
Concentration Risks, Types, No Concentration Percentage [Abstract] |
Foreign Operations | For the years ended December 31, 2014, 2013, and 2012, we did not derive revenues in excess of 10% of our consolidated revenues from any one foreign country. Additionally, at December 31, 2014 and 2013, we did not have more than 10% of our identifiable assets in any one foreign country. The following table shows our domestic and foreign revenues and identifiable assets for the years ending or as of December 31 (in millions):
| 2014 |  | 2013 |  | 2012
Revenues |  |  |  |  |
Foreign | $ | 346.2 |  |  | $ | 332.1 |  |  | $ | 279.8 |
United States | 1,104.8 |  |  | 988.9 |  |  | 963.4 |
| $ | 1,451.0 |  |  | $ | 1,321.0 |  |  | $ | 1,243.2 |
Identifiable Assets |  |  |  |  |
Foreign | $ | 2,133.9 |  |  | $ | 2,200.1 |  |  | $ | 1,897.9 |
United States | 4,803.6 |  |  | 4,349.5 |  |  | 4,157.5 |
| $ | 6,937.5 |  |  | $ | 6,549.6 |  |  | $ | 6,055.4 |

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