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Commitments and Contingencies (Future Minimum Rental Commitments) (Details) $ in Millions | Dec. 31, 2017 USD ($)
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2018- Capital Leases | $ 2.3
2019- Capital Leases | 0.1
2020- Capital Leases | 0.0
2021- Capital Leases | 0.0
2022- Capital Leases | 0.0
After 2022- Capital Leases | 0.0
Total minimum payment required- Capital Leases | 2.4
2018- Operating Leases | 10.0
2019- Operating Leases | 7.5
2020- Operating Leases | 6.0
2021- Operating Leases | 3.7
2022- Operating Leases | 2.1
After 2022- Operating Leases | 2.6
Total minimum payment required- Operating Leases | 31.9
2018- Total Leases | 12.3
2019- Total Leases | 7.6
2020- Total Leases | 6.0
2021- Total Leases | 3.7
2022- Total Leases | 2.1
After 2022- Total Leases | 2.6
Total minimum payment required | $ 34.3

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