| 
           Goodwill and Other Intangibles (Details 3) (USD $) 
        In Millions, unless otherwise specified  | 
        12 Months Ended | ||
|---|---|---|---|
| 
           Dec. 31, 2014 
         | 
        
           Dec. 31, 2013 
         | 
        
           Dec. 31, 2012 
         | 
      |
| Finite-Lived Intangible Assets [Line Items] | |||
| Gross Carrying Amount | $ 250.5us-gaap_FiniteLivedIntangibleAssetsGross | $ 241.6us-gaap_FiniteLivedIntangibleAssetsGross | |
| Accumulated Amortization | (236.5)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization | (234.4)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization | |
| Amortization expense for intangibles | 2.9us-gaap_AmortizationOfIntangibleAssets | 2.7us-gaap_AmortizationOfIntangibleAssets | 4.1us-gaap_AmortizationOfIntangibleAssets | 
| Finite-Lived Intangible Assets, Future Amortization Expense [Abstract] | |||
| 2015 | 3us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths | ||
| 2016 | 2us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo | ||
| 2017 | 2us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree | ||
| 2018 | 2us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour | ||
| 2019 | 1us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive | ||
| Customer relationships [Member] | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Gross Carrying Amount | 
234.8us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember  | 
        
227.6us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember  | 
        |
| Accumulated Amortization | 
(223.5)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember  | 
        
(221.4)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_CustomerRelationshipsMember  | 
        |
| Other Intangible Assets [Member] | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Gross Carrying Amount | 
15.7us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_OtherIntangibleAssetsMember  | 
        
14.0us-gaap_FiniteLivedIntangibleAssetsGross / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_OtherIntangibleAssetsMember  | 
        |
| Accumulated Amortization | 
$ (13.0)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_OtherIntangibleAssetsMember  | 
        
$ (13.0)us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization / us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis = us-gaap_OtherIntangibleAssetsMember  | 
        |
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- Definition 
          The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 
          Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
          
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- Definition 
          Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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