| **Property and Equipment - Fully Depreciated Assets and Assets Under Capital Lease (Details) - USD ($) $ in Millions** | Dec. 31, 2016 | Dec. 31, 2015 |
|------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Property, Plant and Equipment [Line Items]**                                                                         |          |          |
| Fully depreciated assets                                                                                               | $ 289.7       | $ 252.4       |
| **Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]**                                               |          |          |
| Capital Leased Assets, Gross                                                                                           | 339.9         | 340.7         |
| Accumumlated Amortization                                                                                              | (83.5)        | (66.6)        |
| Assets Under Capital Lease Obligations, Net                                                                            | 256.4         | 274.1         |
| Building [Member]                                                                                                      |          |          |
| **Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]**                                               |          |          |
| Capital Leased Assets, Gross                                                                                           | 331.0         | 333.9         |
| Vehicles [Member]                                                                                                      |          |          |
| **Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]**                                               |          |          |
| Capital Leased Assets, Gross                                                                                           | 8.6           | 6.5           |
| Equipment [Member]                                                                                                     |          |          |
| **Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]**                                               |          |          |
| Capital Leased Assets, Gross                                                                                           | $ 0.3         | $ 0.3         |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Original cost, at the balance sheet date, of long lived physical assets used in the normal conduct of business and not intended for resale that are fully depreciated but still in service. This can include buildings and improvements, machinery and equipment, and other types of furniture and equipment.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737
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| X                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 2) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697
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| X                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------|
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