| **Property and Equipment (Tables)**                                                                                                                          | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Property, Plant and Equipment [Abstract]**                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Components of Property and Equipment                                                                                                                         | Property and equipment consists of the following (in millions): As of December 31, 2014 2013Land$108.1 $96.0Buildings1,214.4 1,085.2Leasehold improvements79.1 65.0Vehicles9.3 4.8Furniture, fixtures, and equipment364.2 339.6 1,775.1 1,590.6Less: Accumulated depreciation and amortization(784.0) (712.6) 991.1 878.0Construction in progress28.6 32.5Property and equipment, net$1,019.7 $910.5                                                                                                                                                                                                     |
| Fully Depreciated Assets and Assets Under Capital Lease Obligations                                                                                          | Information related to fully depreciated assets and assets under capital lease obligations is as follows (in millions): As of December 31, 2014 2013Fully depreciated assets$240.9 $225.0Assets under capital lease obligations:   Buildings$124.4 $124.4Vehicles5.2 —Equipment0.2 0.2 129.8 124.6Less: Accumulated amortization(55.2) (47.6)Assets under capital lease obligations, net$74.6 $77.0                                                                                                                                                                                                     |
| Depreciation Expense, Amortization Expense Relating to Assets Under Capital Lease Obligations, Interest Capitalized, and Rent Expense Under Operating Leases | The amount of depreciation expense, amortization expense relating to assets under capital lease obligations, interest capitalized, and rent expense under operating leases is as follows (in millions): For the Year Ended December 31, 2014 2013 2012Depreciation expense$79.9 $67.9 $59.0Amortization expense$7.5 $9.5 $10.1Interest capitalized$1.5 $1.9 $1.0Rent expense:     Minimum rent payments$37.3 $40.3 $41.2Contingent and other rents18.2 20.3 20.6Other3.9 4.2 4.5Total rent expense$59.4 $64.8 $66.3                                              |
| Schedule of Accrued Straight-Line Rent                                                                                                                       | The excess of cumulative rent expense (recognized on a straight-line basis) over cumulative rent payments made on leases with fixed escalation terms is recognized as straight-line rental accrual and is included in Other long-term liabilities in the accompanying consolidated balance sheets, as follows (in millions): As of December 31, 2014 2013Straight-line rental accrual$14.6 $17.3                                                                                                                                                                                                                                                                |
| Schedule of Future Minimum Lease Payments                                                                                                                    | Future minimum lease payments at December 31, 2014, for those leases having an initial or remaining noncancelable lease term in excess of one year, are as follows (in millions):Year Ending December 31, Operating Leases Capital Lease Obligations Total2015 $43.8 $15.3 $59.12016 37.6 15.0 52.62017 31.8 14.0 45.82018 27.0 13.6 40.62019 22.4 10.7 33.12020 and thereafter 87.3 98.4 185.7  $249.9 167.0 $416.9Less: Interest portion   (80.3)  Obligations under capital leases   $86.7   |

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Tabular disclosure of fully depreciated assets and assets under capital lease obligations.
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No definition available.
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Tabular disclosure describing the components that make up the Company's total property and equipment.
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No definition available.
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| - Definition
Tabular disclosure of the Company's liability for straight-line rent. The excess of cumulative rent expense (recognized on a straight-line basis) over cumulative rent payments made on leases with fixed excalation terms is recognized as straight-line rental accrual.
+ References
No definition available.
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| - Definition
Tabular disclosure of depreciation expense, amortization expense relating to assets under capital lease obligations, interest capitalized, and rent expense under operating leases.
+ References
No definition available.
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| - Definition
Tabular disclosure of future minimum lease payments for those leases (operating and capital) having an initial or remaining non-cancelable lease term in excess of one year.
+ References
No definition available.
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