| **Property and Equipment (Tables)**                                                                                                                          | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Property, Plant and Equipment [Abstract]**                                                                                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Components of Property and Equipment                                                                                                                         | Useful lives are generally as follows: YearsBuildings10 to 30Leasehold improvements2 to 15Vehicles5Furniture, fixtures, and equipment2 to 10Assets under capital lease obligations: Real estate15 to 25Vehicles3Equipment3 to 5Property and equipment consists of the following (in millions): As of December 31, 2016 2015Land$125.3 $113.3Buildings1,601.4 1,521.1Leasehold improvements115.2 96.2Vehicles11.8 10.0Furniture, fixtures, and equipment425.3 392.7 2,279.0 2,133.3Less: Accumulated depreciation and amortization(982.4) (874.3) 1,296.6 1,259.0Construction in progress95.2 51.1Property and equipment, net$1,391.8 $1,310.1 |
| 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, 2016 2015Fully depreciated assets$289.7 $252.4Assets under capital lease obligations:   Buildings$331.0 $333.9Vehicles8.6 6.5Equipment0.3 0.3 339.9 340.7Less: Accumulated amortization(83.5) (66.6)Assets under capital lease obligations, net$256.4 $274.1                                                                                                                                                                                                                                                      |
| 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, 2016 2015 2014Depreciation expense$102.3 $91.0 $79.9Amortization expense$21.8 $12.7 $7.5Interest capitalized$2.0 $1.3 $1.5Rent expense:     Minimum rent payments$62.6 $48.8 $37.3Contingent and other rents29.4 21.6 18.2Other4.0 3.8 3.9Total rent expense$96.0 $74.2 $59.4                                                                                           |
| 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, 2016 2015Straight-line rental accrual$11.8 $12.4                                                                                                                                                                                                                                                                                                               |
| Schedule of Future Minimum Capital Lease Payments                                                                                                            | Future minimum lease payments at December 31, 2016, 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 Total2017 $62.5 $34.7 $97.22018 56.9 34.9 91.82019 51.4 31.0 82.42020 42.6 27.8 70.42021 32.8 28.4 61.22022 and thereafter 173.8 356.5 530.3  $420.0 513.3 $933.3Less: Interest portion   (234.0)  Obligations under capital leases   $279.3                                              |
| Schedule of Future Minimum Operating Lease Payments                                                                                                          | Future minimum lease payments at December 31, 2016, 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 Total2017 $62.5 $34.7 $97.22018 56.9 34.9 91.82019 51.4 31.0 82.42020 42.6 27.8 70.42021 32.8 28.4 61.22022 and thereafter 173.8 356.5 530.3  $420.0 513.3 $933.3Less: Interest portion   (234.0)  Obligations under capital leases   $279.3                                              |

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| - Definition
Tabular disclosure of fully depreciated assets and assets under capital lease obligations.
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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.
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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.
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No definition available.
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| - Definition
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
+ References
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| - Definition
Tabular disclosure of future minimum lease payments as of the date of the latest balance sheet presented, in aggregate and for each of the five years succeeding fiscal years, with separate deductions from the total for the amount representing executor costs, including any profit thereon, included in the minimum lease payments and for the amount of the imputed interest necessary to reduce the net minimum lease payments to present value.
+ References
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| - Definition
Tabular disclosure of future minimum payments required in the aggregate and for each of the five succeeding fiscal years for operating leases having initial or remaining noncancelable lease terms in excess of one year and the total minimum rentals to be received in the future under noncancelable subleases as of the balance sheet date.
+ References
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