Future Minimum Lease Payments (Details) $ in Millions	Dec. 31, 2015 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Rent Obligations, due 2016	$ 322.0
Rent Obligations, due 2017	300.4
Rent Obligations, due 2018	272.2
Rent Obligations, due 2019	246.1
Rent Obligations, due 2020	224.5
Rent Obligations, due thereafter	909.0
Total Rent Obligations	2,274.2
Sublease Rental Income, due 2016	(4.4)
Sublease Rental Income, due 2017	(1.9)
Sublease Rental Income, due 2018	(0.8)
Sublease Rental Income, due 2019	(0.7)
Sublease Rental Income, due 2020	0.0
Sublease Rental Income, due thereafter	0.0
Total Sublease Rental Income	(7.8)
Net Rent, due 2016	317.6
Net Rent, due 2017	298.5
Net Rent, due 2018	271.4
Net Rent, due 2019	245.4
Net Rent, due 2020	224.5
Net Rent, due thereafter	909.0
Total Net Rent	$ 2,266.4

Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals, Current

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

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Contractually required future rental payments receivable on noncancelable subleasing arrangements.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in 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.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after 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.

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