Other Liabilities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Other Liabilities Disclosure [Abstract]
Compensation and benefits	$ 94.4	$ 123.3
Accrued bonus and deferred compensation	572.9	553.1
Accrued compensation and benefits	667.3	676.4
Accruals and other liabilities	260.6us-gaap_OtherLiabilities	248.6us-gaap_OtherLiabilities
Deferred Revenue	54.8us-gaap_DeferredRevenue	8.3us-gaap_DeferredRevenue
Overdraft on unsettled fund account	0us-gaap_BankOverdrafts	35.7us-gaap_BankOverdrafts
Accounts payable	343.5	334.6
Security deposit payables	3.2us-gaap_SecurityDepositLiability	12.3us-gaap_SecurityDepositLiability
Income taxes payable	95.2us-gaap_AccruedIncomeTaxes	123.6us-gaap_AccruedIncomeTaxes
Accounts payable and accrued expenses	$ 757.3	$ 763.1

Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.

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Carrying value as of the balance sheet date of obligations incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them.

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due. This amount is the total of current and noncurrent accrued income taxes.

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Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

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-Glossary Current Liabilities

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Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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This element represents money paid in advance to protect the provider of a product or service, such as a lessor, against damage or nonpayment by the buyer or tenant (lessee) during the term of the agreement. Such damages may include physical damage to the property, theft of property, and other contractual breaches. Security deposits held may be interest or noninterest bearing.

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