Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Allowance for doubtful accounts	$ 103.1	$ 111.4
OTHER ASSETS:
Accumulated amortization on intangible assets	$ 241.4	$ 276.2
SHAREHOLDERS' EQUITY:
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	25,000,000us-gaap_PreferredStockSharesAuthorized	25,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	125,000,000us-gaap_CommonStockSharesAuthorized	125,000,000us-gaap_CommonStockSharesAuthorized
Common stock, issued (in shares)	113,459,451us-gaap_CommonStockSharesIssued	112,876,552us-gaap_CommonStockSharesIssued
Treasury stock at cost (in shares)	35,353,512us-gaap_TreasuryStockShares	34,762,316us-gaap_TreasuryStockShares

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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