Condensed Consolidated Balance Sheets (Parentheticals) (USD $) In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Allowance for doubtful accounts	$ 10.7	$ 10.8
Stockholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	50,000,000us-gaap_CommonStockSharesAuthorized	50,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	25,957,131us-gaap_CommonStockSharesIssued	25,847,269us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	23,141,080us-gaap_CommonStockSharesOutstanding	23,080,110us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	2,816,051us-gaap_TreasuryStockShares	2,767,159us-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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