Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4.1	$ 3.7
Capital stock, par value (in dollars per share)	$ 1	$ 1
Serial preferred stock, shares authorized (in shares)	632,470us-gaap_PreferredStockSharesAuthorized	632,470us-gaap_PreferredStockSharesAuthorized
Serial preferred stock, shares issued (in shares)	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Serial preferred stock, shares outstanding (in shares)	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, shares authorized (in shares)	40,000,000us-gaap_CommonStockSharesAuthorized	40,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued (in shares)	14,513,821us-gaap_CommonStockSharesIssued	14,364,239us-gaap_CommonStockSharesIssued
Treasury stock, shares (in shares)	2,014,692us-gaap_TreasuryStockShares	1,934,959us-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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Face amount or stated value per share of common stock.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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