Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 2.3	$ 2.4
Properties and equipment, accumulated depreciation	127.5	125.5
Rental equipment, accumulated depreciation	34.6	33.6
Intangible assets, accumulated amortization	$ 24.5	$ 22.1
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized	90,000,000	90,000,000
Common stock, shares issued	67,200,000	66,900,000
Treasury stock, shares	7,000,000	6,400,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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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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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

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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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