Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Millions, $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 2.8	$ 2.9
Properties and equipment, accumulated depreciation	144.2	136.2
Rental equipment, accumulated depreciation	42.8	43.5
Intangible assets, accumulated amortization	$ 37.2	$ 31.9
Common stock, par value (usd per share)	$ 1
Common stock, shares authorized	90.0
Common stock, shares issued	68.7	67.8
Treasury stock, shares	7.5	7.3

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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Amount of allowance for credit loss on accounts receivable, classified as current.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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