Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Allowance for doubtful accounts receivable, current	$ 1.4	$ 1.1
Accumulated depreciation, properties and equipment	116.6	108.9
Accumulated depreciation, rental equipment	26.9	20.0
Accumulated amortization, intangible assets	$ 11.5	$ 5.5
Common stock, par value (usd per share)	$ 1	$ 1
Common stock, shares authorized (shares)	90,000,000	90,000,000
Common stock, shares issued (shares)	66,300,000	66,100,000
Treasury stock, shares (shares)	6,100,000	6,100,000

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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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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