CONDENSED CONSOLIDATED BALANCE SHEETS - Parenthetical - USD ($) shares in Millions, $ in Millions	Jul. 31, 2019	Jan. 31, 2019
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable - trade, allowance for doubtful accounts	$ 4.9	$ 3.1
Property and equipment, accumulated depreciation	$ 178.5	$ 152.7
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	110.0	110.0
Common stock, shares issued	23.6	22.6
Treasury stock	0.1	0.0

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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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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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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