Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Receivables, allowances	$ 119.6	$ 117.4
Ordinary shares, par value (in dollars)	$ 1.00	$ 1
Ordinary shares, shares authorized (in shares)	618,300,000.0	525,000,000
Common Stock, Value, Issued	$ 450.5	$ 465.1
Common Stock, Shares, Issued		465,100,000
Ordinary shares, shares outstanding (in shares)	450,500,000	465,100,000
Canceled shares (in shares)	14,800,000	2,100,000
Ordinary shares, held in employee benefit trust (in shares)	100,000	100,000
Treasury stock, at cost (in shares)		300,000

Common Stock, Shares Cancelled

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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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Number of common stock held in a trust that has been set up specifically to accumulate stock for the sole purpose of distribution to participating employees but not yet earned.

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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 shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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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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