Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Trade and other receivables, allowance	$ 58.4	$ 49.5
Ordinary shares, nominal value per share (in dollars per share)	$ 0.10	$ 0.1
Ordinary shares issued (in shares)	219,500,000.0	216,600,000.0
Ordinary shares outstanding (in shares)	219,500,000.0	216,600,000.0

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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