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Share Capital (Dividends) (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2020 $ / shares | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Disclosure of share capital, reserves and other equity interest [Abstract] |  |  |
Increase in Share Price | $ 0.01 |  |
Increase In Share Price, Second | $ 0.02 |  |
Dividends paid, ordinary shares | $ |  | $ 25.6 | $ 23.9

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