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v3.19.1

Management of Capital (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Disclosure of objectives, policies and processes for managing capital [abstract] |  |
Shareholder's equity | $ 2,602.3 | $ 2,681.2
Managed capital | $ 2,602.3 | $ 2,681.2

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