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Share Capital (Share Capital) (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Feb. 09, 2017 | Dec. 31, 2017 | Dec. 31, 2016
Reconciliation of number of shares outstanding [abstract] |  |  |
Beginning balance |  | $ 1,759.4 |
Shares issued through: |  |  |
Equity financing (in shares) | 31,450,000 |  |
Ending balance |  | $ 2,681.2 | $ 1,759.4
Issued capital [member] |  |  |
Reconciliation of number of shares outstanding [abstract] |  |  |
Number of shares outstanding |  | 267,076,495.000 | 257,070,005
Beginning balance |  | $ 2,822.2 | $ 2,773.7
Shares issued through: |  |  |
Acquisitions (in shares) |  |  | 4,788,039
Acquisitions |  | $ 0.0 | $ 17.5
Acquisitions (shares) |  | 88,398,804 |
Acquisitions |  | $ 615.3 | $ 0.0
Equity financing (in shares) |  | 31,450,000 |
Equity financing |  | $ 241.8 |
Share-based employment compensation plans (in shares) |  | 542,250.0 | 1,457,872
Share-based compensation plans |  | $ 3.5 | $ 9.7
Exercise of warrants (in shares) |  | 332,466.0 | 432,191
Exercise of warrants |  | $ 0.5 | $ 1.2
Flow-through share financing (in shares) |  | 1,301,535 | 3,328,388.0
Flow-through share financing |  | $ 8.4 | $ 20.1
Number of shares outstanding |  | 389,101,550.00 | 267,076,495.000
Ending balance |  | $ 3,691.7 | $ 2,822.2

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