Financial Instruments and Risk Management (Credit Risk) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about financial instruments [line items]
Total financial instrument exposure to credit risk	$ 204.8	$ 258.1
Cash and Cash Equivalents [Member]
Disclosure of detailed information about financial instruments [line items]
Total financial instrument exposure to credit risk	200.8	252.2
Trade receivables [member]
Disclosure of detailed information about financial instruments [line items]
Total financial instrument exposure to credit risk	$ 4.0	$ 5.9

The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 35K
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_35K_a&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_36_a&doctype=Standard&book=B
-URIDate 2017-03-09

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant