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Financial Instruments and Risk Management (Fuel Option Contracts) (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Disclosure of detailed information about hedged items [line items]
Gains (losses) on change in fair value of derivatives	$ 100
Fuel Options [Member] | Commodity price risk [member]
Disclosure of detailed information about hedged items [line items]
Derivative, notional amount		$ 2,740
Gains (losses) on change in fair value of derivatives		$ (500)
Bottom of range [member] | Fuel Options [Member] | Commodity price risk [member]
Disclosure of detailed information about hedged items [line items]
Average price of hedging instrument		1.83
Top of range [member] | Fuel Options [Member] | Commodity price risk [member]
Disclosure of detailed information about hedged items [line items]
Average price of hedging instrument		2.09

X

- Definition

The average price of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 23B
-Subparagraph b
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-URIDate 2018-03-16

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 85
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_85&doctype=Standard
-URIDate 2018-03-16

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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