Share Capital (Fair Value Assumptions) (Details)		12 Months Ended
Nov. 23, 2017 USD ($) month	Dec. 31, 2017 USD ($) month shares	Dec. 31, 2016 CAD month shares
Disclosure of terms and conditions of share-based payment arrangement [line items]
Granted \| shares		578,490	1,620,000
Weighted average share price at grant date (CAD$)		$ 9.62	CAD 3.75
Expected dividend yield		0.70%	0.70%
Expected stock price volatility (based on historical volatility)		57.00%	49.00%
Weighted average per share fair value of stock options granted (CAD$)		$ 4.27	CAD 1.52
Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Risk-free rate		0.91%	0.32%
Expected life of option (months)		36	42
Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Risk-free rate		1.35%	0.92%
Expected life of option (months)		84	84
Richmont Mines Ltd [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average share price at grant date (CAD$) \| $	$ 3.53
Risk-free rate	1.43%
Expected dividend yield	0.70%
Expected stock price volatility (based on historical volatility)	53.00%
Expected life of option (months)	12
Weighted average per share fair value of stock options granted (CAD$) \| $	$ 5.45

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
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-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_a_i&doctype=Standard
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The option life of share options granted.

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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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.

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No definition available.

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The percentage of an expected dividend used to calculate the fair value of share options granted.

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The number of share options granted in a share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
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The weighted average fair value of share options granted during the period at the measurement date. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Number 2
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The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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