Acquisitions Through Business Combinations, Share Based Compensation

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- Definition

Business Combination, Shares Issued, Value

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- Definition

Business Combinations, Conversion Ratio of Shares

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- Definition

Number of Shares Issued, Business Combination

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- Definition

The amount of acquisition-related costs for transactions recognised separately from the acquisition of assets and the assumption of liabilities in business combinations. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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No definition available.

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- Definition

The profit (loss) of the acquiree, since the acquisition date, included in the consolidated statement of comprehensive income. [Refer: Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The profit (loss) of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Profit (loss)]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of revenue of the acquiree since the acquisition date included in the consolidated statement of comprehensive income. [Refer: Revenue]

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- Definition

The revenue of the combined entity as though the acquisition date for all business combinations that occurred during the year had been as of the beginning of the annual reporting period. [Refer: Business combinations [member]; Revenue]

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Acquisition of Richmond Mines Ltd. (Narrative) (Details) - Richmont Mines Ltd [Member] $ in Millions		1 Months Ended	12 Months Ended
	Nov. 23, 2017 USD ($) shares	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Disclosure of detailed information about business combination [line items]
Conversion of Richmont units to Alamos units (note 5) \| shares	88,398,804
Number of shares issued, business combination, value	$ 615.3
Transaction costs	3.8
Share based compensation, acquisitions	$ 12.1
Revenue of acquiree since acquisition date		$ 14.9
Profit of acquiree since acquisition date		$ 1.5
Revenue of combined entity as if combination occurred at beginning of period			$ 125.3
Profit (loss) of combined entity as if combination occurred at beginning of period			$ 12.0
Ordinary shares [member]
Disclosure of detailed information about business combination [line items]
Conversion ratio of shares	1.385
Other Loss [Member]
Disclosure of detailed information about business combination [line items]
Share based compensation, acquisitions	$ 1.3