XML 95 R64.htm IDEA: XBRL DOCUMENT v3.8.0.1

Share capital (Schedule of Fair Value Weighted-average Assumptions) (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2017 USD ($) yr	Dec. 31, 2016 USD ($) yr
Disclosure of classes of share capital [abstract]
Expected stock price volatility	[1]	83.00%	83.00%
Risk free interest rate		0.87%	0.47%
Expected life | yr		3	3
Expected forfeiture rate		4.18%	4.97%
Expected dividend yield		0.00%	0.00%
Share-based payments included in cost of sales			$ 19
Share-based payments included in general and administrative expenses		1,491	566
Total share-based payments		$ 1,491	$ 585
[1] Expected volatility has been based on historical volatility of the Company's publicly traded shares.

X

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DescriptionOfExpectedVolatilityShareOptionsGranted
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The option life of share options granted.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DescriptionOfOptionLifeShareOptionsGranted
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_DescriptionOfRiskFreeInterestRateShareOptionsGranted
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfClassesOfShareCapitalAbstract
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2017-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=2&date=2017-03-01&anchor=para_47_a_i&doctype=Standard
-URIDate 2017-03-09

+ Details

Name:	ifrs-full_ExpectedDividendAsPercentageShareOptionsGranted
Namespace Prefix:	ifrs-full_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

+ References

No definition available.

+ Details

Name:	usas_ExpectedForfeitureRateAsPercentageShareOptionsGranted
Namespace Prefix:	usas_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Increase (Decrease) Through Share-based Payment Transactions Cost of Sales

+ References

No definition available.

+ Details

Name:	usas_IncreaseDecreaseThroughSharebasedPaymentTransactionsCostOfSales
Namespace Prefix:	usas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Increase (Decrease) Through Share-based Payment Transactions General and Administrative

+ References

No definition available.

+ Details

Name:	usas_IncreaseDecreaseThroughSharebasedPaymentTransactionsGeneralAndAdministrative
Namespace Prefix:	usas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Total share-based payments of stock-options.

+ References

No definition available.

+ Details

Name:	usas_TotalShareBasedPaymentsStockOptions
Namespace Prefix:	usas_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration