XML 159 R136.htm IDEA: XBRL DOCUMENT
v3.21.1

Note 30 - Share-based payments - Inputs for Measurement of Grant Date Fair Values and Share Units Granted (Details) |  | 12 Months Ended
--- | --- | ---
Feb. 27, 2018 USD ($) $ / shares | Dec. 31, 2020 USD ($) $ / shares | Dec. 31, 2019 USD ($) $ / shares
Statement Line Items [Line Items] |  |  |
Options Granted | 10,000 |  |
Risk-free interest rate | 2.86% |  |
Expected stock price volatility (based on historical volatility) | 32.00% |  |
Expected option life in years | 3 |  |
Exercise price (in CAD per share) | $ 9.30 |  |
Share price at grant date (in CAD per share) | $ 9.30 |  |
Fair value at grant date | $ | $ 1.40 |  |
Restricted stock units (RSUs) [member] |  |  |
Statement Line Items [Line Items] |  |  |
Fair value (USD) | $ |  | $ 15.88 | $ 8.46
Share price (USD) (in dollars per share) |  | $ 15.88 | $ 8.46
RSU dividends reinvested |  | 995 | 11,316
Awards paid out/ expired |  | (5,052) | (87,434)
Total awards outstanding |  | 17,971 | 5,052
Restricted stock units (RSUs) [member] | January 11, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 60,645
Restricted stock units (RSUs) [member] | March 23, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 10,965
Restricted stock units (RSUs) [member] | June 8, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 5,117
Restricted stock units (RSUs) [member] | January 19, 2017 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 4,443 | 4,443
Restricted stock units (RSUs) [member] | January 11, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | March 23, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | June 8, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | January 11, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 17,585 |
Restricted stock units (RSUs) [member] | March 31, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | June 1, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | September 9, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | September 14, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Restricted stock units (RSUs) [member] | October 5, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  |
Performance share units (PSUs) [member] |  |  |
Statement Line Items [Line Items] |  |  |
Fair value (USD) | $ |  | $ 15.51 | $ 8.19
Share price (USD) (in dollars per share) |  | $ 15.88 | $ 8.46
RSU dividends reinvested |  |  |
Awards paid out/ expired |  | (17,774) | (306,920)
Total awards outstanding |  | 279,889 | 156,473
Performance share units (PSUs) [member] | January 11, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 242,579
Performance share units (PSUs) [member] | March 23, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 43,871
Performance share units (PSUs) [member] | June 8, 2016 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  |  | 20,470
Performance share units (PSUs) [member] | January 19, 2017 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 17,774 | 17,774
Performance share units (PSUs) [member] | January 11, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 95,740 | 95,740
Performance share units (PSUs) [member] | March 23, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 28,287 | 28,287
Performance share units (PSUs) [member] | June 8, 2019 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 14,672 | 14,672
Performance share units (PSUs) [member] | January 11, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 114,668 |
Performance share units (PSUs) [member] | March 31, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 1,971 |
Performance share units (PSUs) [member] | June 1, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 1,740 |
Performance share units (PSUs) [member] | September 9, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 1,611 |
Performance share units (PSUs) [member] | September 14, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 20,686 |
Performance share units (PSUs) [member] | October 5, 2020 [member] |  |  |
Statement Line Items [Line Items] |  |  |
Grants |  | 514 |
Performance share units (PSUs) [member] | Bottom of range [member] |  |  |
Statement Line Items [Line Items] |  |  |
Performance multiplier percentage |  | 93.00% | 93.00%
Performance share units (PSUs) [member] | Top of range [member] |  |  |
Statement Line Items [Line Items] |  |  |
Performance multiplier percentage |  | 100.00% | 100.00%

X
- Definition The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement as a result of dividends being re-invested. + References No definition available. + Details
Name: | cmcl_NumberOfOtherEquityInstrumentsGrantedInSharebasedPaymentArrangementFromDividends
Namespace Prefix: | cmcl_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The performance multiplier if performance conditions have been met. + References No definition available. + Details
Name: | cmcl_PerformanceMultiplier
Namespace Prefix: | cmcl_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | cmcl_StatementLineItems
Namespace Prefix: | cmcl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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 2020-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2020-01-01 + 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 2020-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2020-01-01 + 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 2020-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_DescriptionOfRiskFreeInterestRateShareOptionsGranted
Namespace Prefix: | ifrs-full_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The exercise price of share options granted. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_ExercisePriceShareOptionsGranted2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_NumberOfInstrumentsOtherEquityInstrumentsGranted
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of share options granted in a share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_ii&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_NumberOfShareOptionsGrantedInSharebasedPaymentArrangement
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

X
- Definition The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph b -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_b&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_WeightedAverageFairValueAtMeasurementDateOtherEquityInstrumentsGranted
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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 -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_WeightedAverageFairValueAtMeasurementDateShareOptionsGranted
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The weighted average share price. [Refer: Weighted average [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 45 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_c&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_WeightedAverageSharePrice2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition 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]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 2 -IssueDate 2020-01-01 -Paragraph 47 -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard -URIDate 2020-01-01 + Details
Name: | ifrs-full_WeightedAverageSharePriceShareOptionsGranted2019
Namespace Prefix: | ifrs-full_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=cmcl_RestrictedStockUnitsRsusMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_January112016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_March232016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_June82016Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_January192017Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_January112019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_March232019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_June82019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_January112020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_March312020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_June12020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_September92020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_September142020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_CreationDateAxis=cmcl_October52020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=cmcl_PerformanceShareUnitsPsusMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |