XML 182 R159.htm IDEA: XBRL DOCUMENT
v3.23.1

Financial Risk Management And Fair Values Of Financial Instruments - Summary of Effect of Profit or Loss or of Other Comprehensive Income from Financial Assets Categorized (Detail) - Financial instruments at fair value through other comprehensive income [member] - TWD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Favorable Changes | $ 6,866 | $ 8,074
Unfavorable Changes In Fair Value | 6,922 | 8,074
Enter prise value EBITDA multiple [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Favorable Changes |  | 3,443
Unfavorable Changes In Fair Value |  | 3,443
Discount for lack of marketability [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Favorable Changes | 3,990 | 4,585
Unfavorable Changes In Fair Value | 4,039 | 4,585
Foreign unlisted stocks [member] | Price to book ratio multiple [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Favorable Changes |  | 46
Unfavorable Changes In Fair Value |  | $ 46
Foreign unlisted stocks [member] | Enter prise value EBITDA multiple [member] |  |
Disclosure of significant unobservable inputs used in fair value measurement of equity [line items] |  |
Favorable Changes | 2,876 |
Unfavorable Changes In Fair Value | $ 2,883 |

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfSignificantUnobservableInputsUsedInFairValueMeasurementOfEquityLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Favorable changes in fair value. + References No definition available. + Details
Name: | imos_FavorableChangesInFairValue
Namespace Prefix: | imos_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Unfavorable changes in fair value. + References No definition available. + Details
Name: | imos_UnfavorableChangesInFairValue
Namespace Prefix: | imos_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ifrs-full_CategoriesOfFinancialAssetsAxis=imos_FinancialInstrumentsAtFairValueThroughOtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ValuationTechniquesUsedInFairValueMeasurementAxis=imos_EnterPriseValueEBITDAMultipleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ValuationTechniquesUsedInFairValueMeasurementAxis=imos_DiscountForLackOfMarketabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ClassesOfFinancialInstrumentsAxis=imos_ForeignUnlistedStocksMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | ifrs-full_ValuationTechniquesUsedInFairValueMeasurementAxis=imos_PriceBookValueMultipleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |