XML 87 R64.htm IDEA: XBRL DOCUMENT
v3.23.1

Pensions (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2022
Text block [abstract] |
Summary of Amounts Recognized in Statements of Financial Position | (a) The amounts recognized in the statements of financial position are as follows:
|  | December 31, 2021 |  | December 31, 2022
|  | NT$000 |  | NT$000
Present value of defined benefit obligations |  | (959,677) |  | (759,548)
Fair value of plan assets |  | 456,389 |  | 500,333
Net defined benefit liability |  | (503,288) |  | (259,215)
Summary of Movements in net Defined Benefit Liability | (b) Movements in net defined benefit liability are as follows:
|  | 2020
|  | Present value of defined benefit obligations |  | Fair value of plan assets |  | Net defined benefit liability
|  | NT$000 |  | NT$000 |  | NT$000
January 1 |  | (901,159) |  | 421,052 |  | (480,107)
Current services cost |  | (263) |  | — |  | (263)
Interest (expense) income |  | (8,835) |  | 4,171 |  | (4,664)
|  | (910,257) |  | 425,223 |  | (485,034)
Remeasurements: |  |  |  |  |  |
Return on plan assets (excluding amounts included in interest income or expense) |  | — |  | 12,568 |  | 12,568
Financial assumption movement effect |  | (57,180) |  | — |  | (57,180)
Experience adjustments |  | (7,378) |  | — |  | (7,378)
|  | (64,558) |  | 12,568 |  | (51,990)
Pension fund contribution |  | — |  | 25,373 |  | 25,373
Paid pension |  | 31,424 |  | (31,424) |  | —
December 31 |  | (943,391) |  | 431,740 |  | (511,651)
|  | 2021
|  | Present value of defined benefit obligations |  | Fair value of plan assets |  | Net defined benefit liability
|  | NT$000 |  | NT$000 |  | NT$000
January 1 |  | (943,391) |  | 431,740 |  | (511,651)
Current services cost |  | (237) |  | — |  | (237)
Interest (expense) income |  | (4,629) |  | 2,137 |  | (2,492)
|  | (948,257) |  | 433,877 |  | (514,380)
Remeasurements: |  |  |  |  |  |
Return on plan assets (excluding amounts included in interest income or expense) |  | — |  | 5,613 |  | 5,613
Impact on changes in demographic assumptions |  | (20,022) |  | — |  | (20,022)
Financial assumption movement effect |  | 23,757 |  | — |  | 23,757
Experience adjustments |  | (24,347) |  | — |  | (24,347)
|  | (20,612) |  | 5,613 |  | (14,999)
Pension fund contribution |  | — |  | 26,091 |  | 26,091
Paid pension |  | 9,192 |  | (9,192) |  | —
December 31 |  | (959,677) |  | 456,389 |  | (503,288)
|  | 2022
|  | Present value of defined benefit obligations |  | Fair value of plan assets |  | Net defined benefit liability
|  | NT$000 |  | NT$000 |  | NT$000
January 1 |  | (959,677) |  | 456,389 |  | (503,288)
Current services cost |  | (257) |  | — |  | (257)
Interest (expense) income |  | (6,589) |  | 3,161 |  | (3,428)
|  | (966,523) |  | 459,550 |  | (506,973)
Remeasurements: |  |  |  |  |  |
Return on plan assets (excluding amounts included in interest income or expense) |  | — |  | 34,550 |  | 34,550
Financial assumption movement effect |  | 73,218 |  | — |  | 73,218
Experience adjustments |  | 114,466 |  | — |  | 114,466
|  | 187,684 |  | 34,550 |  | 222,234
Pension fund contribution |  | — |  | 25,524 |  | 25,524
Paid pension |  | 19,291 |  | (19,291) |  | —
December 31 |  | (759,548) |  | 500,333 |  | (259,215)
Principal Actuarial Assumptions | (d) The principal actuarial assumptions used were as follows:
|  | Year ended December 31,
|  | 2021 |  | 2022
Discount rate |  | 0.70% |  | 1.50%
Future salary increase |  | 3.50% |  | 3.50%
Sensitivity Analysis of Present Value of Defined Benefit Obligations Effected by Changes of Significant Actuarial Assumptions | The present value of defined benefit obligations is affected by the change in actuarial assumption. The analysis was as follows:
|  | Discount rate |  | Future salary increase
|  | Increase 0.25% |  | Decrease 0.25% |  | Increase 0.25% |  | Decrease 0.25%
|  | NT$000 |  | NT$000 |  | NT$000 |  | NT$000
December 31, 2021 |  |  |  |  |  |  |  |
Effect on present value of defined benefit obligations |  | (28,574) |  | 29,825 |  | 28,941 |  | (27,893)
December 31, 2022 |  |  |  |  |  |  |  |
Effect on present value of defined benefit obligations |  | (20,992) |  | 21,860 |  | 21,385 |  | (20,651)
Analysis of Timing of the Future Pension Payment | (f) As of December 31, 2022, the weighted average duration of that retirement plan is 11.4 years. The analysis of timing of the future pension payment was as follows:
|  | December 31, 2022
|  | NT$000
Within 1 year |  | 32,483
1-2 years |  | 52,470
2-5 years |  | 90,001
5-10 years |  | 168,888
|  | 343,842

X
- Definition The disclosure of additional information about defined benefit plans necessary to meet the objectives of IAS 19. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 137 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_137&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_DisclosureOfAdditionalInformationAboutDefinedBenefitPlansExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of information about the maturity profile of a defined benefit obligation. This will include the weighted average duration of the defined benefit obligation and may include other information about the distribution of the timing of benefit payments, such as a maturity analysis of the benefit payments. [Refer: Defined benefit obligation, at present value] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 147 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_147_c&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_DisclosureOfInformationAboutMaturityProfileOfDefinedBenefitObligationExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of a net defined benefit liability (asset). [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 140 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_140_a&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition The disclosure of a sensitivity analysis for significant actuarial assumptions used to determine the present value of a defined benefit obligation. [Refer: Actuarial assumptions [member]; Defined benefit obligation, at present value] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2022-03-24 -Paragraph 145 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2022-en-r&anchor=para_145&doctype=Standard -URIDate 2022-03-24 + Details
Name: | ifrs-full_DisclosureOfSensitivityAnalysisForActuarialAssumptionsExplanatory
Namespace Prefix: | ifrs-full_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Disclosure of net defined benefit. + References No definition available. + Details
Name: | imos_DisclosureOfNetDefinedBenefitExplanatory
Namespace Prefix: | imos_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Text block [abstract] + References No definition available. + Details
Name: | imos_TextBlockAbstract
Namespace Prefix: | imos_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration