XML 24 R1.htm IDEA: XBRL DOCUMENT v3.21.1
Cover Page
 12 Months Ended
Dec. 31, 2020
shares
Document Information [Line Items]  
Document Type 20-F
Amendment Flag false
Document Period End Date Dec. 31, 2020
Document Fiscal Year Focus 2020
Document Fiscal Period Focus FY
Entity Registrant Name ChipMOS TECHNOLOGIES INC.
Entity Central Index Key 0001123134
Current Fiscal Year End Date --12-31
Entity Well-known Seasoned Issuer No
Entity Current Reporting Status Yes
Entity Filer Category Accelerated Filer
Entity Emerging Growth Company false
Entity Shell Company false
Entity Common Stock, Shares Outstanding 727,240,126
Document Annual Report true
Document Transition Report false
Entity Interactive Data Current Yes
Document Shell Company Report false
Entity Incorporation, State or Country Code F5
Document Accounting Standard International Financial Reporting Standards
Entity Voluntary Filers No
Entity Address, Country TW
ICFR Auditor Attestation Flag true
ADR [member]  
Document Information [Line Items]  
Trading Symbol IMOS
Title of 12(b) Security American Depositary Shares
Security Exchange Name NASDAQ
Ordinary shares [member]  
Document Information [Line Items]  
Title of 12(b) Security Common Shares, par value NT$10 per share
No Trading Symbol Flag true
Security Exchange Name NASDAQ