v3.25.1
Cover Page
 12 Months Ended
Dec. 31, 2024
shares
Document Information [Line Items]  
Document Type 20-F
Amendment Flag false
Document Period End Date Dec. 31, 2024
Document Fiscal Year Focus 2024
Current Fiscal Year End Date --12-31
Document Fiscal Period Focus FY
Entity Registrant Name Silicon Motion Technology Corporation
Entity Filer Category Large Accelerated Filer
Entity File Number 000-51380
Entity Well-known Seasoned Issuer Yes
Document Annual Report true
Document Transition Report false
Document Shell Company Report false
Document Registration Statement false
Document Accounting Standard U.S. GAAP
Entity Shell Company false
Entity Voluntary Filers No
Entity Emerging Growth Company false
Entity Current Reporting Status Yes
Entity Interactive Data Current Yes
Entity Address, Address Line One Flat C, 19/F, Wing Cheong Commercial Building
Entity Address, Address Line Two Nos 19-25 Jervois Street
Entity Address, Country HK
Entity Central Index Key 0001329394
Entity Address, City or Town Hong Kong Island
Entity Incorporation, State or Country Code E9
Entity Common Stock, Shares Outstanding 134,764,480
Entity Address, Postal Zip Code 0000
ICFR Auditor Attestation Flag true
Auditor Name Deloitte & Touche
Auditor Firm ID 1060
Auditor Location Taipei, Taiwan
Document Financial Statement Error Correction [Flag] false
American Depositary Shares  
Document Information [Line Items]  
Security Exchange Name NASDAQ
Title of 12(b) Security American Depositary Shares, each representing four ordinary shares
Trading Symbol SIMO
Ordinary shares  
Document Information [Line Items]  
Title of 12(b) Security Ordinary shares, US$0.01 par value per share
No Trading Symbol Flag true
Business Contact  
Document Information [Line Items]  
Entity Address, Address Line One 690 N. McCarthy Blvd., Suite 200
Entity Address, Country US
Entity Address, City or Town Milpitas
Entity Address, State or Province CA
Contact Personnel Fax Number 1 408 519 7101
Country Region 1
City Area Code 408
Local Phone Number 519 7200
Entity Address, Postal Zip Code 95035
Contact Personnel Name Jason Tsai