v3.25.4
Document and Entity Information - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Feb. 19, 2026
Jun. 30, 2025
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 000-23877    
Entity Registrant Name Heritage Commerce Corp    
Entity Incorporation, State or Country Code CA    
Entity Tax Identification Number 77-0469558    
Entity Address, Address Line One 224 Airport Parkway    
Entity Address, City or Town San Jose    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 95110    
City Area Code (408)    
Local Phone Number 947-6900    
Title of 12(b) Security Common Stock, No Par Value    
Trading Symbol HTBK    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction false    
Entity Shell Company false    
Entity Public Float     $ 476.8
Entity Common Stock, Shares Outstanding   61,593,284  
Entity Central Index Key 0001053352    
Document Fiscal Period Focus FY    
Amendment Flag false    
Document Fiscal Year Focus 2025    
Documents Incorporated by Reference
None.