XML 44 R1.htm IDEA: XBRL DOCUMENT v3.21.1
Cover Page Cover Page
 3 Months Ended
Apr. 22, 2021
Mar. 31, 2021
Document Information [Line Items]    
Document Type 8-K  
Document Period End Date Apr. 22, 2021  
Entity Registrant Name HERITAGE FINANCIAL CORP  
Entity File Number 000-29480  
Entity Incorporation, State or Country Code WA  
Entity Tax Identification Number 91-1857900  
Entity Address, Address Line One 201 Fifth Avenue SW,  
Entity Address, City or Town Olympia  
Entity Address, State or Province WA  
Entity Address, Postal Zip Code 98501  
City Area Code (360)  
Local Phone Number 943-1500  
Written Communications false  
Soliciting Material false  
Pre-commencement Tender Offer false  
Pre-commencement Issuer Tender Offer false  
Title of 12(b) Security Common stock, no par value  
Trading Symbol HFWA  
Security Exchange Name NASDAQ  
Entity Emerging Growth Company false  
Entity Central Index Key   0001046025
Amendment Flag false