XML 9 R1.htm IDEA: XBRL DOCUMENT v3.20.2
Cover
 3 Months Ended
Jul. 29, 2020
Jun. 30, 2020
Mar. 31, 2020
Cover [Abstract]      
Document Type   8-K  
Document Period End Date Jul. 27, 2020    
Entity Registrant Name   TriCo Bancshares  
Entity Incorporation, State or Country Code CA    
Entity File Number 0-10661    
Entity Tax Identification Number 94-2792841    
Entity Address, Address Line One 63 Constitution Drive    
Entity Address, City or Town Chico,    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 95973    
City Area Code 530    
Local Phone Number 898-0300    
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 TCBK    
Security Exchange Name NASDAQ    
Entity Emerging Growth Company false    
Amendment Flag     false
Entity Central Index Key 0000356171