TriCo Bancshares Condensed Financial Statements (Parent Only) (Details Textual) (USD $)	Mar. 31, 2013	Dec. 31, 2012	Aug. 21, 2007
TriCo Bancshares Condensed Financial Statements (Parent Only) (Textual) [Abstract]
Common stock, no par value
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	16,005,191	16,000,838
Common stock, shares outstanding	16,005,191	16,000,838	15,814,662
Parent [Member]
TriCo Bancshares Condensed Financial Statements (Parent Only) (Textual) [Abstract]
Common stock, no par value
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	16,005,191	16,000,838
Common stock, shares outstanding	16,005,191	16,000,838