Junior Subordinated Debt - Summary of Terms and Recorded Balance of Subordinated Debenture (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Oct. 03, 2014
Subordinated Borrowing [Line Items]
Subordinated debenture, Face Value	$ 62,889,000
Subordinated debenture, Recorded Book Value	56,320,000	56,272,000
TriCo Capital Trust I [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Maturity Date	Oct. 07, 2033
Subordinated debenture, Face Value	20,619,000
Subordinated debenture, Current Coupon Rate	3.30%
Subordinated debenture, Recorded Book Value	20,619,000
TriCo Capital Trust II [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Maturity Date	Jul. 23, 2034
Subordinated debenture, Face Value	20,619,000
Subordinated debenture, Current Coupon Rate	2.81%
Subordinated debenture, Recorded Book Value	20,619,000
North Valley Trust II [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Maturity Date	Apr. 24, 2033
Subordinated debenture, Face Value	6,186,000		6,186,000
Subordinated debenture, Current Coupon Rate	3.50%
Subordinated debenture, Recorded Book Value	5,025,000		5,006,000
North Valley Trust III [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Maturity Date	Apr. 24, 2034
Subordinated debenture, Face Value	5,155,000		5,155,000
Subordinated debenture, Current Coupon Rate	3.06%
Subordinated debenture, Recorded Book Value	3,936,000		3,918,000
North Valley Trust IV [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Maturity Date	Mar. 15, 2036
Subordinated debenture, Face Value	10,310,000		10,310,000
Subordinated debenture, Current Coupon Rate	1.60%
Subordinated debenture, Recorded Book Value	$ 6,121,000		$ 6,063,000
LIBOR PLUS [Member] | TriCo Capital Trust I [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Coupon Rate	3.05%
LIBOR PLUS [Member] | TriCo Capital Trust II [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Coupon Rate	2.55%
LIBOR PLUS [Member] | North Valley Trust II [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Coupon Rate	3.25%
LIBOR PLUS [Member] | North Valley Trust III [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Coupon Rate	2.80%
LIBOR PLUS [Member] | North Valley Trust IV [Member]
Subordinated Borrowing [Line Items]
Subordinated debenture, Coupon Rate	1.33%