Retirement Plans - Schedule of Deferred Compensation Earnings Credits Included in Noninterest Expense (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Retirement Benefits [Abstract]
Deferred compensation earnings credits included in noninterest expense	$ 121	$ 109	$ 245	$ 254

Deferred compensation arrangements non interest expense.

No definition available.

Name:	tcbk_DeferredCompensationArrangementsNonInterestExpense
Namespace Prefix:	tcbk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration