Stock Options and Other Equity-Based Incentive Instruments - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Dec. 31, 2024	Apr. 16, 2024	Apr. 16, 2019
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of options (in shares)	0	0
Weighted-average remaining contractual term (in years)	1 year 8 months 26 days
Restricted Stock Units (RSUs) \| Service Condition Vesting RSUs
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of units outstanding expected to vest (in shares)	153,779	152,572
Pre-tax compensation costs	$ 3.9
Number of units released (in shares)	75,845
Restricted Stock Units (RSUs) \| Market Plus Service Condition Vesting RSUs
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of units outstanding expected to vest (in shares)	177,868	144,715
Weighted-average remaining contractual term (in years)	1 year 10 months 24 days
Pre-tax compensation costs	$ 2.0
Number of units released (in shares)	7,911
Restricted Stock Units (RSUs) \| Market Plus Service Condition Vesting RSUs \| Minimum
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of units released (in shares)	0
Restricted Stock Units (RSUs) \| Market Plus Service Condition Vesting RSUs \| Maximum
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Number of units released (in shares)	266,802
2024 Plan
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Aggregate number of shares of TriCo's common stock issued (in shares)			1,200,000
2019 Plan
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Aggregate number of shares of TriCo's common stock issued (in shares)				1,500,000

TRICO BANCSHARES / 10-Q