TriCo Bancshares (TCBK) 10-Q 11 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	Apr. 24, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	TCBK
Entity Registrant Name	TRICO BANCSHARES /
Entity Central Index Key	356171
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		22,740,503

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Assets:
Cash and due from banks	$84,682	$93,150
Cash at Federal Reserve and other banks	196,546	517,578
Cash and cash equivalents	281,228	610,728
Investment securities:
Available for sale	225,126	83,205
Held to maturity	802,482	676,426
Restricted equity securities	16,956	16,956
Loans held for sale	5,413	3,579
Loans	2,320,883	2,282,524
Allowance for loan losses	-36,055	-36,585
Total loans, net	2,284,828	2,245,939
Foreclosed assets, net	5,892	4,894
Premises and equipment, net	42,846	43,493
Cash value of life insurance	93,012	92,337
Accrued interest receivable	9,794	9,275
Goodwill	63,462	63,462
Other intangible assets, net	6,762	7,051
Mortgage servicing rights	7,057	7,378
Other assets	51,002	51,735
Total assets	3,895,860	3,916,458
Deposits:
Noninterest-bearing demand	1,034,012	1,083,900
Interest-bearing	2,315,476	2,296,523
Total deposits	3,349,488	3,380,423
Accrued interest payable	852	978
Reserve for unfunded commitments	2,015	2,145
Other liabilities	53,256	49,192
Other borrowings	9,096	9,276
Junior subordinated debt	56,320	56,272
Total liabilities	3,471,027	3,498,286
Commitments and contingencies (Note 18)
Shareholders' equity:
Common stock, no par value: 50,000,000 shares authorized; issued and outstanding: 22,740,503 at March 31, 2015 22,714,964 at December 31, 2014	245,316	244,318
Retained earnings	181,600	176,057
Accumulated other comprehensive loss, net of tax	-2,083	-2,203
Total shareholders' equity	424,833	418,172
Total liabilities and shareholders' equity	$3,895,860	$3,916,458

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Aug. 21, 2007
Statement of Financial Position [Abstract]
Common stock, no par value
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	22,740,503	22,714,964
Common stock, shares outstanding	22,740,503	22,714,964	15,814,662

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Income (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Interest and dividend income:
Loans, including fees	$31,165	$23,738
Debt securities:
Taxable	5,799	2,822
Tax exempt	161	136
Dividends	336	154
Interest bearing cash at Federal Reserve and other banks	264	309
Total interest and dividend income	37,725	27,159
Interest expense:
Deposits	899	782
Other borrowings	1	1
Junior subordinated debt	482	304
Total interest expense	1,382	1,087
Net interest income	36,343	26,072
Provision for (benefit from reversal of) loan losses	197	-1,355
Net interest income after provision for loan losses	36,146	27,427
Noninterest income:
Service charges and fees	7,344	5,462
Gain on sale of loans	622	464
Commissions on sale of non-deposit investment products	965	771
Increase in cash value of life insurance	675	397
Change in indemnification asset	-65	-412
Gain on sale of foreclosed assets	311	1,227
Other	328	386
Total noninterest income	10,180	8,295
Noninterest expense:
Salaries and related benefits	18,100	13,303
Other	14,182	10,014
Total noninterest expense	32,282	23,317
Income before income taxes	14,044	12,405
Provision for income taxes	5,708	5,040
Net income	$8,336	$7,365
Earnings per share:
Basic	$0.37	$0.46
Diluted	$0.36	$0.45

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$8,336	$5,650	$8,234	$4,859	$7,365
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on available for sale securities arising during the period	9				-60
Change in minimum pension liability	111				5
Other comprehensive income (loss)	120				-55
Comprehensive income	$8,456				$7,310

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Changes in Shareholders' Equity (USD $)	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
In Thousands, except Share data
Beginning balance at Dec. 31, 2013	$250,946	$89,356	$159,733	$1,857
Beginning balance, shares at Dec. 31, 2013		16,076,662
Net income	7,365		7,365
Other comprehensive income (loss)	-55			-55
Stock option vesting	296	296
Stock options exercised	2,495	2,495
Stock options exercised, shares		144,020
Tax benefit of stock options exercised	184	184
Repurchase of common stock	-2,482	-558	-1,924
Repurchase of common stock, shares		-100,385
Dividends paid ($ 0.11 per share)	-1,772		-1,772
Ending balance at Mar. 31, 2014	256,977	91,773	163,402	1,802
Ending balance, shares at Mar. 31, 2014		16,120,297
Beginning balance at Dec. 31, 2014	418,172	244,318	176,057	-2,203
Beginning balance, shares at Dec. 31, 2014	22,714,964	22,714,964
Net income	8,336		8,336
Other comprehensive income (loss)	120			120
Stock option vesting	220	220
RSU vesting	76	76
PSU vesting	28	28
Stock options exercised	887	887
Stock options exercised, shares	47,000	47,000
Tax benefit of stock options exercised	18	18
Repurchase of common stock	-509	-231	-278
Repurchase of common stock, shares		-21,461
Dividends paid ($ 0.11 per share)	-2,515		-2,515
Ending balance at Mar. 31, 2015	$424,833	$245,316	$181,600	($2,083)
Ending balance, shares at Mar. 31, 2015	22,740,503	22,740,503

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Changes in Shareholders' Equity (Parenthetical) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Dividends paid, per share	$0.11	$0.11
Retained Earnings [Member]
Dividends paid, per share	$0.11	$0.11

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Operating activities:
Net income	$8,336	$7,365
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of premises and equipment, and amortization	1,494	1,463
Amortization of intangible assets	289	52
Provision for (benefit from) loan losses	197	-1,355
Amortization of investment securities premium, net	719	156
Originations of loans for resale	-24,527	-13,564
Proceeds from sale of loans originated for resale	23,130	15,056
Gain on sale of loans	-622	-464
Change in market value of mortgage servicing rights	506	181
Provision for losses on foreclosed assets	67	36
Gain on sale of foreclosed assets	-311	-1,227
Loss on disposal of fixed assets	84	1
Increase in cash value of life insurance	-675	-397
Equity compensation vesting expense	324	296
Stock option excess tax benefits	-18	-184
Change in:
Reserve for unfunded commitments	-130	-185
Interest receivable	-519	-174
Interest payable	-126	-73
Other assets and liabilities, net	4,743	5,303
Net cash from operating activities	12,961	12,286
Investing activities:
Proceeds from maturities of securities available for sale	5,280	7,159
Proceeds from maturities of securities held to maturity	19,474	3,730
Purchases of securities available for sale	-147,335
Purchases of securities held to maturity	-146,100	-107,790
Loan origination and principal collections, net	-40,331	-14,326
Improvement of foreclosed assets	-316	-462
Proceeds from sale of other real estate owned	806	5,413
Proceeds from sale of premises and equipment	1	4
Purchases of premises and equipment	-706	-1,577
Net cash used by investing activities	-309,227	-107,849
Financing activities:
Net (decrease) increase in deposits	-30,935	637
Net change in other borrowings	-180	384
Stock option excess tax benefits	18	184
Repurchase of common stock	-27	-293
Dividends paid	-2,515	-1,772
Exercise of stock options	405	306
Net cash used by financing activities	-33,234	-554
Net change in cash and cash equivalents	-329,500	-96,117
Cash and cash equivalents and beginning of year	610,728	598,368
Cash and cash equivalents at end of year	281,228	502,251
Supplemental disclosure of noncash activities:
Unrealized gain (loss) on securities available for sale	15	-104
Loans transferred to foreclosed assets	1,244	713
Market value of shares tendered in-lieu of cash to pay for exercise of options and/or related taxes	509	2,482
Supplemental disclosure of cash flow activity:
Cash paid for interest expense	1,508	1,160
Cash paid for income taxes	$0	$0

Summary_of_Significant_Account

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 1 – Summary of Significant Accounting Policies
	Description of Business and Basis of Presentation
	TriCo Bancshares (the “Company”) is a California corporation organized to act as a bank holding company for Tri Counties Bank (the “Bank”). The Company and the Bank are headquartered in Chico, California. The Bank is a California-chartered bank that is engaged in the general commercial banking business in 26 California counties. Tri Counties Bank currently operates from 57 traditional branches and 16 in-store branches. The Company has five capital subsidiary business trusts (collectively, the Capital Trusts) that issued trust preferred securities, including two organized by TriCo and three acquired with the acquisition of North Valley Bancorp. See Note 17 – Junior Subordinated Debt.
	The consolidated financial statements are prepared in accordance with accounting policies generally accepted in the United States of America and general practices in the banking industry. The financial statements include the accounts of the Company. All inter-company accounts and transactions have been eliminated in consolidation. For financial reporting purposes, the Company’s investments in the Capital Trusts of $1,691,000 are accounted for under the equity method and, accordingly, are not consolidated and are included in other assets on the consolidated balance sheet. The subordinated debentures issued and guaranteed by the Company and held by the Capital Trusts are reflected as debt on the Company’s consolidated balance sheet.
	Use of Estimates in the Preparation of Financial Statements
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company evaluates its estimates on an on-going basis. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.
	As described in Note 2, the Company acquired North Valley Bancorp on October 3, 2014. The acquired assets and assumed liabilities were measured at estimated fair value values under the acquisition method of accounting. The Company made significant estimates and exercised significant judgment in accounting for the acquisition. The Company determined loan fair values based on loan file reviews, loan risk ratings, appraised collateral values, expected cash flows and historical loss factors. Foreclosed assets were primarily valued based on appraised values of the repossessed loan collateral. Land and building were valued based on appraised values. An identifiable intangible was also recorded representing the fair value of the core deposit customer base based on an evaluation of the cost of such deposits relative to alternative funding sources. The fair value of time deposits and borrowings were determined based on the present value of estimated future cash flows using current rates as of the acquisition date.
	Significant Group Concentration of Credit Risk
	The Company grants agribusiness, commercial, consumer, and residential loans to customers located throughout the northern San Joaquin Valley, the Sacramento Valley and northern mountain regions of California. The Company has a diversified loan portfolio within the business segments located in this geographical area. The Company currently classifies all its operation into one business segment that it denotes as community banking.
	Cash and Cash Equivalents
	For purposes of the consolidated statements of cash flows, cash and cash equivalents include cash on hand, amounts due from banks, and federal funds sold. Net cash flows are reported for loan and deposit transactions and other borrowings.
	Investment Securities
	The Company classifies its debt and marketable equity securities into one of three categories: trading, available for sale or held to maturity. Trading securities are bought and held principally for the purpose of selling in the near term. Held to maturity securities are those securities which the Company has the ability and intent to hold until maturity. These securities are carried at cost adjusted for amortization of premium and accretion of discount, computed by the effective interest method over their contractual lives. All other securities not included in trading or held to maturity are classified as available for sale. Available for sale securities are recorded at fair value. Unrealized gains and losses, net of the related tax effect, on available for sale securities are reported as a separate component of other accumulated comprehensive income in shareholders’ equity until realized. Premiums and discounts are amortized or accreted over the life of the related investment security as an adjustment to yield using the effective interest method. Dividend and interest income are recognized when earned. Realized gains and losses are derived from the amortized cost of the security sold. During the three months ended March 31, 2015, and the year ended December 31, 2014, the Company did not have any securities classified as trading.
	The Company assesses other-than-temporary impairment (“OTTI”) based on whether it intends to sell a security or if it is likely that the Company would be required to sell the security before recovery of the amortized cost basis of the investment, which may be maturity. For debt securities, if we intend to sell the security or it is likely that we will be required to sell the security before recovering its cost basis, the entire impairment loss would be recognized in earnings as an OTTI. If we do not intend to sell the security and it is not likely that we will be required to sell the security but we do not expect to recover the entire amortized cost basis of the security, only the portion of the impairment loss representing credit losses would be recognized in earnings. The credit loss on a security is measured as the difference between the amortized cost basis and the present value of the cash flows expected to be collected. Projected cash flows are discounted by the original or current effective interest rate depending on the nature of the security being measured for potential OTTI. The remaining impairment related to all other factors, the difference between the present value of the cash flows expected to be collected and fair value, is recognized as a charge to other comprehensive income (“OCI”). Impairment losses related to all other factors are presented as separate categories within OCI. The accretion of the amount recorded in OCI increases the carrying value of the investment and does not affect earnings. If there is an indication of additional credit losses the security is re-evaluated according to the procedures described above. No OTTI losses were recognized during the three months ended March 31, 2015 or the year ended December 31, 2014.
	Restricted Equity Securities
	Restricted equity securities represent the Company’s investment in the stock of the Federal Home Loan Bank of San Francisco (“FHLB”) and are carried at par value, which reasonably approximates its fair value. While technically these are considered equity securities, there is no market for the FHLB stock. Therefore, the shares are considered as restricted investment securities. Management periodically evaluates FHLB stock for other-than-temporary impairment. Management’s determination of whether these investments are impaired is based on its assessment of the ultimate recoverability of cost rather than by recognizing temporary declines in value. The determination of whether a decline affects the ultimate recoverability of cost is influenced by criteria such as (1) the significance of any decline in net assets of the FHLB as compared to the capital stock amount for the FHLB and the length of time this situation has persisted, (2) commitments by the FHLB to make payments required by law or regulation and the level of such payments in relation to the operating performance of the FHLB, (3) the impact of legislative and regulatory changes on institutions and, accordingly, the customer base of the FHLB, and (4) the liquidity position of the FHLB.
	As a member of the FHLB system, the Company is required to maintain a minimum level of investment in FHLB stock based on specific percentages of its outstanding mortgages, total assets, or FHLB advances. The Company may request redemption at par value of any stock in excess of the minimum required investment. Stock redemptions are at the discretion of the FHLB.
	Loans Held for Sale
	Loans originated and intended for sale in the secondary market are carried at the lower of aggregate cost or fair value, as determined by aggregate outstanding commitments from investors of current investor yield requirements. Net unrealized losses are recognized through a valuation allowance by charges to noninterest income.
	Mortgage loans held for sale are generally sold with the mortgage servicing rights retained by the Company. Gains or losses on the sale of loans that are held for sale are recognized at the time of the sale and determined by the difference between net sale proceeds and the net book value of the loans less the estimated fair value of any retained mortgage servicing rights.
	Loans and Allowance for Loan Losses
	Loans originated by the Company, i.e., not purchased or acquired in a business combination, are referred to as originated loans. Originated loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the principal amount outstanding, net of deferred loan fees and costs. Loan origination and commitment fees and certain direct loan origination costs are deferred, and the net amount is amortized as an adjustment of the related loan’s yield over the actual life of the loan. Originated loans on which the accrual of interest has been discontinued are designated as nonaccrual loans.
	Originated loans are placed in nonaccrual status when reasonable doubt exists as to the full, timely collection of interest or principal, or a loan becomes contractually past due by 90 days or more with respect to interest or principal and is not well secured and in the process of collection. When an originated loan is placed on nonaccrual status, all interest previously accrued but not collected is reversed. Income on such loans is then recognized only to the extent that cash is received and where the future collection of principal is probable. Interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of Management, the loan is estimated to be fully collectible as to both principal and interest.
	An allowance for loan losses for originated loans is established through a provision for loan losses charged to expense. The allowance is maintained at a level which, in Management’s judgment, is adequate to absorb probable incurred credit losses inherent in the loan portfolio as of the balance sheet date. Originated loans and deposit related overdrafts are charged against the allowance for loan losses when Management believes that the collectability of the principal is unlikely or, with respect to consumer installment loans, according to an established delinquency schedule. The allowance is an amount that Management believes will be adequate to absorb probable incurred losses inherent in existing loans, based on evaluations of the collectability, impairment and prior loss experience of loans. The evaluations take into consideration such factors as changes in the nature and size of the portfolio, overall portfolio quality, loan concentrations, specific problem loans, and current economic conditions that may affect the borrower’s ability to pay. The Company defines an originated loan as impaired when it is probable the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. Impaired originated loans are measured based on the present value of expected future cash flows discounted at the loan’s original effective interest rate. As a practical expedient, impairment may be measured based on the loan’s observable market price or the fair value of the collateral if the loan is collateral dependent. When the measure of the impaired loan is less than the recorded investment in the loan, the impairment is recorded through a valuation allowance.
	In situations related to originated loans where, for economic or legal reasons related to a borrower’s financial difficulties, the Company grants a concession for other than an insignificant period of time to the borrower that the Company would not otherwise consider, the related loan is classified as a troubled debt restructuring (TDR). The Company strives to identify borrowers in financial difficulty early and work with them to modify to more affordable terms before their loan reaches nonaccrual status. These modified terms may include rate reductions, principal forgiveness, payment forbearance and other actions intended to minimize the economic loss and to avoid foreclosure or repossession of the collateral. In cases where the Company grants the borrower new terms that result in the loan being classified as a TDR, the Company measures any impairment on the restructuring as noted above for impaired loans. TDR loans are classified as impaired until they are fully paid off or charged off. Loans that are in nonaccrual status at the time they become TDR loans, remain in nonaccrual status until the borrower demonstrates a sustained period of performance which the Company generally believes to be six consecutive months of payments, or equivalent. Otherwise, TDR loans are subject to the same nonaccrual and charge-off policies as noted above with respect to their restructured principal balance.
	Credit risk is inherent in the business of lending. As a result, the Company maintains an allowance for loan losses to absorb probable incurred losses inherent in the Company’s originated loan portfolio. This is maintained through periodic charges to earnings. These charges are included in the Consolidated Statements of Income as provision for loan losses. All specifically identifiable and quantifiable losses are immediately charged off against the allowance. However, for a variety of reasons, not all losses are immediately known to the Company and, of those that are known, the full extent of the loss may not be quantifiable at that point in time. The balance of the Company’s allowance for originated loan losses is meant to be an estimate of these unknown but probable losses inherent in the portfolio.
	The Company formally assesses the adequacy of the allowance for originated loan losses on a quarterly basis. Determination of the adequacy is based on ongoing assessments of the probable risk in the outstanding originated loan portfolio, and to a lesser extent the Company’s originated loan commitments. These assessments include the periodic re-grading of credits based on changes in their individual credit characteristics including delinquency, seasoning, recent financial performance of the borrower, economic factors, changes in the interest rate environment, growth of the portfolio as a whole or by segment, and other factors as warranted. Loans are initially graded when originated. They are re-graded as they are renewed, when there is a new loan to the same borrower, when identified facts demonstrate heightened risk of nonpayment, or if they become delinquent. Re-grading of larger problem loans occurs at least quarterly. Confirmation of the quality of the grading process is obtained by independent credit reviews conducted by consultants specifically hired for this purpose and by various bank regulatory agencies.
	The Company’s method for assessing the appropriateness of the allowance for originated loan losses includes specific allowances for impaired originated loans, formula allowance factors for pools of credits, and allowances for changing environmental factors (e.g., interest rates, growth, economic conditions, etc.). Allowance factors for loan pools were based on historical loss experience by product type and prior risk rating.
	During the three months ended March 31, 2014, the Company modified its methodology used to determine the allowance for changing environmental factors by adding a new environmental factor based on the California Home Affordability Index (“CHAI”). The CHAI measures the percentage of households in California that can afford to purchase the median priced home in California based on current home prices and mortgage interest rates. The use of the CHAI environmental factor consists of comparing the current CHAI to its historical baseline, and allows management to consider the adverse impact that a lower than historical CHAI may have on general economic activity and the performance of our borrowers. Based on an analysis of historical data, management believes this environmental factor gives a better estimate of current economic activity compared to other environmental factors that may lag current economic activity to some extent. This change in methodology resulted in no change to the allowance for loan losses as of March 31, 2014 compared to what it would have been without this change in methodology.
	During the three months ended June 30, 2014, the Company refined the method it uses to evaluate historical losses for the purpose of estimating the pool allowance for unimpaired loans. In the third quarter of 2010, the Company moved from a six point grading system (Grades A-F) to a nine point risk rating system (Risk Ratings 1-9), primarily to allow for more distinction within the “Pass” risk rating. Initially, there was not sufficient loss experience within the nine point scale to complete a migration analysis for all nine risk ratings, all loans risk rated Pass or 2-5 were grouped together, a loss rate was calculated for that group, and that loss rate was established as the loss rate for risk rating 4. The reserve ratios for risk ratings 2, 3 and 5 were then interpolated from that figure. As of June 30, 2014, the Company was able to compile twelve quarters of historical loss information for all risk ratings and use that information to calculate the loss rates for each of the nine risk ratings without interpolation. This refinement led to an increase of $1,438,000 in the reserve requirement for unimpaired loans, driven primarily by home equity lines of credit with a risk rating of 5 or “Pass-Watch.”
	Loans purchased or acquired in a business combination are referred to as acquired loans. Acquired loans are valued as of the acquisition date in accordance with Financial Accounting Standards Board Accounting Standards Codification (“FASB ASC”) Topic 805, Business Combinations. Loans acquired with evidence of credit deterioration since origination for which it is probable that all contractually required payments will not be collected are referred to as purchased credit impaired (PCI) loans. PCI loans are accounted for under FASB ASC Topic 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality. Under FASB ASC Topic 805 and FASB ASC Topic 310-30, PCI loans are recorded at fair value at acquisition date, factoring in credit losses expected to be incurred over the life of the loan. Accordingly, an allowance for loan losses is not carried over or recorded as of the acquisition date. Fair value is defined as the present value of the future estimated principal and interest payments of the loan, with the discount rate used in the present value calculation representing the estimated effective yield of the loan. Default rates, loss severity, and prepayment speed assumptions are periodically reassessed and our estimate of future payments is adjusted accordingly. The difference between contractual future payments and estimated future payments is referred to as the nonaccretable difference. The difference between estimated future payments and the present value of the estimated future payments is referred to as the accretable yield. The accretable yield represents the amount that is expected to be recorded as interest income over the remaining life of the loan. If after acquisition, the Company determines that the estimated future cash flows of a PCI loan are expected to be more than originally estimated, an increase in the discount rate (effective yield) would be made such that the newly increased accretable yield would be recognized, on a level yield basis, over the remaining estimated life of the loan. If, after acquisition, the Company determines that the estimated future cash flows of a PCI loan are expected to be less than previously estimated, the discount rate would first be reduced until the present value of the reduced cash flow estimate equals the previous present value however, the discount rate may not be lowered below its original level at acquisition. If the discount rate has been lowered to its original level and the present value has not been sufficiently lowered, an allowance for loan loss would be established through a provision for loan losses charged to expense to decrease the present value to the required level. If the estimated cash flows improve after an allowance has been established for a loan, the allowance may be partially or fully reversed depending on the improvement in the estimated cash flows. Only after the allowance has been fully reversed may the discount rate be increased. PCI loans are put on nonaccrual status when cash flows cannot be reasonably estimated. PCI loans on nonaccrual status are accounted for using the cost recovery method or cash basis method of income recognition. The Company refers to PCI loans on nonaccrual status that are accounted for using the cash basis method of income recognition as “PCI – cash basis” loans; and the Company refers to all other PCI loans as “PCI – other” loans PCI loans are charged off when evidence suggests cash flows are not recoverable. Foreclosed assets from PCI loans are recorded in foreclosed assets at fair value with the fair value at time of foreclosure representing cash flow from the loan. ASC 310-30 allows PCI loans with similar risk characteristics and acquisition time frame to be “pooled” and have their cash flows aggregated as if they were one loan. The Company elected to use the “pooled” method of ASC 310-30 for PCI – other loans in the acquisition of certain assets and liabilities of Granite Community Bank, N.A. (“Granite”) during 2010 and Citizens Bank of Northern California (“Citizens”) during 2011.
	Acquired loans that are not PCI loans are referred to as purchased not credit impaired (PNCI) loans. PNCI loans are accounted for under FASB ASC Topic 310-20, Receivables – Nonrefundable Fees and Other Costs, in which interest income is accrued on a level-yield basis for performing loans. For income recognition purposes, this method assumes that all contractual cash flows will be collected, and no allowance for loan losses is established at the time of acquisition. Post-acquisition date, an allowance for loan losses may need to be established for acquired loans through a provision charged to earnings for credit losses incurred subsequent to acquisition. Under ASC 310-20, the loss would be measured based on the probable shortfall in relation to the contractual note requirements, consistent with our allowance for loan loss policy for similar loans.
	Throughout these financial statements, and in particular in Note 4 and Note 5, when we refer to “Loans” or “Allowance for loan losses” we mean all categories of loans, including Originated, PNCI, PCI – cash basis, and PCI - other. When we are not referring to all categories of loans, we will indicate which we are referring to – Originated, PNCI, PCI – cash basis, or PCI - other.
	When referring to PNCI and PCI loans we use the terms “nonaccretable difference”, “accretable yield”, or “purchase discount”. Nonaccretable difference is the difference between undiscounted contractual cash flows due and undiscounted cash flows we expect to collect, or put another way, it is the undiscounted contractual cash flows we do not expect to collect. Accretable yield is the difference between undiscounted cash flows we expect to collect and the value at which we have recorded the loan on our financial statements. On the date of acquisition, all purchased loans are recorded on our consolidated financial statements at estimated fair value. Purchase discount is the difference between the estimated fair value of loans on the date of acquisition and the principal amount owed by the borrower, net of charge offs, on the date of acquisition. We may also refer to “discounts to principal balance of loans owed, net of charge-offs”. Discounts to principal balance of loans owed, net of charge-offs is the difference between principal balance of loans owed, net of charge-offs, and loans as recorded on our financial statements. Discounts to principal balance of loans owed, net of charge-offs arise from purchase discounts, and equal the purchase discount on the acquisition date.
	Loans are also categorized as “covered” or “noncovered”. Covered loans refer to loans covered by a Federal Deposit Insurance Corporation (“FDIC”) loss sharing agreement. Noncovered loans refer to loans not covered by a FDIC loss sharing agreement.
	Foreclosed Assets
	Foreclosed assets include assets acquired through, or in lieu of, loan foreclosure. Foreclosed assets are held for sale and are initially recorded at fair value less estimated costs to sell at the date of foreclosure, establishing a new cost basis. Subsequent to foreclosure, management periodically performs valuations and the assets are carried at the lower of carrying amount or fair value less cost to sell. Revenue and expenses from operations and changes in the valuation allowance are included in other noninterest expense. Gain or loss on sale of foreclosed assets is included in noninterest income. Foreclosed assets that are not subject to a FDIC loss-share agreement are referred to as noncovered foreclosed assets.
	Foreclosed assets acquired through FDIC-assisted acquisitions that are subject to a FDIC loss-share agreement, and all assets acquired via foreclosure of covered loans are referred to as covered foreclosed assets. Covered foreclosed assets are reported exclusive of expected reimbursement cash flows from the FDIC. Foreclosed covered loan collateral is transferred into covered foreclosed assets at the loan’s carrying value, inclusive of the acquisition date fair value discount.
	Covered foreclosed assets are initially recorded at estimated fair value less estimated costs to sell on the acquisition date based on similar market comparable valuations less estimated selling costs. Any subsequent valuation adjustments due to declines in fair value will be charged to noninterest expense, and will be mostly offset by noninterest income representing the corresponding increase to the FDIC indemnification asset for the offsetting loss reimbursement amount. Any recoveries of previous valuation adjustments will be credited to noninterest expense with a corresponding charge to noninterest income for the portion of the recovery that is due to the FDIC.
	Premises and Equipment
	Land is carried at cost. Land improvements, buildings and equipment, including those acquired under capital lease, are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expenses are computed using the straight-line method over the estimated useful lives of the related assets or lease terms. Asset lives range from 3-10 years for furniture and equipment and 15-40 years for land improvements and buildings.
	Goodwill and Other Intangible Assets
	Goodwill represents the excess of costs over fair value of net assets of businesses acquired. Goodwill and other intangible assets acquired in a purchase business combination and determined to have an indefinite useful life are not amortized, but instead tested for impairment at least annually. Intangible assets with estimable useful lives are amortized over their respective estimated useful lives to their estimated residual values, and reviewed for impairment.
	The Company has an identifiable intangible asset consisting of core deposit intangibles (CDI). CDI are amortized over their respective estimated useful lives, and reviewed for impairment.
	Impairment of Long-Lived Assets and Goodwill
	Long-lived assets, such as premises and equipment, and purchased intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated. The assets and liabilities of a disposed group classified as held for sale would be presented separately in the appropriate asset and liability sections of the consolidated balance sheet.
	As of December 31 of each year, goodwill is tested for impairment, and is tested for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount exceeds the asset’s fair value. This determination is made at the reporting unit level. The Company may choose to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then goodwill is deemed not to be impaired. However, if the Company concludes otherwise, or if the Company elected not to first assess qualitative factors, then the Company performs the first step of a two-step impairment test by calculating the fair value of the reporting unit and comparing the fair value with the carrying amount of the reporting unit. Second, if the carrying amount of the reporting unit exceeds its fair value, an impairment loss is recognized for any excess of the carrying amount of the reporting unit’s goodwill over the implied fair value of that goodwill. The implied fair value of goodwill is determined by allocating the fair value of the reporting unit in a manner similar to a purchase price allocation. The residual fair value after this allocation is the implied fair value of the reporting unit goodwill. Currently, and historically, the Company is comprised of only one reporting unit that operates within the business segment it has identified as “community banking”. Goodwill was not impaired as of December 31, 2014 because the fair value of the reporting unit exceeded its carrying value.
	Mortgage Servicing Rights
	Mortgage servicing rights (MSR) represent the Company’s right to a future stream of cash flows based upon the contractual servicing fee associated with servicing mortgage loans. Our MSR arise from residential and commercial mortgage loans that we originate and sell, but retain the right to service the loans. The net gain from the retention of the servicing right is included in gain on sale of loans in noninterest income when the loan is sold. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, the custodial earnings rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses. Servicing fees are recorded in noninterest income when earned.
	The Company accounts for MSR at fair value. The determination of fair value of our MSR requires management judgment because they are not actively traded. The determination of fair value for MSR requires valuation processes which combine the use of discounted cash flow models and extensive analysis of current market data to arrive at an estimate of fair value. The cash flow and prepayment assumptions used in our discounted cash flow model are based on empirical data drawn from the historical performance of our MSR, which we believe are consistent with assumptions used by market participants valuing similar MSR, and from data obtained on the performance of similar MSR. The key assumptions used in the valuation of MSR include mortgage prepayment speeds and the discount rate. These variables can, and generally will, change from quarter to quarter as market conditions and projected interest rates change. The key risks inherent with MSR are prepayment speed and changes in interest rates. The Company uses an independent third party to determine fair value of MSR.
	Indemnification Asset/Liability
	The Company accounts for amounts receivable or payable under its loss-share agreements entered into with the FDIC in connection with its purchase and assumption of certain assets and liabilities of Granite as indemnification assets in accordance with FASB ASC Topic 805, Business Combinations. FDIC indemnification assets are initially recorded at fair value, based on the discounted value of expected future cash flows under the loss-share agreements. The difference between the fair value and the undiscounted cash flows the Company expects to collect from or pay to the FDIC will be accreted into noninterest income over the life of the FDIC indemnification asset. FDIC indemnification assets are reviewed quarterly and adjusted for any changes in expected cash flows based on recent performance and expectations for future performance of the covered portfolios. These adjustments are measured on the same basis as the related covered loans and covered other real estate owned. Any increases in cash flow of the covered assets over those expected will reduce the FDIC indemnification asset and any decreases in cash flow of the covered assets under those expected will increase the FDIC indemnification asset. Increases and decreases to the FDIC indemnification asset are recorded as adjustments to noninterest income.
	Reserve for Unfunded Commitments
	The reserve for unfunded commitments is established through a provision for losses – unfunded commitments charged to noninterest expense. The reserve for unfunded commitments is an amount that Management believes will be adequate to absorb probable losses inherent in existing commitments, including unused portions of revolving lines of credits and other loans, standby letters of credits, and unused deposit account overdraft privilege. The reserve for unfunded commitments is based on evaluations of the collectability, and prior loss experience of unfunded commitments. The evaluations take into consideration such factors as changes in the nature and size of the loan portfolio, overall loan portfolio quality, loan concentrations, specific problem loans and related unfunded commitments, and current economic conditions that may affect the borrower’s or depositor’s ability to pay.
	Income Taxes
	The Company’s accounting for income taxes is based on an asset and liability approach. The Company recognizes the amount of taxes payable or refundable for the current year, and deferred tax assets and liabilities for the future tax consequences that have been recognized in its financial statements or tax returns. The measurement of tax assets and liabilities is based on the provisions of enacted tax laws. A valuation allowance, if needed, reduces deferred tax assets to the expected amount most likely to be realized. Realization of deferred tax assets is dependent upon the generation of a sufficient level of future taxable income and recoverable taxes paid in prior years. Although realization is not assured, management believes it is more likely than not that all of the deferred tax assets will be realized. Interest and/or penalties related to income taxes are reported as a component of noninterest income.
	Off-Balance Sheet Credit Related Financial Instruments
	In the ordinary course of business, the Company has entered into commitments to extend credit, including commitments under credit card arrangements, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded when they are funded.
	Geographical Descriptions
	For the purpose of describing the geographical location of the Company’s loans, the Company has defined northern California as that area of California north of, and including, Stockton; central California as that area of the state south of Stockton, to and including, Bakersfield; and southern California as that area of the state south of Bakersfield.
	Reclassifications
	Certain amounts reported in previous consolidated financial statements have been reclassified to conform to the presentation in this report. These reclassifications did not affect previously reported net income or total shareholders’ equity.
	Recent Accounting Pronouncements
	FASB issued ASU No. 2014-04, Receivables (Topic 310): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-04 clarifies when an in substance repossession or foreclosure occurs, that is, when a creditor should be considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan such that the loan receivable should be derecognized and the real estate property recognized. ASU 2014-04 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
FASB issued ASU No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. ASU 2014-08 improves the definition of discontinued operations by limiting discontinued operations reporting to disposals of components of an entity that represent strategic shifts that have (or will have) a major effect on an entity’s operations and financial results. ASU 2014-08 requires expanded disclosures for discontinued operations that provide users of financial statements with more information about the assets, liabilities, revenues, and expenses of discontinued operations. ASU 2014-08 also requires an entity to disclose the pretax profit or loss of an individually significant component of an entity that does not qualify for discontinued operations reporting, and provide users with information about the financial effects of significant disposals that do not qualify for discontinued operations reporting. The amendments in ASU 2014-08 include several changes to the Accounting Standards Codification to improve the organization and readability of Subtopic 205-20 and Subtopic 360-10, Property, Plant, and Equipment—Overall. ASU 2014-08 is effective for public business entities for annual periods, and interim periods within those annual periods, beginning after December 15, 2014. ASU 2014-08 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of the guidance under ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 is effective for a public entity for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. ASU 2014-09 is not expected to have a significant impact on the Company’s consolidated financial statements.
FASB issued ASU No. 2014-11, Transfers and Servicing (Topic 860): Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. ASU 2014-11 requires that repurchase-to-maturity transactions be accounted for as secured borrowings consistent with the accounting for other repurchase agreements. In addition, ASU 2014-11 requires separate accounting for repurchase financings, which entails the transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty. ASU 2014-11 requires entities to disclose certain information about transfers accounted for as sales in transactions that are economically similar to repurchase agreements. In addition, ASU 2014-11 requires disclosures related to collateral, remaining contractual tenor and of the potential risks associated with repurchase agreements, securities lending transactions and repurchase-to-maturity transactions. ASU 2014-11 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
FASB issued ASU No. 2014-12, Compensation—Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be achieved after the Requisite Service Period. ASU 2014-12 requires that a performance target that affects the vesting of a share-based payment award and that could be achieved after the requisite service period be treated as a performance condition. A reporting entity should apply existing guidance in Topic 718 as it relates to awards with performance conditions that affect vesting to account for such awards. As such, the performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. The stated vesting period (which includes the period in which the performance target could be achieved) may differ from the requisite service period. Current U.S. GAAP does not contain explicit guidance on whether to treat a performance target that could be achieved after the requisite service period as a performance condition that affects vesting or as a nonvesting condition that affects the grant-date fair value of an award. ASU 2014-12 provides explicit guidance for those awards. For all entities, ASU 2014-12 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. Earlier adoption is permitted. The Company has elected to not adopt ASU 2014-12 early.
FASB issued ASU No. 2014-14, Receivables—Troubled Debt Restructurings by Creditors (Topic 310): Classification of Certain Government Mortgage Loans upon Foreclosure. ASU 2014-14 requires that a mortgage loan be derecognized and that a separate other receivable be recognized upon foreclosure if the following conditions are met: 1) the loan has a government guarantee that is not separable from the loan before foreclosure, 2) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim, and 3) at the time of foreclosure, any amount of the claim that is determined on the basis of the fair value of the real estate is fixed. Upon foreclosure, the separate other receivable should be measured based on the amount of the loan balance (principal and interest) expected to be recovered from the guarantor. ASU 2014-14 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.

Business_Combinations

Business Combinations	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Business Combinations	Note 2 – Business Combinations
	On October 3, 2014, TriCo completed its acquisition of North Valley Bancorp originally announced January 21, 2014. Based on a fixed exchange ratio of 0.9433 shares of TriCo common stock for each share of North Valley Bancorp common stock, North Valley Bancorp shareholders received 6,575,550 shares of TriCo common stock and $6,823 of cash in-lieu of fractional shares. The 6,575,550 shares of TriCo common stock issued to North Valley Bancorp shareholders represented, on a pro forma basis, approximately 28.9% of the 22,714,964 shares of the combined company outstanding on October 3, 2014. Based on TriCo’s closing stock price of $23.01 on October 3, 2014, North Valley Bancorp shareholders received consideration valued at $151,310,000 or approximately $21.71 per share of North Valley common stock outstanding.
	The acquisition of North Valley Bancorp was to expand the Company’s market presence in Northern California. The customer base and locations of North Valley Bancorp’s branches had significant overlap when compared to the Company’s Northern California customer base and branch locations. This made North Valley Bancorp a very good fit in terms of potential cost savings and future growth potential. With the levels of excess capital at the time, the acquisitions fit well into the Company’s growth strategy.
	North Valley Bancorp, was headquartered in Redding, California, and was the parent of North Valley Bank that had approximately $935 million in assets and 22 commercial banking offices in Shasta, Humboldt, Del Norte, Mendocino, Yolo, Sonoma, Placer and Trinity Counties in Northern California at June 30, 2014. In connection with the acquisition, North Valley Bank was merged into Tri Counties Bank on October 3, 2014.
	On October 25, 2014, North Valley Bank’s electronic customer service and other data processing systems were converted into Tri Counties Bank’s systems. Between January 7, 2015 and January 21, 2015, four Tri Counties Bank branches and four former North Valley Bank branches were consolidated into other Tri Counties Bank or other former North Valley Bank branches.
	Beginning on October 4, 2014, the effect of revenue and expenses from the operations of North Valley Bancorp, and the issuance of TriCo Bancshares common shares as consideration in the merger are included in the results of the Company.
	The assets acquired and liabilities assumed from North Valley Bancorp were accounted for in accordance with ASC 805 “Business Combinations,” using the acquisition method of accounting and were recorded at their estimated fair values on the October 3, 2014 acquisition date, and its results of operations are included in the Company’s consolidated statements of income since that date. These fair value estimates are considered provisional, as additional analysis will be performed on certain assets and liabilities in which fair values are primarily determined through the use of inputs that are not observable from market-based information. Management may further adjust the provisional fair values for a period of up to one year from the date of the acquisition. The excess of the fair value of consideration transferred over total identifiable net assets was recorded as goodwill. The goodwill arising from the acquisition consists largely of the synergies and economies of scale expected from combining the operations of the Company and North Valley Bancorp. None of the goodwill is deductible for income tax purposes as the acquisition was accounted for as a tax-free exchange. The assets and liabilities that continue to be provisional include loans, intangible assets, OREO, deferred tax assets, accrued assets and liabilities, and the residual effects that the adjustments would have on goodwill.
	The following table discloses the calculation of the fair value of consideration transferred, the total identifiable net assets acquired and the resulting goodwill relating to the North Valley Bancorp acquisition:
	(in thousands)	North Valley Bancorp
		October 3, 2014
	Fair value of consideration transferred:
	Fair value of shares issued	$	151,303
	Cash consideration		7
	Total fair value of consideration transferred		151,310
	Asset acquired:
	Cash and cash equivalents		141,412
	Securities available for sale		17,288
	Securities held to maturity		189,950
	Restricted equity securities		5,378
	Loans		499,327
	Foreclosed assets		695
	Premises and equipment		11,936
	Cash value of life insurance		38,075
	Core deposit intangible		6,614
	Other assets		20,064
	Total assets acquired		930,739
	Liabilities assumed:
	Deposits		801,956
	Other liabilities		10,429
	Junior subordinated debt		14,987
	Total liabilities assumed		827,372
	Total net assets acquired		103,367
	Goodwill recognized	$	47,943
	A summary of the estimated fair value adjustments resulting in the goodwill recorded in the North Valley Bancorp acquisition are presented below:
	(in thousands)	North Valley Bancorp
		October 3, 2014
	Value of stock consideration paid to North Valley Bancorp Shareholders	$	151,303
	Cash payments to North Valley Bancorp Shareholders		7
	Cost basis net assets acquired		(98,040	)
	Fair value adjustments:
	Loans		5,832
	Premises and Equipment		(4,785	)
	Core deposit intangible		(6,283	)
	Deferred income taxes		6,293
	Junior subordinated debt		(6,664	)
	Other		280
	Goodwill	$	47,943
	The loan portfolio of North Valley Bancorp was recorded at fair value at the date of each acquisition. A valuation of North Valley Bancorp’s loan portfolio was performed as of the acquisition date to assess the fair value of the loan portfolio. The North Valley Bancorp loan portfolio was segmented into two groups; loans with credit deterioration (PCI loans) and loans without credit deterioration (PNCI). For North Valley Bancorp PNCI loans, the present value of estimated future cash flows, based primarily on contractual cash flows, was used to determine fair value. For North Valley Bancorp PCI loans, the present value of estimated future cash flows, based primarily on liquidation value of collateral, was used to determine fair value.
	North Valley Bancorp PNCI loans were grouped into pools based on similar loan characteristics such as loan type, payment amortization method, and fixed or variable interest rates. A discounted cash flow schedule was prepared for each pool in which the present value of all estimated future cash flows was calculated using a specifically calculated discount rate for each pool. The discount rate used to estimate the fair value of each loan pool was composed of the sum of: an estimated cost of funds rate, an estimated capital charge reflecting the market participant required return on capital, estimated loan servicing costs, and a liquidity premium. All PNCI loan pools included some estimate regarding prepayment rates, and estimated principal default and loss rates, based primarily on North Valley Bancorp’s historical loss experience. The difference between the sum of recorded balances of the North Valley Bancorp PNCI loans in each pool and the present value of each pool represented the total discount (if the recorded value exceeded the present value) or premium (if the present value exceeded the recorded value) for each pool. The total discount, or premium, for each pool was then allocated to the individual loans within each pool based on outstanding loan balance, individual loan risk rating as compared to the weighted average risk rating of the pool, and the contractual payments remaining for the individual loan as compared to the pool.
	North Valley Bancorp PCI loans were fair valued on an individual basis. A discounted cash flow schedule was prepared for each loan in which the present value of all future estimated cash flows was calculated using a specifically calculated discount rate, estimated liquidation value and estimated liquidation timing for each loan. The discount rate used in the calculation of the present value of North Valley Bancorp PCI loans was composed of the sum of: an estimated cost of funds rate, an estimated capital charge reflecting the market participant required return on capital, estimated loan servicing costs, and a liquidity premium. The difference between the recorded balance and the present value of each North Valley Bancorp PCI loan represented the discount for each PCI loan. All North Valley Bancorp PCI loans had recorded values in excess of their present value of estimated future cash flows.
	The Company identified the North Valley Bancorp PCI loans as having cash flows that were not reasonably estimable and placed these loans in nonaccrual status under ASC 310-30 and included them in the category of loans the Company refers to as “PCI – other” loans.
	The following table presents the cost basis, fair value discount, and fair value of loans acquired from North Valley Bancorp on October 3, 2014:
		North Valley Bancorp Acquired Loans
		3-Oct-14
	(in thousands)	Cost Basis			Discount			Fair Value
	PNCI	$	502,637		$	(12,721	)	$	489,916
	PCI – other		11,488			(2,077	)		9,411
	Total	$	514,125		$	(14,798	)	$	499,327
	Although the discount on PNCI loans is completely accretable to interest income over the remaining life of such loans, the discount on PCI – other loans from the North Valley Bancorp acquisition are not accretable into interest income until the loan principal balance has been reduced to the loan’s fair value recorded at acquisition. This method of accounting for the PCI – other loans from the North Valley Bancorp acquisition is often referred to as the “cost recovery” method of income recognition.
	The following table presents a reconciliation of the undiscounted contractual cash flows, nonaccretable difference, accretable yield, fair value, purchase discount, and principal balance of loans for the PNCI and PCI – other categories of North Valley Bancorp loans as of the acquisition date. For North Valley Bancorp PCI – other loans, the purchase discount does not necessarily represent cash flows to be collected:
		North Valley Bancorp Loans – October 3, 2014
	(in thousands)	PNCI			PCI – other			Total
	Undiscounted contractual cash flows	$	718,731		$	15,706		$	734,437
	Undiscounted cash flows not expected to be collected (nonaccretable difference)		—			(6,295	)		(6,295	)
Undiscounted cash flows expected to be collected		718,731			9,411			728,142
Accretable yield at acquisition		(228,815	)		—			(228,815	)
Estimated fair value of loans acquired at acquisition		489,916			9,411			499,327
Purchase discount		12,721			2,077			14,798
Principal balance loans acquired	$	502,637		$	11,488		$	514,125
As part of the acquisition of North Valley Bancorp, the Company performed a valuation of premises and equipment acquired. This valuation resulted in a $4,785,000 increase in the net book value of land and buildings acquired, and was based on current appraisals of such land and buildings.
The Company recognized a core deposit intangible of $6,614,000 related to the acquisition of North Valley Bancorp’s core deposits. The recorded core deposit intangibles represented approximately 0.97% of core deposits for North Valley Bancorp and will be amortized over their useful lives of 7 years.
A valuation of time deposits for North Valley Bancorp was also performed as of the acquisition date. Time deposits were split into similar pools based on size, type of time deposits, and maturity. A discounted cash flow analysis was performed on the pools based on current market rates currently paid on similar time deposits. The valuation resulted in no material fair value discount or premium, and none was recorded.
The fair value of junior subordinated debentures assumed from North Valley Bancorp was estimated using a discounted cash flow method based on the current market rates for similar liabilities. As a result a discount of $6,664,000 was recorded on the junior subordinated debentures acquired from North Valley Bancorp. The discount on the subordinated debentures will be amortized using the effective yield method the remaining life to maturity of the debentures at acquisition which range from 18 years to 21 years.

Investment_Securities

Investment Securities	3 Months Ended
	Mar. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Note 3 – Investment Securities
	The amortized cost and estimated fair values of investments in debt and equity securities are summarized in the following tables:
		March 31, 2015
		Amortized		Gross			Gross			Estimated
		Cost		Unrealized			Unrealized			Fair
				Gains			Losses			Value
		(in thousands)
	Securities Available for Sale
	Obligations of U.S. government corporations and agencies	$	206,476	$	4,221		$	(162	)	$	210,535
	Obligations of states and political subdivisions		9,700		36			(80	)		9,656
	Corporate debt securities		1,895		10			—			1,905
	Marketable equity securities		3,000		30			—			3,030
	Total securities available for sale	$	221,071	$	4,297		$	(242	)	$	225,126
	Securities Held to Maturity
	Obligations of U.S. government corporations and agencies	$	786,889	$	15,726		$	(339	)	$	802,276
	Obligations of states and political subdivisions		15,593		95			(171	)		15,517
	Total securities held to maturity	$	802,482	$	15,821		$	(510	)	$	817,793
		December 31, 2014
		Amortized		Gross			Gross			Estimated
		Cost		Unrealized			Unrealized			Fair
				Gains			Losses			Value
		(in thousands)
	Securities Available for Sale
	Obligations of U.S. government corporations and agencies	$	71,144	$	4,001		$	(25	)	$	75,120
	Obligations of states and political subdivisions		3,130		45			—			3,175
	Corporate debt securities		1,891		17			—			1,908
	Marketable equity securities		3,000		2			—			3,002
	Total securities available for sale	$	79,165	$	4,065		$	(25	)	$	83,205
	Securities Held to Maturity
	Obligations of U.S. government corporations and agencies	$	660,836	$	13,055		$	(677	)	$	673,214
	Obligations of states and political subdivisions		15,590		130			(155	)		15,565
	Total securities held to maturity	$	676,426	$	13,185		$	(832	)	$	688,779
	No investment securities were sold during the three months ended March 31, 2015 or the three months ended March 31, 2014. Investment securities with an aggregate carrying value of $153,121,000 and $143,992,000 at March 31, 2015 and December 31, 2014, respectively, were pledged as collateral for specific borrowings, lines of credit and local agency deposits.
	The amortized cost and estimated fair value of debt securities at March 31, 2015 by contractual maturity are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. At March 31, 2015, obligations of U.S. government corporations and agencies with a cost basis totaling $993,365,000 consist almost entirely of mortgage-backed securities whose contractual maturity, or principal repayment, will follow the repayment of the underlying mortgages. For purposes of the following table, the entire outstanding balance of these mortgage-backed securities issued by U.S. government corporations and agencies is categorized based on final maturity date. At March 31, 2015, the Company estimates the average remaining life of these mortgage-backed securities issued by U.S. government corporations and agencies to be approximately 5.2 years. Average remaining life is defined as the time span after which the principal balance has been reduced by half.
	Investment Securities	Available for Sale					Held to Maturity
	(In thousands)	Amortized		Estimated			Amortized			Estimated
		Cost		Fair Value			Cost			Fair Value
	Due in one year	$	1,896	$	1,906			—			—
	Due after one year through five years		4,014		4,202			—			—
	Due after five years through ten years		31,848		33,332		$	1,125		$	1,134
	Due after ten years		183,313		185,686			801,357			816,659
	Totals	$	221,071	$	225,126		$	802,482		$	817,793
	Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows:
		Less than 12 months					12 months or more						Total
		Fair		Unrealized			Fair			Unrealized			Fair		Unrealized
		Value		Loss			Value			Loss			Value		Loss
		(in thousands)
	March 31, 2015
	Securities Available for Sale:
	Obligations of U.S. government corporations and agencies	$	78,146	$	(162	)		—			—		$	78,146	$	(162	)
	Obligations of states and political subdivisions		6,422		(80	)		—			—			6,422		(80	)
	Corporate debt securities		—		—			—			—			—		—
	Marketable equity securities		—		—			—			—			—		—
	Total securities available-for-sale	$	84,568	$	(242	)		—			—		$	84,568	$	(242	)
	Securities Held to Maturity:
	Obligations of U.S. government corporations and agencies	$	162,549	$	(339	)		—			—		$	162,549	$	(339	)
	Obligations of states and political subdivisions		2,419		(27	)	$	1,075		$	(144	)		3,494		(171	)
	Corporate debt securities		—		—			—			—			—		—
	Total securities held-to-maturity	$	164,968	$	(366	)	$	1,075		$	(144	)	$	166,043	$	(510	)
		Less than 12 months					12 months or more						Total
		Fair		Unrealized			Fair			Unrealized			Fair		Unrealized
		Value		Loss			Value			Loss			Value		Loss
		(in thousands)
	December 31, 2014
Securities Available for Sale:
Obligations of U.S. government corporations and agencies	$	6,774	$	(25	)		—			—		$	6,774	$	(25	)
Obligations of states and political subdivisions		—		—			—			—			—		—
Corporate debt securities		—		—			—			—			—		—
Marketable equity securities		—		—			—			—			—		—
Total securities available-for-sale	$	6,774	$	(25	)		—			—		$	6,774	$	(25	)
Securities Held to Maturity:
Obligations of U.S. government corporations and agencies	$	335	$	(1	)	$	56,288		$	(676	)	$	56,623	$	(677	)
Obligations of states and political subdivisions		1,600		(26	)		1,858			(129	)		3,458		(155	)
Corporate debt securities		—		—			—			—			—		—
Total securities held-to-maturity	$	1,935	$	(27	)	$	58,146		$	(805	)	$	60,081	$	(832	)
Obligations of U.S. government corporations and agencies: Unrealized losses on investments in obligations of U.S. government corporations and agencies are caused by interest rate increases. The contractual cash flows of these securities are guaranteed by U.S. Government Sponsored Entities (principally Fannie Mae and Freddie Mac). It is expected that the securities would not be settled at a price less than the amortized cost of the investment. Because the decline in fair value is attributable to changes in interest rates and not credit quality, and because the Company does not intend to sell and more likely than not will not be required to sell, these investments are not considered other-than-temporarily impaired. At March 31, 2015, 14 debt securities representing obligations of U.S. government corporations and agencies had unrealized losses with aggregate depreciation of (0.21%) from the Company’s amortized cost basis.
Obligations of states and political subdivisions: The unrealized losses on investments in obligations of states and political subdivisions were caused by increases in required yields by investors in these types of securities. It is expected that the securities would not be settled at a price less than the amortized cost of the investment. Because the decline in fair value is attributable to changes in interest rates and not credit quality, and because the Company does not intend to sell and more likely than not will not be required to sell, these investments are not considered other-than-temporarily impaired. At March 31, 2015, 13 debt securities representing obligations of states and political subdivisions had unrealized losses with aggregate depreciation of (2.48%) from the Company’s amortized cost basis.
Corporate debt securities: At March 31, 2015, no corporate debt securities had unrealized losses.
Marketable equity securities: At March 31, 2015, no marketable equity securities had unrealized losses.

Loans

Loans	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
Loans	Note 4 – Loans
	A summary of loan balances follows (in thousands):
		March 31, 2015
		Originated			PNCI			PCI -			PCI -			Total
								Cash basis			Other
	Mortgage loans on real estate:
	Residential 1-4 family	$	160,041		$	118,316			—		$	4,026		$	282,383
	Commercial		970,433			366,096			—			27,951			1,364,480
	Total mortgage loan on real estate		1,130,474			484,412			—			31,977			1,646,863
	Consumer:
	Home equity lines of credit		299,298			36,953			5,459			3,500			345,210
	Home equity loans		26,892			4,841			124			629			32,486
	Auto Indirect		32			—			—			—			32
	Other		28,740			4,189			—			70			32,999
	Total consumer loans		354,962			45,983			5,583			4,199			410,727
	Commercial		134,055			36,429			6			7,050			177,540
	Construction:
	Residential		23,664			15,705			—			736			40,105
	Commercial		32,558			13,090			—			—			45,648
	Total construction		56,222			28,795			—			736			85,753
	Total loans, net of deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Total principal balance of loans owed, net of charge-offs	$	1,680,523		$	612,382		$	14,592		$	51,785		$	2,359,282
	Unamortized net deferred loan fees		(4,810	)		—			—			—			(4,810	)
	Discounts to principal balance of loans owed, net of charge-offs		—			(16,763	)		(9,003	)		(7,823	)		(33,589	)
	Total loans, net of unamortized deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Noncovered loans	$	1,675,713		$	595,619		$	5,589		$	23,542		$	2,300,463
	Covered loans		—			—			—			20,420			20,420
	Total loans, net of unamortized deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Allowance for loan losses	$	(30,032	)	$	(2,925	)	$	(340	)	$	(2,758	)	$	(36,055	)
	A summary of loan balances follows (in thousands):
		December 31, 2014
		Originated			PNCI			PCI -			PCI -			Total
								Cash basis			Other
	Mortgage loans on real estate:
	Residential 1-4 family	$	154,594		$	120,821			—		$	4,005		$	279,420
	Commercial		928,797			376,225			—			30,917			1,335,939
	Total mortgage loan on real estate		1,083,391			497,046			—			34,922			1,615,359
	Consumer:
	Home equity lines of credit		305,166			38,397		$	5,478			3,543			352,584
	Home equity loans		23,559			6,985			125			645			31,314
	Auto Indirect		112			—			—			—			112
	Other		28,230			4,770			—			74			33,074
	Total consumer loans		357,067			50,152			5,603			4,262			417,084
	Commercial		126,611			40,899			8			7,427			174,945
	Construction:
	Residential		21,135			16,808			—			675			38,618
	Commercial		24,545			11,973			—			—			36,518
	Total construction		45,680			28,781			—			675			75,136
	Total loans, net of deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Total principal balance of loans owed, net of charge-offs	$	1,617,542		$	634,490		$	14,805		$	56,016		$	2,322,853
	Unamortized net deferred loan fees		(4,793	)		—			—			—			(4,793	)
	Discounts to principal balance of loans owed, net of charge-offs		—			(17,612	)		(9,194	)		(8,730	)		(35,536	)
	Total loans, net of unamortized deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Noncovered loans	$	1,612,749		$	616,878		$	5,611		$	25,018		$	2,260,256
	Covered loans		—			—			—			22,268			22,268
	Total loans, net of unamortized deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Allowance for loan losses	$	(29,860	)	$	(3,296	)	$	(348	)	$	(3,081	)	$	(36,585	)
	The following is a summary of the change in accretable yield for PCI – other loans during the periods indicated (in thousands):
		Three months ended March 31,
		2015			2014
	Change in accretable yield:
	Balance at beginning of period	$	14,159		$	18,232
	Accretion to interest income		(1,818	)		(1,631	)
	Reclassification (to) from nonaccretable difference		1,061			837
Balance at end of period	$	13,402		$	17,438

Allowance_for_Loan_Losses

Allowance for Loan Losses	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
Allowance for Loan Losses	Note 5 – Allowance for Loan Losses
	The following tables summarize the activity in the allowance for loan losses, and ending balance of loans, net of unearned fees for the periods indicated.
			Allowance for Loan Losses – Year Ended March 31, 2015
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance		$	3,086		$	9,227		$	15,676		$	1,797		$	9		$	719		$	4,226		$	1,434		$	411		$	36,585
	Charge-offs			(81	)		—			(341	)		(11	)		—			(268	)		(534	)		—			—			(1,235	)
	Recoveries			1			96			119			3			20			152			87			11			19			508
	(Benefit) provision			(241	)		1,128			(221	)		191			(23	)		41			197			(695	)		(180	)		197
	Ending balance		$	2,765		$	10,451		$	15,233		$	1,980		$	6		$	644		$	3,976		$	750		$	250		$	36,055
	Ending balance:
	Individ. evaluated for impairment		$	988		$	799		$	1,857		$	337		$	1		$	92		$	559		$	59			—		$	4,692
	Loans pooled for evaluation		$	1,709		$	8,464		$	12,932		$	1,643		$	5		$	552		$	2,205		$	505		$	250		$	28,265
	Loans acquired with deteriorated credit quality		$	69		$	1,188		$	443			—			—			—		$	1,212		$	186			—		$	3,098
			Loans, net of unearned fees – As of March 31, 2015
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans		$	282,383		$	1,364,480		$	345,210		$	32,486		$	32		$	32,999		$	177,540		$	40,105		$	45,648		$	2,320,883
	Individ. evaluated for impairment		$	7,786		$	44,523		$	6,290		$	1,359		$	14		$	338		$	1,967		$	2,655		$	94		$	65,026
	Loans pooled for evaluation		$	270,571		$	1,292,006		$	329,961		$	30,374		$	18		$	32,591		$	168,517		$	36,714		$	45,554		$	2,206,306
	Loans acquired with deteriorated credit quality		$	4,026		$	27,951		$	8,959		$	753			—		$	70		$	7,056		$	736			—		$	49,551
			Allowance for Loan Losses – Year Ended December 31, 2014
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance		$	3,154		$	9,700		$	16,375		$	1,208		$	66		$	589		$	4,331		$	1,559		$	1,263		$	38,245
	Charge-offs			(171	)		(110	)		(1,094	)		(29	)		(3	)		(599	)		(479	)		(4	)		(69	)		(2,558	)
	Recoveries			2			540			960			34			86			495			1,268			1,377			181			4,943
	(Benefit) provision			101			(903	)		(565	)		584			(140	)		234			(894	)		(1,498	)		(964	)		(4,045	)
	Ending balance		$	3,086		$	9,227		$	15,676		$	1,797		$	9		$	719		$	4,226		$	1,434		$	411		$	36,585
	Ending balance:
	Individ. evaluated for impairment		$	974		$	410		$	1,974		$	284			—		$	142		$	423		$	60			—		$	4,267
	Loans pooled for evaluation		$	1,915		$	8,408		$	13,251		$	1,513		$	9		$	572		$	2,569		$	332		$	322		$	28,891
	Loans acquired with deteriorated credit quality		$	197		$	409		$	451			—			—		$	5		$	1,234		$	1,042		$	89		$	3,427
			Loans, net of unearned fees – As of December 31, 2014
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans		$	279,420		$	1,335,939		$	352,584		$	31,314		$	112		$	33,074		$	174,945		$	38,618		$	35,518		$	2,282,524
	Individ. evaluated for impairment		$	7,188		$	41,932		$	6,968		$	1,278		$	18		$	323		$	1,757		$	2,683		$	99		$	62,246
	Loans pooled for evaluation		$	268,227		$	1,263,090		$	336,595		$	29,266		$	94		$	32,677		$	165,753		$	35,260		$	36,419		$	2,167,381
	Loans acquired with deteriorated credit quality		$	4,005		$	30,917		$	9,021		$	770			—		$	74		$	7,435		$	675			—		$	52,897
			Allowance for Loan Losses – Three Months Ended March 31, 2014
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance		$	3,154		$	9,700		$	16,375		$	1,208		$	66		$	589		$	4,331		$	1,559		$	1,263		$	38,245
	Charge-offs			(135	)		(13	)		(178	)		—			—			(127	)		(239	)		(4	)		(69	)		(765	)
	Recoveries			—			172			329			2			12			183			873			511			115			2,197
	(Benefit) provision			(39	)		16			(160	)		81			(33	)		(55	)		(829	)		(565	)		229			(1,355	)
	Ending balance		$	2,980		$	9,875		$	16,366		$	1,291		$	45		$	590		$	4,136		$	1,501		$	1,538		$	38,322
	Ending balance:
	Individ. evaluated for impairment		$	666		$	968		$	1,394		$	178		$	1		$	4		$	626		$	104			—		$	3,941
	Loans pooled for evaluation		$	1,962		$	8,129		$	14,489		$	1,113		$	44		$	586		$	2,194		$	769		$	1,033		$	30,319
	Loans acquired with deteriorated credit quality		$	352		$	778		$	484			—			—			—		$	1,316		$	627		$	505		$	4,062
			Loans, net of unearned fees – As of March 31, 2014
			RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans		$	195,826		$	930,472		$	337,802		$	15,776		$	575		$	27,633		$	119,418		$	37,394		$	22,156		$	1,687,052
	Individ. evaluated for impairment		$	7,322		$	59,613		$	7,091		$	774		$	49		$	101		$	2,537		$	2,793		$	19		$	80,299
	Loans pooled for evaluation		$	184,002		$	840,642		$	320,846		$	14,522		$	526		$	27,457		$	110,602		$	33,153		$	22,081		$	1,553,831
	Loans acquired with deteriorated credit quality		$	4,502		$	30,217		$	9,865		$	480			—		$	75		$	6,279		$	1,448		$	56		$	52,922
	As part of the on-going monitoring of the credit quality of the Company’s loan portfolio, management tracks certain credit quality indicators including, but not limited to, trends relating to (i) the level of criticized and classified loans, (ii) net charge-offs, (iii) non-performing loans, and (iv) delinquency within the portfolio.
	The Company utilizes a risk grading system to assign a risk grade to each of its loans. Loans are graded on a scale ranging from Pass to Loss. A description of the general characteristics of the risk grades is as follows:
	•		Pass – This grade represents loans ranging from acceptable to very little or no credit risk. These loans typically meet most if not all policy standards in regard to: loan amount as a percentage of collateral value, debt service coverage, profitability, leverage, and working capital.
	•		Special Mention – This grade represents “Other Assets Especially Mentioned” in accordance with regulatory guidelines and includes loans that display some potential weaknesses which, if left unaddressed, may result in deterioration of the repayment prospects for the asset or may inadequately protect the Company’s position in the future. These loans warrant more than normal supervision and attention.
	•		Substandard – This grade represents “Substandard” loans in accordance with regulatory guidelines. Loans within this rating typically exhibit weaknesses that are well defined to the point that repayment is jeopardized. Loss potential is, however, not necessarily evident. The underlying collateral supporting the credit appears to have sufficient value to protect the Company from loss of principal and accrued interest, or the loan has been written down to the point where this is true. There is a definite need for a well defined workout/rehabilitation program.
	•		Doubtful – This grade represents “Doubtful” loans in accordance with regulatory guidelines. An asset classified as Doubtful has all the weaknesses inherent in a loan classified Substandard with the added characteristic that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable. Pending factors include proposed merger, acquisition, or liquidation procedures, capital injection, perfecting liens on additional collateral, and financing plans.
	•		Loss – This grade represents “Loss” loans in accordance with regulatory guidelines. A loan classified as Loss is considered uncollectible and of such little value that its continuance as a bankable asset is not warranted. This classification does not mean that the loan has absolutely no recovery or salvage value, but rather that it is not practical or desirable to defer writing off the loan, even though some recovery may be affected in the future. The portion of the loan that is graded loss should be charged off no later than the end of the quarter in which the loss is identified.
The following tables present ending loan balances by loan category and risk grade for the periods indicated:
		Credit Quality Indicators – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Originated loans:
Pass		$	152,273		$	926,236		$	286,624		$	24,010			—		$	28,010		$	132,590		$	20,498		$	31,877		$	1,602,118
Special mention			1,315			11,795			3,641			891		$	6			487			757			793			584			20,269
Substandard			6,453			32,402			9,033			1,991			26			243			708			2,373			97			53,326
Loss			—			—			—			—			—			—			—			—			—			—
Total originated		$	160,041		$	970,433		$	299,298		$	26,892		$	32		$	28,740		$	134,055		$	23,664		$	32,558		$	1,675,713
PNCI loans:
Pass		$	116,888		$	348,541		$	34,903		$	4,662			—		$	3,914		$	36,128		$	15,705		$	13,090		$	573,831
Special mention			680			12,874			935			105			—			123			5			—			—			14,722
Substandard			748			4,681			1,115			74			—			152			296			—			—			7,066
Loss			—			—			—			—			—			—			—			—			—			—
Total PNCI		$	118,316		$	366,096		$	36,953		$	4,841			—		$	4,189		$	36,429		$	15,705		$	13,090		$	595,619
PCI loans		$	4,026		$	27,951		$	8,959		$	753			—		$	70		$	7,056		$	736			—		$	49,551
Total loans		$	282,383			1,364,480		$	345,210		$	32,486		$	32		$	32,999		$	177,540		$	40,105		$	45,648		$	2,320,883
		Credit Quality Indicators – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Originated loans:
Pass		$	146,949		$	883,102		$	292,244		$	20,976		$	66		$	27,396		$	124,707		$	18,112		$	24,436		$	1,537,988
Special mention			1,122			11,521			3,590			743			11			591			636			622			—			18,836
Substandard			6,523			34,174			9,332			1,840			35			243			1,268			2,401			109			55,925
Loss			—			—			—			—			—			—			—			—			—			—
Total originated		$	154,594		$	928,797		$	305,166		$	23,559		$	112		$	28,230		$	126,611		$	21,135		$	24,545		$	1,612,749
PNCI loans:
Pass		$	119,643		$	359,537		$	36,531		$	6,813			—		$	4,399		$	40,628		$	16,808		$	11,973		$	596,332
Special mention			547			12,979			936			147			—			230			268			—			—			15,107
Substandard			631			3,709			930			25			—			141			3			—			—			5,439
Loss			—			—			—			—			—			—			—			—			—			—
Total PNCI		$	120,821		$	376,225		$	38,397		$	6,985			—		$	4,770		$	40,899		$	16,808		$	11,973		$	616,878
PCI loans		$	4,005		$	30,917		$	9,021		$	770			—		$	74		$	7,435		$	675			—		$	52,897
Total loans		$	279,420		$	1,335,939		$	352,584		$	31,314		$	112		$	33,074		$	174,945		$	38,618		$	36,518		$	2,282,524
Consumer loans, whether unsecured or secured by real estate, automobiles, or other personal property, are susceptible to three primary risks; non-payment due to income loss, over-extension of credit and, when the borrower is unable to pay, shortfall in collateral value. Typically non-payment is due to loss of job and will follow general economic trends in the marketplace driven primarily by rises in the unemployment rate. Loss of collateral value can be due to market demand shifts, damage to collateral itself or a combination of the two.
Problem consumer loans are generally identified by payment history of the borrower (delinquency). The Bank manages its consumer loan portfolios by monitoring delinquency and contacting borrowers to encourage repayment, suggest modifications if appropriate, and, when continued scheduled payments become unrealistic, initiate repossession or foreclosure through appropriate channels. Collateral values may be determined by appraisals obtained through Bank approved, licensed appraisers, qualified independent third parties, public value information (blue book values for autos), sales invoices, or other appropriate means. Appropriate valuations are obtained at initiation of the credit and periodically (every 3-12 months depending on collateral type) once repayment is questionable and the loan has been classified.
Commercial real estate loans generally fall into two categories, owner-occupied and non-owner occupied. Loans secured by owner occupied real estate are primarily susceptible to changes in the business conditions of the related business. This may be driven by, among other things, industry changes, geographic business changes, changes in the individual fortunes of the business owner, and general economic conditions and changes in business cycles. These same risks apply to commercial loans whether secured by equipment or other personal property or unsecured. Losses on loans secured by owner occupied real estate, equipment, or other personal property generally are dictated by the value of underlying collateral at the time of default and liquidation of the collateral. When default is driven by issues related specifically to the business owner, collateral values tend to provide better repayment support and may result in little or no loss. Alternatively, when default is driven by more general economic conditions, underlying collateral generally has devalued more and results in larger losses due to default. Loans secured by non-owner occupied real estate are primarily susceptible to risks associated with swings in occupancy or vacancy and related shifts in lease rates, rental rates or room rates. Most often these shifts are a result of changes in general economic or market conditions or overbuilding and resultant over-supply. Losses are dependent on value of underlying collateral at the time of default. Values are generally driven by these same factors and influenced by interest rates and required rates of return as well as changes in occupancy costs.
Construction loans, whether owner occupied or non-owner occupied commercial real estate loans or residential development loans, are not only susceptible to the related risks described above but the added risks of construction itself including cost over-runs, mismanagement of the project, or lack of demand or market changes experienced at time of completion. Again, losses are primarily related to underlying collateral value and changes therein as described above.
Problem C&I loans are generally identified by periodic review of financial information which may include financial statements, tax returns, rent rolls and payment history of the borrower (delinquency). Based on this information the Bank may decide to take any of several courses of action including demand for repayment, additional collateral or guarantors, and, when repayment becomes unlikely through borrower’s income and cash flow, repossession or foreclosure of the underlying collateral.
Collateral values may be determined by appraisals obtained through Bank approved, licensed appraisers, qualified independent third parties, public value information (blue book values for autos), sales invoices, or other appropriate means. Appropriate valuations are obtained at initiation of the credit and periodically (every 3-12 months depending on collateral type) once repayment is questionable and the loan has been classified.
Once a loan becomes delinquent and repayment becomes questionable, a Bank collection officer will address collateral shortfalls with the borrower and attempt to obtain additional collateral. If this is not forthcoming and payment in full is unlikely, the Bank will estimate its probable loss, using a recent valuation as appropriate to the underlying collateral less estimated costs of sale, and charge the loan down to the estimated net realizable amount. Depending on the length of time until ultimate collection, the Bank may revalue the underlying collateral and take additional charge-offs as warranted. Revaluations may occur as often as every 3-12 months depending on the underlying collateral and volatility of values. Final charge-offs or recoveries are taken when collateral is liquidated and actual loss is known. Unpaid balances on loans after or during collection and liquidation may also be pursued through lawsuit and attachment of wages or judgment liens on borrower’s other assets.
The following table shows the ending balance of current, past due, and nonaccrual originated loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual Originated Loans – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Originated loan balance:
Past due:
30-59 Days		$	1,225		$	545		$	1,689		$	140		$	2		$	5		$	318			—			—		$	3,924
60-89 Days			—			714			285			276			—			5			35			—			—			1,315
> 90 Days			629			1,028			565			390			14			59			24			—			—			2,709
Total past due		$	1,854		$	2,287		$	2,539		$	806		$	16		$	69		$	377			—			—		$	7,948
Current			158,187			968,146			296,759			26,086			16			28,671			133,678			23,664			32,558			1,667,765
Total orig. loans		$	160,041		$	970,433		$	299,298		$	26,892		$	32		$	28,740		$	134,055		$	23,664		$	32,558		$	1,675,713
> 90 Days and still accruing		$	328			—			—			—			—			—			—			—			—		$	328
Nonaccrual loans		$	4,111		$	22,486		$	3,700		$	1,217		$	14		$	62		$	191		$	2,373		$	94		$	34,248
The following table shows the ending balance of current, past due, and nonaccrual PNCI loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual PNCI Loans – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
PNCI loan balance:
Past due:
30-59 Days		$	1,401		$	560		$	69			—			—		$	28			—			—			—		$	2,058
60-89 Days			—			75			395			43			—			1			—			—			—			514
> 90 Days			121			—			38			25			—			31			—			—			—			215
Total past due		$	1,522		$	635		$	502		$	68			—		$	60			—			—			—		$	2,787
Current			116,832			365,461			36,220			4,966			—			4,129			36,429			15,705			13,090			592,832
Total PNCI loans		$	118,354		$	366,096		$	36,722		$	5,034			—		$	4,189		$	36,429		$	15,705		$	13,090		$	595,619
> 90 Days and still accruing			—			—			—			—			—			—			—			—			—			—
Nonaccrual loans		$	728		$	1,003		$	414		$	25			—		$	66			—			—			—		$	2,236
The following table shows the ending balance of current, past due, and nonaccrual originated loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual Originated Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Originated loan balance:
Past due:
30-59 Days		$	1,296		$	735		$	2,066		$	615		$	4		$	64		$	739			—			—		$	5,519
60-89 Days			919			—			296			192			—			24			99			—			—			1,530
> 90 Days			100			900			754			202			17			46			61			—			—			2,080
Total past due		$	2,315		$	1,635		$	3,116		$	1,009		$	21		$	134		$	899			—			—		$	9,129
Current			152,279			927,162			302,050			22,550			91			28,096			125,712			21,135			24,545			1,603,620
Total orig. loans		$	154,594		$	928,797		$	305,166		$	23,559		$	112		$	28,230		$	126,611		$	21,135		$	24,545		$	1,612,749
> 90 Days and still accruing			—			—			—			—			—			—			—			—			—			—
Nonaccrual loans		$	3,430		$	20,736		$	4,336		$	1,197		$	18		$	66		$	246		$	2,401		$	99		$	32,529
The following table shows the ending balance of current, past due, and nonaccrual PNCI loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual PNCI Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
PNCI loan balance:
Past due:
30-59 Days		$	2,041		$	260		$	275			—			—		$	25		$	67			—			—		$	2,668
60-89 Days			24			—			118			—			—			3			—			—			—			145
> 90 Days			239			—			73			25			—			76			—			—			—			413
Total past due		$	2,304		$	260		$	466		$	25			—		$	104		$	67			—			—		$	3,226
Current			118,517			375,965			37,931			6,960			—			4,666			40,832			16,808			11,973		$	613,652
Total PNCI loans		$	120,821		$	376,225		$	38,397		$	6,985			—		$	4,770		$	40,899		$	16,808		$	11,973		$	616,878
> 90 Days and still accruing			—			—			—			—			—			—			—			—			—			—
Nonaccrual loans		$	799		$	366		$	346		$	25			—		$	110			—			—			—		$	1,646
Impaired originated loans are those where management has concluded that it is probable that the borrower will be unable to pay all amounts due under the contractual terms. The following tables show the recorded investment (financial statement balance), unpaid principal balance, average recorded investment, and interest income recognized for impaired Originated and PNCI loans, segregated by those with no related allowance recorded and those with an allowance recorded for the periods indicated.
		Impaired Originated Loans – As of, or for the Three Months Ended, March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	3,360		$	40,094		$	2,631		$	870		$	10		$	19		$	748		$	2,373		$	94		$	50,199
Unpaid principal		$	5,330		$	43,898		$	5,791		$	1,335		$	30		$	23		$	776		$	6,585		$	186		$	63,954
Average recorded Investment		$	3,323		$	39,286		$	2,816		$	810		$	12		$	22		$	580		$	2,387		$	96		$	49,332
Interest income Recognized		$	8		$	283			—			—			—			—		$	11			—			—		$	302
With an allowance recorded:
Recorded investment		$	3,402		$	3,281		$	2,808		$	464		$	4		$	43		$	1,214		$	282			—		$	11,498
Unpaid principal		$	3,570		$	3,432		$	3,077		$	566		$	6		$	53		$	1,316		$	282			—		$	12,302
Related allowance		$	915		$	598		$	1,636		$	337		$	1		$	17		$	559		$	59			—		$	4,122
Average recorded Investment		$	3,063		$	3,112		$	2,997		$	484		$	4		$	42		$	1,276		$	282			—		$	11,260
Interest income Recognized		$	22		$	40		$	12		$	1			—			—		$	15		$	4			—		$	94
		Impaired PNCI Loans – As of, or for the Three Months Ended, March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	389		$	313		$	414		$	25			—		$	59		$	5			—			—		$	1,205
Unpaid principal		$	488		$	2,601		$	450		$	25			—		$	78		$	5			—			—		$	3,647
Average recorded Investment		$	366		$	339		$	380		$	25			—		$	48		$	6			—			—		$	1,164
Interest income Recognized		$	1			—			—			—			—			—			—			—			—		$	1
With an allowance recorded:
Recorded investment		$	635		$	835		$	437			—			—		$	217			—			—			—		$	2,124
Unpaid principal		$	644		$	838		$	437			—			—		$	217			—			—			—		$	2,136
Related allowance		$	73		$	201		$	221			—			—		$	75			—			—			—		$	570
Average recorded Investment		$	734		$	490		$	436			—			—		$	219			—			—			—		$	1,879
Interest income Recognized		$	2		$	10		$	4			—			—		$	2			—			—			—		$	18
		Impaired Originated Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	3,287		$	38,477		$	3,001		$	750		$	14		$	25		$	412		$	2,401		$	99		$	48,466
Unpaid principal		$	5,138		$	41,949		$	6,094		$	1,187		$	49		$	32		$	433		$	6,588		$	190		$	61,660
Average recorded Investment		$	3,826		$	45,915		$	3,355		$	651		$	35		$	21		$	1,030		$	2,437		$	84		$	57,354
Interest income Recognized		$	38		$	995		$	26		$	6			—		$	1		$	26			—		$	3		$	1,095
With an allowance recorded:
Recorded investment		$	2,724		$	2,943		$	3,185		$	504		$	4		$	41		$	1,338		$	282			—		$	11,021
Unpaid principal		$	2,865		$	3,101		$	3,533		$	597		$	6		$	41		$	1,438		$	282			—		$	11,863
Related allowance		$	797		$	302		$	1,769		$	284			—		$	11		$	423		$	60			—		$	3,646
Average recorded Investment		$	2,677		$	4,119		$	2,982		$	365		$	4		$	25		$	1,428		$	283		$	55		$	11,938
Interest income Recognized		$	91		$	144		$	71		$	13			—			—		$	71		$	19			—		$	409
		Impaired PNCI Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	343		$	366		$	346		$	25			—		$	37		$	7			—			—		$	1,124
Unpaid principal		$	353		$	2,620		$	374		$	25			—		$	54		$	7			—			—		$	3,433
Average recorded Investment		$	246		$	753		$	287		$	12			—		$	36		$	10			—			—		$	1,344
Interest income Recognized		$	14			—		$	(1	)		—			—			—		$	1			—			—		$	14
With an allowance recorded:
Recorded investment		$	834		$	146		$	436			—			—		$	220			—			—			—		$	1,636
Unpaid principal		$	852		$	146		$	436			—			—		$	220			—			—			—		$	1,654
Related allowance		$	177		$	108		$	205			—			—		$	131			—			—			—		$	621
Average recorded Investment		$	516		$	148		$	319			—			—		$	124			—			—			—		$	1,107
Interest income Recognized		$	8		$	8		$	20			—			—		$	12			—			—			—		$	48
		Impaired Originated Loans – As of, or for the Three Months Ended, March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	4,349		$	53,996		$	3,386		$	541		$	45		$	32		$	1,105		$	87		$	19		$	63,560
Unpaid principal		$	6,532		$	59,159		$	6,833		$	921		$	82		$	37		$	1,120		$	225		$	101		$	75,010
Average recorded Investment		$	4,206		$	57,403		$	3,972		$	483		$	66		$	21		$	1,370		$	1,415		$	39		$	68,975
Interest income Recognized		$	14		$	340		$	2			—			—			—		$	15			—			—		$	371
With an allowance recorded:
Recorded investment		$	2,457		$	4,599		$	3,214		$	234		$	4		$	5		$	1,421		$	2,707			—		$	14,641
Unpaid principal		$	2,528		$	5,240		$	3,449		$	300		$	5		$	6		$	1,509		$	6,773			—		$	19,810
Related allowance		$	502		$	855		$	1,228		$	178		$	1		$	1		$	626		$	104			—		$	3,495
Average recorded Investment		$	2,353		$	5,773		$	3,057		$	170		$	7		$	7		$	1,766		$	1,497		$	151		$	14,781
Interest income Recognized		$	13		$	25		$	14		$	1			—			—		$	13		$	5			—		$	71
		Impaired PNCI Loans – As of, or for the Three Months Ended, March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment		$	84		$	870		$	326			—			—		$	34		$	11			—			—		$	1,325
Unpaid principal		$	84		$	3,044		$	336			—			—		$	45		$	11			—			—		$	3,520
Average recorded Investment		$	58		$	905		$	339			—			—		$	37		$	9			—			—		$	1,348
Interest income Recognized		$	2			—		$	6			—			—			—			—			—			—		$	8
With an allowance recorded:
Recorded investment		$	432		$	148		$	166			—			—		$	28			—			—			—		$	774
Unpaid principal		$	443		$	149		$	172			—			—		$	28			—			—			—		$	792
Related allowance		$	164		$	113		$	166			—			—		$	3			—			—			—		$	446
Average recorded Investment		$	334		$	157		$	195			—			—		$	28			—			—			—		$	714
Interest income Recognized		$	2		$	2			—			—			—			—			—			—			—		$	4
At March 31, 2015, $45,641,000 of originated loans were TDR and classified as impaired. The Company had obligations to lend $4,000 of additional funds on these TDR as of March 31, 2015. At March 31, 2015, $1,231,000 of PNCI loans were TDR and classified as impaired. The Company had no obligations to lend additional funds on these TDR as of March 31, 2015.
At December 31, 2014, $45,676,000 of Originated loans were TDRs and classified as impaired. The Company had obligations to lend $54,000 of additional funds on these TDRs as of December 31, 2014. At December 31, 2014, $1,307,000 of PNCI loans were TDRs and classified as impaired. The Company had no obligations to lend additional funds on these TDRs as of December 31, 2014.
At March 31, 2014, $56,179,000 of originated loans were TDRs and classified as impaired. The Company had obligations to lend $1,000 of additional funds on these TDRs as of March 31, 2014. At March 31, 2014, $1,179,000 of PNCI loans were TDRs and classified as impaired. The Company had no obligations to lend additional funds on these TDRs as of March 31, 2014.
The following tables show certain information regarding Troubled Debt Restructurings (TDRs) that occurred during the periods indicated:
		TDR Information for the Three Months Ended March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Number			1			1			—			—			—			2			1			—			—			5
Pre-mod outstanding principal balance		$	108		$	124			—			—			—		$	89		$	287			—			—		$	608
Post-mod outstanding principal balance		$	110		$	124			—			—			—		$	89		$	288			—			—		$	611
Financial impact due to TDR taken as additional provision		$	8		$	(5	)		—			—			—		$	5		$	164			—			—		$	172
Number that defaulted during the period			—			—			1			—			—			—			—			—			—			1
Recorded investment of TDRs that defaulted during the period			—			—		$	47			—			—			—			—			—			—		$	47
the default of previous
TDR taken as charge-offs or additional provisions			—			—			—			—			—			—			—			—			—			—
The following tables show certain information regarding TDRs that occurred during the periods indicated:
		TDR Information for the Three Months Ended March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)		Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
Number			2			2			2			—			—			—			1			1			1			9
Pre-mod outstanding principal balance		$	695		$	256		$	279			—			—			—		$	38		$	102		$	118		$	1,488
Post-mod outstanding principal balance		$	695		$	259		$	279			—			—			—		$	38		$	85		$	100		$	1,456
Financial impact due to TDR taken as additional provision		$	37		$	9			—			—			—			—		$	18			—			—		$	64
Number that defaulted during the period			—			1			—			—			—			—			1			—			—			2
Recorded investment of TDRs that defaulted during the period			—		$	260			—			—			—			—		$	116			—			—		$	376
Financial impact due to the default of previous
TDR taken as charge-offs or additional provisions			—			—			—			—			—			—		$	(8	)		—			—		$	(8	)
Modifications classified as TDRs can include one or a combination of the following: rate modifications, term extensions, interest only modifications, either temporary or long-term, payment modifications, and collateral substitutions/additions.
For all new TDRs, an impairment analysis is conducted. If the loan is determined to be collateral dependent, any additional amount of impairment will be calculated based on the difference between estimated collectible value and the current carrying balance of the loan. This difference could result in an increased provision and is typically charged off. If the asset is determined not to be collateral dependent, the impairment is measured on the net present value difference between the expected cash flows of the restructured loan and the cash flows which would have been received under the original terms. The effect of this could result in a requirement for additional provision to the reserve. The effect of these required provisions for the period are indicated above.
Typically if a TDR defaults during the period, the loan is then considered collateral dependent and, if it was not already considered collateral dependent, an appropriate provision will be reserved or charge will be taken. The additional provisions required resulting from default of previously modified TDR’s are noted above.

Foreclosed_Assets

Foreclosed Assets	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Foreclosed Assets	Note 6 – Foreclosed Assets
	A summary of the activity in the balance of foreclosed assets follows (in thousands):
		Three months ended March 31, 2015								Three months ended March 31, 2014
		Noncovered			Covered		Total			Noncovered			Covered			Total
	Beginning balance, net	$	4,449		$	445	$	4,894		$	5,588		$	674		$	6,262
	Additions/transfers from loans		1,560			—		1,560			1,175			—			1,175
	Dispositions/sales		(495	)		—		(495	)		(4,186	)		—			(4,186	)
	Valuation adjustments		(67	)		—		(67	)		(26	)		(10	)		(36	)
	Ending balance, net	$	5,447		$	445	$	5,892		$	2,551		$	664		$	3,215
	Ending valuation allowance	$	263			—	$	263		$	111		$	10		$	121
	Ending number of foreclosed assets		29			1		30			22			4			26
	Proceeds from sale of foreclosed assets	$	806			—	$	806		$	5,413			—		$	5,413
	Gain on sale of foreclosed assets	$	311			—	$	311		$	1,227			—			1,227
	As of March 31, 2015, $1,691,000 of foreclosed residential real estate properties, all of which the Company has obtained physical possession of, are included in foreclosed assets.

Premises_and_Equipment

Premises and Equipment	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Premises and Equipment	Note 7 – Premises and Equipment
	Premises and equipment were comprised of:
		March 31,			December 31,
		2015			2014
		(In thousands)
	Land & land improvements	$	8,883		$	8,933
	Buildings		38,939			39,638
	Furniture and equipment		28,160			28,446
			75,982			77,017
	Less: Accumulated depreciation		(33,152	)		(33,570	)
			42,830			43,447
	Construction in progress		16			46
	Total premises and equipment	$	42,846		$	43,493
	Depreciation expense for premises and equipment amounted to $1,268,000 and $1,180,000 for the three months ended March 31, 2015 and 2014, respectively.

Cash_Value_of_Life_Insurance

Cash Value of Life Insurance	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Cash Value of Life Insurance	Note 8 – Cash Value of Life Insurance
	A summary of the activity in the balance of cash value of life insurance follows (in thousands):
		Three months ended March 31,
		2015		2014
	Beginning balance	$	92,337	$	52,309
	Increase in cash value of life insurance		675		397
	Ending balance	$	93,012	$	52,706
	End of period death benefit	$	165,847	$	94,999
	Number of policies owned		189		133
	Insurance companies used		14		6
	Current and former employees and directors covered		60		36
	As of March 31, 2015, the Bank was the owner and beneficiary of 189 life insurance policies, issued by 14 life insurance companies, covering 60 current and former employees and directors. These life insurance policies are recorded on the Company’s financial statements at their reported cash (surrender) values. As a result of current tax law and the nature of these policies, the Bank records any increase in cash value of these policies as nontaxable noninterest income. If the Bank decided to surrender any of the policies prior to the death of the insured, such surrender may result in a tax expense related to the life-to-date cumulative increase in cash value of the policy. If the Bank retains such policies until the death of the insured, the Bank would receive nontaxable proceeds from the insurance company equal to the death benefit of the policies. The Bank has entered into Joint Beneficiary Agreements (JBAs) with certain of the insured that for certain of the policies provide some level of sharing of the death benefit, less the cash surrender value, among the Bank and the beneficiaries of the insured upon the receipt of death benefits. See Note 15 of these condensed consolidated financial statements for additional information on JBAs.

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Note 9 – Goodwill and Other Intangible Assets
	The following table summarizes the Company’s goodwill intangible as of the dates indicated:
	(Dollar in Thousands)	March 31,			Additions		Reductions			December 31,
		2015								2014
	Goodwill	$	63,462			—		—		$	63,462
	The following table summarizes the Company’s core deposit intangibles as of the dates indicated:
	(Dollar in Thousands)	March 31,			Additions		Reductions/			Fully		December 31,
		2015					Amortization			Depreciated		2014
	Core deposit intangibles	$	8,074			—		—			—	$	8,074
	Accumulated amortization		(1,312	)		—	$	(289	)		—		(1,023	)
	Core deposit intangibles, net	$	6,762			—	$	(289	)		—	$	7,051
	The Company recorded additions to its CDI of $6,614,000 in conjunction with the North Valley Bancorp acquisition on October 3, 2014, $898,000 in conjunction with the Citizens acquisition on September 23, 2011, and $562,000 in conjunction with the Granite acquisition on May 28, 2010. The following table summarizes the Company’s estimated core deposit intangible amortization (dollars in thousands):
	Years Ended	Estimated Core Deposit
		Intangible Amortization
	2015	$	1,157
	2016		1,157
	2017		1,109
	2018		1,044
	2019		948
	Thereafter	$	1,636

Mortgage_Servicing_Rights

Mortgage Servicing Rights	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Mortgage Servicing Rights	Note 10 – Mortgage Servicing Rights
	The following tables summarize the activity in, and the main assumptions we used to determine the fair value of mortgage servicing rights (“MSRs”) for the periods indicated (dollars in thousands):
		Three months ended March 31,
		2015			2014
	Balance at beginning of period	$	7,378		$	6,165
	Additions		185			123
	Change in fair value		(506	)		(181	)
	Balance at end of period	$	7,057		$	6,107
	Contractually specified servicing fees, late fees and ancillary fees earned	$	534		$	420
	Balance of loans serviced at:
	Beginning of period	$	840,288		$	680,197
	End of period	$	832,143		$	672,341
	Weighted-average prepayment speed (CPR)		13	%		10.6	%
	Weighted-average discount rate		10	%		10	%
	The changes in fair value of MSRs that occurred during the three months ended March 31, 2015 and 2014 were mainly due to changes in principal balances and changes in estimate life of the MSRs.

Indemnification_Asset

Indemnification Asset	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Indemnification Asset	Note 11 – Indemnification Asset
	A summary of the activity in the balance of indemnification asset follows (in thousands):
		Three months ended March 31,
		2015			2014
	Beginning balance	$	(349	)	$	206
	Effect of actual and estimated future covered losses and recoveries		(62	)		(468	)
	Reimbursable (revenue) expenses incurred		(3	)		59
	Payments (received from) made to FDIC		(19	)		(17	)
	Ending balance	$	(433	)	$	(220	)
	Amount of indemnification asset (liability) recorded in other assets	$	114		$	(220	)
	Amount of indemnification asset (liability) recorded in other liabilities	$	(547	)		—
	Ending balance	$	(433	)	$	(220	)

Other_Assets

Other Assets	3 Months Ended
	Mar. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	Note 12 – Other Assets
	Other assets were comprised of (in thousands):
		March 31,		December 31,
		2015		2014
	Deferred tax asset, net	$	36,994	$	37,706
	Prepaid expense		3,268		2,034
	Software		1,198		1,327
	Advanced compensation		825		908
	Capital Trusts		1,691		1,690
	Miscellaneous other assets		7,026		8,070
	Total other assets	$	51,002	$	51,735

Deposits

Deposits	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
Deposits	Note 13 – Deposits
	A summary of the balances of deposits follows (in thousands):
		March 31		December 31,
		2015		2014
	Noninterest-bearing demand	$	1,034,012	$	1,083,900
	Interest-bearing demand		795,471		782,385
	Savings		1,172,257		1,156,126
	Time certificates, $250,000 and over		37,181		38,217
	Other time certificates		310,567		319,795
	Total deposits	$	3,349,488	$	3,380,423
	Certificate of deposit balances of $5,000,000 and $5,000,000 from the State of California were included in time certificates, $250,000 and over, at each of March 31, 2015 and December 31, 2014, respectively. The Bank participates in a deposit program offered by the State of California whereby the State may make deposits at the Bank’s request subject to collateral and credit worthiness constraints. The negotiated rates on these State deposits are generally more favorable than other wholesale funding sources available to the Bank. Overdrawn deposit balances of $1,096,000 and $1,216,000 were classified as consumer loans at March 31, 2015 and December 31, 2014, respectively.

Reserve_for_Unfunded_Commitmen

Reserve for Unfunded Commitments	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Reserve for Unfunded Commitments	Note 14 – Reserve for Unfunded Commitments
	The following tables summarize the activity in reserve for unfunded commitments for the periods indicated (dollars in thousands):
		Three months ended March 31,
		2015			2014
	Balance at beginning of period	$	2,145		$	2,415
	Provision for losses – Unfunded commitments		(130	)		(185	)
	Balance at end of period	$	2,015		$	2,230

Other_Liabilities

Other Liabilities	3 Months Ended
	Mar. 31, 2015
Other Liabilities Disclosure [Abstract]
Other Liabilities	Note 15 – Other Liabilities
	Other liabilities were comprised of (in thousands):
		March 31,		December 31,
		2015		2014
	Deferred compensation	$	7,484	$	7,408
	Pension liability		27,074		26,798
	Joint beneficiary agreements		2,785		2,728
	Miscellaneous other liabilities		15,913		12,258
	Total other liabilities	$	53,256	$	49,192

Other_Borrowings

Other Borrowings	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Other Borrowings	Note 16 – Other Borrowings
	A summary of the balances of other borrowings follows:
		March 31,		December 31,
		2015		2014
		(in thousands)
	Other collateralized borrowings, fixed rate, as of March 31, 2015 of 0.05%, payable on April 1, 2015	$	9,096	$	9,276
	Total other borrowings	$	9,096	$	9,276
	The Company did not enter into any repurchase agreements during the three months ended March 31, 2015 or the year ended December 31, 2014.
	The Company had $9,096,000 and $9,276,000 of other collateralized borrowings at March 31, 2015 and December 31, 2014, respectively. Other collateralized borrowings are generally overnight maturity borrowings from non-financial institutions that are collateralized by securities owned by the Company. As of March 31, 2015, the Company has pledged as collateral and sold under agreements to repurchase investment securities with fair value of $9,096,000 under these other collateralized borrowings.
	The Company maintains a collateralized line of credit with the Federal Home Loan Bank of San Francisco. Based on the FHLB stock requirements at March 31, 2015, this line provided for maximum borrowings of $978,743,000 of which none was outstanding, leaving $978,743,000 available. As of March 31, 2015, the Company has designated loans totaling $1,567,140,000 as potential collateral under this collateralized line of credit with the FHLB.
	The Company maintains a collateralized line of credit with the San Francisco Federal Reserve Bank. As of March 31, 2015, this line provided for maximum borrowings of $138,447,000 of which none was outstanding, leaving $138,447,000 available. As of March 31, 2015, the Company has designated investment securities with fair value of $427,000 and loans totaling $205,883,000 as potential collateral under this collateralized line of credit with the San Francisco Federal Reserve Bank.
	The Company has available unused correspondent banking lines of credit from commercial banks totaling $15,000,000 for federal funds transactions at March 31, 2015.

Junior_Subordinated_Debt

Junior Subordinated Debt	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Junior Subordinated Debt	Note 17 – Junior Subordinated Debt
	On July 31, 2003, the Company formed a subsidiary business trust, TriCo Capital Trust I, to issue trust preferred securities. Concurrently with the issuance of the trust preferred securities, the trust issued 619 shares of common stock to the Company for $1,000 per share or an aggregate of $619,000. In addition, the Company issued a junior subordinated debenture to the trust in the amount of $20,619,000. The terms of the junior subordinated debenture are materially consistent with the terms of the trust preferred securities issued by TriCo Capital Trust I. Also on July 31, 2003, TriCo Capital Trust I completed an offering of 20,000 shares of cumulative trust preferred securities for cash in an aggregate amount of $20,000,000. The trust preferred securities are mandatorily redeemable upon maturity on October 7, 2033 with an interest rate that resets quarterly at three-month LIBOR plus 3.05%. TriCo Capital Trust I has the right to redeem the trust preferred securities on or after October 7, 2008. The trust preferred securities were issued through an underwriting syndicate to which the Company paid underwriting fees of $7.50 per trust preferred security or an aggregate of $150,000. The net proceeds of $19,850,000 were used to finance the opening of new branches, improve bank services and technology, repurchase shares of the Company’s common stock under its repurchase plan and increase the Company’s capital.
	On June 22, 2004, the Company formed a second subsidiary business trust, TriCo Capital Trust II, to issue trust preferred securities. Concurrently with the issuance of the trust preferred securities, the trust issued 619 shares of common stock to the Company for $1,000 per share or an aggregate of $619,000. In addition, the Company issued a junior subordinated debenture to the trust in the amount of $20,619,000. The terms of the junior subordinated debenture are materially consistent with the terms of the trust preferred securities issued by TriCo Capital Trust II. Also on June 22, 2004, TriCo Capital Trust II completed an offering of 20,000 shares of cumulative trust preferred securities for cash in an aggregate amount of $20,000,000. The trust preferred securities are mandatorily redeemable upon maturity on July 23, 2034 with an interest rate that resets quarterly at three-month LIBOR plus 2.55%. TriCo Capital Trust II has the right to redeem the trust preferred securities on or after July 23, 2009. The trust preferred securities were issued through an underwriting syndicate to which the Company paid underwriting fees of $2.50 per trust preferred security or an aggregate of $50,000. The net proceeds of $19,950,000 were used to finance the opening of new branches, improve bank services and technology, repurchase shares of the Company’s common stock under its repurchase plan and increase the Company’s capital.
	As a result of the Company’s acquisition of North Valley Bancorp on October 3, 2014, the Company assumed the junior subordinated debentures issued by North Valley Bancorp to North Valley Capital Trusts II, III & IV with face amounts of $6,186,000, $5,155,000 and $10,310,000, respectively. Also, as a result of the North Valley Bancorp acquisition, the Company acquired common stock interests in North Valley Capital Trusts II, III and IV with face valley of $186,000, $155,000, and $310,000, respectively. At the acquisition date of October 3, 2014, the junior subordinated debentures associated with North Valley Capital Trust II, III and IV were recorded on the Company’s books at their fair values of $5,006,000, $3,918,000, and $6,063,000, respectively. The related fair value discounts to face value of these debentures will be amortized over the remaining time to maturity for each of these debentures using the effective interest method. Similar, and proportional, discounts were applied to the acquired common stock interest in North Valley Capital Trusts II, III and IV, and these discounts will be proportionally amortized over the remaining time to maturity for each related debenture.
	TriCo Capital Trusts I and II, and North Valley Capital Trusts II, III and IV are collectively referred to as the Capital Trusts. The recorded book values of the junior subordinated debentures issued by the Capital Trusts are reflected as junior subordinated debt in the Company’s consolidated balance sheets. The common stock issued by the Capital Trusts and owned by the Company is recorded in other assets in the Company’s consolidated balance sheets. The recorded book value of the debentures issued by the Capital Trusts, less the recorded book value of the common stock of the Capital Trusts owned by the Company, continues to qualify as Tier 1 or Tier 2 capital under interim guidance issued by the Board of Governors of the Federal Reserve System.
	The following table summarizes the terms and recorded balance of each subordinated debenture as of the date indicated (dollars in thousands):
						Coupon Rate			As of March 31, 2015
						(Variable)
	Subordinated Debt Series	Maturity		Face		3 mo. LIBOR +			Current			Recorded
		Date		Value					Coupon Rate			Book Value
	TriCo Cap Trust I		10/7/33	$	20,619		3.05	%		3.3	%	$	20,619
	TriCo Cap Trust II		7/23/34		20,619		2.55	%		2.81	%		20,619
	North Valley Trust II		4/24/33		6,186		3.25	%		3.5	%		5,025
	North Valley Trust III		4/24/34		5,155		2.8	%		3.06	%		3,936
	North Valley Trust IV		3/15/36		10,310		1.33	%		1.6	%		6,121
				$	62,889							$	56,320

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 18 – Commitments and Contingencies
	Restricted Cash Balances— Reserves (in the form of deposits with the San Francisco Federal Reserve Bank) of $64,997,000 and $57,616,000 were maintained to satisfy Federal regulatory requirements at March 31, 2015 and December 31, 2014. These reserves are included in cash and due from banks in the accompanying consolidated balance sheets.
	Lease Commitments— The Company leases 47 sites under non-cancelable operating leases. The leases contain various provisions for increases in rental rates, based either on changes in the published Consumer Price Index or a predetermined escalation schedule. Substantially all of the leases provide the Company with the option to extend the lease term one or more times following expiration of the initial term. The Company currently does not have any capital leases.
	At December 31, 2014, future minimum commitments under non-cancelable operating leases with initial or remaining terms of one year or more are as follows:
		Operating
		Leases
		(in thousands)
	2015	$	3,419
	2016		2,510
	2017		1,856
	2018		1,323
	2019		859
	Thereafter		1,180
	Future minimum lease payments	$	11,147
	Rent expense under operating leases was $959,000 and $755,000 during the three months ended March 31, 2015 and 2014, respectively. Rent expense was offset by rent income of $48,000 and $54,000 during the three months ended March 31, 2015 and 2014, respectively.
	Financial Instruments with Off-Balance-Sheet Risk— The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit, standby letters of credit, and deposit account overdraft privilege. Those instruments involve, to varying degrees, elements of risk in excess of the amount recognized in the balance sheet. The contract amounts of those instruments reflect the extent of involvement the Company has in particular classes of financial instruments.
	The Company’s exposure to loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and standby letters of credit written is represented by the contractual amount of those instruments. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. The Company’s exposure to loss in the event of nonperformance by the other party to the financial instrument for deposit account overdraft privilege is represented by the overdraft privilege amount disclosed to the deposit account holder.
	The following table presents a summary of the Bank’s commitments and contingent liabilities:
	(in thousands)	March 31,		December 31,
		2015		2014
	Financial instruments whose amounts represent risk:
	Commitments to extend credit:
	Commercial loans	$	195,295	$	177,557
	Consumer loans		392,005		392,705
	Real estate mortgage loans		40,014		36,139
	Real estate construction loans		40,935		49,774
	Standby letters of credit		16,307		17,531
	Deposit account overdraft privilege	$	99,002	$	101,060
	Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates of one year or less or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Company evaluates each customer’s credit worthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Company upon extension of credit, is based on Management’s credit evaluation of the customer. Collateral held varies, but may include accounts receivable, inventory, property, plant and equipment, residential properties, and income-producing commercial properties.
	Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support private borrowing arrangements. Most standby letters of credit are issued for one year or less. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. Collateral requirements vary, but in general follow the requirements for other loan facilities.
	Deposit account overdraft privilege amount represents the unused overdraft privilege balance available to the Company’s deposit account holders who have deposit accounts covered by an overdraft privilege. The Company has established an overdraft privilege for certain of its deposit account products whereby all holders of such accounts who bring their accounts to a positive balance at least once every thirty days receive the overdraft privilege. The overdraft privilege allows depositors to overdraft their deposit account up to a predetermined level. The predetermined overdraft limit is set by the Company based on account type.
	Legal Proceedings— The Bank owns 13,396 shares of Class B common stock of Visa Inc. which are convertible into Class A common stock at a conversion ratio of 1.648265 per Class B share. As of March 31, 2015, the value of the Class A shares was $65.41 per share. Utilizing the conversion ratio, the value of unredeemed Class A equivalent shares owned by the Bank was $1,444,000 as of March 31, 2015, and has not been reflected in the accompanying financial statements. The shares of Visa Class B common stock are restricted and may not be transferred. Visa Member Banks are required to fund an escrow account to cover settlements, resolution of pending litigation and related claims. If the funds in the escrow account are insufficient to settle all the covered litigation, Visa may sell additional Class A shares, use the proceeds to settle litigation, and further reduce the conversion ratio. If funds remain in the escrow account after all litigation is settled, the Class B conversion ratio will be increased to reflect that surplus.
	On January 24, 2014, a putative shareholder class action lawsuit was filed against TriCo, North Valley Bancorp and certain other defendants in connection with TriCo entering into the merger agreement with North Valley Bancorp. The lawsuit, which was filed in the Shasta County, California Superior Court, alleges that the members of the North Valley Bancorp board of directors breached their fiduciary duties to North Valley Bancorp shareholders by approving the proposed merger for inadequate consideration; approving the transaction in order receive benefits not equally shared by other North Valley Bancorp shareholders; entering into the merger agreement containing preclusive deal protection devices; and failing to take steps to maximize the value to be paid to the North Valley Bancorp shareholders. The lawsuit alleges claims against TriCo for aiding and abetting these alleged breaches of fiduciary duties. The plaintiff seeks, among other things, declaratory and injunctive relief concerning the alleged breaches of fiduciary duties injunctive relief prohibiting consummation of the merger, rescission, attorneys’ of the merger agreement, fees and costs, and other and further relief. On July 31, 2014 the defendants entered into a memorandum of understanding with the plaintiffs regarding the settlement of this lawsuit. In connection with the settlement contemplated by the memorandum of understanding and in consideration for the full settlement and release of all claims, TriCo and North Valley Bancorp agreed to make certain additional disclosures related to the proposed merger, which are contained in a Current Report on Form 8-K filed by each of the companies. The memorandum of understanding contemplates that the parties will negotiate in good faith and use their reasonable best efforts to enter into a stipulation of settlement. The stipulation of settlement will be subject to customary conditions, including court approval following notice to North Valley Bancorp’s shareholders. In the event that the parties enter into a stipulation of settlement, a hearing will be scheduled at which the court will consider the settlement. There can be no assurance that the parties will ultimately enter into a stipulation of settlement or that the court will approve the settlement even if the parties were to enter into such stipulation. In such event, the proposed settlement as contemplated by the memorandum of understanding may be terminated.
	On September 15, 2014, a former Personal Banker at one of the Bank’s in-store branches filed a Class Action Complaint against the Bank in Butte County Superior Court, alleging causes of action related to the observance of meal periods. Plaintiff seeks to represent a class of “current and former hourly-paid or non-exempt ‘personal bankers’, or employees with the same or similar job duties, employed by Defendants within the State of California during the preceding four years.” The Bank filed an Answer to the Complaint on November 6, 2014, denies the charges, and the Bank intends to vigorously defend the lawsuit against class certification and liability.
	On January 20, 2015, a current Personal Banker at one of the Bank’s in-store branches filed a First Amended Complaint against Tri Counties Bank and TriCo Bancshares, dba Tri Counties Bank, in Sacramento County Superior Court, alleging causes of action related to wage statement violations. Plaintiff seeks to represent a class of current and former exempt and non-exempt employees who worked for the Bank “during the time period beginning October 18, 2013 through the date of the filing of this action”. The Company and the Bank have not yet responded to the First Amended Complaint, deny the charges, and intend to vigorously defend the lawsuit against class certification and liability.
	Neither the Company nor its subsidiaries, are party to any other material pending legal proceeding, nor is their property the subject of any material pending legal proceeding, except routine legal proceedings arising in the ordinary course of their business. None of these proceedings is expected to have a material adverse impact upon the Company’s business, consolidated financial position or results of operations.
	Other Commitments and Contingencies—The Company has entered into employment agreements or change of control agreements with certain officers of the Company providing severance payments and accelerated vesting of benefits under supplemental retirement agreements to the officers in the event of a change in control of the Company and termination for other than cause or after a substantial and material change in the officer’s title, compensation or responsibilities.
	Mortgage loans sold to investors may be sold with servicing rights retained, with only the standard legal representations and warranties regarding recourse to the Bank. Management believes that any liabilities that may result from such recourse provisions are not significant.

Shareholders_Equity

Shareholders' Equity	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Shareholders' Equity	Note 19 – Shareholders’ Equity
	Dividends Paid
	The Bank paid to the Company cash dividends in the aggregate amounts of $2,120,000 and $2,050,000 during the three months ended March 31, 2015 and 2014 respectively. The Bank is regulated by the Federal Deposit Insurance Corporation (FDIC) and the State of California Department of Business Oversight. Absent approval from the Commissioner of the Department of Business Oversight, California banking laws generally limit the Bank’s ability to pay dividends to the lesser of (1) retained earnings or (2) net income for the last three fiscal years, less cash distributions paid during such period. Under this law, at December 31, 2014, the Bank may pay dividends of $52,798,000.
	Shareholders’ Rights Plan
	On June 25, 2001, the Company announced that its Board of Directors adopted and entered into a Shareholder Rights Agreement designed to protect and maximize shareholder value and to assist the Board of Directors in ensuring fair and equitable benefit to all shareholders in the event of a hostile bid to acquire the Company. The Company adopted this Rights Agreement to protect shareholders from coercive or otherwise unfair takeover tactics. In general terms, the Rights Plan would have imposed a significant penalty upon any person or group that acquired 15% or more of the Company’s outstanding common stock without approval of the Company’s Board of Directors.
	On June 4, 2014, the Company entered into an amendment to its Rights Agreement that accelerated the expiration of the Rights from July 10, 2021 to July 1, 2014 and had the effect of terminating the Rights Agreement as of that date. At the time of the termination, all Rights distributed to holders of the Company’s common stock pursuant to the Rights Agreement expired.
	Stock Repurchase Plan
	On August 21, 2007, the Board of Directors adopted a plan to repurchase, as conditions warrant, up to 500,000 shares of the Company’s common stock on the open market. The timing of purchases and the exact number of shares to be purchased will depend on market conditions. The 500,000 shares authorized for repurchase under this stock repurchase plan represented approximately 3.2% of the Company’s 15,814,662 outstanding common shares as of August 21, 2007. This stock repurchase plan has no expiration date. As of March 31, 2015, the Company had repurchased 166,600 shares under this plan.
	Stock Repurchased Under Equity Compensation Plans
	During the three months ended March 31, 2015 and 2014, employees tendered 21,461 and 100,385 shares, respectively, of the Company’s common stock with market value of $509,000, and $2,482,000, respectively, in lieu of cash to exercise options to purchase shares of the Company’s stock and to pay income taxes related to such exercises as permitted by the Company’s shareholder-approved equity compensation plans. The tendered shares were retired. The market value of tendered shares is the last market trade price at closing on the day an option is exercised. Stock repurchased under equity incentive plans are not included in the total of stock repurchased under the stock repurchase plan announced on August 21, 2007.

Stock_Options_and_Other_Equity

Stock Options and Other Equity-Based Incentive Instruments	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Options and Other Equity-Based Incentive Instruments	Note 20 – Stock Options and Other Equity-Based Incentive Instruments
	In March 2009, the Company’s Board of Directors adopted the TriCo Bancshares 2009 Equity Incentive Plan (2009 Plan) covering officers, employees, directors of, and consultants to, the Company. The 2009 Plan was approved by the Company’s shareholders in May 2009. The 2009 Plan allows for the granting of the following types of “stock awards” (Awards): incentive stock options, nonstatutory stock options, performance awards, restricted stock, restricted stock unit (RSU) awards and stock appreciation rights. RSUs that vest based solely on the grantee remaining in the service of the Company for a certain amount of time, are referred to as “service condition vesting RSUs”. RSUs that vest based on the grantee remaining in the service of the Company for a certain amount of time and a market condition such as the total return of the Company’s common stock versus the total return of an index of bank stocks, are referred to as “market plus service condition vesting RSUs”. In May 2013, the Company’s shareholders approved an amendment to the 2009 Plan increasing the maximum aggregate number of shares of TriCo’s common stock which may be issued pursuant to or subject to Awards from 650,000 to 1,650,000. The number of shares available for issuance under the 2009 Plan is reduced by: (i) one share for each share of common stock issued pursuant to a stock option or a Stock Appreciation Right and (ii) two shares for each share of common stock issued pursuant to a Performance Award, a Restricted Stock Award or a Restricted Stock Unit Award. When Awards made under the 2009 Plan expire or are forfeited or cancelled, the underlying shares will become available for future Awards under the 2009 Plan. To the extent that a share of common stock pursuant to an Award that counted as two shares against the number of shares again becomes available for issuance under the 2009 Plan, the number of shares of common stock available for issuance under the 2009 Plan shall increase by two shares. Shares awarded and delivered under the 2009 Plan may be authorized but unissued, or reacquired shares. As of March 31, 2015, 694,000 options for the purchase of common shares, and 46,427 restricted stock units were outstanding, and 822,146 shares remain available for issuance, under the 2009 Plan.
	In May 2001, the Company adopted the TriCo Bancshares 2001 Stock Option Plan (2001 Plan) covering officers, employees, directors of, and consultants to, the Company. Under the 2001 Plan, the option exercise price cannot be less than the fair market value of the Common Stock at the date of grant except in the case of substitute options. Options for the 2001 Plan expire on the tenth anniversary of the grant date. Vesting schedules under the 2001 Plan are determined individually for each grant. As of March 31, 2015, 361,850 options for the purchase of common shares were outstanding under the 2001 Plan. As of May 2009, as a result of the shareholder approval of the 2009 Plan, no new options may be granted under the 2001 Plan.
	Stock option activity during the three months ended March 31, 2015 is summarized in the following table:
		Number				Option Price							Weighted		Weighted
		of Shares				per Share							Average		Average Fair
													Exercise		Value on
													Price		Date of Grant
	Outstanding at December 31, 2014		1,102,850			$	12.63			to	$	25.91	$	18.25
	Options granted		—				—			to		—		—		—
	Options exercised		(47,000	)		$	15.34			to	$	19.46	$	18.86
	Options forfeited		—				—			to		—		—
	Outstanding at March 31, 2015		1,055,850			$	12.63			to	$	25.91	$	18.22
	The following table shows the number, weighted-average exercise price, intrinsic value, and weighted average remaining contractual life of options exercisable, options not yet exercisable and total options outstanding as of March 31, 2015:
		Currently				Currently Not			Total
		Exercisable				Exercisable			Outstanding
	Number of options		772,850				283,000			1,055,850
	Weighted average exercise price	$	18.6			$	17.2		$	18.22
	Intrinsic value (in thousands)	$	4,334			$	1,962		$	6,296
	Weighted average remaining contractual term (yrs.)		4.4				7.3			5.2
	The 283,000 options that are currently not exercisable as of March 31, 2015 are expected to vest, on a weighted-average basis, over the next 2.3 years, and the Company is expected to recognize $1,562,000 of pre-tax compensation costs related to these options as they vest. The Company did not modify any option grants during 2014 or the three months ended March 31, 2015.
	Restricted stock unit (RSU) activity is summarized in the following table for the dates indicated:
		Service Condition Vesting RSUs						Market Plus Service Condition Vesting RSUs
		Number		Weighted				Number	Weighted
		of RSUs		Average Fair				of RSUs	Average Fair
				Value on					Value on
				Date of Grant					Date of Grant
	Outstanding at December 31, 2014	30,920						15,366
	RSUs granted	—			—			—		—
	RSUs added through dividend credits	141						—
	RSUs released	—						—
	RSUs forfeited/expired	—						—
	Outstanding at March 31, 2015	31,061						15,366
	The 31,061 of service condition vesting RSUs outstanding as of March 31, 2015 include a feature whereby each RSU outstanding is credited with a dividend amount equal to any common stock cash dividend declared and paid, and the credited amount is divided by the closing price of the Company’s stock on the dividend payable date to arrive at an additional amount of RSUs outstanding under the original grant. The 31,061 of service condition vesting RSUs outstanding as of March 31, 2015 are expected to vest, and be released, on a weighted-average basis, over the next 2.6 years. The Company is expected to recognize $489,000 of pre-tax compensation costs related to these service condition vesting RSUs between March 31, 2015 and their vesting dates. During the three months ended March 31, 2015, the Company did not modify any service condition vesting RSUs. During the three months ended December 31, 2014, the Company modified 13,749 service condition vesting RSUs that were granted on August 11, 2014 such that their vesting schedule was changed from 100% vesting on August 11, 2018 to 25% vesting on each of August 11, 2015, 2016, 2017 and 2018. During the nine months ended September 30, 2014, the Company did not modify any service condition vesting RSUs.
	The 15,366 of market plus service condition vesting RSUs that are currently outstanding as of March 31, 2015 are expected to vest, and be released, on a weighted-average basis, over the next 2.4 years. The Company is expected to recognize $259,000 of pre-tax compensation costs related to these RSUs between March 31, 2015 and their vesting dates. As of March 31, 2015, the number of market plus service condition vesting RSUs outstanding that will actually vest, and be released, may be reduced to zero or increased to 23,049 depending on the total return of the Company’s common stock versus the total return of an index of bank stocks from the grant date to the vesting date. The Company did not modify any market plus service condition vesting RSUs during the three months ended March 31, 2015 or during the year ended December 31, 2014.

Noninterest_Income_and_Expense

Noninterest Income and Expense	3 Months Ended
	Mar. 31, 2015
Other Income and Expenses [Abstract]
Noninterest Income and Expense	Note 21 – Noninterest Income and Expense
	The components of other noninterest income were as follows (in thousands):
		Three months ended March 31,
		2015			2014
	Service charges on deposit accounts	$	3,600		$	2,690
	ATM and interchange fees		3,002			2,013
	Other service fees		714			520
	Mortgage banking service fees		534			420
	Change in value of mortgage servicing rights		(506	)		(181	)
	Total service charges and fees		7,344			5,462
	Gain on sale of loans		622			464
	Commissions on sale of non-deposit investment products		965			771
	Increase in cash value of life insurance		675			397
	Change in indemnification asset		(65	)		(412	)
	Gain on sale of foreclosed assets		311			1,227
	Sale of customer checks		128			101
	Lease brokerage income		137			107
	Loss on disposal of fixed assets		(84	)		(1	)
	Other		147			179
	Total other noninterest income		2,836			2,833
	Total noninterest income	$	10,180		$	8,295
	Mortgage loan servicing fees, net of change in fair value of mortgage loan servicing rights, totaling $28,000 and $239,000 were recorded in service charges and fees noninterest income for the three months ended March 31, 2015 and 2014, respectively.
	The components of noninterest expense were as follows (in thousands):
		Three months ended March 31,
		2015			2014
	Base salaries, net of deferred loan origination costs	$	11,744		$	8,866
	Incentive compensation		1,596			1,123
	Benefits and other compensation costs		4,760			3,314
	Total salaries and benefits expense		18,100			13,303
	Occupancy		2,417			1,962
	Equipment		1,414			1,036
	Data processing and software		1,952			1,178
	ATM network charges		770			643
	Telecommunications		886			580
	Postage		312			227
	Courier service		248			234
	Advertising		808			342
	Assessments		651			521
	Operational losses		124			177
	Professional fees		1,119			614
	Foreclosed assets expense		98			158
	Provision for foreclosed asset losses		67			36
	Change in reserve for unfunded commitments		(130	)		(185	)
	Intangible amortization		289			52
	Merger expense		586			225
	Other		2,571			2,214
	Total other noninterest expense		14,182			10,014
	Total noninterest expense	$	32,282		$	23,317
	Merger expense:
	Data processing and software	$	108			—
	Professional fees		120		$	225
	Other		358			—
	Total merger expense	$	586		$	225

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Note 22 – Income Taxes
	The provisions for income taxes applicable to income before taxes differ from amounts computed by applying the statutory Federal income tax rates to income before taxes. The effective tax rate and the statutory federal income tax rate are reconciled for the periods indicated as follows:
		Three months ended March 31,
		2015			2014
	Federal statutory income tax rate		35	%		35	%
	State income taxes, net of federal tax benefit		6.9			6.9
	Tax-exempt interest on municipal obligations		(0.4	)		(0.4	)
	Increase in cash value of insurance policies		(1.7	)		(1.1	)
	Other		0.8			0.2
	Effective Tax Rate		40.6	%		40.6	%

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Earnings Per Share	Note 23 – Earnings Per Share
	Basic earnings per share represents income available to common shareholders divided by the weighted-average number of common shares outstanding during the period. Diluted earnings per share reflects additional common shares that would have been outstanding if dilutive potential common shares had been issued, as well as any adjustments to income that would result from assumed issuance. Potential common shares that may be issued by the Company relate solely from outstanding stock options, and are determined using the treasury stock method. Earnings per share have been computed based on the following:
		Three months ended
		March 31,
	(In thousands)	2015		2014
	Net income	$	8,336	$	7,365
	Average number of common shares outstanding		22,727		16,097
	Effect of dilutive stock options and restricted stock		223		225
	Average number of common shares outstanding used to calculate diluted earnings per share		22,950		16,322
	Options excluded from diluted earnings per share because the effect of these options was antidilutive		23		101
	Restricted stock excluded from diluted earnings per share because the effect of these restricted stock was antidilutive		—		n/a

Comprehensive_Income

Comprehensive Income	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Comprehensive Income	Note 24 – Comprehensive Income
	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Although certain changes in assets and liabilities, such as unrealized gains and losses on available-for-sale securities, are reported as a separate component of the equity section of the balance sheet, such items, along with net income, are components of comprehensive income. The components of other comprehensive income and related tax effects are as follows:
		Three Months Ended
		March 31,
		2015			2014
	(in thousands)
	Unrealized holding gains (losses) on available for sale securities before reclassifications	$	15		$	(105	)
	Amounts reclassified out of accumulated other comprehensive income-		—			—
	Unrealized holding gains (losses) on available for sale securities after reclassifications		15			(105	)
	Tax effect		(6	)		45
	Unrealized holding gains (losses) on available for sale securities, net of tax		9			(60	)
	Change in unfunded status of the supplemental retirement plans before reclassifications		—			—
	Amounts reclassified out of accumulated other comprehensive income:
	Amortization of prior service cost		(14	)		5
	Amortization of actuarial losses		206			4
	Total amounts reclassified out of accumulated other comprehensive income		192			9
	Change in unfunded status of the supplemental retirement plans after reclassifications		192			9
	Tax effect		(81	)		(4	)
	Change in unfunded status of the supplemental retirement plans, net of tax		111			5
	Change in joint beneficiary agreement liability before reclassifications		—			—
	Amounts reclassified out of accumulated other comprehensive income		—			—
	Change in joint beneficiary agreement liability after reclassifications		—			—
	Tax effect		—			—
	Change in joint beneficiary agreement liability, net of tax		—			—
	Total other comprehensive gain (loss)	$	120		$	(55	)
	The components of accumulated other comprehensive income, included in shareholders’ equity, are as follows:
		March 31,			December 31,
		2015			2014
		(in thousands)
	Net unrealized gains on available for sale securities	$	4,055		$	4,040
	Tax effect		(1,705	)		(1,699	)
	Unrealized holding gains on available for sale securities, net of tax		2,350			2,341
	Unfunded status of the supplemental retirement plans		(7,693	)		(7,885	)
	Tax effect		3,234			3,315
	Unfunded status of the supplemental retirement plans, net of tax		(4,459	)		(4,570	)
	Joint beneficiary agreement liability		26			26
	Tax effect		—			—
	Joint beneficiary agreement liability, net of tax		26			26
	Accumulated other comprehensive loss	$	(2,083	)	$	(2,203	)

Retirement_Plans

Retirement Plans	3 Months Ended
	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Retirement Plans	Note 25 – Retirement Plans
	401(k) Plan
	The Company sponsors a 401(k) Plan whereby substantially all employees age 21 and over with 90 days of service may participate. Participants may contribute a portion of their compensation subject to certain limits based on federal tax laws. The Company does not contribute to the 401(k) Plan. The Company did not incur any material expenses attributable to the 401(k) Plan during 2014 or the three months ended March 31, 2015.
	Employee Stock Ownership Plan
	Substantially all employees with at least one year of service are covered by a discretionary employee stock ownership plan (ESOP). Contributions are made to the plan at the discretion of the Board of Directors. Contributions to the plan totaling $368,000 and $195,000 during the three months ended March 31, 2015 and 2014, respectively, are included in salary expense. Company shares owned by the ESOP are paid dividends and included in the calculation of earnings per share exactly as other common shares outstanding.
	Deferred Compensation Plans
	The Company has deferred compensation plans for certain directors and key executives, which allow certain directors and key executives designated by the Board of Directors of the Company to defer a portion of their compensation. The Company has purchased insurance on the lives of the participants and intends to hold these policies until death as a cost recovery of the Company’s deferred compensation obligations of $7,484,000 and $7,408,000 at March 31, 2015 and December 31, 2014, respectively. Earnings credits on deferred balances totaling $149,000 and $152,000 during the three months ended March 31, 2015 and 2014, respectively, are included in noninterest expense.
	Supplemental Retirement Plans
	The Company has supplemental retirement plans for current and former directors and key executives. These plans are non-qualified defined benefit plans and are unsecured and unfunded. The Company has purchased insurance on the lives of the participants and intends (but is not required) to use the cash values of these policies to pay the retirement obligations. The following table sets forth the net periodic benefit cost recognized for the plans:
		Three months ended March 31,
		2015			2014
		(In thousands)
	Net pension cost included the following components:
	Service cost-benefits earned during the period	$	256		$	163
	Interest cost on projected benefit obligation		239			174
	Amortization of net obligation at transition		—			—
	Amortization of prior service cost		(14	)		35
	Recognized net actuarial loss		206			4
	Net periodic pension cost	$	687		$	376
	During the three months ended March 31, 2015 and 2014, the Company contributed and paid out as benefits $219,000 and $125,000, respectively, to participants under the plans. For the year ending December 31, 2015, the Company expects to contribute and pay out as benefits $1,194,000 to participants under the plans.

Related_Party_Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	Note 26 – Related Party Transactions
	Certain directors, officers, and companies with which they are associated were customers of, and had banking transactions with, the Company or the Bank in the ordinary course of business.
	The following table summarizes the activity in these loans for 2015 and 2014 (in thousands):
	Balance December 31, 2013	$	2,636
	Advances/new loans		2,106
	Removed/payments		(1,610	)
	Balance December 31, 2014	$	3,132
	Advances/new loans		235
	Removed/payments		(416	)
	Balance March 31, 2015	$	2,951
	Director Chrysler is a principal owner and CEO of Modern Building Inc. Modern Building Inc. provided construction services to the Company related to new and existing Bank facilities for aggregate payments of $166,000 during the three months ended March 31, 2015 and $1,181,000 during the year ended December 31, 2014.

Fair_Value_Measurement

Fair Value Measurement	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurement	Note 27 – Fair Value Measurement
	The Company utilizes fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. In estimating fair value, the Company utilizes valuation techniques that are consistent with the market approach, income approach, and/or the cost approach. Inputs to valuation techniques include the assumptions that market participants would use in pricing an asset or liability including assumptions about the risk inherent in a particular valuation technique, the effect of a restriction on the sale or use of an asset and the risk of nonperformance. Securities available-for-sale and mortgage servicing rights are recorded at fair value on a recurring basis. Additionally, from time to time, the Company may be required to record at fair value other assets on a nonrecurring basis, such as loans held for sale, loans held for investment and certain other assets. These nonrecurring fair value adjustments typically involve application of lower of cost or market accounting or impairment write-downs of individual assets.
	The Company groups assets and liabilities at fair value in three levels, based on the markets in which the assets and liabilities are traded and the observable nature of the assumptions used to determine fair value. These levels are:
	Level 1 -			Valuation is based upon quoted prices for identical instruments traded in active markets.
	Level 2 -			Valuation is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market.
	Level 3 -			Valuation is generated from model-based techniques that use at least one significant assumption not observable in the market. These unobservable assumptions reflect estimates of assumptions that market participants would use in pricing the asset or liability. Valuation techniques include use of option pricing models, discounted cash flow models and similar techniques.
	Securities available for sale – Securities available for sale are recorded at fair value on a recurring basis. Fair value measurement is based upon quoted prices, if available. If quoted prices are not available, fair values are measured using independent pricing models or other model-based valuation techniques such as the present value of future cash flows, adjusted for the security’s credit rating, prepayment assumptions and other factors such as credit loss assumptions. Level 1 securities include those traded on an active exchange, such as the New York Stock Exchange, U.S. Treasury securities that are traded by dealers or brokers in active over-the-counter markets and money market funds. Level 2 securities include mortgage-backed securities issued by government sponsored entities, municipal bonds and corporate debt securities. The Company had no securities classified as Level 3 during any of the periods covered in these financial statements.
	Loans held for sale – Loans held for sale are carried at the lower of cost or fair value. The fair value of loans held for sale is based on what secondary markets are currently offering for loans with similar characteristics. As such, we classify those loans subjected to nonrecurring fair value adjustments as Level 2.
	Impaired originated and PNCI loans – Originated and PNCI loans are not recorded at fair value on a recurring basis. However, from time to time, an originated or PNCI loan is considered impaired and an allowance for loan losses is established. Originated and PNCI loans for which it is probable that payment of interest and principal will not be made in accordance with the contractual terms of the loan agreement are considered impaired. The fair value of an impaired originated or PNCI loan is estimated using one of several methods, including collateral value, fair value of similar debt, enterprise value, liquidation value and discounted cash flows. Those impaired originated and PNCI loans not requiring an allowance represent loans for which the fair value of the expected repayments or collateral exceed the recorded investments in such loans. Impaired originated and PNCI loans where an allowance is established based on the fair value of collateral require classification in the fair value hierarchy. When the fair value of the collateral is based on an observable market price or a current appraised value which uses substantially observable data, the Company records the impaired originated or PNCI loan as nonrecurring Level 2. When an appraised value is not available or management determines the fair value of the collateral is further impaired below the appraised value, or the appraised value contains a significant unobservable assumption, such as deviations from comparable sales, and there is no observable market price, the Company records the impaired originated or PNCI loan as nonrecurring Level 3.
	Foreclosed assets – Foreclosed assets include assets acquired through, or in lieu of, loan foreclosure. Foreclosed assets are held for sale and are initially recorded at fair value at the date of foreclosure, establishing a new cost basis. Subsequent to foreclosure, management periodically performs valuations and the assets are carried at the lower of carrying amount or fair value less cost to sell. When the fair value of foreclosed assets is based on an observable market price or a current appraised value which uses substantially observable data, the Company records the impaired originated loan as nonrecurring Level 2. When an appraised value is not available or management determines the fair value of the collateral is further impaired below the appraised value, or the appraised value contains a significant unobservable assumption, such as deviations from comparable sales, and there is no observable market price, the Company records the foreclosed asset as nonrecurring Level 3. Revenue and expenses from operations and changes in the valuation allowance are included in other noninterest expense.
	Mortgage servicing rights – Mortgage servicing rights are carried at fair value. A valuation model, which utilizes a discounted cash flow analysis using a discount rate and prepayment speed assumptions is used in the computation of the fair value measurement. While the prepayment speed assumption is currently quoted for comparable instruments, the discount rate assumption currently requires a significant degree of management judgment and is therefore considered an unobservable input. As such, the Company classifies mortgage servicing rights subjected to recurring fair value adjustments as Level 3. Additional information regarding mortgage servicing rights can be found in Note 10 in the consolidated financial statements at Item 1 of this report.
	The table below presents the recorded amount of assets and liabilities measured at fair value on a recurring basis (in thousands):
		Total			Level 1			Level 2			Level 3
	Fair value at March 31, 2015
	Securities available for sale:
	Obligations of U.S. government corporations and agencies	$	210,535			—		$	210,535			—
	Obligations of states and political subdivisions		9,656			—			9,656			—
	Corporate debt securities		1,905			—			1,905			—
	Marketable equity services		3,030		$	3,030			—			—
	Mortgage servicing rights		7,057			—			—		$	7,057
	Total assets measured at fair value	$	232,183		$	3,030		$	222,096		$	7,057
		Total			Level 1			Level 2			Level 3
	Fair value at December 31, 2014
	Securities available for sale:
	Obligations of U.S. government corporations and agencies	$	75,120			—		$	75,120			—
	Obligations of states and political subdivisions		3,175			—			3,175			—
	Corporate debt securities		1,908			—			1,908			—
	Marketable equity securities		3,002		$	3,002			—			—
	Mortgage servicing rights		7,378			—			—		$	7,378
	Total assets measured at fair value	$	90,583		$	3,002		$	80,203		$	7,378
	Transfers between levels of the fair value hierarchy are recognized on the actual date of the event or circumstances that caused the transfer, which generally corresponds with the Company’s quarterly valuation process. There were no transfers between any levels during the three months ended March 31, 2015 or the year ended December 31, 2014.
	The following table provides a reconciliation of assets and liabilities measured at fair value using significant unobservable inputs (Level 3) on a recurring basis during the time periods indicated. Had there been any transfer into or out of Level 3 during the time periods indicated, the amount included in the “Transfers into (out of) Level 3” column would represent the beginning balance of an item in the period (interim quarter) during which it was transferred (in thousands):
		Beginning			Transfers			Change			Issuances			Ending
		Balance			into (out of)			Included						Balance
					Level 3			in Earnings
	Three months ended March 31,
	2015: Mortgage servicing rights	$	7,378			—		$	(506	)	$	185		$	7,057
	2014: Mortgage servicing rights	$	6,165			—		$	(181	)	$	123		$	6,107
	The Company’s method for determining the fair value of mortgage servicing rights is described in Note 1. The key unobservable inputs used in determining the fair value of mortgage servicing rights are mortgage prepayment speeds and the discount rate used to discount cash projected cash flows. Generally, any significant increases in the mortgage prepayment speed and discount rate utilized in the fair value measurement of the mortgage servicing rights will result in a negative fair value adjustments (and decrease in the fair value measurement). Conversely, a decrease in the mortgage prepayment speed and discount rate will result in a positive fair value adjustment (and increase in the fair value measurement). Note 10 contains additional information regarding mortgage servicing rights.
	The following table presents quantitative information about recurring Level 3 fair value measurements at March 31, 2015:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Mortgage Servicing Rights	$	7,057		Discounted cash flow		Constant prepayment rate	6.0%-23.1%, 13.0%
							Discount rate	10.0%-12.0%, 10.0%
	The following table presents quantitative information about recurring Level 3 fair value measurements at December 31, 2014:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Mortgage Servicing Rights	$	7,378		Discounted cash flow		Constant prepayment rate	5.7%-23.4%, 12.0%
							Discount rate	10.0%-12.0%, 10.0%
	The tables below present the recorded amount of assets and liabilities measured at fair value on a nonrecurring basis, as of the dates indicated, that had a write-down or an additional allowance provided during the periods indicated (in thousands):
		Total			Level 1			Level 2			Level 3			Total
														(Losses)
	Three months ended March 31, 2015
	Fair value:
	Impaired Originated & PNCI loans	$	3,690			—			—		$	3,690		$	(181	)
	Foreclosed assets		2,384			—			—			2,384			(64	)
	Total assets measured at fair value	$	6,074			—			—		$	6,074		$	(245	)
		Total			Level 1			Level 2			Level 3			Total
														(Losses)
	Year ended December 31, 2014
	Fair value:
	Impaired Originated & PNCI loans	$	2,480			—			—		$	2,480		$	(636	)
	Foreclosed assets		2,611			—			—			2,611			(137	)
	Total assets measured at fair value	$	5,091			—			—		$	5,091		$	(773	)
	Total			Level 1			Level 2			Level 3			Total
													(Losses)
Three months ended March 31, 2014
Fair value:
Impaired Originated & PNCI loans	$	21,498			—			—		$	21,498		$	(272	)
Foreclosed assets		802			—			—			802			(21	)
Total assets measured at fair value	$	22,300			—			—		$	22,300		$	(293	)
The impaired Originated and PNCI loan amount above represents impaired, collateral dependent loans that have been adjusted to fair value. When we identify a collateral dependent loan as impaired, we measure the impairment using the current fair value of the collateral, less selling costs. Depending on the characteristics of a loan, the fair value of collateral is generally estimated by obtaining external appraisals. If we determine that the value of the impaired loan is less than the recorded investment in the loan, we recognize this impairment and adjust the carrying value of the loan to fair value through the allowance for loan and lease losses. The loss represents charge-offs or impairments on collateral dependent loans for fair value adjustments based on the fair value of collateral. The carrying value of loans fully charged-off is zero.
The foreclosed assets amount above represents impaired real estate that has been adjusted to fair value. Foreclosed assets represent real estate which the Bank has taken control of in partial or full satisfaction of loans. At the time of foreclosure, other real estate owned is recorded at the lower of the carrying amount of the loan or fair value less costs to sell, which becomes the property’s new basis. Any write-downs based on the asset’s fair value at the date of acquisition are charged to the allowance for loan and lease losses. After foreclosure, management periodically performs valuations such that the real estate is carried at the lower of its new cost basis or fair value, net of estimated costs to sell. Fair value adjustments on other real estate owned are recognized within net loss on real estate owned. The loss represents impairments on non-covered other real estate owned for fair value adjustments based on the fair value of the real estate.
The Company’s property appraisals are primarily based on the sales comparison approach and income approach methodologies, which consider recent sales of comparable properties, including their income generating characteristics, and then make adjustments to reflect the general assumptions that a market participant would make when analyzing the property for purchase. These adjustments may increase or decrease an appraised value and can vary significantly depending on the location, physical characteristics and income producing potential of each property. Additionally, the quality and volume of market information available at the time of the appraisal can vary from period to period and cause significant changes to the nature and magnitude of comparable sale adjustments. Given these variations, comparable sale adjustments are generally not a reliable indicator for how fair value will increase or decrease from period to period. Under certain circumstances, management discounts are applied based on specific characteristics of an individual property.
The following table presents quantitative information about Level 3 fair value measurements for financial instruments measured at fair value on a nonrecurring basis at March 31, 2015:
	Fair Value			Valuation		Unobservable	Range,
	(in thousands)			Technique		Inputs	Weighted Average
Impaired Originated & PNCI loans	$	3,690		Sales comparison		Adjustment for differences	(5.0)%-(41.0)%, (8.8)%
				approach		between comparable sales	8.0%-9.1%, 8.1%
				Income approach		Capitalization rate
Foreclosed assets	$	2,384		Sales comparison		Adjustment for differences	(5.0)%-(30.1)%, (9.3)%
				approach		between comparable sales
The following table presents quantitative information about Level 3 fair value measurements for financial instruments measured at fair value on a nonrecurring basis at December 31, 2014:
	Fair Value			Valuation		Unobservable	Range,
	(in thousands)			Technique		Inputs	Weighted Average
Impaired Originated & PNCI loans	$	2,480		Sales comparison		Adjustment for differences	(5.0)%-(42.5)%, (10.1)%
				approach		between comparable sales	9.09%-9.09%, 9.09%
				Income approach		Capitalization rate
Foreclosed assets	$	2,611		Sales comparison		Adjustment for differences	(5.0)%-(29.4)%, (8.2)%
				approach		between comparable sales
In addition to the methods and assumptions used to estimate the fair value of each class of financial instrument noted above, the following methods and assumptions were used to estimate the fair value of other classes of financial instruments for which it is practical to estimate the fair value.
Short-term Instruments – Cash and due from banks, fed funds purchased and sold, interest receivable and payable, and short-term borrowings are considered short-term instruments. For these short-term instruments their carrying amount approximates their fair value.
Securities held to maturity – The fair value of securities held to maturity is based upon quoted prices, if available. If quoted prices are not available, fair values are measured using independent pricing models or other model-based valuation techniques such as the present value of future cash flows, adjusted for the security’s credit rating, prepayment assumptions and other factors such as credit loss assumptions. Level 1 securities include those traded on an active exchange, such as the New York Stock Exchange, U.S. Treasury securities that are traded by dealers or brokers in active over-the-counter markets and money market funds. Level 2 securities include mortgage-backed securities issued by government sponsored entities, municipal bonds and corporate debt securities. The Company had no securities held to maturity classified as Level 3 during any of the periods covered in these financial statements.
Restricted Equity Securities – The carrying value of restricted equity securities approximates fair value as the shares can only be redeemed by the issuing institution at par.
Originated and PNCI loans - The fair value of variable rate originated and PNCI loans is the current carrying value. The interest rates on these originated and PNCI loans are regularly adjusted to market rates. The fair value of other types of fixed rate originated and PNCI loans is estimated by discounting the future cash flows using current rates at which similar loans would be made to borrowers with similar credit ratings for the same remaining maturities. The allowance for loan losses is a reasonable estimate of the valuation allowance needed to adjust computed fair values for credit quality of certain originated and PNCI loans in the portfolio.
PCI Loans – PCI loans are measured at estimated fair value on the date of acquisition. Carrying value is calculated as the present value of expected cash flows and approximates fair value.
Deposit Liabilities – The fair value of demand deposits, savings accounts, and certain money market deposits is the amount payable on demand at the reporting date. These values do not consider the estimated fair value of the Company’s core deposit intangible, which is a significant unrecognized asset of the Company. The fair value of time deposits and other borrowings is based on the discounted value of contractual cash flows.
Other Borrowings – The fair value of other borrowings is calculated based on the discounted value of the contractual cash flows using current rates at which such borrowings can currently be obtained.
Junior Subordinated Debentures – The fair value of junior subordinated debentures is estimated using a discounted cash flow model. The future cash flows of these instruments are extended to the next available redemption date or maturity date as appropriate based upon the spreads of recent issuances or quotes from brokers for comparable bank holding companies compared to the contractual spread of each junior subordinated debenture measured at fair value.
Commitments to Extend Credit and Standby Letters of Credit – The fair value of commitments is estimated using the fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the present credit worthiness of the counter parties. For fixed rate loan commitments, fair value also considers the difference between current levels of interest rates and the committed rates. The fair value of letters of credit is based on fees currently charged for similar agreements or on the estimated cost to terminate them or otherwise settle the obligation with the counter parties at the reporting date.
Fair values for financial instruments are management’s estimates of the values at which the instruments could be exchanged in a transaction between willing parties. These estimates are subjective and may vary significantly from amounts that would be realized in actual transactions. In addition, other significant assets are not considered financial assets including, any mortgage banking operations, deferred tax assets, and premises and equipment. Further, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on the fair value estimates and have not been considered in any of these estimates.
The estimated fair values of financial instruments that are reported at amortized cost in the Corporation’s consolidated balance sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows (in thousands):
	March 31, 2015						December 31, 2014
	Carrying			Fair			Carrying			Fair
	Amount			Value			Amount			Value
Financial assets:
Level 1 inputs:
Cash and due from banks	$	84,682		$	84,682		$	93,150		$	93,150
Cash at Federal Reserve and other banks		196,546			196,546			517,578			517,578
Level 2 inputs:
Securities held to maturity		802,482			817,793			676,426			688,779
Restricted equity securities		16,956			N/A			16,956			N/A
Loans held for sale		5,413			5,413			3,579			3,579
Level 3 inputs:
Loans, net		2,284,828			2,379,343			2,245,938			2,342,570
Indemnification (liability) asset		(433	)		(433	)		(349	)		(349	)
Financial liabilities:
Level 2 inputs:
Deposits		3,349,488			3,349,507			3,380,423			3,380,486
Other borrowings		9,096			9,096			9,276			9,276
Level 3 inputs:
Junior subordinated debt		56,320			46,424			56,272			45,053
	Contract			Fair			Contract			Fair
	Amount			Value			Amount			Value
Off-balance sheet:
Level 3 inputs:
Commitments	$	668,249		$	6,682		$	656,175		$	6,562
Standby letters of credit		16,307			163			17,531			175
Overdraft privilege commitments		99,002			990			101,060			1,011

TriCo_Bancshares_Condensed_Fin

TriCo Bancshares Condensed Financial Statements (Parent Only)	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
TriCo Bancshares Condensed Financial Statements (Parent Only)	Note 28 – TriCo Bancshares Condensed Financial Statements (Parent Only)
	Condensed Balance Sheets
		March 31,			December 31,
		2015			2014
		(In thousands)
	Assets
	Cash and Cash equivalents	$	2,044		$	2,229
	Investment in Tri Counties Bank		477,845			470,797
	Other assets		1,738			1,902
	Total assets	$	481,627		$	474,928
	Liabilities and shareholders’ equity
	Other liabilities	$	474		$	484
	Junior subordinated debt		56,320			56,272
	Total liabilities		56,794			56,756
	Shareholders’ equity:
	Common stock, no par value: authorized 50,000,000 shares; issued and outstanding 22,740,503 and 22,714,964 shares, respectively		245,316			244,318
	Retained earnings		181,600			176,057
	Accumulated other comprehensive loss, net		(2,083	)		(2,203	)
	Total shareholders’ equity		424,833			418,172
	Total liabilities and shareholders’ equity	$	481,627		$	474,928
	Condensed Statements of Income
		Three months ended March 31,
		2015			2014
		(In thousands)
	Interest expense	$	482		$	304
	Administration expense		153			324
	Loss before equity in net income of Tri Counties Bank		(635	)		(628	)
	Equity in net income of Tri Counties Bank:
	Distributed		2,120			2,050
	Under distributed		6,584			5,679
	Income tax benefit		267			264
	Net income	$	8,336		$	7,365
	Condensed Statements of Comprehensive Income
		Three months ended March 31,
		2015			2014
		(In thousands)
	Net income	$	8,336		$	7,365
	Other comprehensive loss, net of tax:
	Increase (decrease) in unrealized gains on available for sale securities arising during the period		9			(60	)
	Change in minimum pension liability		111			5
	Other comprehensive loss		120			(55	)
	Comprehensive income	$	8,456		$	7,310
	Condensed Statements of Cash Flows
		Three months ended March 31,
		2015			2014
		(In thousands)
	Operating activities:
	Net income	$	8,336		$	7,365
	Adjustments to reconcile net income to net cash provided by operating activities:
	Under distributed equity in earnings of Tri Counties Bank		(6,584	)		(5,679	)
	Equity compensation vesting expense		324			296
	Stock option excess tax benefits		(18	)		(184	)
	Net change in other assets and liabilities		(124	)		(360	)
	Net cash provided by operating activities		1,934			1,438
	Investing activities: None
	Financing activities:
	Stock option excess tax benefits		18			184
	Issuance of common stock through option exercise		405			306
	Repurchase of common stock		(27	)		(293	)
	Cash dividends paid — common		(2,515	)		(1,772	)
	Net cash used for financing activities		(2,119	)		(1,575	)
	Net change in cash and cash equivalents		(185	)		(137	)
	Cash and cash equivalents at beginning of year		2,229			2,520
	Cash and cash equivalents at end of year	$	2,044		$	2,383

Regulatory_Matters

Regulatory Matters	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
Regulatory Matters	Note 29 – Regulatory Matters
	The Company is subject to various regulatory capital requirements administered by federal banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory, and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company must meet specific capital guidelines that involve quantitative measures of the Company’s assets, liabilities and certain off-balance-sheet items as calculated under regulatory accounting practices. The Company’s capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors.
	Quantitative measures established by regulation to ensure capital adequacy require the Company to maintain minimum amounts and ratios (set forth in the table below) of total, Tier 1, and common equity Tier 1capital to risk-weighted assets, and of Tier 1 capital to average assets. Management believes, as of March 31, 2015, that the Company meets all capital adequacy requirements to which it is subject.
	The following table presents actual and required capital ratios as of March 31, 2015 for the Company and the Bank under Basel III Capital Rules. The minimum capital amounts presented include the minimum required capital levels as of March 31, 2015 based on the phased-in provisions of the Basel III Capital Rules and the minimum required capital levels as of January 1, 2019 when the Basel III Capital Rules have been fully phased-in. Capital levels required to be considered well capitalized are based upon prompt corrective action regulations, as amended to reflect the changes under the Basel III Capital Rules.
		Actual					Minimum Capital					Minimum Capital					Required to be
							Required – Basel III					Required – Basel III					Considered Well
							Phase-in Schedule					Fully Phased In					Capitalized
		Amount		Ratio			Amount		Ratio			Amount		Ratio			Amount		Ratio
		(dollars in thousands)
	As of March 31, 2015:
	Total Capital
	(to Risk Weighted Assets):
	Consolidated	$	444,192		15.23	%	$	233,279		8	%	$	306,178		10.5	%	$	291,598		10	%
	Tri Counties Bank	$	442,590		15.19	%	$	233,138		8	%	$	305,993		10.5	%	$	291,422		10	%
	Tier 1 Capital
	(to Risk Weighted Assets):
	Consolidated	$	407,722		13.98	%	$	174,959		6	%	$	247,858		8.5	%	$	233,279		8	%
	Tri Counties Bank	$	406,142		13.94	%	$	174,853		6	%	$	247,709		8.5	%	$	233,138		8	%
	Common equity Tier 1 Capital
	(to Risk Weighted Assets):
	Consolidated	$	353,131		12.11	%	$	131,219		4.5	%	$	204,119		7	%	$	189,539		6.5	%
	Tri Counties Bank	$	406,142		13.94	%	$	131,140		4.5	%	$	203,996		7	%	$	189,424		6.5	%
	Tier 1 Capital (to Average Assets):
	Consolidated	$	407,722		10.68	%	$	152,748		4	%	$	152,748		4	%	$	190,935		5	%
	Tri Counties Bank	$	406,142		10.64	%	$	152,676		4	%	$	152,676		4	%	$	190,845		5	%
	The following table presents actual and required capital ratios as of December 31, 2014 for the Company and the Bank under the regulatory capital rules then in effect.
		Actual					Minimum					Minimum
							Capital Requirement					To Be Well
												Capitalized Under
												Prompt Corrective
												Action Provisions
		Amount		Ratio			Amount		Ratio			Amount		Ratio
		(dollars in thousands)
	As of December 31, 2014:
	Total Capital (to Risk Weighted Assets):
	Consolidated	$	436,955		15.63	%	$	223,603		8	%		N/A		N/A
	Tri Counties Bank	$	433,286		15.51	%	$	223,449		8	%	$	279,311		10	%
	Tier 1 Capital (to Risk Weighted Assets):
	Consolidated	$	401,971		14.38	%	$	111,801		4	%		N/A		N/A
	Tri Counties Bank	$	398,325		14.26	%	$	111,724		4	%	$	167,587		6	%
	Tier 1 Capital (to Average Assets):
	Consolidated	$	401,971		10.8	%	$	148,819		4	%		N/A		N/A
	Tri Counties Bank	$	398,325		10.71	%	$	148,734		4	%	$	185,918		5	%
	As of March 31, 2015, capital levels at the Company and the Bank exceed all capital adequacy requirements under the Basel III Capital Rules on a fully phased-in basis. Based on the ratios presented above, capital levels as March 31, 2015 at the Company and the Bank exceed the minimum levels necessary to be considered “well capitalized”.

Summary_of_Quarterly_Results_o

Summary of Quarterly Results of Operations (unaudited)	3 Months Ended
	Mar. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of Quarterly Results of Operations (unaudited)	Note 30 – Summary of Quarterly Results of Operations (unaudited)
	The following table sets forth the results of operations for the periods indicated, and is unaudited; however, in the opinion of Management, it reflects all adjustments (which include only normal recurring adjustments) necessary to present fairly the summarized results for such periods.
		2015 Quarters Ended
		December 31,			September 30,			June 30,		March 31,
		(dollars in thousands, except per share data)
	Interest and dividend income:
	Loans:
	Discount accretion PCI – cash basis									$	172
	Discount accretion PCI – other										1,274
	Discount accretion PNCI										1,348
	All other loan interest income										28,371
	Total loan interest income										31,165
	Debt securities, dividends and interest bearing cash at Banks (not FTE)										6,560
	Total interest income										37,725
	Interest expense										1,382
	Net interest income										36,343
	(Benefit from) provision for loan losses										197
	Net interest income after provision for loan losses										36,146
	Noninterest income										10,180
	Noninterest expense										32,282
	Income before income taxes										14,044
	Income tax expense										5,708
	Net income									$	8,336
	Per common share:
	Net income (diluted)									$	0.36
	Dividends									$	0.11
		2014 Quarters Ended
		December 31,			September 30,			June 30,		March 31,
		(dollars in thousands, except per share data)
	Interest and dividend income:
	Loans:
	Discount accretion PCI – cash basis	$	107		$	290		$	69	$	203
	Discount accretion PCI – other		919			822			811		984
	Discount accretion PNCI		796			402			624		379
	All other loan interest income		28,914			23,466			22,929		22,172
	Total loan interest income		30,736			24,980			24,433		23,738
	Debt securities, dividends and interest bearing cash at Banks (not FTE)		5,671			4,151			3,985		3,421
	Total interest income		36,407			29,131			28,418		27,159
	Interest expense		1,437			1,082			1,075		1,087
	Net interest income		34,970			28,049			27,343		26,072
	(Benefit from) provision for loan losses		(1,421	)		(2,977	)		1,708		(1,355	)
	Net interest income after provision for loan losses		36,391			31,026			25,635		27,427
	Noninterest income		9,755			8,589			7,877		8,295
	Noninterest expense		36,566			25,380			25,116		23,317
	Income before income taxes		9,580			14,235			8,396		12,405
	Income tax expense		3,930			6,001			3,537		5,040
	Net income	$	5,650		$	8,234		$	4,859	$	7,365
	Per common share:
	Net income (diluted)	$	0.25		$	0.5		$	0.3	$	0.45
	Dividends	$	0.11		$	0.11		$	0.11	$	0.11

Subsequent_Event

Subsequent Event	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Event	Note – 31 Subsequent Event
	On April 29, 2015, the Company issued a press release announcing its earnings for the three months ended March 31, 2015. Included in that announcement was a statement by the Company that following a thorough analysis of profitability and market opportunity, the bank has identified five additional branches for closure. Two of those branches are former North Valley Bank branches. The bank expects that all five branches will close by September 30, 2015.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation
	TriCo Bancshares (the “Company”) is a California corporation organized to act as a bank holding company for Tri Counties Bank (the “Bank”). The Company and the Bank are headquartered in Chico, California. The Bank is a California-chartered bank that is engaged in the general commercial banking business in 26 California counties. Tri Counties Bank currently operates from 57 traditional branches and 16 in-store branches. The Company has five capital subsidiary business trusts (collectively, the Capital Trusts) that issued trust preferred securities, including two organized by TriCo and three acquired with the acquisition of North Valley Bancorp. See Note 17 – Junior Subordinated Debt.
	The consolidated financial statements are prepared in accordance with accounting policies generally accepted in the United States of America and general practices in the banking industry. The financial statements include the accounts of the Company. All inter-company accounts and transactions have been eliminated in consolidation. For financial reporting purposes, the Company’s investments in the Capital Trusts of $1,691,000 are accounted for under the equity method and, accordingly, are not consolidated and are included in other assets on the consolidated balance sheet. The subordinated debentures issued and guaranteed by the Company and held by the Capital Trusts are reflected as debt on the Company’s consolidated balance sheet.
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements
	The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. The Company evaluates its estimates on an on-going basis. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.
	As described in Note 2, the Company acquired North Valley Bancorp on October 3, 2014. The acquired assets and assumed liabilities were measured at estimated fair value values under the acquisition method of accounting. The Company made significant estimates and exercised significant judgment in accounting for the acquisition. The Company determined loan fair values based on loan file reviews, loan risk ratings, appraised collateral values, expected cash flows and historical loss factors. Foreclosed assets were primarily valued based on appraised values of the repossessed loan collateral. Land and building were valued based on appraised values. An identifiable intangible was also recorded representing the fair value of the core deposit customer base based on an evaluation of the cost of such deposits relative to alternative funding sources. The fair value of time deposits and borrowings were determined based on the present value of estimated future cash flows using current rates as of the acquisition date.
Significant Group Concentration of Credit Risk	Significant Group Concentration of Credit Risk
	The Company grants agribusiness, commercial, consumer, and residential loans to customers located throughout the northern San Joaquin Valley, the Sacramento Valley and northern mountain regions of California. The Company has a diversified loan portfolio within the business segments located in this geographical area. The Company currently classifies all its operation into one business segment that it denotes as community banking.
Cash and Cash Equivalents	Cash and Cash Equivalents
	For purposes of the consolidated statements of cash flows, cash and cash equivalents include cash on hand, amounts due from banks, and federal funds sold. Net cash flows are reported for loan and deposit transactions and other borrowings.
Investment Securities	Investment Securities
	The Company classifies its debt and marketable equity securities into one of three categories: trading, available for sale or held to maturity. Trading securities are bought and held principally for the purpose of selling in the near term. Held to maturity securities are those securities which the Company has the ability and intent to hold until maturity. These securities are carried at cost adjusted for amortization of premium and accretion of discount, computed by the effective interest method over their contractual lives. All other securities not included in trading or held to maturity are classified as available for sale. Available for sale securities are recorded at fair value. Unrealized gains and losses, net of the related tax effect, on available for sale securities are reported as a separate component of other accumulated comprehensive income in shareholders’ equity until realized. Premiums and discounts are amortized or accreted over the life of the related investment security as an adjustment to yield using the effective interest method. Dividend and interest income are recognized when earned. Realized gains and losses are derived from the amortized cost of the security sold. During the three months ended March 31, 2015, and the year ended December 31, 2014, the Company did not have any securities classified as trading.
	The Company assesses other-than-temporary impairment (“OTTI”) based on whether it intends to sell a security or if it is likely that the Company would be required to sell the security before recovery of the amortized cost basis of the investment, which may be maturity. For debt securities, if we intend to sell the security or it is likely that we will be required to sell the security before recovering its cost basis, the entire impairment loss would be recognized in earnings as an OTTI. If we do not intend to sell the security and it is not likely that we will be required to sell the security but we do not expect to recover the entire amortized cost basis of the security, only the portion of the impairment loss representing credit losses would be recognized in earnings. The credit loss on a security is measured as the difference between the amortized cost basis and the present value of the cash flows expected to be collected. Projected cash flows are discounted by the original or current effective interest rate depending on the nature of the security being measured for potential OTTI. The remaining impairment related to all other factors, the difference between the present value of the cash flows expected to be collected and fair value, is recognized as a charge to other comprehensive income (“OCI”). Impairment losses related to all other factors are presented as separate categories within OCI. The accretion of the amount recorded in OCI increases the carrying value of the investment and does not affect earnings. If there is an indication of additional credit losses the security is re-evaluated according to the procedures described above. No OTTI losses were recognized during the three months ended March 31, 2015 or the year ended December 31, 2014.
Restricted Equity Securities	Restricted Equity Securities
	Restricted equity securities represent the Company’s investment in the stock of the Federal Home Loan Bank of San Francisco (“FHLB”) and are carried at par value, which reasonably approximates its fair value. While technically these are considered equity securities, there is no market for the FHLB stock. Therefore, the shares are considered as restricted investment securities. Management periodically evaluates FHLB stock for other-than-temporary impairment. Management’s determination of whether these investments are impaired is based on its assessment of the ultimate recoverability of cost rather than by recognizing temporary declines in value. The determination of whether a decline affects the ultimate recoverability of cost is influenced by criteria such as (1) the significance of any decline in net assets of the FHLB as compared to the capital stock amount for the FHLB and the length of time this situation has persisted, (2) commitments by the FHLB to make payments required by law or regulation and the level of such payments in relation to the operating performance of the FHLB, (3) the impact of legislative and regulatory changes on institutions and, accordingly, the customer base of the FHLB, and (4) the liquidity position of the FHLB.
	As a member of the FHLB system, the Company is required to maintain a minimum level of investment in FHLB stock based on specific percentages of its outstanding mortgages, total assets, or FHLB advances. The Company may request redemption at par value of any stock in excess of the minimum required investment. Stock redemptions are at the discretion of the FHLB.
Loans Held for Sale	Loans Held for Sale
	Loans originated and intended for sale in the secondary market are carried at the lower of aggregate cost or fair value, as determined by aggregate outstanding commitments from investors of current investor yield requirements. Net unrealized losses are recognized through a valuation allowance by charges to noninterest income.
	Mortgage loans held for sale are generally sold with the mortgage servicing rights retained by the Company. Gains or losses on the sale of loans that are held for sale are recognized at the time of the sale and determined by the difference between net sale proceeds and the net book value of the loans less the estimated fair value of any retained mortgage servicing rights.
Loans and Allowance for Loan Losses	Loans and Allowance for Loan Losses
	Loans originated by the Company, i.e., not purchased or acquired in a business combination, are referred to as originated loans. Originated loans that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are reported at the principal amount outstanding, net of deferred loan fees and costs. Loan origination and commitment fees and certain direct loan origination costs are deferred, and the net amount is amortized as an adjustment of the related loan’s yield over the actual life of the loan. Originated loans on which the accrual of interest has been discontinued are designated as nonaccrual loans.
	Originated loans are placed in nonaccrual status when reasonable doubt exists as to the full, timely collection of interest or principal, or a loan becomes contractually past due by 90 days or more with respect to interest or principal and is not well secured and in the process of collection. When an originated loan is placed on nonaccrual status, all interest previously accrued but not collected is reversed. Income on such loans is then recognized only to the extent that cash is received and where the future collection of principal is probable. Interest accruals are resumed on such loans only when they are brought fully current with respect to interest and principal and when, in the judgment of Management, the loan is estimated to be fully collectible as to both principal and interest.
	An allowance for loan losses for originated loans is established through a provision for loan losses charged to expense. The allowance is maintained at a level which, in Management’s judgment, is adequate to absorb probable incurred credit losses inherent in the loan portfolio as of the balance sheet date. Originated loans and deposit related overdrafts are charged against the allowance for loan losses when Management believes that the collectability of the principal is unlikely or, with respect to consumer installment loans, according to an established delinquency schedule. The allowance is an amount that Management believes will be adequate to absorb probable incurred losses inherent in existing loans, based on evaluations of the collectability, impairment and prior loss experience of loans. The evaluations take into consideration such factors as changes in the nature and size of the portfolio, overall portfolio quality, loan concentrations, specific problem loans, and current economic conditions that may affect the borrower’s ability to pay. The Company defines an originated loan as impaired when it is probable the Company will be unable to collect all amounts due according to the contractual terms of the loan agreement. Impaired originated loans are measured based on the present value of expected future cash flows discounted at the loan’s original effective interest rate. As a practical expedient, impairment may be measured based on the loan’s observable market price or the fair value of the collateral if the loan is collateral dependent. When the measure of the impaired loan is less than the recorded investment in the loan, the impairment is recorded through a valuation allowance.
	In situations related to originated loans where, for economic or legal reasons related to a borrower’s financial difficulties, the Company grants a concession for other than an insignificant period of time to the borrower that the Company would not otherwise consider, the related loan is classified as a troubled debt restructuring (TDR). The Company strives to identify borrowers in financial difficulty early and work with them to modify to more affordable terms before their loan reaches nonaccrual status. These modified terms may include rate reductions, principal forgiveness, payment forbearance and other actions intended to minimize the economic loss and to avoid foreclosure or repossession of the collateral. In cases where the Company grants the borrower new terms that result in the loan being classified as a TDR, the Company measures any impairment on the restructuring as noted above for impaired loans. TDR loans are classified as impaired until they are fully paid off or charged off. Loans that are in nonaccrual status at the time they become TDR loans, remain in nonaccrual status until the borrower demonstrates a sustained period of performance which the Company generally believes to be six consecutive months of payments, or equivalent. Otherwise, TDR loans are subject to the same nonaccrual and charge-off policies as noted above with respect to their restructured principal balance.
	Credit risk is inherent in the business of lending. As a result, the Company maintains an allowance for loan losses to absorb probable incurred losses inherent in the Company’s originated loan portfolio. This is maintained through periodic charges to earnings. These charges are included in the Consolidated Statements of Income as provision for loan losses. All specifically identifiable and quantifiable losses are immediately charged off against the allowance. However, for a variety of reasons, not all losses are immediately known to the Company and, of those that are known, the full extent of the loss may not be quantifiable at that point in time. The balance of the Company’s allowance for originated loan losses is meant to be an estimate of these unknown but probable losses inherent in the portfolio.
	The Company formally assesses the adequacy of the allowance for originated loan losses on a quarterly basis. Determination of the adequacy is based on ongoing assessments of the probable risk in the outstanding originated loan portfolio, and to a lesser extent the Company’s originated loan commitments. These assessments include the periodic re-grading of credits based on changes in their individual credit characteristics including delinquency, seasoning, recent financial performance of the borrower, economic factors, changes in the interest rate environment, growth of the portfolio as a whole or by segment, and other factors as warranted. Loans are initially graded when originated. They are re-graded as they are renewed, when there is a new loan to the same borrower, when identified facts demonstrate heightened risk of nonpayment, or if they become delinquent. Re-grading of larger problem loans occurs at least quarterly. Confirmation of the quality of the grading process is obtained by independent credit reviews conducted by consultants specifically hired for this purpose and by various bank regulatory agencies.
	The Company’s method for assessing the appropriateness of the allowance for originated loan losses includes specific allowances for impaired originated loans, formula allowance factors for pools of credits, and allowances for changing environmental factors (e.g., interest rates, growth, economic conditions, etc.). Allowance factors for loan pools were based on historical loss experience by product type and prior risk rating.
	During the three months ended March 31, 2014, the Company modified its methodology used to determine the allowance for changing environmental factors by adding a new environmental factor based on the California Home Affordability Index (“CHAI”). The CHAI measures the percentage of households in California that can afford to purchase the median priced home in California based on current home prices and mortgage interest rates. The use of the CHAI environmental factor consists of comparing the current CHAI to its historical baseline, and allows management to consider the adverse impact that a lower than historical CHAI may have on general economic activity and the performance of our borrowers. Based on an analysis of historical data, management believes this environmental factor gives a better estimate of current economic activity compared to other environmental factors that may lag current economic activity to some extent. This change in methodology resulted in no change to the allowance for loan losses as of March 31, 2014 compared to what it would have been without this change in methodology.
	During the three months ended June 30, 2014, the Company refined the method it uses to evaluate historical losses for the purpose of estimating the pool allowance for unimpaired loans. In the third quarter of 2010, the Company moved from a six point grading system (Grades A-F) to a nine point risk rating system (Risk Ratings 1-9), primarily to allow for more distinction within the “Pass” risk rating. Initially, there was not sufficient loss experience within the nine point scale to complete a migration analysis for all nine risk ratings, all loans risk rated Pass or 2-5 were grouped together, a loss rate was calculated for that group, and that loss rate was established as the loss rate for risk rating 4. The reserve ratios for risk ratings 2, 3 and 5 were then interpolated from that figure. As of June 30, 2014, the Company was able to compile twelve quarters of historical loss information for all risk ratings and use that information to calculate the loss rates for each of the nine risk ratings without interpolation. This refinement led to an increase of $1,438,000 in the reserve requirement for unimpaired loans, driven primarily by home equity lines of credit with a risk rating of 5 or “Pass-Watch.”
	Loans purchased or acquired in a business combination are referred to as acquired loans. Acquired loans are valued as of the acquisition date in accordance with Financial Accounting Standards Board Accounting Standards Codification (“FASB ASC”) Topic 805, Business Combinations. Loans acquired with evidence of credit deterioration since origination for which it is probable that all contractually required payments will not be collected are referred to as purchased credit impaired (PCI) loans. PCI loans are accounted for under FASB ASC Topic 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality. Under FASB ASC Topic 805 and FASB ASC Topic 310-30, PCI loans are recorded at fair value at acquisition date, factoring in credit losses expected to be incurred over the life of the loan. Accordingly, an allowance for loan losses is not carried over or recorded as of the acquisition date. Fair value is defined as the present value of the future estimated principal and interest payments of the loan, with the discount rate used in the present value calculation representing the estimated effective yield of the loan. Default rates, loss severity, and prepayment speed assumptions are periodically reassessed and our estimate of future payments is adjusted accordingly. The difference between contractual future payments and estimated future payments is referred to as the nonaccretable difference. The difference between estimated future payments and the present value of the estimated future payments is referred to as the accretable yield. The accretable yield represents the amount that is expected to be recorded as interest income over the remaining life of the loan. If after acquisition, the Company determines that the estimated future cash flows of a PCI loan are expected to be more than originally estimated, an increase in the discount rate (effective yield) would be made such that the newly increased accretable yield would be recognized, on a level yield basis, over the remaining estimated life of the loan. If, after acquisition, the Company determines that the estimated future cash flows of a PCI loan are expected to be less than previously estimated, the discount rate would first be reduced until the present value of the reduced cash flow estimate equals the previous present value however, the discount rate may not be lowered below its original level at acquisition. If the discount rate has been lowered to its original level and the present value has not been sufficiently lowered, an allowance for loan loss would be established through a provision for loan losses charged to expense to decrease the present value to the required level. If the estimated cash flows improve after an allowance has been established for a loan, the allowance may be partially or fully reversed depending on the improvement in the estimated cash flows. Only after the allowance has been fully reversed may the discount rate be increased. PCI loans are put on nonaccrual status when cash flows cannot be reasonably estimated. PCI loans on nonaccrual status are accounted for using the cost recovery method or cash basis method of income recognition. The Company refers to PCI loans on nonaccrual status that are accounted for using the cash basis method of income recognition as “PCI – cash basis” loans; and the Company refers to all other PCI loans as “PCI – other” loans PCI loans are charged off when evidence suggests cash flows are not recoverable. Foreclosed assets from PCI loans are recorded in foreclosed assets at fair value with the fair value at time of foreclosure representing cash flow from the loan. ASC 310-30 allows PCI loans with similar risk characteristics and acquisition time frame to be “pooled” and have their cash flows aggregated as if they were one loan. The Company elected to use the “pooled” method of ASC 310-30 for PCI – other loans in the acquisition of certain assets and liabilities of Granite Community Bank, N.A. (“Granite”) during 2010 and Citizens Bank of Northern California (“Citizens”) during 2011.
	Acquired loans that are not PCI loans are referred to as purchased not credit impaired (PNCI) loans. PNCI loans are accounted for under FASB ASC Topic 310-20, Receivables – Nonrefundable Fees and Other Costs, in which interest income is accrued on a level-yield basis for performing loans. For income recognition purposes, this method assumes that all contractual cash flows will be collected, and no allowance for loan losses is established at the time of acquisition. Post-acquisition date, an allowance for loan losses may need to be established for acquired loans through a provision charged to earnings for credit losses incurred subsequent to acquisition. Under ASC 310-20, the loss would be measured based on the probable shortfall in relation to the contractual note requirements, consistent with our allowance for loan loss policy for similar loans.
	Throughout these financial statements, and in particular in Note 4 and Note 5, when we refer to “Loans” or “Allowance for loan losses” we mean all categories of loans, including Originated, PNCI, PCI – cash basis, and PCI - other. When we are not referring to all categories of loans, we will indicate which we are referring to – Originated, PNCI, PCI – cash basis, or PCI - other.
	When referring to PNCI and PCI loans we use the terms “nonaccretable difference”, “accretable yield”, or “purchase discount”. Nonaccretable difference is the difference between undiscounted contractual cash flows due and undiscounted cash flows we expect to collect, or put another way, it is the undiscounted contractual cash flows we do not expect to collect. Accretable yield is the difference between undiscounted cash flows we expect to collect and the value at which we have recorded the loan on our financial statements. On the date of acquisition, all purchased loans are recorded on our consolidated financial statements at estimated fair value. Purchase discount is the difference between the estimated fair value of loans on the date of acquisition and the principal amount owed by the borrower, net of charge offs, on the date of acquisition. We may also refer to “discounts to principal balance of loans owed, net of charge-offs”. Discounts to principal balance of loans owed, net of charge-offs is the difference between principal balance of loans owed, net of charge-offs, and loans as recorded on our financial statements. Discounts to principal balance of loans owed, net of charge-offs arise from purchase discounts, and equal the purchase discount on the acquisition date.
	Loans are also categorized as “covered” or “noncovered”. Covered loans refer to loans covered by a Federal Deposit Insurance Corporation (“FDIC”) loss sharing agreement. Noncovered loans refer to loans not covered by a FDIC loss sharing agreement.
Foreclosed Assets	Foreclosed Assets
	Foreclosed assets include assets acquired through, or in lieu of, loan foreclosure. Foreclosed assets are held for sale and are initially recorded at fair value less estimated costs to sell at the date of foreclosure, establishing a new cost basis. Subsequent to foreclosure, management periodically performs valuations and the assets are carried at the lower of carrying amount or fair value less cost to sell. Revenue and expenses from operations and changes in the valuation allowance are included in other noninterest expense. Gain or loss on sale of foreclosed assets is included in noninterest income. Foreclosed assets that are not subject to a FDIC loss-share agreement are referred to as noncovered foreclosed assets.
	Foreclosed assets acquired through FDIC-assisted acquisitions that are subject to a FDIC loss-share agreement, and all assets acquired via foreclosure of covered loans are referred to as covered foreclosed assets. Covered foreclosed assets are reported exclusive of expected reimbursement cash flows from the FDIC. Foreclosed covered loan collateral is transferred into covered foreclosed assets at the loan’s carrying value, inclusive of the acquisition date fair value discount.
	Covered foreclosed assets are initially recorded at estimated fair value less estimated costs to sell on the acquisition date based on similar market comparable valuations less estimated selling costs. Any subsequent valuation adjustments due to declines in fair value will be charged to noninterest expense, and will be mostly offset by noninterest income representing the corresponding increase to the FDIC indemnification asset for the offsetting loss reimbursement amount. Any recoveries of previous valuation adjustments will be credited to noninterest expense with a corresponding charge to noninterest income for the portion of the recovery that is due to the FDIC.
Premises and Equipment	Premises and Equipment
	Land is carried at cost. Land improvements, buildings and equipment, including those acquired under capital lease, are stated at cost less accumulated depreciation and amortization. Depreciation and amortization expenses are computed using the straight-line method over the estimated useful lives of the related assets or lease terms. Asset lives range from 3-10 years for furniture and equipment and 15-40 years for land improvements and buildings.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets
	Goodwill represents the excess of costs over fair value of net assets of businesses acquired. Goodwill and other intangible assets acquired in a purchase business combination and determined to have an indefinite useful life are not amortized, but instead tested for impairment at least annually. Intangible assets with estimable useful lives are amortized over their respective estimated useful lives to their estimated residual values, and reviewed for impairment.
	The Company has an identifiable intangible asset consisting of core deposit intangibles (CDI). CDI are amortized over their respective estimated useful lives, and reviewed for impairment.
Impairment of Long-Lived Assets and Goodwill	Impairment of Long-Lived Assets and Goodwill
	Long-lived assets, such as premises and equipment, and purchased intangibles subject to amortization, are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Assets to be disposed of would be separately presented in the balance sheet and reported at the lower of the carrying amount or fair value less costs to sell, and are no longer depreciated. The assets and liabilities of a disposed group classified as held for sale would be presented separately in the appropriate asset and liability sections of the consolidated balance sheet.
	As of December 31 of each year, goodwill is tested for impairment, and is tested for impairment more frequently if events and circumstances indicate that the asset might be impaired. An impairment loss is recognized to the extent that the carrying amount exceeds the asset’s fair value. This determination is made at the reporting unit level. The Company may choose to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of a reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is not more likely than not that the fair value of a reporting unit is less than its carrying amount, then goodwill is deemed not to be impaired. However, if the Company concludes otherwise, or if the Company elected not to first assess qualitative factors, then the Company performs the first step of a two-step impairment test by calculating the fair value of the reporting unit and comparing the fair value with the carrying amount of the reporting unit. Second, if the carrying amount of the reporting unit exceeds its fair value, an impairment loss is recognized for any excess of the carrying amount of the reporting unit’s goodwill over the implied fair value of that goodwill. The implied fair value of goodwill is determined by allocating the fair value of the reporting unit in a manner similar to a purchase price allocation. The residual fair value after this allocation is the implied fair value of the reporting unit goodwill. Currently, and historically, the Company is comprised of only one reporting unit that operates within the business segment it has identified as “community banking”. Goodwill was not impaired as of December 31, 2014 because the fair value of the reporting unit exceeded its carrying value.
Mortgage Servicing Rights	Mortgage Servicing Rights
	Mortgage servicing rights (MSR) represent the Company’s right to a future stream of cash flows based upon the contractual servicing fee associated with servicing mortgage loans. Our MSR arise from residential and commercial mortgage loans that we originate and sell, but retain the right to service the loans. The net gain from the retention of the servicing right is included in gain on sale of loans in noninterest income when the loan is sold. Fair value is based on market prices for comparable mortgage servicing contracts, when available, or alternatively, is based on a valuation model that calculates the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, the custodial earnings rate, an inflation rate, ancillary income, prepayment speeds and default rates and losses. Servicing fees are recorded in noninterest income when earned.
	The Company accounts for MSR at fair value. The determination of fair value of our MSR requires management judgment because they are not actively traded. The determination of fair value for MSR requires valuation processes which combine the use of discounted cash flow models and extensive analysis of current market data to arrive at an estimate of fair value. The cash flow and prepayment assumptions used in our discounted cash flow model are based on empirical data drawn from the historical performance of our MSR, which we believe are consistent with assumptions used by market participants valuing similar MSR, and from data obtained on the performance of similar MSR. The key assumptions used in the valuation of MSR include mortgage prepayment speeds and the discount rate. These variables can, and generally will, change from quarter to quarter as market conditions and projected interest rates change. The key risks inherent with MSR are prepayment speed and changes in interest rates. The Company uses an independent third party to determine fair value of MSR.
Indemnification Asset/Liability	Indemnification Asset/Liability
	The Company accounts for amounts receivable or payable under its loss-share agreements entered into with the FDIC in connection with its purchase and assumption of certain assets and liabilities of Granite as indemnification assets in accordance with FASB ASC Topic 805, Business Combinations. FDIC indemnification assets are initially recorded at fair value, based on the discounted value of expected future cash flows under the loss-share agreements. The difference between the fair value and the undiscounted cash flows the Company expects to collect from or pay to the FDIC will be accreted into noninterest income over the life of the FDIC indemnification asset. FDIC indemnification assets are reviewed quarterly and adjusted for any changes in expected cash flows based on recent performance and expectations for future performance of the covered portfolios. These adjustments are measured on the same basis as the related covered loans and covered other real estate owned. Any increases in cash flow of the covered assets over those expected will reduce the FDIC indemnification asset and any decreases in cash flow of the covered assets under those expected will increase the FDIC indemnification asset. Increases and decreases to the FDIC indemnification asset are recorded as adjustments to noninterest income.
Reserve for Unfunded Commitments	Reserve for Unfunded Commitments
	The reserve for unfunded commitments is established through a provision for losses – unfunded commitments charged to noninterest expense. The reserve for unfunded commitments is an amount that Management believes will be adequate to absorb probable losses inherent in existing commitments, including unused portions of revolving lines of credits and other loans, standby letters of credits, and unused deposit account overdraft privilege. The reserve for unfunded commitments is based on evaluations of the collectability, and prior loss experience of unfunded commitments. The evaluations take into consideration such factors as changes in the nature and size of the loan portfolio, overall loan portfolio quality, loan concentrations, specific problem loans and related unfunded commitments, and current economic conditions that may affect the borrower’s or depositor’s ability to pay.
Income Taxes	Income Taxes
	The Company’s accounting for income taxes is based on an asset and liability approach. The Company recognizes the amount of taxes payable or refundable for the current year, and deferred tax assets and liabilities for the future tax consequences that have been recognized in its financial statements or tax returns. The measurement of tax assets and liabilities is based on the provisions of enacted tax laws. A valuation allowance, if needed, reduces deferred tax assets to the expected amount most likely to be realized. Realization of deferred tax assets is dependent upon the generation of a sufficient level of future taxable income and recoverable taxes paid in prior years. Although realization is not assured, management believes it is more likely than not that all of the deferred tax assets will be realized. Interest and/or penalties related to income taxes are reported as a component of noninterest income.
Off-Balance Sheet Credit Related Financial Instruments	Off-Balance Sheet Credit Related Financial Instruments
	In the ordinary course of business, the Company has entered into commitments to extend credit, including commitments under credit card arrangements, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded when they are funded.
Geographical Descriptions	Geographical Descriptions
	For the purpose of describing the geographical location of the Company’s loans, the Company has defined northern California as that area of California north of, and including, Stockton; central California as that area of the state south of Stockton, to and including, Bakersfield; and southern California as that area of the state south of Bakersfield.
Reclassifications	Reclassifications
	Certain amounts reported in previous consolidated financial statements have been reclassified to conform to the presentation in this report. These reclassifications did not affect previously reported net income or total shareholders’ equity.
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	FASB issued ASU No. 2014-04, Receivables (Topic 310): Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. ASU 2014-04 clarifies when an in substance repossession or foreclosure occurs, that is, when a creditor should be considered to have received physical possession of residential real estate property collateralizing a consumer mortgage loan such that the loan receivable should be derecognized and the real estate property recognized. ASU 2014-04 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
	FASB issued ASU No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity. ASU 2014-08 improves the definition of discontinued operations by limiting discontinued operations reporting to disposals of components of an entity that represent strategic shifts that have (or will have) a major effect on an entity’s operations and financial results. ASU 2014-08 requires expanded disclosures for discontinued operations that provide users of financial statements with more information about the assets, liabilities, revenues, and expenses of discontinued operations. ASU 2014-08 also requires an entity to disclose the pretax profit or loss of an individually significant component of an entity that does not qualify for discontinued operations reporting, and provide users with information about the financial effects of significant disposals that do not qualify for discontinued operations reporting. The amendments in ASU 2014-08 include several changes to the Accounting Standards Codification to improve the organization and readability of Subtopic 205-20 and Subtopic 360-10, Property, Plant, and Equipment—Overall. ASU 2014-08 is effective for public business entities for annual periods, and interim periods within those annual periods, beginning after December 15, 2014. ASU 2014-08 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
	FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606). The core principle of the guidance under ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. ASU 2014-09 is effective for a public entity for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period. Early application is not permitted. ASU 2014-09 is not expected to have a significant impact on the Company’s consolidated financial statements.
	FASB issued ASU No. 2014-11, Transfers and Servicing (Topic 860): Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures. ASU 2014-11 requires that repurchase-to-maturity transactions be accounted for as secured borrowings consistent with the accounting for other repurchase agreements. In addition, ASU 2014-11 requires separate accounting for repurchase financings, which entails the transfer of a financial asset executed contemporaneously with a repurchase agreement with the same counterparty. ASU 2014-11 requires entities to disclose certain information about transfers accounted for as sales in transactions that are economically similar to repurchase agreements. In addition, ASU 2014-11 requires disclosures related to collateral, remaining contractual tenor and of the potential risks associated with repurchase agreements, securities lending transactions and repurchase-to-maturity transactions. ASU 2014-11 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.
	FASB issued ASU No. 2014-12, Compensation—Stock Compensation (Topic 718): Accounting for Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be achieved after the Requisite Service Period. ASU 2014-12 requires that a performance target that affects the vesting of a share-based payment award and that could be achieved after the requisite service period be treated as a performance condition. A reporting entity should apply existing guidance in Topic 718 as it relates to awards with performance conditions that affect vesting to account for such awards. As such, the performance target should not be reflected in estimating the grant-date fair value of the award. Compensation cost should be recognized in the period in which it becomes probable that the performance target will be achieved and should represent the compensation cost attributable to the period(s) for which the requisite service has already been rendered. If the performance target becomes probable of being achieved before the end of the requisite service period, the remaining unrecognized compensation cost should be recognized prospectively over the remaining requisite service period. The total amount of compensation cost recognized during and after the requisite service period should reflect the number of awards that are expected to vest and should be adjusted to reflect those awards that ultimately vest. The requisite service period ends when the employee can cease rendering service and still be eligible to vest in the award if the performance target is achieved. The stated vesting period (which includes the period in which the performance target could be achieved) may differ from the requisite service period. Current U.S. GAAP does not contain explicit guidance on whether to treat a performance target that could be achieved after the requisite service period as a performance condition that affects vesting or as a nonvesting condition that affects the grant-date fair value of an award. ASU 2014-12 provides explicit guidance for those awards. For all entities, ASU 2014-12 is effective for annual periods and interim periods within those annual periods beginning after December 15, 2015. Earlier adoption is permitted. The Company has elected to not adopt ASU 2014-12 early.
	FASB issued ASU No. 2014-14, Receivables—Troubled Debt Restructurings by Creditors (Topic 310): Classification of Certain Government Mortgage Loans upon Foreclosure. ASU 2014-14 requires that a mortgage loan be derecognized and that a separate other receivable be recognized upon foreclosure if the following conditions are met: 1) the loan has a government guarantee that is not separable from the loan before foreclosure, 2) at the time of foreclosure, the creditor has the intent to convey the real estate property to the guarantor and make a claim on the guarantee, and the creditor has the ability to recover under that claim, and 3) at the time of foreclosure, any amount of the claim that is determined on the basis of the fair value of the real estate is fixed. Upon foreclosure, the separate other receivable should be measured based on the amount of the loan balance (principal and interest) expected to be recovered from the guarantor. ASU 2014-14 became effective for the Company on January 1, 2015, and did not have a significant impact on the Company’s consolidated financial statements.

Business_Combinations_Tables

Business Combinations (Tables)	3 Months Ended
	Mar. 31, 2015
Summary of Principal Balance Loans Acquired	The following table presents a reconciliation of the undiscounted contractual cash flows, nonaccretable difference, accretable yield, fair value, purchase discount, and principal balance of loans for the PNCI and PCI – other categories of North Valley Bancorp loans as of the acquisition date. For North Valley Bancorp PCI – other loans, the purchase discount does not necessarily represent cash flows to be collected:
		North Valley Bancorp Loans – October 3, 2014
	(in thousands)	PNCI			PCI – other			Total
	Undiscounted contractual cash flows	$	718,731		$	15,706		$	734,437
	Undiscounted cash flows not expected to be collected (nonaccretable difference)		—			(6,295	)		(6,295	)
	Undiscounted cash flows expected to be collected		718,731			9,411			728,142
	Accretable yield at acquisition		(228,815	)		—			(228,815	)
	Estimated fair value of loans acquired at acquisition		489,916			9,411			499,327
	Purchase discount		12,721			2,077			14,798
	Principal balance loans acquired	$	502,637		$	11,488		$	514,125
North Valley Bancorp [Member]
Schedule of Fair Value of Consideration Transferred, Identifiable Net Assets Acquired and Resulting Goodwill	The following table discloses the calculation of the fair value of consideration transferred, the total identifiable net assets acquired and the resulting goodwill relating to the North Valley Bancorp acquisition:
	(in thousands)	North Valley Bancorp
		October 3, 2014
	Fair value of consideration transferred:
	Fair value of shares issued	$	151,303
	Cash consideration		7
	Total fair value of consideration transferred		151,310
	Asset acquired:
	Cash and cash equivalents		141,412
	Securities available for sale		17,288
	Securities held to maturity		189,950
	Restricted equity securities		5,378
	Loans		499,327
	Foreclosed assets		695
	Premises and equipment		11,936
	Cash value of life insurance		38,075
	Core deposit intangible		6,614
	Other assets		20,064
	Total assets acquired		930,739
	Liabilities assumed:
	Deposits		801,956
	Other liabilities		10,429
	Junior subordinated debt		14,987
	Total liabilities assumed		827,372
	Total net assets acquired		103,367
	Goodwill recognized	$	47,943
Summary of Estimated Fair Value Adjustments Resulting In Goodwill	A summary of the estimated fair value adjustments resulting in the goodwill recorded in the North Valley Bancorp acquisition are presented below:
	(in thousands)	North Valley Bancorp
		October 3, 2014
	Value of stock consideration paid to North Valley Bancorp Shareholders	$	151,303
	Cash payments to North Valley Bancorp Shareholders		7
	Cost basis net assets acquired		(98,040	)
	Fair value adjustments:
	Loans		5,832
	Premises and Equipment		(4,785	)
	Core deposit intangible		(6,283	)
	Deferred income taxes		6,293
	Junior subordinated debt		(6,664	)
	Other		280
	Goodwill	$	47,943
Schedule of Cost Basis, Fair Value Discount and loan Acquired	The following table presents the cost basis, fair value discount, and fair value of loans acquired from North Valley Bancorp on October 3, 2014:
		North Valley Bancorp Acquired Loans
		3-Oct-14
	(in thousands)	Cost Basis			Discount			Fair Value
	PNCI	$	502,637		$	(12,721	)	$	489,916
	PCI – other		11,488			(2,077	)		9,411
	Total	$	514,125		$	(14,798	)	$	499,327

Investment_Securities_Tables

Investment Securities (Tables)	3 Months Ended
	Mar. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Amortized Cost and Estimated Fair Values of Investments in Debt and Equity Securities	The amortized cost and estimated fair values of investments in debt and equity securities are summarized in the following tables:
		March 31, 2015
		Amortized		Gross			Gross			Estimated
		Cost		Unrealized			Unrealized			Fair
				Gains			Losses			Value
		(in thousands)
	Securities Available for Sale
	Obligations of U.S. government corporations and agencies	$	206,476	$	4,221		$	(162	)	$	210,535
	Obligations of states and political subdivisions		9,700		36			(80	)		9,656
	Corporate debt securities		1,895		10			—			1,905
	Marketable equity securities		3,000		30			—			3,030
	Total securities available for sale	$	221,071	$	4,297		$	(242	)	$	225,126
	Securities Held to Maturity
	Obligations of U.S. government corporations and agencies	$	786,889	$	15,726		$	(339	)	$	802,276
	Obligations of states and political subdivisions		15,593		95			(171	)		15,517
	Total securities held to maturity	$	802,482	$	15,821		$	(510	)	$	817,793
		December 31, 2014
		Amortized		Gross			Gross			Estimated
		Cost		Unrealized			Unrealized			Fair
				Gains			Losses			Value
		(in thousands)
	Securities Available for Sale
	Obligations of U.S. government corporations and agencies	$	71,144	$	4,001		$	(25	)	$	75,120
	Obligations of states and political subdivisions		3,130		45			—			3,175
	Corporate debt securities		1,891		17			—			1,908
	Marketable equity securities		3,000		2			—			3,002
	Total securities available for sale	$	79,165	$	4,065		$	(25	)	$	83,205
	Securities Held to Maturity
	Obligations of U.S. government corporations and agencies	$	660,836	$	13,055		$	(677	)	$	673,214
	Obligations of states and political subdivisions		15,590		130			(155	)		15,565
	Total securities held to maturity	$	676,426	$	13,185		$	(832	)	$	688,779
Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity	For purposes of the following table, the entire outstanding balance of these mortgage-backed securities issued by U.S. government corporations and agencies is categorized based on final maturity date.
	Investment Securities	Available for Sale					Held to Maturity
	(In thousands)	Amortized		Estimated			Amortized			Estimated
		Cost		Fair Value			Cost			Fair Value
	Due in one year	$	1,896	$	1,906			—			—
	Due after one year through five years		4,014		4,202			—			—
	Due after five years through ten years		31,848		33,332		$	1,125		$	1,134
	Due after ten years		183,313		185,686			801,357			816,659
	Totals	$	221,071	$	225,126		$	802,482		$	817,793
Gross Unrealized Losses on Investment	Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, were as follows:
		Less than 12 months					12 months or more						Total
		Fair		Unrealized			Fair			Unrealized			Fair		Unrealized
		Value		Loss			Value			Loss			Value		Loss
		(in thousands)
	March 31, 2015
	Securities Available for Sale:
	Obligations of U.S. government corporations and agencies	$	78,146	$	(162	)		—			—		$	78,146	$	(162	)
	Obligations of states and political subdivisions		6,422		(80	)		—			—			6,422		(80	)
	Corporate debt securities		—		—			—			—			—		—
	Marketable equity securities		—		—			—			—			—		—
	Total securities available-for-sale	$	84,568	$	(242	)		—			—		$	84,568	$	(242	)
	Securities Held to Maturity:
	Obligations of U.S. government corporations and agencies	$	162,549	$	(339	)		—			—		$	162,549	$	(339	)
	Obligations of states and political subdivisions		2,419		(27	)	$	1,075		$	(144	)		3,494		(171	)
	Corporate debt securities		—		—			—			—			—		—
	Total securities held-to-maturity	$	164,968	$	(366	)	$	1,075		$	(144	)	$	166,043	$	(510	)
		Less than 12 months					12 months or more						Total
		Fair		Unrealized			Fair			Unrealized			Fair		Unrealized
		Value		Loss			Value			Loss			Value		Loss
		(in thousands)
	December 31, 2014
	Securities Available for Sale:
	Obligations of U.S. government corporations and agencies	$	6,774	$	(25	)		—			—		$	6,774	$	(25	)
	Obligations of states and political subdivisions		—		—			—			—			—		—
	Corporate debt securities		—		—			—			—			—		—
	Marketable equity securities		—		—			—			—			—		—
	Total securities available-for-sale	$	6,774	$	(25	)		—			—		$	6,774	$	(25	)
	Securities Held to Maturity:
	Obligations of U.S. government corporations and agencies	$	335	$	(1	)	$	56,288		$	(676	)	$	56,623	$	(677	)
	Obligations of states and political subdivisions		1,600		(26	)		1,858			(129	)		3,458		(155	)
	Corporate debt securities		—		—			—			—			—		—
	Total securities held-to-maturity	$	1,935	$	(27	)	$	58,146		$	(805	)	$	60,081	$	(832	)

Loans_Tables

Loans (Tables)	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
Summary of Loan Balances	A summary of loan balances follows (in thousands):
		March 31, 2015
		Originated			PNCI			PCI -			PCI -			Total
								Cash basis			Other
	Mortgage loans on real estate:
	Residential 1-4 family	$	160,041		$	118,316			—		$	4,026		$	282,383
	Commercial		970,433			366,096			—			27,951			1,364,480
	Total mortgage loan on real estate		1,130,474			484,412			—			31,977			1,646,863
	Consumer:
	Home equity lines of credit		299,298			36,953			5,459			3,500			345,210
	Home equity loans		26,892			4,841			124			629			32,486
	Auto Indirect		32			—			—			—			32
	Other		28,740			4,189			—			70			32,999
	Total consumer loans		354,962			45,983			5,583			4,199			410,727
	Commercial		134,055			36,429			6			7,050			177,540
	Construction:
	Residential		23,664			15,705			—			736			40,105
	Commercial		32,558			13,090			—			—			45,648
	Total construction		56,222			28,795			—			736			85,753
	Total loans, net of deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Total principal balance of loans owed, net of charge-offs	$	1,680,523		$	612,382		$	14,592		$	51,785		$	2,359,282
	Unamortized net deferred loan fees		(4,810	)		—			—			—			(4,810	)
	Discounts to principal balance of loans owed, net of charge-offs		—			(16,763	)		(9,003	)		(7,823	)		(33,589	)
	Total loans, net of unamortized deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Noncovered loans	$	1,675,713		$	595,619		$	5,589		$	23,542		$	2,300,463
	Covered loans		—			—			—			20,420			20,420
	Total loans, net of unamortized deferred loan fees and discounts	$	1,675,713		$	595,619		$	5,589		$	43,962		$	2,320,883
	Allowance for loan losses	$	(30,032	)	$	(2,925	)	$	(340	)	$	(2,758	)	$	(36,055	)
	A summary of loan balances follows (in thousands):
		December 31, 2014
		Originated			PNCI			PCI -			PCI -			Total
								Cash basis			Other
	Mortgage loans on real estate:
	Residential 1-4 family	$	154,594		$	120,821			—		$	4,005		$	279,420
	Commercial		928,797			376,225			—			30,917			1,335,939
	Total mortgage loan on real estate		1,083,391			497,046			—			34,922			1,615,359
	Consumer:
	Home equity lines of credit		305,166			38,397		$	5,478			3,543			352,584
	Home equity loans		23,559			6,985			125			645			31,314
	Auto Indirect		112			—			—			—			112
	Other		28,230			4,770			—			74			33,074
	Total consumer loans		357,067			50,152			5,603			4,262			417,084
	Commercial		126,611			40,899			8			7,427			174,945
	Construction:
	Residential		21,135			16,808			—			675			38,618
	Commercial		24,545			11,973			—			—			36,518
	Total construction		45,680			28,781			—			675			75,136
	Total loans, net of deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Total principal balance of loans owed, net of charge-offs	$	1,617,542		$	634,490		$	14,805		$	56,016		$	2,322,853
	Unamortized net deferred loan fees		(4,793	)		—			—			—			(4,793	)
	Discounts to principal balance of loans owed, net of charge-offs		—			(17,612	)		(9,194	)		(8,730	)		(35,536	)
	Total loans, net of unamortized deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Noncovered loans	$	1,612,749		$	616,878		$	5,611		$	25,018		$	2,260,256
	Covered loans		—			—			—			22,268			22,268
	Total loans, net of unamortized deferred loan fees and discounts	$	1,612,749		$	616,878		$	5,611		$	47,286		$	2,282,524
	Allowance for loan losses	$	(29,860	)	$	(3,296	)	$	(348	)	$	(3,081	)	$	(36,585	)
Change in Accretable Yield for PCI	The following is a summary of the change in accretable yield for PCI – other loans during the periods indicated (in thousands):
		Three months ended March 31,
		2015			2014
	Change in accretable yield:
	Balance at beginning of period	$	14,159		$	18,232
	Accretion to interest income		(1,818	)		(1,631	)
	Reclassification (to) from nonaccretable difference		1,061			837
	Balance at end of period	$	13,402		$	17,438

Allowance_for_Loan_Losses_Tabl

Allowance for Loan Losses (Tables)	3 Months Ended
	Mar. 31, 2015
Receivables [Abstract]
Summary of Activity in Allowance for Loan Losses, and Ending Balance of Loans, Net of Unearned Fees for Periods Indicated	The following tables summarize the activity in the allowance for loan losses, and ending balance of loans, net of unearned fees for the periods indicated.
		Allowance for Loan Losses – Year Ended March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance	$	3,086		$	9,227		$	15,676		$	1,797		$	9		$	719		$	4,226		$	1,434		$	411		$	36,585
	Charge-offs		(81	)		—			(341	)		(11	)		—			(268	)		(534	)		—			—			(1,235	)
	Recoveries		1			96			119			3			20			152			87			11			19			508
	(Benefit) provision		(241	)		1,128			(221	)		191			(23	)		41			197			(695	)		(180	)		197
	Ending balance	$	2,765		$	10,451		$	15,233		$	1,980		$	6		$	644		$	3,976		$	750		$	250		$	36,055
	Ending balance:
	Individ. evaluated for impairment	$	988		$	799		$	1,857		$	337		$	1		$	92		$	559		$	59			—		$	4,692
	Loans pooled for evaluation	$	1,709		$	8,464		$	12,932		$	1,643		$	5		$	552		$	2,205		$	505		$	250		$	28,265
	Loans acquired with deteriorated credit quality	$	69		$	1,188		$	443			—			—			—		$	1,212		$	186			—		$	3,098
		Loans, net of unearned fees – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans	$	282,383		$	1,364,480		$	345,210		$	32,486		$	32		$	32,999		$	177,540		$	40,105		$	45,648		$	2,320,883
	Individ. evaluated for impairment	$	7,786		$	44,523		$	6,290		$	1,359		$	14		$	338		$	1,967		$	2,655		$	94		$	65,026
	Loans pooled for evaluation	$	270,571		$	1,292,006		$	329,961		$	30,374		$	18		$	32,591		$	168,517		$	36,714		$	45,554		$	2,206,306
	Loans acquired with deteriorated credit quality	$	4,026		$	27,951		$	8,959		$	753			—		$	70		$	7,056		$	736			—		$	49,551
		Allowance for Loan Losses – Year Ended December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance	$	3,154		$	9,700		$	16,375		$	1,208		$	66		$	589		$	4,331		$	1,559		$	1,263		$	38,245
	Charge-offs		(171	)		(110	)		(1,094	)		(29	)		(3	)		(599	)		(479	)		(4	)		(69	)		(2,558	)
	Recoveries		2			540			960			34			86			495			1,268			1,377			181			4,943
	(Benefit) provision		101			(903	)		(565	)		584			(140	)		234			(894	)		(1,498	)		(964	)		(4,045	)
	Ending balance	$	3,086		$	9,227		$	15,676		$	1,797		$	9		$	719		$	4,226		$	1,434		$	411		$	36,585
	Ending balance:
	Individ. evaluated for impairment	$	974		$	410		$	1,974		$	284			—		$	142		$	423		$	60			—		$	4,267
	Loans pooled for evaluation	$	1,915		$	8,408		$	13,251		$	1,513		$	9		$	572		$	2,569		$	332		$	322		$	28,891
	Loans acquired with deteriorated credit quality	$	197		$	409		$	451			—			—		$	5		$	1,234		$	1,042		$	89		$	3,427
		Loans, net of unearned fees – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans	$	279,420		$	1,335,939		$	352,584		$	31,314		$	112		$	33,074		$	174,945		$	38,618		$	35,518		$	2,282,524
	Individ. evaluated for impairment	$	7,188		$	41,932		$	6,968		$	1,278		$	18		$	323		$	1,757		$	2,683		$	99		$	62,246
	Loans pooled for evaluation	$	268,227		$	1,263,090		$	336,595		$	29,266		$	94		$	32,677		$	165,753		$	35,260		$	36,419		$	2,167,381
	Loans acquired with deteriorated credit quality	$	4,005		$	30,917		$	9,021		$	770			—		$	74		$	7,435		$	675			—		$	52,897
		Allowance for Loan Losses – Three Months Ended March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Beginning balance	$	3,154		$	9,700		$	16,375		$	1,208		$	66		$	589		$	4,331		$	1,559		$	1,263		$	38,245
	Charge-offs		(135	)		(13	)		(178	)		—			—			(127	)		(239	)		(4	)		(69	)		(765	)
	Recoveries		—			172			329			2			12			183			873			511			115			2,197
	(Benefit) provision		(39	)		16			(160	)		81			(33	)		(55	)		(829	)		(565	)		229			(1,355	)
	Ending balance	$	2,980		$	9,875		$	16,366		$	1,291		$	45		$	590		$	4,136		$	1,501		$	1,538		$	38,322
	Ending balance:
	Individ. evaluated for impairment	$	666		$	968		$	1,394		$	178		$	1		$	4		$	626		$	104			—		$	3,941
	Loans pooled for evaluation	$	1,962		$	8,129		$	14,489		$	1,113		$	44		$	586		$	2,194		$	769		$	1,033		$	30,319
	Loans acquired with deteriorated credit quality	$	352		$	778		$	484			—			—			—		$	1,316		$	627		$	505		$	4,062
		Loans, net of unearned fees – As of March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Ending balance:
	Total loans	$	195,826		$	930,472		$	337,802		$	15,776		$	575		$	27,633		$	119,418		$	37,394		$	22,156		$	1,687,052
	Individ. evaluated for impairment	$	7,322		$	59,613		$	7,091		$	774		$	49		$	101		$	2,537		$	2,793		$	19		$	80,299
	Loans pooled for evaluation	$	184,002		$	840,642		$	320,846		$	14,522		$	526		$	27,457		$	110,602		$	33,153		$	22,081		$	1,553,831
	Loans acquired with deteriorated credit quality	$	4,502		$	30,217		$	9,865		$	480			—		$	75		$	6,279		$	1,448		$	56		$	52,922
Presentation of Credit Quality Indicators	The following tables present ending loan balances by loan category and risk grade for the periods indicated:
		Credit Quality Indicators – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Originated loans:
	Pass	$	152,273		$	926,236		$	286,624		$	24,010			—		$	28,010		$	132,590		$	20,498		$	31,877		$	1,602,118
	Special mention		1,315			11,795			3,641			891		$	6			487			757			793			584			20,269
	Substandard		6,453			32,402			9,033			1,991			26			243			708			2,373			97			53,326
	Loss		—			—			—			—			—			—			—			—			—			—
	Total originated	$	160,041		$	970,433		$	299,298		$	26,892		$	32		$	28,740		$	134,055		$	23,664		$	32,558		$	1,675,713
	PNCI loans:
	Pass	$	116,888		$	348,541		$	34,903		$	4,662			—		$	3,914		$	36,128		$	15,705		$	13,090		$	573,831
	Special mention		680			12,874			935			105			—			123			5			—			—			14,722
	Substandard		748			4,681			1,115			74			—			152			296			—			—			7,066
	Loss		—			—			—			—			—			—			—			—			—			—
	Total PNCI	$	118,316		$	366,096		$	36,953		$	4,841			—		$	4,189		$	36,429		$	15,705		$	13,090		$	595,619
	PCI loans	$	4,026		$	27,951		$	8,959		$	753			—		$	70		$	7,056		$	736			—		$	49,551
	Total loans	$	282,383			1,364,480		$	345,210		$	32,486		$	32		$	32,999		$	177,540		$	40,105		$	45,648		$	2,320,883
		Credit Quality Indicators – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Originated loans:
	Pass	$	146,949		$	883,102		$	292,244		$	20,976		$	66		$	27,396		$	124,707		$	18,112		$	24,436		$	1,537,988
	Special mention		1,122			11,521			3,590			743			11			591			636			622			—			18,836
	Substandard		6,523			34,174			9,332			1,840			35			243			1,268			2,401			109			55,925
	Loss		—			—			—			—			—			—			—			—			—			—
	Total originated	$	154,594		$	928,797		$	305,166		$	23,559		$	112		$	28,230		$	126,611		$	21,135		$	24,545		$	1,612,749
	PNCI loans:
	Pass	$	119,643		$	359,537		$	36,531		$	6,813			—		$	4,399		$	40,628		$	16,808		$	11,973		$	596,332
	Special mention		547			12,979			936			147			—			230			268			—			—			15,107
	Substandard		631			3,709			930			25			—			141			3			—			—			5,439
	Loss		—			—			—			—			—			—			—			—			—			—
	Total PNCI	$	120,821		$	376,225		$	38,397		$	6,985			—		$	4,770		$	40,899		$	16,808		$	11,973		$	616,878
	PCI loans	$	4,005		$	30,917		$	9,021		$	770			—		$	74		$	7,435		$	675			—		$	52,897
	Total loans	$	279,420		$	1,335,939		$	352,584		$	31,314		$	112		$	33,074		$	174,945		$	38,618		$	36,518		$	2,282,524
Analysis of Past Due and Nonaccrual Loans	The following table shows the ending balance of current, past due, and nonaccrual originated loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual Originated Loans – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Originated loan balance:
	Past due:
	30-59 Days	$	1,225		$	545		$	1,689		$	140		$	2		$	5		$	318			—			—		$	3,924
	60-89 Days		—			714			285			276			—			5			35			—			—			1,315
	> 90 Days		629			1,028			565			390			14			59			24			—			—			2,709
	Total past due	$	1,854		$	2,287		$	2,539		$	806		$	16		$	69		$	377			—			—		$	7,948
	Current		158,187			968,146			296,759			26,086			16			28,671			133,678			23,664			32,558			1,667,765
	Total orig. loans	$	160,041		$	970,433		$	299,298		$	26,892		$	32		$	28,740		$	134,055		$	23,664		$	32,558		$	1,675,713
	> 90 Days and still accruing	$	328			—			—			—			—			—			—			—			—		$	328
	Nonaccrual loans	$	4,111		$	22,486		$	3,700		$	1,217		$	14		$	62		$	191		$	2,373		$	94		$	34,248
	The following table shows the ending balance of current, past due, and nonaccrual PNCI loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual PNCI Loans – As of March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	PNCI loan balance:
	Past due:
	30-59 Days	$	1,401		$	560		$	69			—			—		$	28			—			—			—		$	2,058
	60-89 Days		—			75			395			43			—			1			—			—			—			514
	> 90 Days		121			—			38			25			—			31			—			—			—			215
	Total past due	$	1,522		$	635		$	502		$	68			—		$	60			—			—			—		$	2,787
	Current		116,832			365,461			36,220			4,966			—			4,129			36,429			15,705			13,090			592,832
	Total PNCI loans	$	118,354		$	366,096		$	36,722		$	5,034			—		$	4,189		$	36,429		$	15,705		$	13,090		$	595,619
	> 90 Days and still accruing		—			—			—			—			—			—			—			—			—			—
	Nonaccrual loans	$	728		$	1,003		$	414		$	25			—		$	66			—			—			—		$	2,236
	The following table shows the ending balance of current, past due, and nonaccrual originated loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual Originated Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Originated loan balance:
	Past due:
	30-59 Days	$	1,296		$	735		$	2,066		$	615		$	4		$	64		$	739			—			—		$	5,519
	60-89 Days		919			—			296			192			—			24			99			—			—			1,530
	> 90 Days		100			900			754			202			17			46			61			—			—			2,080
	Total past due	$	2,315		$	1,635		$	3,116		$	1,009		$	21		$	134		$	899			—			—		$	9,129
	Current		152,279			927,162			302,050			22,550			91			28,096			125,712			21,135			24,545			1,603,620
	Total orig. loans	$	154,594		$	928,797		$	305,166		$	23,559		$	112		$	28,230		$	126,611		$	21,135		$	24,545		$	1,612,749
	> 90 Days and still accruing		—			—			—			—			—			—			—			—			—			—
	Nonaccrual loans	$	3,430		$	20,736		$	4,336		$	1,197		$	18		$	66		$	246		$	2,401		$	99		$	32,529
	The following table shows the ending balance of current, past due, and nonaccrual PNCI loans by loan category as of the date indicated:
		Analysis of Past Due and Nonaccrual PNCI Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	PNCI loan balance:
	Past due:
	30-59 Days	$	2,041		$	260		$	275			—			—		$	25		$	67			—			—		$	2,668
	60-89 Days		24			—			118			—			—			3			—			—			—			145
	> 90 Days		239			—			73			25			—			76			—			—			—			413
	Total past due	$	2,304		$	260		$	466		$	25			—		$	104		$	67			—			—		$	3,226
	Current		118,517			375,965			37,931			6,960			—			4,666			40,832			16,808			11,973		$	613,652
	Total PNCI loans	$	120,821		$	376,225		$	38,397		$	6,985			—		$	4,770		$	40,899		$	16,808		$	11,973		$	616,878
	> 90 Days and still accruing		—			—			—			—			—			—			—			—			—			—
	Nonaccrual loans	$	799		$	366		$	346		$	25			—		$	110			—			—			—		$	1,646
Impaired Loans	Impaired originated loans are those where management has concluded that it is probable that the borrower will be unable to pay all amounts due under the contractual terms. The following tables show the recorded investment (financial statement balance), unpaid principal balance, average recorded investment, and interest income recognized for impaired Originated and PNCI loans, segregated by those with no related allowance recorded and those with an allowance recorded for the periods indicated.
		Impaired Originated Loans – As of, or for the Three Months Ended, March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	With no related allowance recorded:
	Recorded investment	$	3,360		$	40,094		$	2,631		$	870		$	10		$	19		$	748		$	2,373		$	94		$	50,199
	Unpaid principal	$	5,330		$	43,898		$	5,791		$	1,335		$	30		$	23		$	776		$	6,585		$	186		$	63,954
	Average recorded Investment	$	3,323		$	39,286		$	2,816		$	810		$	12		$	22		$	580		$	2,387		$	96		$	49,332
	Interest income Recognized	$	8		$	283			—			—			—			—		$	11			—			—		$	302
	With an allowance recorded:
	Recorded investment	$	3,402		$	3,281		$	2,808		$	464		$	4		$	43		$	1,214		$	282			—		$	11,498
	Unpaid principal	$	3,570		$	3,432		$	3,077		$	566		$	6		$	53		$	1,316		$	282			—		$	12,302
	Related allowance	$	915		$	598		$	1,636		$	337		$	1		$	17		$	559		$	59			—		$	4,122
	Average recorded Investment	$	3,063		$	3,112		$	2,997		$	484		$	4		$	42		$	1,276		$	282			—		$	11,260
	Interest income Recognized	$	22		$	40		$	12		$	1			—			—		$	15		$	4			—		$	94
		Impaired PNCI Loans – As of, or for the Three Months Ended, March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	With no related allowance recorded:
	Recorded investment	$	389		$	313		$	414		$	25			—		$	59		$	5			—			—		$	1,205
	Unpaid principal	$	488		$	2,601		$	450		$	25			—		$	78		$	5			—			—		$	3,647
	Average recorded Investment	$	366		$	339		$	380		$	25			—		$	48		$	6			—			—		$	1,164
	Interest income Recognized	$	1			—			—			—			—			—			—			—			—		$	1
	With an allowance recorded:
	Recorded investment	$	635		$	835		$	437			—			—		$	217			—			—			—		$	2,124
	Unpaid principal	$	644		$	838		$	437			—			—		$	217			—			—			—		$	2,136
	Related allowance	$	73		$	201		$	221			—			—		$	75			—			—			—		$	570
	Average recorded Investment	$	734		$	490		$	436			—			—		$	219			—			—			—		$	1,879
	Interest income Recognized	$	2		$	10		$	4			—			—		$	2			—			—			—		$	18
		Impaired Originated Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	With no related allowance recorded:
	Recorded investment	$	3,287		$	38,477		$	3,001		$	750		$	14		$	25		$	412		$	2,401		$	99		$	48,466
	Unpaid principal	$	5,138		$	41,949		$	6,094		$	1,187		$	49		$	32		$	433		$	6,588		$	190		$	61,660
	Average recorded Investment	$	3,826		$	45,915		$	3,355		$	651		$	35		$	21		$	1,030		$	2,437		$	84		$	57,354
	Interest income Recognized	$	38		$	995		$	26		$	6			—		$	1		$	26			—		$	3		$	1,095
	With an allowance recorded:
	Recorded investment	$	2,724		$	2,943		$	3,185		$	504		$	4		$	41		$	1,338		$	282			—		$	11,021
	Unpaid principal	$	2,865		$	3,101		$	3,533		$	597		$	6		$	41		$	1,438		$	282			—		$	11,863
	Related allowance	$	797		$	302		$	1,769		$	284			—		$	11		$	423		$	60			—		$	3,646
	Average recorded Investment	$	2,677		$	4,119		$	2,982		$	365		$	4		$	25		$	1,428		$	283		$	55		$	11,938
	Interest income Recognized	$	91		$	144		$	71		$	13			—			—		$	71		$	19			—		$	409
		Impaired PNCI Loans – As of December 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	With no related allowance recorded:
	Recorded investment	$	343		$	366		$	346		$	25			—		$	37		$	7			—			—		$	1,124
	Unpaid principal	$	353		$	2,620		$	374		$	25			—		$	54		$	7			—			—		$	3,433
	Average recorded Investment	$	246		$	753		$	287		$	12			—		$	36		$	10			—			—		$	1,344
	Interest income Recognized	$	14			—		$	(1	)		—			—			—		$	1			—			—		$	14
	With an allowance recorded:
	Recorded investment	$	834		$	146		$	436			—			—		$	220			—			—			—		$	1,636
	Unpaid principal	$	852		$	146		$	436			—			—		$	220			—			—			—		$	1,654
	Related allowance	$	177		$	108		$	205			—			—		$	131			—			—			—		$	621
	Average recorded Investment	$	516		$	148		$	319			—			—		$	124			—			—			—		$	1,107
	Interest income Recognized	$	8		$	8		$	20			—			—		$	12			—			—			—		$	48
		Impaired Originated Loans – As of, or for the Three Months Ended, March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	With no related allowance recorded:
	Recorded investment	$	4,349		$	53,996		$	3,386		$	541		$	45		$	32		$	1,105		$	87		$	19		$	63,560
	Unpaid principal	$	6,532		$	59,159		$	6,833		$	921		$	82		$	37		$	1,120		$	225		$	101		$	75,010
	Average recorded Investment	$	4,206		$	57,403		$	3,972		$	483		$	66		$	21		$	1,370		$	1,415		$	39		$	68,975
Interest income Recognized	$	14		$	340		$	2			—			—			—		$	15			—			—		$	371
With an allowance recorded:
Recorded investment	$	2,457		$	4,599		$	3,214		$	234		$	4		$	5		$	1,421		$	2,707			—		$	14,641
Unpaid principal	$	2,528		$	5,240		$	3,449		$	300		$	5		$	6		$	1,509		$	6,773			—		$	19,810
Related allowance	$	502		$	855		$	1,228		$	178		$	1		$	1		$	626		$	104			—		$	3,495
Average recorded Investment	$	2,353		$	5,773		$	3,057		$	170		$	7		$	7		$	1,766		$	1,497		$	151		$	14,781
Interest income Recognized	$	13		$	25		$	14		$	1			—			—		$	13		$	5			—		$	71
	Impaired PNCI Loans – As of, or for the Three Months Ended, March 31, 2014
	RE Mortgage						Home Equity						Auto			Other						Construction
(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
With no related allowance recorded:
Recorded investment	$	84		$	870		$	326			—			—		$	34		$	11			—			—		$	1,325
Unpaid principal	$	84		$	3,044		$	336			—			—		$	45		$	11			—			—		$	3,520
Average recorded Investment	$	58		$	905		$	339			—			—		$	37		$	9			—			—		$	1,348
Interest income Recognized	$	2			—		$	6			—			—			—			—			—			—		$	8
With an allowance recorded:
Recorded investment	$	432		$	148		$	166			—			—		$	28			—			—			—		$	774
Unpaid principal	$	443		$	149		$	172			—			—		$	28			—			—			—		$	792
Related allowance	$	164		$	113		$	166			—			—		$	3			—			—			—		$	446
Average recorded Investment	$	334		$	157		$	195			—			—		$	28			—			—			—		$	714
Interest income Recognized	$	2		$	2			—			—			—			—			—			—			—		$	4
Troubled Debt Restructurings	The following tables show certain information regarding Troubled Debt Restructurings (TDRs) that occurred during the periods indicated:
		TDR Information for the Three Months Ended March 31, 2015
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Number		1			1			—			—			—			2			1			—			—			5
	Pre-mod outstanding principal balance	$	108		$	124			—			—			—		$	89		$	287			—			—		$	608
	Post-mod outstanding principal balance	$	110		$	124			—			—			—		$	89		$	288			—			—		$	611
	Financial impact due to TDR taken as additional provision	$	8		$	(5	)		—			—			—		$	5		$	164			—			—		$	172
	Number that defaulted during the period		—			—			1			—			—			—			—			—			—			1
	Recorded investment of TDRs that defaulted during the period		—			—		$	47			—			—			—			—			—			—		$	47
	the default of previous
	TDR taken as charge-offs or additional provisions		—			—			—			—			—			—			—			—			—			—
	The following tables show certain information regarding TDRs that occurred during the periods indicated:
		TDR Information for the Three Months Ended March 31, 2014
		RE Mortgage						Home Equity						Auto			Other						Construction
	(in thousands)	Resid.			Comm.			Lines			Loans			Indirect			Consum.			C&I			Resid.			Comm.			Total
	Number		2			2			2			—			—			—			1			1			1			9
	Pre-mod outstanding principal balance	$	695		$	256		$	279			—			—			—		$	38		$	102		$	118		$	1,488
	Post-mod outstanding principal balance	$	695		$	259		$	279			—			—			—		$	38		$	85		$	100		$	1,456
	Financial impact due to TDR taken as additional provision	$	37		$	9			—			—			—			—		$	18			—			—		$	64
	Number that defaulted during the period		—			1			—			—			—			—			1			—			—			2
	Recorded investment of TDRs that defaulted during the period		—		$	260			—			—			—			—		$	116			—			—		$	376
	Financial impact due to the default of previous
	TDR taken as charge-offs or additional provisions		—			—			—			—			—			—		$	(8	)		—			—		$	(8	)

Foreclosed_Assets_Tables

Foreclosed Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary of Activity in Balance of Foreclosed Assets	A summary of the activity in the balance of foreclosed assets follows (in thousands):
		Three months ended March 31, 2015								Three months ended March 31, 2014
		Noncovered			Covered		Total			Noncovered			Covered			Total
	Beginning balance, net	$	4,449		$	445	$	4,894		$	5,588		$	674		$	6,262
	Additions/transfers from loans		1,560			—		1,560			1,175			—			1,175
	Dispositions/sales		(495	)		—		(495	)		(4,186	)		—			(4,186	)
	Valuation adjustments		(67	)		—		(67	)		(26	)		(10	)		(36	)
	Ending balance, net	$	5,447		$	445	$	5,892		$	2,551		$	664		$	3,215
	Ending valuation allowance	$	263			—	$	263		$	111		$	10		$	121
	Ending number of foreclosed assets		29			1		30			22			4			26
	Proceeds from sale of foreclosed assets	$	806			—	$	806		$	5,413			—		$	5,413
	Gain on sale of foreclosed assets	$	311			—	$	311		$	1,227			—			1,227

Premises_and_Equipment_Tables

Premises and Equipment (Tables)	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Summary of Premises and Equipment	Premises and equipment were comprised of:
		March 31,			December 31,
		2015			2014
		(In thousands)
	Land & land improvements	$	8,883		$	8,933
	Buildings		38,939			39,638
	Furniture and equipment		28,160			28,446
			75,982			77,017
	Less: Accumulated depreciation		(33,152	)		(33,570	)
			42,830			43,447
	Construction in progress		16			46
	Total premises and equipment	$	42,846		$	43,493

Cash_Value_of_Life_Insurance_T

Cash Value of Life Insurance (Tables)	3 Months Ended
	Mar. 31, 2015
Investments, All Other Investments [Abstract]
Summary of Activity in Balance of Cash Value of Life Insurance	A summary of the activity in the balance of cash value of life insurance follows (in thousands):
		Three months ended March 31,
		2015		2014
	Beginning balance	$	92,337	$	52,309
	Increase in cash value of life insurance		675		397
	Ending balance	$	93,012	$	52,706
	End of period death benefit	$	165,847	$	94,999
	Number of policies owned		189		133
	Insurance companies used		14		6
	Current and former employees and directors covered		60		36

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Goodwill Intangible	The following table summarizes the Company’s goodwill intangible as of the dates indicated:
	(Dollar in Thousands)	March 31,			Additions		Reductions			December 31,
		2015								2014
	Goodwill	$	63,462			—		—		$	63,462
Summary of Core Deposit Intangibles	The following table summarizes the Company’s core deposit intangibles as of the dates indicated:
	(Dollar in Thousands)	March 31,			Additions		Reductions/			Fully		December 31,
		2015					Amortization			Depreciated		2014
	Core deposit intangibles	$	8,074			—		—			—	$	8,074
	Accumulated amortization		(1,312	)		—	$	(289	)		—		(1,023	)
	Core deposit intangibles, net	$	6,762			—	$	(289	)		—	$	7,051
Estimated Core Deposit Intangible Amortization	The following table summarizes the Company’s estimated core deposit intangible amortization (dollars in thousands):
	Years Ended	Estimated Core Deposit
		Intangible Amortization
	2015	$	1,157
	2016		1,157
	2017		1,109
	2018		1,044
	2019		948
	Thereafter	$	1,636

Mortgage_Servicing_Rights_Tabl

Mortgage Servicing Rights (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Fair Value of Mortgage Servicing Rights	The following tables summarize the activity in, and the main assumptions we used to determine the fair value of mortgage servicing rights (“MSRs”) for the periods indicated (dollars in thousands):
		Three months ended March 31,
		2015			2014
	Balance at beginning of period	$	7,378		$	6,165
	Additions		185			123
	Change in fair value		(506	)		(181	)
	Balance at end of period	$	7,057		$	6,107
	Contractually specified servicing fees, late fees and ancillary fees earned	$	534		$	420
	Balance of loans serviced at:
	Beginning of period	$	840,288		$	680,197
	End of period	$	832,143		$	672,341
	Weighted-average prepayment speed (CPR)		13	%		10.6	%
	Weighted-average discount rate		10	%		10	%

Indemnification_Asset_Tables

Indemnification Asset (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary of Activity in Balance of Indemnification Asset (Liability)	A summary of the activity in the balance of indemnification asset follows (in thousands):
		Three months ended March 31,
		2015			2014
	Beginning balance	$	(349	)	$	206
	Effect of actual and estimated future covered losses and recoveries		(62	)		(468	)
	Reimbursable (revenue) expenses incurred		(3	)		59
	Payments (received from) made to FDIC		(19	)		(17	)
	Ending balance	$	(433	)	$	(220	)
	Amount of indemnification asset (liability) recorded in other assets	$	114		$	(220	)
	Amount of indemnification asset (liability) recorded in other liabilities	$	(547	)		—
	Ending balance	$	(433	)	$	(220	)

Other_Assets_Tables

Other Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Summary of Other Assets	Other assets were comprised of (in thousands):
		March 31,		December 31,
		2015		2014
	Deferred tax asset, net	$	36,994	$	37,706
	Prepaid expense		3,268		2,034
	Software		1,198		1,327
	Advanced compensation		825		908
	Capital Trusts		1,691		1,690
	Miscellaneous other assets		7,026		8,070
	Total other assets	$	51,002	$	51,735

Deposits_Tables

Deposits (Tables)	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
Summary of Balances of Deposits	A summary of the balances of deposits follows (in thousands):
		March 31		December 31,
		2015		2014
	Noninterest-bearing demand	$	1,034,012	$	1,083,900
	Interest-bearing demand		795,471		782,385
	Savings		1,172,257		1,156,126
	Time certificates, $250,000 and over		37,181		38,217
	Other time certificates		310,567		319,795
	Total deposits	$	3,349,488	$	3,380,423

Reserve_for_Unfunded_Commitmen1

Reserve for Unfunded Commitments (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary of Activity in Reserve for Unfunded Commitments	The following tables summarize the activity in reserve for unfunded commitments for the periods indicated (dollars in thousands):
		Three months ended March 31,
		2015			2014
	Balance at beginning of period	$	2,145		$	2,415
	Provision for losses – Unfunded commitments		(130	)		(185	)
	Balance at end of period	$	2,015		$	2,230

Other_Liabilities_Tables

Other Liabilities (Tables)	3 Months Ended
	Mar. 31, 2015
Other Liabilities Disclosure [Abstract]
Components of Other Liabilities	Other liabilities were comprised of (in thousands):
		March 31,		December 31,
		2015		2014
	Deferred compensation	$	7,484	$	7,408
	Pension liability		27,074		26,798
	Joint beneficiary agreements		2,785		2,728
	Miscellaneous other liabilities		15,913		12,258
	Total other liabilities	$	53,256	$	49,192

Other_Borrowings_Tables

Other Borrowings (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary of Balances of Other Borrowings	A summary of the balances of other borrowings follows:
		March 31,		December 31,
		2015		2014
		(in thousands)
	Other collateralized borrowings, fixed rate, as of March 31, 2015 of 0.05%, payable on April 1, 2015	$	9,096	$	9,276
	Total other borrowings	$	9,096	$	9,276

Junior_Subordinated_Debt_Table

Junior Subordinated Debt (Tables)	3 Months Ended
	Mar. 31, 2015
Text Block [Abstract]
Summary of Terms and Recorded Balance of Subordinated Debenture	The following table summarizes the terms and recorded balance of each subordinated debenture as of the date indicated (dollars in thousands):
						Coupon Rate			As of March 31, 2015
						(Variable)
	Subordinated Debt Series	Maturity		Face		3 mo. LIBOR +			Current			Recorded
		Date		Value					Coupon Rate			Book Value
	TriCo Cap Trust I		10/7/33	$	20,619		3.05	%		3.3	%	$	20,619
	TriCo Cap Trust II		7/23/34		20,619		2.55	%		2.81	%		20,619
	North Valley Trust II		4/24/33		6,186		3.25	%		3.5	%		5,025
	North Valley Trust III		4/24/34		5,155		2.8	%		3.06	%		3,936
	North Valley Trust IV		3/15/36		10,310		1.33	%		1.6	%		6,121
				$	62,889							$	56,320

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Commitments under Non-Cancelable Operating Leases with Initial or Remaining Terms of One Year or More	At December 31, 2014, future minimum commitments under non-cancelable operating leases with initial or remaining terms of one year or more are as follows:
		Operating
		Leases
		(in thousands)
	2015	$	3,419
	2016		2,510
	2017		1,856
	2018		1,323
	2019		859
	Thereafter		1,180
	Future minimum lease payments	$	11,147
Summary of Bank's Commitments and Contingent Liabilities	The following table presents a summary of the Bank’s commitments and contingent liabilities:
	(in thousands)	March 31,		December 31,
		2015		2014
	Financial instruments whose amounts represent risk:
	Commitments to extend credit:
	Commercial loans	$	195,295	$	177,557
	Consumer loans		392,005		392,705
	Real estate mortgage loans		40,014		36,139
	Real estate construction loans		40,935		49,774
	Standby letters of credit		16,307		17,531
	Deposit account overdraft privilege	$	99,002	$	101,060

Stock_Options_and_Other_Equity1

Stock Options and Other Equity-Based Incentive Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option Activity	Stock option activity during the three months ended March 31, 2015 is summarized in the following table:
		Number				Option Price							Weighted		Weighted
		of Shares				per Share							Average		Average Fair
													Exercise		Value on
													Price		Date of Grant
	Outstanding at December 31, 2014		1,102,850			$	12.63			to	$	25.91	$	18.25
	Options granted		—				—			to		—		—		—
	Options exercised		(47,000	)		$	15.34			to	$	19.46	$	18.86
	Options forfeited		—				—			to		—		—
	Outstanding at March 31, 2015		1,055,850			$	12.63			to	$	25.91	$	18.22
Summary of Options Outstanding	The following table shows the number, weighted-average exercise price, intrinsic value, and weighted average remaining contractual life of options exercisable, options not yet exercisable and total options outstanding as of March 31, 2015:
		Currently				Currently Not			Total
		Exercisable				Exercisable			Outstanding
	Number of options		772,850				283,000			1,055,850
	Weighted average exercise price	$	18.6			$	17.2		$	18.22
	Intrinsic value (in thousands)	$	4,334			$	1,962		$	6,296
	Weighted average remaining contractual term (yrs.)		4.4				7.3			5.2
Restricted Stock Unit (RSU) Activity	Restricted stock unit (RSU) activity is summarized in the following table for the dates indicated:
		Service Condition Vesting RSUs						Market Plus Service Condition Vesting RSUs
		Number		Weighted				Number	Weighted
		of RSUs		Average Fair				of RSUs	Average Fair
				Value on					Value on
				Date of Grant					Date of Grant
	Outstanding at December 31, 2014	30,920						15,366
	RSUs granted	—			—			—		—
	RSUs added through dividend credits	141						—
	RSUs released	—						—
	RSUs forfeited/expired	—						—
	Outstanding at March 31, 2015	31,061						15,366

Noninterest_Income_and_Expense1

Noninterest Income and Expense (Tables)	3 Months Ended
	Mar. 31, 2015
Other Income and Expenses [Abstract]
Components of Other Noninterest Income	The components of other noninterest income were as follows (in thousands):
		Three months ended March 31,
		2015			2014
	Service charges on deposit accounts	$	3,600		$	2,690
	ATM and interchange fees		3,002			2,013
	Other service fees		714			520
	Mortgage banking service fees		534			420
	Change in value of mortgage servicing rights		(506	)		(181	)
	Total service charges and fees		7,344			5,462
	Gain on sale of loans		622			464
	Commissions on sale of non-deposit investment products		965			771
	Increase in cash value of life insurance		675			397
	Change in indemnification asset		(65	)		(412	)
	Gain on sale of foreclosed assets		311			1,227
	Sale of customer checks		128			101
	Lease brokerage income		137			107
	Loss on disposal of fixed assets		(84	)		(1	)
	Other		147			179
	Total other noninterest income		2,836			2,833
	Total noninterest income	$	10,180		$	8,295
Components of Noninterest Expense	The components of noninterest expense were as follows (in thousands):
		Three months ended March 31,
		2015			2014
	Base salaries, net of deferred loan origination costs	$	11,744		$	8,866
	Incentive compensation		1,596			1,123
	Benefits and other compensation costs		4,760			3,314
	Total salaries and benefits expense		18,100			13,303
	Occupancy		2,417			1,962
	Equipment		1,414			1,036
	Data processing and software		1,952			1,178
	ATM network charges		770			643
	Telecommunications		886			580
	Postage		312			227
	Courier service		248			234
	Advertising		808			342
	Assessments		651			521
	Operational losses		124			177
	Professional fees		1,119			614
	Foreclosed assets expense		98			158
	Provision for foreclosed asset losses		67			36
	Change in reserve for unfunded commitments		(130	)		(185	)
	Intangible amortization		289			52
	Merger expense		586			225
	Other		2,571			2,214
	Total other noninterest expense		14,182			10,014
	Total noninterest expense	$	32,282		$	23,317
	Merger expense:
	Data processing and software	$	108			—
	Professional fees		120		$	225
	Other		358			—
	Total merger expense	$	586		$	225

Income_Taxes_Tables

Income Taxes (Tables)	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Reconciliation of Effective Tax Rate and Statutory Federal Income Tax Rate	The effective tax rate and the statutory federal income tax rate are reconciled for the periods indicated as follows:
		Three months ended March 31,
		2015			2014
	Federal statutory income tax rate		35	%		35	%
	State income taxes, net of federal tax benefit		6.9			6.9
	Tax-exempt interest on municipal obligations		(0.4	)		(0.4	)
	Increase in cash value of insurance policies		(1.7	)		(1.1	)
	Other		0.8			0.2
	Effective Tax Rate		40.6	%		40.6	%

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
Earnings Per Share [Abstract]
Computation of Earnings Per Share	Earnings per share have been computed based on the following:
		Three months ended
		March 31,
	(In thousands)	2015		2014
	Net income	$	8,336	$	7,365
	Average number of common shares outstanding		22,727		16,097
	Effect of dilutive stock options and restricted stock		223		225
	Average number of common shares outstanding used to calculate diluted earnings per share		22,950		16,322
	Options excluded from diluted earnings per share because the effect of these options was antidilutive		23		101
	Restricted stock excluded from diluted earnings per share because the effect of these restricted stock was antidilutive		—		n/a

Comprehensive_Income_Tables

Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Components of Other Comprehensive Income and Related Tax Effects	The components of other comprehensive income and related tax effects are as follows:
		Three Months Ended
		March 31,
		2015			2014
	(in thousands)
	Unrealized holding gains (losses) on available for sale securities before reclassifications	$	15		$	(105	)
	Amounts reclassified out of accumulated other comprehensive income-		—			—
	Unrealized holding gains (losses) on available for sale securities after reclassifications		15			(105	)
	Tax effect		(6	)		45
	Unrealized holding gains (losses) on available for sale securities, net of tax		9			(60	)
	Change in unfunded status of the supplemental retirement plans before reclassifications		—			—
	Amounts reclassified out of accumulated other comprehensive income:
	Amortization of prior service cost		(14	)		5
	Amortization of actuarial losses		206			4
	Total amounts reclassified out of accumulated other comprehensive income		192			9
	Change in unfunded status of the supplemental retirement plans after reclassifications		192			9
	Tax effect		(81	)		(4	)
	Change in unfunded status of the supplemental retirement plans, net of tax		111			5
	Change in joint beneficiary agreement liability before reclassifications		—			—
	Amounts reclassified out of accumulated other comprehensive income		—			—
	Change in joint beneficiary agreement liability after reclassifications		—			—
	Tax effect		—			—
	Change in joint beneficiary agreement liability, net of tax		—			—
	Total other comprehensive gain (loss)	$	120		$	(55	)
Components of Accumulated Other Comprehensive Income	The components of accumulated other comprehensive income, included in shareholders’ equity, are as follows:
		March 31,			December 31,
		2015			2014
		(in thousands)
	Net unrealized gains on available for sale securities	$	4,055		$	4,040
	Tax effect		(1,705	)		(1,699	)
	Unrealized holding gains on available for sale securities, net of tax		2,350			2,341
	Unfunded status of the supplemental retirement plans		(7,693	)		(7,885	)
	Tax effect		3,234			3,315
	Unfunded status of the supplemental retirement plans, net of tax		(4,459	)		(4,570	)
	Joint beneficiary agreement liability		26			26
	Tax effect		—			—
	Joint beneficiary agreement liability, net of tax		26			26
	Accumulated other comprehensive loss	$	(2,083	)	$	(2,203	)

Retirement_Plans_Tables

Retirement Plans (Tables)	3 Months Ended
	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Net Periodic Benefit Cost Recognized for Supplemental Retirement Plans	The following table sets forth the net periodic benefit cost recognized for the plans:
		Three months ended March 31,
		2015			2014
		(In thousands)
	Net pension cost included the following components:
	Service cost-benefits earned during the period	$	256		$	163
	Interest cost on projected benefit obligation		239			174
	Amortization of net obligation at transition		—			—
	Amortization of prior service cost		(14	)		35
	Recognized net actuarial loss		206			4
	Net periodic pension cost	$	687		$	376

Related_Party_Transactions_Tab

Related Party Transactions (Tables)	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Summary of Loan Activity	The following table summarizes the activity in these loans for 2015 and 2014 (in thousands):
	Balance December 31, 2013	$	2,636
	Advances/new loans		2,106
	Removed/payments		(1,610	)
	Balance December 31, 2014	$	3,132
	Advances/new loans		235
	Removed/payments		(416	)
	Balance March 31, 2015	$	2,951

Fair_Value_Measurement_Tables

Fair Value Measurement (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Recorded Amount of Assets and Liabilities Measured at Fair Value on Recurring Basis	The table below presents the recorded amount of assets and liabilities measured at fair value on a recurring basis (in thousands):
		Total			Level 1			Level 2			Level 3
	Fair value at March 31, 2015
	Securities available for sale:
	Obligations of U.S. government corporations and agencies	$	210,535			—		$	210,535			—
	Obligations of states and political subdivisions		9,656			—			9,656			—
	Corporate debt securities		1,905			—			1,905			—
	Marketable equity services		3,030		$	3,030			—			—
	Mortgage servicing rights		7,057			—			—		$	7,057
	Total assets measured at fair value	$	232,183		$	3,030		$	222,096		$	7,057
		Total			Level 1			Level 2			Level 3
	Fair value at December 31, 2014
	Securities available for sale:
	Obligations of U.S. government corporations and agencies	$	75,120			—		$	75,120			—
	Obligations of states and political subdivisions		3,175			—			3,175			—
	Corporate debt securities		1,908			—			1,908			—
	Marketable equity securities		3,002		$	3,002			—			—
	Mortgage servicing rights		7,378			—			—		$	7,378
	Total assets measured at fair value	$	90,583		$	3,002		$	80,203		$	7,378
Reconciliation of Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) on Recurring Basis	The following table provides a reconciliation of assets and liabilities measured at fair value using significant unobservable inputs (Level 3) on a recurring basis during the time periods indicated. Had there been any transfer into or out of Level 3 during the time periods indicated, the amount included in the “Transfers into (out of) Level 3” column would represent the beginning balance of an item in the period (interim quarter) during which it was transferred (in thousands):
		Beginning			Transfers			Change			Issuances			Ending
		Balance			into (out of)			Included						Balance
					Level 3			in Earnings
	Three months ended March 31,
	2015: Mortgage servicing rights	$	7,378			—		$	(506	)	$	185		$	7,057
	2014: Mortgage servicing rights	$	6,165			—		$	(181	)	$	123		$	6,107
Quantitative Information about Recurring Level 3 Fair Value Measurements	The following table presents quantitative information about recurring Level 3 fair value measurements at March 31, 2015:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Mortgage Servicing Rights	$	7,057		Discounted cash flow		Constant prepayment rate	6.0%-23.1%, 13.0%
							Discount rate	10.0%-12.0%, 10.0%
	The following table presents quantitative information about recurring Level 3 fair value measurements at December 31, 2014:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Mortgage Servicing Rights	$	7,378		Discounted cash flow		Constant prepayment rate	5.7%-23.4%, 12.0%
							Discount rate	10.0%-12.0%, 10.0%
Assets and Liabilities Measured at Fair Value on Nonrecurring Basis	The tables below present the recorded amount of assets and liabilities measured at fair value on a nonrecurring basis, as of the dates indicated, that had a write-down or an additional allowance provided during the periods indicated (in thousands):
		Total			Level 1			Level 2			Level 3			Total
														(Losses)
	Three months ended March 31, 2015
	Fair value:
	Impaired Originated & PNCI loans	$	3,690			—			—		$	3,690		$	(181	)
	Foreclosed assets		2,384			—			—			2,384			(64	)
	Total assets measured at fair value	$	6,074			—			—		$	6,074		$	(245	)
		Total			Level 1			Level 2			Level 3			Total
														(Losses)
	Year ended December 31, 2014
	Fair value:
	Impaired Originated & PNCI loans	$	2,480			—			—		$	2,480		$	(636	)
	Foreclosed assets		2,611			—			—			2,611			(137	)
	Total assets measured at fair value	$	5,091			—			—		$	5,091		$	(773	)
		Total			Level 1			Level 2			Level 3			Total
														(Losses)
	Three months ended March 31, 2014
	Fair value:
	Impaired Originated & PNCI loans	$	21,498			—			—		$	21,498		$	(272	)
	Foreclosed assets		802			—			—			802			(21	)
	Total assets measured at fair value	$	22,300			—			—		$	22,300		$	(293	)
Quantitative Information about Level 3 Fair Value Measurements for Financial Instruments Measured at Fair Value on Nonrecurring Basis	The following table presents quantitative information about Level 3 fair value measurements for financial instruments measured at fair value on a nonrecurring basis at March 31, 2015:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Impaired Originated & PNCI loans	$	3,690		Sales comparison		Adjustment for differences	(5.0)%-(41.0)%, (8.8)%
					approach		between comparable sales	8.0%-9.1%, 8.1%
					Income approach		Capitalization rate
	Foreclosed assets	$	2,384		Sales comparison		Adjustment for differences	(5.0)%-(30.1)%, (9.3)%
					approach		between comparable sales
	The following table presents quantitative information about Level 3 fair value measurements for financial instruments measured at fair value on a nonrecurring basis at December 31, 2014:
		Fair Value			Valuation		Unobservable	Range,
		(in thousands)			Technique		Inputs	Weighted Average
	Impaired Originated & PNCI loans	$	2,480		Sales comparison		Adjustment for differences	(5.0)%-(42.5)%, (10.1)%
					approach		between comparable sales	9.09%-9.09%, 9.09%
					Income approach		Capitalization rate
	Foreclosed assets	$	2,611		Sales comparison		Adjustment for differences	(5.0)%-(29.4)%, (8.2)%
					approach		between comparable sales
Estimated Fair Values of Financial Instruments that are Reported at Amortized Cost in Consolidated Balance Sheets	The estimated fair values of financial instruments that are reported at amortized cost in the Corporation’s consolidated balance sheets, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value, were as follows (in thousands):
		March 31, 2015						December 31, 2014
		Carrying			Fair			Carrying			Fair
		Amount			Value			Amount			Value
	Financial assets:
	Level 1 inputs:
	Cash and due from banks	$	84,682		$	84,682		$	93,150		$	93,150
	Cash at Federal Reserve and other banks		196,546			196,546			517,578			517,578
	Level 2 inputs:
	Securities held to maturity		802,482			817,793			676,426			688,779
	Restricted equity securities		16,956			N/A			16,956			N/A
	Loans held for sale		5,413			5,413			3,579			3,579
	Level 3 inputs:
	Loans, net		2,284,828			2,379,343			2,245,938			2,342,570
	Indemnification (liability) asset		(433	)		(433	)		(349	)		(349	)
	Financial liabilities:
	Level 2 inputs:
	Deposits		3,349,488			3,349,507			3,380,423			3,380,486
	Other borrowings		9,096			9,096			9,276			9,276
	Level 3 inputs:
	Junior subordinated debt		56,320			46,424			56,272			45,053
		Contract			Fair			Contract			Fair
		Amount			Value			Amount			Value
	Off-balance sheet:
	Level 3 inputs:
	Commitments	$	668,249		$	6,682		$	656,175		$	6,562
	Standby letters of credit		16,307			163			17,531			175
	Overdraft privilege commitments		99,002			990			101,060			1,011

TriCo_Bancshares_Condensed_Fin1

TriCo Bancshares Condensed Financial Statements (Parent Only) (Tables)	3 Months Ended
	Mar. 31, 2015
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Balance Sheets	Condensed Balance Sheets
		March 31,			December 31,
		2015			2014
		(In thousands)
	Assets
	Cash and Cash equivalents	$	2,044		$	2,229
	Investment in Tri Counties Bank		477,845			470,797
	Other assets		1,738			1,902
	Total assets	$	481,627		$	474,928
	Liabilities and shareholders’ equity
	Other liabilities	$	474		$	484
	Junior subordinated debt		56,320			56,272
	Total liabilities		56,794			56,756
	Shareholders’ equity:
	Common stock, no par value: authorized 50,000,000 shares; issued and outstanding 22,740,503 and 22,714,964 shares, respectively		245,316			244,318
	Retained earnings		181,600			176,057
	Accumulated other comprehensive loss, net		(2,083	)		(2,203	)
	Total shareholders’ equity		424,833			418,172
	Total liabilities and shareholders’ equity	$	481,627		$	474,928
Condensed Statements of Income	Condensed Statements of Income
		Three months ended March 31,
		2015			2014
		(In thousands)
	Interest expense	$	482		$	304
	Administration expense		153			324
	Loss before equity in net income of Tri Counties Bank		(635	)		(628	)
	Equity in net income of Tri Counties Bank:
	Distributed		2,120			2,050
	Under distributed		6,584			5,679
	Income tax benefit		267			264
	Net income	$	8,336		$	7,365
Condensed Statements of Comprehensive Income	Condensed Statements of Comprehensive Income
		Three months ended March 31,
		2015			2014
		(In thousands)
	Net income	$	8,336		$	7,365
	Other comprehensive loss, net of tax:
	Increase (decrease) in unrealized gains on available for sale securities arising during the period		9			(60	)
	Change in minimum pension liability		111			5
	Other comprehensive loss		120			(55	)
	Comprehensive income	$	8,456		$	7,310
Condensed Statements of Cash Flows	Condensed Statements of Cash Flows
		Three months ended March 31,
		2015			2014
		(In thousands)
	Operating activities:
	Net income	$	8,336		$	7,365
	Adjustments to reconcile net income to net cash provided by operating activities:
	Under distributed equity in earnings of Tri Counties Bank		(6,584	)		(5,679	)
	Equity compensation vesting expense		324			296
	Stock option excess tax benefits		(18	)		(184	)
	Net change in other assets and liabilities		(124	)		(360	)
	Net cash provided by operating activities		1,934			1,438
	Investing activities: None
	Financing activities:
	Stock option excess tax benefits		18			184
	Issuance of common stock through option exercise		405			306
	Repurchase of common stock		(27	)		(293	)
	Cash dividends paid — common		(2,515	)		(1,772	)
	Net cash used for financing activities		(2,119	)		(1,575	)
	Net change in cash and cash equivalents		(185	)		(137	)
	Cash and cash equivalents at beginning of year		2,229			2,520
	Cash and cash equivalents at end of year	$	2,044		$	2,383

Regulatory_Matters_Tables

Regulatory Matters (Tables)	3 Months Ended
	Mar. 31, 2015
Banking and Thrift [Abstract]
Actual and Required Capital Ratios of Bank	The following table presents actual and required capital ratios as of March 31, 2015 for the Company and the Bank under Basel III Capital Rules. The minimum capital amounts presented include the minimum required capital levels as of March 31, 2015 based on the phased-in provisions of the Basel III Capital Rules and the minimum required capital levels as of January 1, 2019 when the Basel III Capital Rules have been fully phased-in. Capital levels required to be considered well capitalized are based upon prompt corrective action regulations, as amended to reflect the changes under the Basel III Capital Rules.
		Actual					Minimum Capital					Minimum Capital					Required to be
							Required – Basel III					Required – Basel III					Considered Well
							Phase-in Schedule					Fully Phased In					Capitalized
		Amount		Ratio			Amount		Ratio			Amount		Ratio			Amount		Ratio
		(dollars in thousands)
	As of March 31, 2015:
	Total Capital
	(to Risk Weighted Assets):
	Consolidated	$	444,192		15.23	%	$	233,279		8	%	$	306,178		10.5	%	$	291,598		10	%
	Tri Counties Bank	$	442,590		15.19	%	$	233,138		8	%	$	305,993		10.5	%	$	291,422		10	%
	Tier 1 Capital
	(to Risk Weighted Assets):
	Consolidated	$	407,722		13.98	%	$	174,959		6	%	$	247,858		8.5	%	$	233,279		8	%
	Tri Counties Bank	$	406,142		13.94	%	$	174,853		6	%	$	247,709		8.5	%	$	233,138		8	%
	Common equity Tier 1 Capital
	(to Risk Weighted Assets):
	Consolidated	$	353,131		12.11	%	$	131,219		4.5	%	$	204,119		7	%	$	189,539		6.5	%
	Tri Counties Bank	$	406,142		13.94	%	$	131,140		4.5	%	$	203,996		7	%	$	189,424		6.5	%
	Tier 1 Capital (to Average Assets):
	Consolidated	$	407,722		10.68	%	$	152,748		4	%	$	152,748		4	%	$	190,935		5	%
	Tri Counties Bank	$	406,142		10.64	%	$	152,676		4	%	$	152,676		4	%	$	190,845		5	%
	The following table presents actual and required capital ratios as of December 31, 2014 for the Company and the Bank under the regulatory capital rules then in effect.
		Actual					Minimum					Minimum
							Capital Requirement					To Be Well
												Capitalized Under
												Prompt Corrective
												Action Provisions
		Amount		Ratio			Amount		Ratio			Amount		Ratio
		(dollars in thousands)
	As of December 31, 2014:
	Total Capital (to Risk Weighted Assets):
	Consolidated	$	436,955		15.63	%	$	223,603		8	%		N/A		N/A
	Tri Counties Bank	$	433,286		15.51	%	$	223,449		8	%	$	279,311		10	%
	Tier 1 Capital (to Risk Weighted Assets):
	Consolidated	$	401,971		14.38	%	$	111,801		4	%		N/A		N/A
	Tri Counties Bank	$	398,325		14.26	%	$	111,724		4	%	$	167,587		6	%
	Tier 1 Capital (to Average Assets):
	Consolidated	$	401,971		10.8	%	$	148,819		4	%		N/A		N/A
	Tri Counties Bank	$	398,325		10.71	%	$	148,734		4	%	$	185,918		5	%

Summary_of_Quarterly_Results_o1

Summary of Quarterly Results of Operations (unaudited) (Tables)	3 Months Ended
	Mar. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Results of Operations	The following table sets forth the results of operations for the periods indicated, and is unaudited; however, in the opinion of Management, it reflects all adjustments (which include only normal recurring adjustments) necessary to present fairly the summarized results for such periods.
		2015 Quarters Ended
		December 31,			September 30,			June 30,		March 31,
		(dollars in thousands, except per share data)
	Interest and dividend income:
	Loans:
	Discount accretion PCI – cash basis									$	172
	Discount accretion PCI – other										1,274
	Discount accretion PNCI										1,348
	All other loan interest income										28,371
	Total loan interest income										31,165
	Debt securities, dividends and interest bearing cash at Banks (not FTE)										6,560
	Total interest income										37,725
	Interest expense										1,382
	Net interest income										36,343
	(Benefit from) provision for loan losses										197
	Net interest income after provision for loan losses										36,146
	Noninterest income										10,180
	Noninterest expense										32,282
	Income before income taxes										14,044
	Income tax expense										5,708
	Net income									$	8,336
	Per common share:
	Net income (diluted)									$	0.36
	Dividends									$	0.11
		2014 Quarters Ended
		December 31,			September 30,			June 30,		March 31,
		(dollars in thousands, except per share data)
	Interest and dividend income:
	Loans:
	Discount accretion PCI – cash basis	$	107		$	290		$	69	$	203
	Discount accretion PCI – other		919			822			811		984
	Discount accretion PNCI		796			402			624		379
	All other loan interest income		28,914			23,466			22,929		22,172
	Total loan interest income		30,736			24,980			24,433		23,738
	Debt securities, dividends and interest bearing cash at Banks (not FTE)		5,671			4,151			3,985		3,421
	Total interest income		36,407			29,131			28,418		27,159
	Interest expense		1,437			1,082			1,075		1,087
	Net interest income		34,970			28,049			27,343		26,072
	(Benefit from) provision for loan losses		(1,421	)		(2,977	)		1,708		(1,355	)
	Net interest income after provision for loan losses		36,391			31,026			25,635		27,427
	Noninterest income		9,755			8,589			7,877		8,295
	Noninterest expense		36,566			25,380			25,116		23,317
	Income before income taxes		9,580			14,235			8,396		12,405
	Income tax expense		3,930			6,001			3,537		5,040
	Net income	$	5,650		$	8,234		$	4,859	$	7,365
	Per common share:
	Net income (diluted)	$	0.25		$	0.5		$	0.3	$	0.45
	Dividends	$	0.11		$	0.11		$	0.11	$	0.11

Summary_of_Significant_Account2

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014
	Trust
	Segment
Significant Of Accounting Policies [Line Items]
Number of subsidiary business trusts	5
Company's investments in the trusts	$1,691,000
Number of business segment	1
Trading securities	0	0
Recognized OTTI losses	0	0
Loans contractual past due	90 days
TDR loans payment period in nonaccrual status	6 months
Reserve for unimpaired loans			$1,438,000
Tri Counties Bank [Member]
Significant Of Accounting Policies [Line Items]
Number of traditional operating branches	57
Number of in-store operating branches	16
California [Member]
Significant Of Accounting Policies [Line Items]
Number of counties	26
Furniture and equipment [Member] | Minimum [Member]
Significant Of Accounting Policies [Line Items]
Estimated useful lives of the related assets or lease terms	3 years
Furniture and equipment [Member] | Maximum [Member]
Significant Of Accounting Policies [Line Items]
Estimated useful lives of the related assets or lease terms	10 years
Land improvements and buildings [Member] | Minimum [Member]
Significant Of Accounting Policies [Line Items]
Estimated useful lives of the related assets or lease terms	15 years
Land improvements and buildings [Member] | Maximum [Member]
Significant Of Accounting Policies [Line Items]
Estimated useful lives of the related assets or lease terms	40 years

Business_Combinations_Addition

Business Combinations - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	6 Months Ended
	Oct. 03, 2014	Mar. 31, 2015	Jun. 30, 2014	Dec. 31, 2014	Aug. 21, 2007
			Bank
Business Acquisition [Line Items]
Business acquisition, common stock issued to acquiree's shareholders	6,575,550
Fixed share exchange ratio	0.9433
Aggregate ownership percentage	28.90%
Cash in-lieu of fractional shares	$6,823
Business combination share outstanding		22,740,503		22,714,964	15,814,662
Assets		3,895,860,000		3,916,458,000
North Valley Bancorp [Member]
Business Acquisition [Line Items]
Acquisition, completion date		3-Oct-14
Closing stock price	$23.01
Consideration paid per share	$21.71
Cash in-lieu of fractional shares	7,000
Business combination share outstanding	22,714,964
Business combination consideration value	151,310,000
Number of commercial banks			22
Assets			935,000,000
Increase in net book value of land and buildings acquired	4,785,000
Recognized intangible related to acquisition	6,614,000
North Valley Bancorp [Member] | Junior subordinated debt [Member]
Business Acquisition [Line Items]
Discount on debt instrument	6,664,000
North Valley Bancorp [Member] | Minimum [Member] | Junior subordinated debt [Member]
Business Acquisition [Line Items]
Amortization period of debt discount	18 years
North Valley Bancorp [Member] | Maximum [Member] | Junior subordinated debt [Member]
Business Acquisition [Line Items]
Amortization period of debt discount	21 years
North Valley Bancorp [Member] | Core deposit intangibles [Member]
Business Acquisition [Line Items]
Recognized intangible related to acquisition	$6,614,000
Percentage of acquired intangibles	0.97%
Finite lived intangible asset useful life	7 years

Business_Combinations_Schedule

Business Combinations - Schedule of Fair Value of Consideration Transferred, Identifiable Net Assets Acquired and Resulting Goodwill (Detail) (USD $)	0 Months Ended
	Oct. 03, 2014	Mar. 31, 2015	Dec. 31, 2014
Fair value of consideration transferred:
Cash consideration	$6,823
Liabilities assumed:
Goodwill recognized		63,462,000	63,462,000
North Valley Bancorp [Member]
Fair value of consideration transferred:
Fair value of shares issued	151,303,000
Cash consideration	7,000
Total fair value of consideration transferred	151,310,000
Asset acquired:
Cash and cash equivalents	141,412,000
Securities available for sale	17,288,000
Securities held to maturity	189,950,000
Restricted equity securities	5,378,000
Loans	499,327,000
Foreclosed assets	695,000
Premises and equipment	11,936,000
Cash value of life insurance	38,075,000
Core deposit intangible	6,614,000
Other assets	20,064,000
Total assets acquired	930,739,000
Liabilities assumed:
Deposits	801,956,000
Other liabilities	10,429,000
Junior subordinated debt	14,987,000
Total liabilities assumed	827,372,000
Total net assets acquired	103,367,000
Goodwill recognized	$47,943,000

Business_Combinations_Summary_

Business Combinations - Summary of Estimated Fair Value Adjustments Resulting In Goodwill (Detail) (USD $)	0 Months Ended
	Oct. 03, 2014	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Cash payments to North Valley Bancorp Shareholders	$6,823
Goodwill		63,462,000	63,462,000
North Valley Bancorp [Member]
Business Acquisition [Line Items]
Value of stock consideration paid to North Valley Bancorp Shareholders	151,303,000
Cash payments to North Valley Bancorp Shareholders	7,000
Cost basis net assets acquired	-98,040,000
Goodwill	47,943,000
North Valley Bancorp [Member] | Deferred income taxes [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	6,293,000
North Valley Bancorp [Member] | Loans [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	5,832,000
North Valley Bancorp [Member] | Premises and equipment [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	-4,785,000
North Valley Bancorp [Member] | Core deposit intangibles [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	-6,283,000
North Valley Bancorp [Member] | Junior subordinated debt [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	-6,664,000
North Valley Bancorp [Member] | Other [Member]
Business Acquisition [Line Items]
Fair Value Adjustments	$280,000

Business_Combinations_Schedule1

Business Combinations - Schedule of Cost Basis, Fair Value Discount and loan Acquired (Detail) (North Valley Bancorp [Member], USD $)	Oct. 03, 2014
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Cost Basis	$514,125
Discount	-14,798
Fair Value	499,327
PNCI [Member]
Business Acquisition [Line Items]
Cost Basis	502,637
Discount	-12,721
Fair Value	489,916
PCI - Other [Member]
Business Acquisition [Line Items]
Cost Basis	11,488
Discount	-2,077
Fair Value	$9,411

Business_Combinations_Summary_1

Business Combinations - Summary of Principal Balance Loans Acquired (Detail) (North Valley Bancorp [Member], USD $)	Oct. 03, 2014
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Undiscounted contractual cash flows	$734,437
Undiscounted cash flows not expected to be collected (nonaccretable difference)	-6,295
Undiscounted cash flows expected to be collected	728,142
Accretable yield at acquisition	-228,815
Estimated fair value of loans acquired at acquisition	499,327
Purchase discount	14,798
Cost Basis	514,125
PNCI [Member]
Business Acquisition [Line Items]
Undiscounted contractual cash flows	718,731
Undiscounted cash flows expected to be collected	718,731
Accretable yield at acquisition	-228,815
Estimated fair value of loans acquired at acquisition	489,916
Purchase discount	12,721
Cost Basis	502,637
PCI - Other [Member]
Business Acquisition [Line Items]
Undiscounted contractual cash flows	15,706
Undiscounted cash flows not expected to be collected (nonaccretable difference)	-6,295
Undiscounted cash flows expected to be collected	9,411
Estimated fair value of loans acquired at acquisition	9,411
Purchase discount	2,077
Cost Basis	$11,488

Investment_Securities_Amortize

Investment Securities - Amortized Cost and Estimated Fair Values of Investments in Debt and Equity Securities (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$221,071	$79,165
Gross Unrealized Gains	4,297	4,065
Gross Unrealized Losses	-242	-25
Estimated Fair Value	225,126	83,205
Amortized Cost, Held to Maturity	802,482	676,426
Gross Unrealized Gains, Held to Maturity	15,821	13,185
Gross Unrealized Losses, Held to Maturity	-510	-832
Estimated Fair Value, Held to Maturity	817,793	688,779
Obligations of U.S. government corporations and agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	206,476	71,144
Gross Unrealized Gains	4,221	4,001
Gross Unrealized Losses	-162	-25
Estimated Fair Value	210,535	75,120
Amortized Cost, Held to Maturity	786,889	660,836
Gross Unrealized Gains, Held to Maturity	15,726	13,055
Gross Unrealized Losses, Held to Maturity	-339	-677
Estimated Fair Value, Held to Maturity	802,276	673,214
Obligations of states and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	9,700	3,130
Gross Unrealized Gains	36	45
Gross Unrealized Losses	-80
Estimated Fair Value	9,656	3,175
Amortized Cost, Held to Maturity	15,593	15,590
Gross Unrealized Gains, Held to Maturity	95	130
Gross Unrealized Losses, Held to Maturity	-171	-155
Estimated Fair Value, Held to Maturity	15,517	15,565
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,895	1,891
Gross Unrealized Gains	10	17
Estimated Fair Value	1,905	1,908
Marketable equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,000	3,000
Gross Unrealized Gains	30	2
Estimated Fair Value	$3,030	$3,002

Investment_Securities_Addition

Investment Securities - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Investment Securities [Line Items]
Investment securities sold	$0	$0
Investment securities carrying value	153,121,000		143,992,000
Mortgage-backed securities	$993,365,000
Life of mortgage-backed securities	5 years 2 months 12 days
Obligations of U.S. government corporations and agencies [Member]
Investment Securities [Line Items]
Debt securities	14
Percentage of aggregate depreciation in unrealized losses	-0.21%
Obligations of states and political subdivisions [Member]
Investment Securities [Line Items]
Debt securities	13
Percentage of aggregate depreciation in unrealized losses	-2.48%
Corporate debt securities [Member]
Investment Securities [Line Items]
Debt securities	0
Marketable equity securities [Member]
Investment Securities [Line Items]
Debt securities	0

Investment_Securities_Amortize1

Investment Securities - Amortized Cost and Estimated Fair Value of Debt Securities by Contractual Maturity (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investments, Debt and Equity Securities [Abstract]
Due in one year, Amortized Cost	$1,896
Due after one year through five years, Amortized Cost	4,014
Due after five years through ten years, Amortized Cost	31,848
Due after ten years, Amortized Cost	183,313
Totals, Amortized Cost	221,071
Due in one year, Estimated Fair Value	1,906
Due after one year through five years, Estimated Fair Value	4,202
Due after five years through ten years, Estimated Fair Value	33,332
Due after ten years, Estimated Fair Value	185,686
Totals, Estimated Fair Value	225,126
Due in one year, Amortized Cost, Held to Maturity	0
Due after one year through five years, Amortized Cost, Held to Maturity	0
Due after five years through ten years, Amortized Cost, Held to Maturity	1,125
Due after ten years, Amortized Cost, Held to Maturity	801,357
Totals, Amortized Cost, Held to Maturity	802,482	676,426
Due in one year, Estimated Fair Value, Held to Maturity	0
Due after one year through five years, Estimated Fair Value, Held to Maturity	0
Due after five years through ten years, Estimated Fair Value, Held to Maturity	1,134
Due after ten years, Estimated Fair Value, Held to Maturity	816,659
Estimated Fair Value, Held to Maturity	$817,793	$688,779

Investment_Securities_Gross_Un

Investment Securities - Gross Unrealized Losses on Investment (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	$84,568	$6,774
Less than 12 months, Unrealized Loss	-242	-25
12 months or more, Fair Value	0	0
12 months or more, Unrealized Loss	0	0
Total Fair Value	84,568	6,774
Total Unrealized Loss	-242	-25
Less than 12 months, Fair Value, held to maturity	164,968	1,935
Less than 12 months, Unrealized Loss, held to maturity	-366	-27
12 months or more, Fair Value, held to maturity	1,075	58,146
12 months or more, Unrealized Loss, held to maturity	-144	-805
Total Fair Value, held to maturity	166,043	60,081
Total Unrealized Loss, held to maturity	-510	-832
Obligations of U.S. government corporations and agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	78,146	6,774
Less than 12 months, Unrealized Loss	-162	-25
12 months or more, Fair Value	0	0
12 months or more, Unrealized Loss	0	0
Total Fair Value	78,146	6,774
Total Unrealized Loss	-162	-25
Less than 12 months, Fair Value, held to maturity	162,549	335
Less than 12 months, Unrealized Loss, held to maturity	-339	-1
12 months or more, Fair Value, held to maturity		56,288
12 months or more, Unrealized Loss, held to maturity		-676
Total Fair Value, held to maturity	162,549	56,623
Total Unrealized Loss, held to maturity	-339	-677
Obligations of states and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	6,422
Less than 12 months, Unrealized Loss	-80
12 months or more, Fair Value	0	0
12 months or more, Unrealized Loss	0	0
Total Fair Value	6,422
Total Unrealized Loss	-80
Less than 12 months, Fair Value, held to maturity	2,419	1,600
Less than 12 months, Unrealized Loss, held to maturity	-27	-26
12 months or more, Fair Value, held to maturity	1,075	1,858
12 months or more, Unrealized Loss, held to maturity	-144	-129
Total Fair Value, held to maturity	3,494	3,458
Total Unrealized Loss, held to maturity	-171	-155
Corporate debt securities [Member]
Schedule of Available-for-sale Securities [Line Items]
12 months or more, Fair Value	0	0
12 months or more, Unrealized Loss	0	0
Marketable equity securities [Member]
Schedule of Available-for-sale Securities [Line Items]
12 months or more, Fair Value	0	0
12 months or more, Unrealized Loss	$0	$0

Loans_Summary_of_Loan_Balances

Loans - Summary of Loan Balances (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Mortgage loans on real estate:
Total mortgage loan on real estate	$1,646,863	$1,615,359
Consumer:
Total consumer loans	410,727	417,084
Commercial	177,540	174,945
Construction:
Total construction	85,753	75,136
Total loans, net of deferred loan fees and discounts	2,320,883	2,282,524
Total principal balance of loans owed, net of charge-offs	2,359,282	2,322,853
Unamortized net deferred loan fees	-4,810	-4,793
Discounts to principal balance of loans owed, net of charge-offs	-33,589	-35,536
Total loans, net of unamortized deferred loan fees and discounts	2,320,883	2,282,524
Noncovered loans	2,300,463	2,260,256
Covered loans	20,420	22,268
Total loans, net of unamortized deferred loan fees and discounts	2,320,883	2,282,524
Allowance for loan losses	-36,055	-36,585	-38,322	-38,245
Auto Indirect [Member]
Consumer:
Total consumer loans	32	112
Other [Member]
Consumer:
Total consumer loans	32,999	33,074
Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	282,383	279,420
Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	1,364,480	1,335,939
Construction:
Total construction	45,648	36,518
Home equity lines of credit [Member]
Consumer:
Total consumer loans	345,210	352,584
Construction:
Allowance for loan losses	-15,233	-15,676	-16,366	-16,375
Home equity loans [Member]
Consumer:
Total consumer loans	32,486	31,314
Residential [Member]
Construction:
Total construction	40,105	38,618
Originated [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	1,130,474	1,083,391
Consumer:
Total consumer loans	354,962	357,067
Commercial	134,055	126,611
Construction:
Total construction	56,222	45,680
Total loans, net of deferred loan fees and discounts	1,675,713	1,612,749
Total principal balance of loans owed, net of charge-offs	1,680,523	1,617,542
Unamortized net deferred loan fees	-4,810	-4,793
Total loans, net of unamortized deferred loan fees and discounts	1,675,713	1,612,749
Noncovered loans	1,675,713	1,612,749
Total loans, net of unamortized deferred loan fees and discounts	1,675,713	1,612,749
Allowance for loan losses	-30,032	-29,860
Originated [Member] | Auto Indirect [Member]
Consumer:
Total consumer loans	32	112
Originated [Member] | Other [Member]
Consumer:
Total consumer loans	28,740	28,230
Originated [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	160,041	154,594
Originated [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	970,433	928,797
Construction:
Total construction	32,558	24,545
Originated [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	299,298	305,166
Originated [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	26,892	23,559
Originated [Member] | Residential [Member]
Construction:
Total construction	23,664	21,135
PNCI [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	484,412	497,046
Consumer:
Total consumer loans	45,983	50,152
Commercial	36,429	40,899
Construction:
Total construction	28,795	28,781
Total loans, net of deferred loan fees and discounts	595,619	616,878
Total principal balance of loans owed, net of charge-offs	612,382	634,490
Discounts to principal balance of loans owed, net of charge-offs	-16,763	-17,612
Total loans, net of unamortized deferred loan fees and discounts	595,619	616,878
Noncovered loans	595,619	616,878
Total loans, net of unamortized deferred loan fees and discounts	595,619	616,878
Allowance for loan losses	-2,925	-3,296
PNCI [Member] | Other [Member]
Consumer:
Total consumer loans	4,189	4,770
PNCI [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	118,316	120,821
PNCI [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	366,096	376,225
Construction:
Total construction	13,090	11,973
PNCI [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	36,953	38,397
PNCI [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	4,841	6,985
PNCI [Member] | Residential [Member]
Construction:
Total construction	15,705	16,808
PCI - Cash basis [Member]
Consumer:
Total consumer loans	5,583	5,603
Commercial	6	8
Construction:
Total loans, net of deferred loan fees and discounts	5,589	5,611
Total principal balance of loans owed, net of charge-offs	14,592	14,805
Discounts to principal balance of loans owed, net of charge-offs	-9,003	-9,194
Total loans, net of unamortized deferred loan fees and discounts	5,589	5,611
Noncovered loans	5,589	5,611
Total loans, net of unamortized deferred loan fees and discounts	5,589	5,611
Allowance for loan losses	-340	-348
PCI - Cash basis [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	5,459	5,478
PCI - Cash basis [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	124	125
PCI - Other [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	31,977	34,922
Consumer:
Total consumer loans	4,199	4,262
Commercial	7,050	7,427
Construction:
Total construction	736	675
Total loans, net of deferred loan fees and discounts	43,962	47,286
Total principal balance of loans owed, net of charge-offs	51,785	56,016
Discounts to principal balance of loans owed, net of charge-offs	-7,823	-8,730
Total loans, net of unamortized deferred loan fees and discounts	43,962	47,286
Noncovered loans	23,542	25,018
Covered loans	20,420	22,268
Total loans, net of unamortized deferred loan fees and discounts	43,962	47,286
Allowance for loan losses	-2,758	-3,081
PCI - Other [Member] | Other [Member]
Consumer:
Total consumer loans	70	74
PCI - Other [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	4,026	4,005
PCI - Other [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	27,951	30,917
PCI - Other [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	3,500	3,543
PCI - Other [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	629	645
PCI - Other [Member] | Residential [Member]
Construction:
Total construction	$736	$675

Loans_Change_in_Accretable_Yie

Loans - Change in Accretable Yield for PCI (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Change in accretable yield:
Balance at beginning of period	$14,159	$18,232
Accretion to interest income	-1,818	-1,631
Reclassification (to) from nonaccretable difference	1,061	837
Balance at end of period	$13,402	$17,438

Allowance_for_Loan_Losses_Summ

Allowance for Loan Losses - Summary of Activity in Allowance for Loan Losses, and Ending Balance of Loans, Net of Unearned Fees for Periods Indicated (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$2,320,883	$1,687,052	$2,282,524
Individ. evaluated for impairment	65,026	80,299	62,246
Loans pooled for evaluation	2,206,306	1,553,831	2,167,381
Loans acquired with deteriorated credit quality	49,551	52,922	52,897
Beginning balance	36,585	38,245	38,245
Charge-offs	-1,235	-765	-2,558
Recoveries	508	2,197	4,943
(Benefit) provision	197	-1,355	-4,045
Ending balance	36,055	38,322	36,585
Ending balance:
Individ. evaluated for impairment	4,692	3,941	4,267
Loans pooled for evaluation	28,265	30,319	28,891
Loans acquired with deteriorated credit quality	3,098	4,062	3,427
Home equity lines of credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	345,210	337,802	352,584
Individ. evaluated for impairment	6,290	7,091	6,968
Loans pooled for evaluation	329,961	320,846	336,595
Loans acquired with deteriorated credit quality	8,959	9,865	9,021
Beginning balance	15,676	16,375	16,375
Charge-offs	-341	-178	-1,094
Recoveries	119	329	960
(Benefit) provision	-221	-160	-565
Ending balance	15,233	16,366	15,676
Ending balance:
Individ. evaluated for impairment	1,857	1,394	1,974
Loans pooled for evaluation	12,932	14,489	13,251
Loans acquired with deteriorated credit quality	443	484	451
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,999	27,633	33,074
Individ. evaluated for impairment	338	101	323
Loans pooled for evaluation	32,591	27,457	32,677
Loans acquired with deteriorated credit quality	70	75	74
Beginning balance	719	589	589
Charge-offs	-268	-127	-599
Recoveries	152	183	495
(Benefit) provision	41	-55	234
Ending balance	644	590	719
Ending balance:
Individ. evaluated for impairment	92	4	142
Loans pooled for evaluation	552	586	572
Loans acquired with deteriorated credit quality			5
Construction [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	40,105	37,394	38,618
Individ. evaluated for impairment	2,655	2,793	2,683
Loans pooled for evaluation	36,714	33,153	35,260
Loans acquired with deteriorated credit quality	736	1,448	675
Beginning balance	1,434	1,559	1,559
Charge-offs		-4	-4
Recoveries	11	511	1,377
(Benefit) provision	-695	-565	-1,498
Ending balance	750	1,501	1,434
Ending balance:
Individ. evaluated for impairment	59	104	60
Loans pooled for evaluation	505	769	332
Loans acquired with deteriorated credit quality	186	627	1,042
Construction [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	45,648	22,156	35,518
Individ. evaluated for impairment	94	19	99
Loans pooled for evaluation	45,554	22,081	36,419
Loans acquired with deteriorated credit quality		56
Beginning balance	411	1,263	1,263
Charge-offs		-69	-69
Recoveries	19	115	181
(Benefit) provision	-180	229	-964
Ending balance	250	1,538	411
Ending balance:
Loans pooled for evaluation	250	1,033	322
Loans acquired with deteriorated credit quality		505	89
RE Mortgage [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	282,383	195,826	279,420
Individ. evaluated for impairment	7,786	7,322	7,188
Loans pooled for evaluation	270,571	184,002	268,227
Loans acquired with deteriorated credit quality	4,026	4,502	4,005
Beginning balance	3,086	3,154	3,154
Charge-offs	-81	-135	-171
Recoveries	1		2
(Benefit) provision	-241	-39	101
Ending balance	2,765	2,980	3,086
Ending balance:
Individ. evaluated for impairment	988	666	974
Loans pooled for evaluation	1,709	1,962	1,915
Loans acquired with deteriorated credit quality	69	352	197
RE Mortgage [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,364,480	930,472	1,335,939
Individ. evaluated for impairment	44,523	59,613	41,932
Loans pooled for evaluation	1,292,006	840,642	1,263,090
Loans acquired with deteriorated credit quality	27,951	30,217	30,917
Beginning balance	9,227	9,700	9,700
Charge-offs		-13	-110
Recoveries	96	172	540
(Benefit) provision	1,128	16	-903
Ending balance	10,451	9,875	9,227
Ending balance:
Individ. evaluated for impairment	799	968	410
Loans pooled for evaluation	8,464	8,129	8,408
Loans acquired with deteriorated credit quality	1,188	778	409
Home equity loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,486	15,776	31,314
Individ. evaluated for impairment	1,359	774	1,278
Loans pooled for evaluation	30,374	14,522	29,266
Loans acquired with deteriorated credit quality	753	480	770
Beginning balance	1,797	1,208	1,208
Charge-offs	-11		-29
Recoveries	3	2	34
(Benefit) provision	191	81	584
Ending balance	1,980	1,291	1,797
Ending balance:
Individ. evaluated for impairment	337	178	284
Loans pooled for evaluation	1,643	1,113	1,513
Auto Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32	575	112
Individ. evaluated for impairment	14	49	18
Loans pooled for evaluation	18	526	94
Beginning balance	9	66	66
Charge-offs			-3
Recoveries	20	12	86
(Benefit) provision	-23	-33	-140
Ending balance	6	45	9
Ending balance:
Individ. evaluated for impairment	1	1
Loans pooled for evaluation	5	44	9
C&I [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	177,540	119,418	174,945
Individ. evaluated for impairment	1,967	2,537	1,757
Loans pooled for evaluation	168,517	110,602	165,753
Loans acquired with deteriorated credit quality	7,056	6,279	7,435
Beginning balance	4,226	4,331	4,331
Charge-offs	-534	-239	-479
Recoveries	87	873	1,268
(Benefit) provision	197	-829	-894
Ending balance	3,976	4,136	4,226
Ending balance:
Individ. evaluated for impairment	559	626	423
Loans pooled for evaluation	2,205	2,194	2,569
Loans acquired with deteriorated credit quality	$1,212	$1,316	$1,234

Allowance_for_Loan_Losses_Pres

Allowance for Loan Losses - Presentation of Credit Quality Indicators (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$2,320,883	$2,282,524	$1,687,052
Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,675,713	1,612,749
PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	595,619	616,878
PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	49,551	52,897
Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,602,118	1,537,988
Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	573,831	596,332
Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	20,269	18,836
Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	14,722	15,107
Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	53,326	55,925
Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	7,066	5,439
Residential [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	40,105	38,618	37,394
Residential [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	23,664	21,135
Residential [Member] | PNCI loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	15,705	16,808
Residential [Member] | PCI loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	736	675
Residential [Member] | Pass [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	20,498	18,112
Residential [Member] | Pass [Member] | PNCI loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	15,705	16,808
Residential [Member] | Special mention [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	793	622
Residential [Member] | Substandard [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	2,373	2,401
Commercial [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	45,648	35,518	22,156
Commercial [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,558	24,545
Commercial [Member] | PNCI loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,090	11,973
Commercial [Member] | Pass [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	31,877	24,436
Commercial [Member] | Pass [Member] | PNCI loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	13,090	11,973
Commercial [Member] | Special mention [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	584
Commercial [Member] | Substandard [Member] | Originated loans [Member] | Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	97	109
Home equity lines of credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	345,210	352,584	337,802
Home equity lines of credit [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	299,298	305,166
Home equity lines of credit [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	36,953	38,397
Home equity lines of credit [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	8,959	9,021
Home equity lines of credit [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	286,624	292,244
Home equity lines of credit [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	34,903	36,531
Home equity lines of credit [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,641	3,590
Home equity lines of credit [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	935	936
Home equity lines of credit [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	9,033	9,332
Home equity lines of credit [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,115	930
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,999	33,074	27,633
Other Consumer [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	28,740	28,230
Other Consumer [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,189	4,770
Other Consumer [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	70	74
Other Consumer [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	28,010	27,396
Other Consumer [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	3,914	4,399
Other Consumer [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	487	591
Other Consumer [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	123	230
Other Consumer [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	243	243
Other Consumer [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	152	141
RE Mortgage [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	282,383	279,420	195,826
RE Mortgage [Member] | Residential [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	160,041	154,594
RE Mortgage [Member] | Residential [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	118,316	120,821
RE Mortgage [Member] | Residential [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,026	4,005
RE Mortgage [Member] | Residential [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	152,273	146,949
RE Mortgage [Member] | Residential [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	116,888	119,643
RE Mortgage [Member] | Residential [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,315	1,122
RE Mortgage [Member] | Residential [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	680	547
RE Mortgage [Member] | Residential [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	6,453	6,523
RE Mortgage [Member] | Residential [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	748	631
RE Mortgage [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,364,480	1,335,939	930,472
RE Mortgage [Member] | Commercial [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	970,433	928,797
RE Mortgage [Member] | Commercial [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	366,096	376,225
RE Mortgage [Member] | Commercial [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	27,951	30,917
RE Mortgage [Member] | Commercial [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	926,236	883,102
RE Mortgage [Member] | Commercial [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	348,541	359,537
RE Mortgage [Member] | Commercial [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	11,795	11,521
RE Mortgage [Member] | Commercial [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	12,874	12,979
RE Mortgage [Member] | Commercial [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,402	34,174
RE Mortgage [Member] | Commercial [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,681	3,709
Home equity loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32,486	31,314	15,776
Home equity loans [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	26,892	23,559
Home equity loans [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,841	6,985
Home equity loans [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	753	770
Home equity loans [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	24,010	20,976
Home equity loans [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	4,662	6,813
Home equity loans [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	891	743
Home equity loans [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	105	147
Home equity loans [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	1,991	1,840
Home equity loans [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	74	25
Auto Indirect [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32	112	575
Auto Indirect [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	32	112
Auto Indirect [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans		66
Auto Indirect [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	6	11
Auto Indirect [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	26	35
C&I [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	177,540	174,945	119,418
C&I [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	134,055	126,611
C&I [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	36,429	40,899
C&I [Member] | PCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	7,056	7,435
C&I [Member] | Pass [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	132,590	124,707
C&I [Member] | Pass [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	36,128	40,628
C&I [Member] | Special mention [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	757	636
C&I [Member] | Special mention [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	5	268
C&I [Member] | Substandard [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	708	1,268
C&I [Member] | Substandard [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total loans	$296	$3

Allowance_for_Loan_Losses_Addi

Allowance for Loan Losses - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
	Category
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of categories occupied under commercial real estate loans	2
Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired TDRs Loans	45,641,000	$45,676,000	$56,179,000
Additional funds in TDRs	4,000	54,000	1,000
PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Impaired TDRs Loans	1,231,000	1,307,000	1,179,000
Obligations to lend additional funds on TDRs	0	$0	$0
Minimum [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Period of collateral payment of loan	3 months
Maximum [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Period of collateral payment of loan	12 months

Allowance_for_Loan_Losses_Anal

Allowance for Loan Losses - Analysis of Past Due and Nonaccrual Loans (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	$3,924	$5,519
60-89 Days	1,315	1,530
> 90 Days	2,709	2,080
Total past due	7,948	9,129
Current	1,667,765	1,603,620
Total orig. loans	1,675,713	1,612,749
> 90 Days and still accruing	328
Nonaccrual loans	34,248	32,529
PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	2,058	2,668
60-89 Days	514	145
> 90 Days	215	413
Total past due	2,787	3,226
Current	592,832	613,652
Total orig. loans	595,619	616,878
Nonaccrual loans	2,236	1,646
RE Mortgage [Member] | Residential [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	1,225	1,296
60-89 Days		919
> 90 Days	629	100
Total past due	1,854	2,315
Current	158,187	152,279
Total orig. loans	160,041	154,594
> 90 Days and still accruing	328
Nonaccrual loans	4,111	3,430
RE Mortgage [Member] | Residential [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	1,401	2,041
60-89 Days		24
> 90 Days	121	239
Total past due	1,522	2,304
Current	116,832	118,517
Total orig. loans	118,354	120,821
Nonaccrual loans	728	799
RE Mortgage [Member] | Commercial [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	545	735
60-89 Days	714
> 90 Days	1,028	900
Total past due	2,287	1,635
Current	968,146	927,162
Total orig. loans	970,433	928,797
Nonaccrual loans	22,486	20,736
RE Mortgage [Member] | Commercial [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	560	260
60-89 Days	75
Total past due	635	260
Current	365,461	375,965
Total orig. loans	366,096	376,225
Nonaccrual loans	1,003	366
Home equity lines of credit [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	1,689	2,066
60-89 Days	285	296
> 90 Days	565	754
Total past due	2,539	3,116
Current	296,759	302,050
Total orig. loans	299,298	305,166
Nonaccrual loans	3,700	4,336
Home equity lines of credit [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	69	275
60-89 Days	395	118
> 90 Days	38	73
Total past due	502	466
Current	36,220	37,931
Total orig. loans	36,722	38,397
Nonaccrual loans	414	346
Home equity loans [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	140	615
60-89 Days	276	192
> 90 Days	390	202
Total past due	806	1,009
Current	26,086	22,550
Total orig. loans	26,892	23,559
Nonaccrual loans	1,217	1,197
Home equity loans [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
60-89 Days	43
> 90 Days	25	25
Total past due	68	25
Current	4,966	6,960
Total orig. loans	5,034	6,985
Nonaccrual loans	25	25
Auto Indirect [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	2	4
> 90 Days	14	17
Total past due	16	21
Current	16	91
Total orig. loans	32	112
Nonaccrual loans	14	18
Other Consumer [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	5	64
60-89 Days	5	24
> 90 Days	59	46
Total past due	69	134
Current	28,671	28,096
Total orig. loans	28,740	28,230
Nonaccrual loans	62	66
Other Consumer [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	28	25
60-89 Days	1	3
> 90 Days	31	76
Total past due	60	104
Current	4,129	4,666
Total orig. loans	4,189	4,770
Nonaccrual loans	66	110
C&I [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days	318	739
60-89 Days	35	99
> 90 Days	24	61
Total past due	377	899
Current	133,678	125,712
Total orig. loans	134,055	126,611
Nonaccrual loans	191	246
C&I [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due: 30-59 Days		67
Total past due		67
Current	36,429	40,832
Total orig. loans	36,429	40,899
Construction [Member] | Residential [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	23,664	21,135
Total orig. loans	23,664	21,135
Nonaccrual loans	2,373	2,401
Construction [Member] | Residential [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	15,705	16,808
Total orig. loans	15,705	16,808
Construction [Member] | Commercial [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	32,558	24,545
Total orig. loans	32,558	24,545
Nonaccrual loans	94	99
Construction [Member] | Commercial [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	13,090	11,973
Total orig. loans	$13,090	$11,973

Allowance_for_Loan_Losses_Impa

Allowance for Loan Losses - Impaired Loans (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	$50,199	$63,560	$48,466
Unpaid principal, With no related allowance recorded	63,954	75,010	61,660
Average recorded Investment, With no related allowance recorded	49,332	68,975	57,354
Interest income Recognized, With no related allowance recorded	302	371	1,095
Recorded investment, With an allowance recorded	11,498	14,641	11,021
Unpaid principal, With an allowance recorded	12,302	19,810	11,863
Related allowance, With an allowance recorded	4,122	3,495	3,646
Average recorded Investment, With an allowance recorded	11,260	14,781	11,938
Interest income Recognized, With an allowance recorded	94	71	409
PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	1,205	1,325	1,124
Unpaid principal, With no related allowance recorded	3,647	3,520	3,433
Average recorded Investment, With no related allowance recorded	1,164	1,348	1,344
Interest income Recognized, With no related allowance recorded	1	8	14
Recorded investment, With an allowance recorded	2,124	774	1,636
Unpaid principal, With an allowance recorded	2,136	792	1,654
Related allowance, With an allowance recorded	570	446	621
Average recorded Investment, With an allowance recorded	1,879	714	1,107
Interest income Recognized, With an allowance recorded	18	4	48
RE Mortgage [Member] | Residential [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	3,360	4,349	3,287
Unpaid principal, With no related allowance recorded	5,330	6,532	5,138
Average recorded Investment, With no related allowance recorded	3,323	4,206	3,826
Interest income Recognized, With no related allowance recorded	8	14	38
Recorded investment, With an allowance recorded	3,402	2,457	2,724
Unpaid principal, With an allowance recorded	3,570	2,528	2,865
Related allowance, With an allowance recorded	915	502	797
Average recorded Investment, With an allowance recorded	3,063	2,353	2,677
Interest income Recognized, With an allowance recorded	22	13	91
RE Mortgage [Member] | Residential [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	389	84	343
Unpaid principal, With no related allowance recorded	488	84	353
Average recorded Investment, With no related allowance recorded	366	58	246
Interest income Recognized, With no related allowance recorded	1	2	14
Recorded investment, With an allowance recorded	635	432	834
Unpaid principal, With an allowance recorded	644	443	852
Related allowance, With an allowance recorded	73	164	177
Average recorded Investment, With an allowance recorded	734	334	516
Interest income Recognized, With an allowance recorded	2	2	8
RE Mortgage [Member] | Commercial [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	40,094	53,996	38,477
Unpaid principal, With no related allowance recorded	43,898	59,159	41,949
Average recorded Investment, With no related allowance recorded	39,286	57,403	45,915
Interest income Recognized, With no related allowance recorded	283	340	995
Recorded investment, With an allowance recorded	3,281	4,599	2,943
Unpaid principal, With an allowance recorded	3,432	5,240	3,101
Related allowance, With an allowance recorded	598	855	302
Average recorded Investment, With an allowance recorded	3,112	5,773	4,119
Interest income Recognized, With an allowance recorded	40	25	144
RE Mortgage [Member] | Commercial [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	313	870	366
Unpaid principal, With no related allowance recorded	2,601	3,044	2,620
Average recorded Investment, With no related allowance recorded	339	905	753
Recorded investment, With an allowance recorded	835	148	146
Unpaid principal, With an allowance recorded	838	149	146
Related allowance, With an allowance recorded	201	113	108
Average recorded Investment, With an allowance recorded	490	157	148
Interest income Recognized, With an allowance recorded	10	2	8
Home equity lines of credit [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	2,631	3,386	3,001
Unpaid principal, With no related allowance recorded	5,791	6,833	6,094
Average recorded Investment, With no related allowance recorded	2,816	3,972	3,355
Interest income Recognized, With no related allowance recorded		2	26
Recorded investment, With an allowance recorded	2,808	3,214	3,185
Unpaid principal, With an allowance recorded	3,077	3,449	3,533
Related allowance, With an allowance recorded	1,636	1,228	1,769
Average recorded Investment, With an allowance recorded	2,997	3,057	2,982
Interest income Recognized, With an allowance recorded	12	14	71
Home equity lines of credit [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	414	326	346
Unpaid principal, With no related allowance recorded	450	336	374
Average recorded Investment, With no related allowance recorded	380	339	287
Interest income Recognized, With no related allowance recorded		6	-1
Recorded investment, With an allowance recorded	437	166	436
Unpaid principal, With an allowance recorded	437	172	436
Related allowance, With an allowance recorded	221	166	205
Average recorded Investment, With an allowance recorded	436	195	319
Interest income Recognized, With an allowance recorded	4		20
Home equity loans [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	870	541	750
Unpaid principal, With no related allowance recorded	1,335	921	1,187
Average recorded Investment, With no related allowance recorded	810	483	651
Interest income Recognized, With no related allowance recorded			6
Recorded investment, With an allowance recorded	464	234	504
Unpaid principal, With an allowance recorded	566	300	597
Related allowance, With an allowance recorded	337	178	284
Average recorded Investment, With an allowance recorded	484	170	365
Interest income Recognized, With an allowance recorded	1	1	13
Home equity loans [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	25		25
Unpaid principal, With no related allowance recorded	25		25
Average recorded Investment, With no related allowance recorded	25		12
Auto Indirect [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	10	45	14
Unpaid principal, With no related allowance recorded	30	82	49
Average recorded Investment, With no related allowance recorded	12	66	35
Recorded investment, With an allowance recorded	4	4	4
Unpaid principal, With an allowance recorded	6	5	6
Related allowance, With an allowance recorded	1	1
Average recorded Investment, With an allowance recorded	4	7	4
Other Consumer [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	19	32	25
Unpaid principal, With no related allowance recorded	23	37	32
Average recorded Investment, With no related allowance recorded	22	21	21
Interest income Recognized, With no related allowance recorded			1
Recorded investment, With an allowance recorded	43	5	41
Unpaid principal, With an allowance recorded	53	6	41
Related allowance, With an allowance recorded	17	1	11
Average recorded Investment, With an allowance recorded	42	7	25
Other Consumer [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	59	34	37
Unpaid principal, With no related allowance recorded	78	45	54
Average recorded Investment, With no related allowance recorded	48	37	36
Recorded investment, With an allowance recorded	217	28	220
Unpaid principal, With an allowance recorded	217	28	220
Related allowance, With an allowance recorded	75	3	131
Average recorded Investment, With an allowance recorded	219	28	124
Interest income Recognized, With an allowance recorded	2		12
C&I [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	748	1,105	412
Unpaid principal, With no related allowance recorded	776	1,120	433
Average recorded Investment, With no related allowance recorded	580	1,370	1,030
Interest income Recognized, With no related allowance recorded	11	15	26
Recorded investment, With an allowance recorded	1,214	1,421	1,338
Unpaid principal, With an allowance recorded	1,316	1,509	1,438
Related allowance, With an allowance recorded	559	626	423
Average recorded Investment, With an allowance recorded	1,276	1,766	1,428
Interest income Recognized, With an allowance recorded	15	13	71
C&I [Member] | PNCI loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	5	11	7
Unpaid principal, With no related allowance recorded	5	11	7
Average recorded Investment, With no related allowance recorded	6	9	10
Interest income Recognized, With no related allowance recorded			1
Construction [Member] | Residential [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	2,373	87	2,401
Unpaid principal, With no related allowance recorded	6,585	225	6,588
Average recorded Investment, With no related allowance recorded	2,387	1,415	2,437
Recorded investment, With an allowance recorded	282	2,707	282
Unpaid principal, With an allowance recorded	282	6,773	282
Related allowance, With an allowance recorded	59	104	60
Average recorded Investment, With an allowance recorded	282	1,497	283
Interest income Recognized, With an allowance recorded	4	5	19
Construction [Member] | Commercial [Member] | Originated loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment, With no related allowance recorded	94	19	99
Unpaid principal, With no related allowance recorded	186	101	190
Average recorded Investment, With no related allowance recorded	96	39	84
Interest income Recognized, With no related allowance recorded			3
Average recorded Investment, With an allowance recorded		$151	$55

Allowance_for_Loan_Losses_Trou

Allowance for Loan Losses - Troubled Debt Restructurings (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
	SecurityLoan	SecurityLoan
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number	5	9
Pre-mod outstanding principal balance	$608	$1,488
Post-mod outstanding principal balance	611	1,456
Financial impact due to TDR taken as additional provision	172	64
Number that defaulted during the period	1	2
Recorded investment of TDRs that defaulted during the period	47	376
Financial impact due to the default of previous TDR taken as charge-offs or additional provisions		-8
Home equity lines of credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number		2
Pre-mod outstanding principal balance		279
Post-mod outstanding principal balance		279
Number that defaulted during the period	1
Recorded investment of TDRs that defaulted during the period	47
RE Mortgage [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number	1	2
Pre-mod outstanding principal balance	108	695
Post-mod outstanding principal balance	110	695
Financial impact due to TDR taken as additional provision	8	37
RE Mortgage [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number	1	2
Pre-mod outstanding principal balance	124	256
Post-mod outstanding principal balance	124	259
Financial impact due to TDR taken as additional provision	-5	9
Number that defaulted during the period		1
Recorded investment of TDRs that defaulted during the period		260
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number	2
Pre-mod outstanding principal balance	89
Post-mod outstanding principal balance	89
Financial impact due to TDR taken as additional provision	5
C&I [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number	1	1
Pre-mod outstanding principal balance	287	38
Post-mod outstanding principal balance	288	38
Financial impact due to TDR taken as additional provision	164	18
Number that defaulted during the period		1
Recorded investment of TDRs that defaulted during the period		116
Financial impact due to the default of previous TDR taken as charge-offs or additional provisions		-8
Construction [Member] | Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number		1
Pre-mod outstanding principal balance		102
Post-mod outstanding principal balance		85
Construction [Member] | Commercial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number		1
Pre-mod outstanding principal balance		118
Post-mod outstanding principal balance		$100

Foreclosed_Assets_Summary_of_A

Foreclosed Assets - Summary of Activity in Balance of Foreclosed Assets (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	Assets	Assets
Schedule Of Foreclosed Assets Activity [Line Items]
Beginning balance, net	$4,894,000	$6,262,000
Additions/transfers from loans	1,560,000	1,175,000
Dispositions/sales	-495,000	-4,186,000
Valuation adjustments	-67,000	-36,000
Ending balance, net	5,892,000	3,215,000
Ending valuation allowance	263,000	121,000
Ending number of foreclosed assets	30	26
Proceeds from sale of foreclosed assets	806,000	5,413,000
Gain on sale of foreclosed assets	311,000	1,227,000
Noncovered [Member]
Schedule Of Foreclosed Assets Activity [Line Items]
Beginning balance, net	4,449,000	5,588,000
Additions/transfers from loans	1,560,000	1,175,000
Dispositions/sales	-495,000	-4,186,000
Valuation adjustments	-67,000	-26,000
Ending balance, net	5,447,000	2,551,000
Ending valuation allowance	263,000	111,000
Ending number of foreclosed assets	29	22
Proceeds from sale of foreclosed assets	806,000	5,413,000
Gain on sale of foreclosed assets	311,000	1,227,000
Covered [Member]
Schedule Of Foreclosed Assets Activity [Line Items]
Beginning balance, net	445,000	674,000
Valuation adjustments		-10,000
Ending balance, net	445,000	664,000
Ending valuation allowance		$10,000
Ending number of foreclosed assets	1	4

Foreclosed_Assets_Additional_I

Foreclosed Assets - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Schedule Of Foreclosed Assets Activity [Line Items]
Foreclosed assets	$5,892,000	$4,894,000	$3,215,000	$6,262,000
Residential Real Estate Properties [Member]
Schedule Of Foreclosed Assets Activity [Line Items]
Foreclosed assets	$1,691,000

Premises_and_Equipment_Summary

Premises and Equipment - Summary of Premises and Equipment (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment, Net, by Type [Abstract]
Land & land improvements	$8,883	$8,933
Buildings	38,939	39,638
Furniture and equipment	28,160	28,446
Premises and equipment, gross	75,982	77,017
Less: Accumulated depreciation	-33,152	-33,570
Premises and equipment less depreciation, gross	42,830	43,447
Construction in progress	16	46
Total premises and equipment	$42,846	$43,493

Premises_and_Equipment_Additio

Premises and Equipment - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Property, Plant and Equipment [Abstract]
Depreciation expense for premises and equipment	$1,268,000	$1,180,000

Cash_Value_of_Life_Insurance_S

Cash Value of Life Insurance - Summary of Activity in Balance of Cash Value of Life Insurance (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
	Policies	Company
	Company	Employees
	Employees	Policies
Increase (Decrease) in Insurance Liabilities [Abstract]
Beginning balance	$92,337	$52,309
Increase in cash value of life insurance	675	397
Ending balance	93,012	52,706
End of period death benefit	$165,847	$94,999
Number of policies owned	189	133
Insurance companies used	14	6
Current and former employees and directors covered	60	36

Cash_Value_of_Life_Insurance_A

Cash Value of Life Insurance - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
	Company	Company
	Policies
Insurance [Abstract]
Number of life insurance policies owned by the Company	189
Insurance companies used	14	6
Policies covering current and former employees and directors	60

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets - Summary of Goodwill Intangible (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Ending Balance	$63,462
Goodwill, Additions	0
Goodwill, Reductions	0
Goodwill, Beginning Balance	$63,462

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets - Summary of Core Deposit Intangibles (Detail) (Core deposit intangibles [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015
Core deposit intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Core deposit intangibles, Beginning balance	$8,074
Core deposit intangibles, Reductions/Amortization	0
Core deposit intangibles, Additions	0
Core deposit intangibles, Ending balance	8,074
Accumulated amortization, Beginning balance	-1,312
Accumulated amortization, Reductions/Amortization	-289
Accumulated amortization, Additions	0
Accumulated amortization, Ending balance	-1,023
Core deposit intangibles, net, Beginning balance	6,762
Core deposit intangibles, net, Reductions/Amortization	-289
Core deposit intangibles, net, Additions	0
Core deposit intangibles, net, Ending balance	$7,051

Goodwill_and_Other_Intangible_4

Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $)	Oct. 03, 2014	Sep. 23, 2011	28-May-10
North Valley Bancorp [Member]
Finite-Lived Intangible Assets [Line Items]
Additions to core deposit intangibles	$6,614,000
Citizens [Member]
Finite-Lived Intangible Assets [Line Items]
Additions to core deposit intangibles		898,000
Granite [Member]
Finite-Lived Intangible Assets [Line Items]
Additions to core deposit intangibles			$562,000

Goodwill_and_Other_Intangible_5

Goodwill and Other Intangible Assets - Estimated Core Deposit Intangible Amortization (Detail) (Core deposit intangibles [Member], USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Core deposit intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
2015	$1,157
2016	1,157
2017	1,109
2018	1,044
2019	948
Thereafter	$1,636

Mortgage_Servicing_Rights_Fair

Mortgage Servicing Rights - Fair Value of Mortgage Servicing Rights (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Servicing Assets at Fair Value [Line Items]
Contractually specified servicing fees, late fees and ancillary fees earned	$534	$420
Weighted-average prepayment speed (CPR)	13.00%	10.60%
Weighted-average discount rate	10.00%	10.00%
Loans [Member]
Servicing Assets at Fair Value [Line Items]
Balance at beginning of period			840,288	680,197
Balance at end of period	832,143	672,341	840,288	680,197
Mortgage servicing rights [Member]
Servicing Assets at Fair Value [Line Items]
Balance at beginning of period	7,378	6,165
Additions	185	123
Change in fair value	-506	-181
Balance at end of period	$7,057	$6,107

Indemnification_Asset_Summary_

Indemnification Asset - Summary of Activity in Balance of Indemnification Asset (Liability) (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
FDIC Indemnification Asset [Roll Forward]
Beginning balance	($349)	$206
Effect of actual and estimated future covered losses and recoveries	-62	-468
Reimbursable (revenue) expenses incurred	-3	59
Payments (received from) made to FDIC	-19	-17
Ending balance	-433	-220
Amount of indemnification asset (liability) recorded in other assets	114	-220
Amount of indemnification asset (liability) recorded in other liabilities	-547
Ending balance	($433)	($220)

Other_Assets_Summary_of_Other_

Other Assets - Summary of Other Assets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred tax asset, net	$36,994	$37,706
Prepaid expense	3,268	2,034
Software	1,198	1,327
Advanced compensation	825	908
Capital Trusts	1,691	1,690
Miscellaneous other assets	7,026	8,070
Total other assets	$51,002	$51,735

Deposits_Summary_of_Balances_o

Deposits - Summary of Balances of Deposits (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Deposits [Abstract]
Noninterest-bearing demand	$1,034,012	$1,083,900
Interest-bearing demand	795,471	782,385
Savings	1,172,257	1,156,126
Time certificates, $250,000 and over	37,181	38,217
Other time certificates	310,567	319,795
Total deposits	$3,349,488	$3,380,423

Deposits_Additional_Informatio

Deposits - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Schedule Of Deposits [Line Items]
Overdrawn deposit balances classified as consumer loans	$1,096,000	$1,216,000
California [Member]
Schedule Of Deposits [Line Items]
Certificate of deposits, included in time certificates $100,000 and over	$5,000,000	$5,000,000

Reserve_for_Unfunded_Commitmen2

Reserve for Unfunded Commitments - Summary of Activity in Reserve for Unfunded Commitments (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Balance at beginning of period	$2,145	$2,415
Provision for losses - Unfunded commitments	-130	-185
Balance at end of period	$2,015	$2,230

Other_Liabilities_Components_o

Other Liabilities - Components of Other Liabilities (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Other Liabilities Disclosure [Abstract]
Deferred compensation	$7,484	$7,408
Pension liability	27,074	26,798
Joint beneficiary agreements	2,785	2,728
Miscellaneous other liabilities	15,913	12,258
Total other liabilities	$53,256	$49,192

Other_Borrowings_Summary_of_Ba

Other Borrowings - Summary of Balances of Other Borrowings (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
Total other borrowings	$9,096	$9,276
Other collateralized borrowings, fixed rate, as of December 31, 2014 of 0.05%, payable on January 2, 2014 [Member]
Debt Instrument [Line Items]
Other collateralized borrowings, fixed rate, as of March 31, 2015 of 0.05%, payable on April 1, 2015	$9,096	$9,276

Other_Borrowings_Summary_of_Ba1

Other Borrowings - Summary of Balances of Other Borrowings (Parenthetical) (Detail) (Other collateralized borrowings, fixed rate, as of December 31, 2014 of 0.05%, payable on January 2, 2014 [Member])	3 Months Ended
	Mar. 31, 2015
Other collateralized borrowings, fixed rate, as of December 31, 2014 of 0.05%, payable on January 2, 2014 [Member]
Debt Instrument [Line Items]
Other collateralized borrowings, fixed rate	0.05%
Other collateralized borrowings, maturity date	1-Apr-15

Other_Borrowings_Additional_In

Other Borrowings - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
Security repurchase agreement	$0	$0
Other collateralized borrowings	9,096,000	9,276,000
Repurchase investment securities sold and pledged as collateral under securities repurchase agreement	9,096,000
FHLB collateral line of credit, maximum borrowings capacity	978,743,000
FHLB collateral line of credit, outstanding balance	0
FHLB collateral line of credit, remaining borrowing capacity	978,743,000
Loans designated as potential collateral under collateralized line of credit with FHLB	1,567,140,000
Collateralized line of credit with San Francisco Federal Reserve Bank, maximum borrowings capacity	138,447,000
Collateralized line of credit with San Francisco Federal Reserve Bank, outstanding balance	0
Collateralized line of credit with San Francisco Federal Reserve Bank, remaining borrowing capacity	138,447,000
Investment securities designated as potential collateral under collateral line of credit with San Francisco Federal Reserve Bank	427,000
Loans designated as potential collateral under collateral line of credit with San Francisco Federal Reserve Bank	205,883,000
Unused correspondent banking lines of credit from commercial banks for federal funds	$15,000,000

Junior_Subordinated_Debt_Addit

Junior Subordinated Debt - Additional Information (Detail) (USD $)	3 Months Ended	0 Months Ended
	Mar. 31, 2015	Oct. 03, 2014	Dec. 31, 2014	Jul. 31, 2003	Jun. 22, 2004
Class of Stock [Line Items]
Common stock shares issued	22,740,503		22,714,964
Subordinated debenture, Face Value	62,889,000
Subordinated debenture, recorded fair value	56,320,000		56,272,000
North Valley Bancorp [Member]
Class of Stock [Line Items]
Acquisition, completion date	3-Oct-14
North Valley Trust II [Member]
Class of Stock [Line Items]
Subordinated debenture, Face Value	6,186,000	6,186,000
Acquisition of common stock interests		186,000
Subordinated debenture, recorded fair value	5,025,000	5,006,000
North Valley Trust III [Member]
Class of Stock [Line Items]
Subordinated debenture, Face Value	5,155,000	5,155,000
Acquisition of common stock interests		155,000
Subordinated debenture, recorded fair value	3,936,000	3,918,000
North Valley Trust IV [Member]
Class of Stock [Line Items]
Subordinated debenture, Face Value	10,310,000	10,310,000
Acquisition of common stock interests		310,000
Subordinated debenture, recorded fair value	6,121,000	6,063,000
TriCo Capital Trust I [Member]
Class of Stock [Line Items]
Common stock shares issued				619
Common stock par value				$1,000
Issuance of common stock, aggregate value				619,000
Issued Junior Subordinated Debenture to the trust				20,619,000
Offering of cumulative trust preferred securities				20,000
Cumulative trust preferred securities for cash in an aggregate amount				20,000,000
Redeem the trust preferred securities	7-Oct-33
LIBOR Rate, Description	Three-month LIBOR plus 3.05%
Preferred securities redeemable interest rate	3.05%
Company paid underwriting fees, per trust preferred security	7.5
Company paid underwriting fees aggregate	150,000
Net proceeds were used to finance the opening of new branches, services and technology	19,850,000
TriCo Capital Trust II [Member]
Class of Stock [Line Items]
Common stock shares issued					619
Common stock par value					$1,000
Issuance of common stock, aggregate value					619,000
Issued Junior Subordinated Debenture to the trust					20,619,000
Offering of cumulative trust preferred securities					20,000
Cumulative trust preferred securities for cash in an aggregate amount					20,000,000
Redeem the trust preferred securities	23-Jul-34
LIBOR Rate, Description	Three-month LIBOR plus 2.55%
Preferred securities redeemable interest rate	2.55%
Company paid underwriting fees, per trust preferred security	2.5
Company paid underwriting fees aggregate	50,000
Net proceeds were used to finance the opening of new branches, services and technology	19,950,000

Junior_Subordinated_Debt_Summa

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	7-Oct-33
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	23-Jul-34
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	24-Apr-33
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	24-Apr-34
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	15-Mar-36
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%

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Aug. 21, 2007
	site
Conversion of Stock [Line Items]
Reserves to satisfy Federal regulatory requirements	$64,997,000		$57,616,000
Number of sites leased under non-cancelable operating leases	47
Rent expense under operating leases	959,000	755,000
Rent expense offset by rent income	48,000	54,000
Commitment expiration date	One year or less or other termination clauses and may require payment of a fee.
Letters of credit, issue period	One year or less
Overdraft privilege receivable criteria	All holders of such accounts who bring their accounts to a positive balance at least once every thirty days receive the overdraft privilege.
Class B common stock of Visa Inc.	22,740,503		22,714,964	15,814,662
Conversion ratio	1.648265
Common Class B [Member]
Conversion of Stock [Line Items]
Class B common stock of Visa Inc.	13,396
Common Class A [Member]
Conversion of Stock [Line Items]
The value of the Class A shares	$65.41
Value of unredeemed Class A equivalent shares	$1,444,000

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Commitments under Non-Cancelable Operating Leases with Initial or Remaining Terms of One Year or More (Detail) (USD $)	Dec. 31, 2014
In Thousands, unless otherwise specified
Leases [Abstract]
2015	$3,419
2016	2,510
2017	1,856
2018	1,323
2019	859
Thereafter	1,180
Future minimum lease payments	$11,147

Commitments_and_Contingencies_3

Commitments and Contingencies - Summary of Bank's Commitments and Contingent Liabilities (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit
Real estate construction loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	40,935	49,774
Deposit account overdraft privilege [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	99,002	101,060
RE Mortgage [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	40,014	36,139
Standby letters of credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	16,307	17,531
Commercial [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	195,295	177,557
Other Consumer [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to extend credit	$392,005	$392,705

Shareholders_Equity_Additional

Shareholders' Equity - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Aug. 21, 2007	Dec. 31, 2013
Class of Stock [Line Items]
Dividend payable by bank			$52,798,000
Shareholder Rights Plan	25-Jun-01
Percentage of restriction on acquiring outstanding common stock by person or group	15.00%
Repurchase of common stock				500,000
Stock repurchase plan percentage of common stock				3.20%
Common stock, shares outstanding	22,740,503		22,714,964	15,814,662
Repurchased shares outstanding	166,600
Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares outstanding	22,740,503	16,120,297	22,714,964		16,076,662
Company's common stock in lieu of cash to exercise options to purchase shares	21,461	100,385
Market value of common stock	509,000	2,482,000
Mellon Investor Services LLC [Member] | Amendment [Member]
Class of Stock [Line Items]
Amendment date of Right Plan	4-Jun-14
Schedule expiration date plan	1-Jul-14
Tri Counties Bank [Member]
Class of Stock [Line Items]
Cash dividends received	$2,120,000	$2,050,000

Stock_Options_and_Other_Equity2

Stock Options and Other Equity-Based Incentive Instruments - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended	0 Months Ended				12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Aug. 11, 2018	Aug. 11, 2017	Aug. 11, 2016	Aug. 11, 2015	Dec. 31, 2014	Mar. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options under the plan	1,055,850	1,102,850						1,102,850
Options currently not exercisable yet expected to vest	283,000
Weighted-average remaining contractual term	2 years 3 months 18 days
Pre-tax compensation costs expected to recognize	$1,562,000
Restricted Stock Units (RSUs) [Member] | Service Condition Vesting RSUs [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of units outstanding expected to vest	31,061	30,920						30,920
Weighted-average remaining contractual term	2 years 7 months 6 days
Pre-tax compensation costs	489,000
Number of units granted	0	13,749	0
RSUs vesting grant date	11-Aug-14
Number of units released	0
Restricted Stock Units (RSUs) [Member] | Service Condition Vesting RSUs [Member] | Forecast [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Percentage of vesting schedule				25.00%	25.00%	25.00%	25.00%
Restricted Stock Units (RSUs) [Member] | Market Plus Service Condition Vesting RSUs [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of units outstanding expected to vest	15,366	15,366						15,366
Weighted-average remaining contractual term	2 years 4 months 24 days
Pre-tax compensation costs	$259,000
Number of units granted	0							0
Number of units released	0
Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Maximum aggregate number of shares of TriCo's common stock issued	650,000
Minimum [Member] | Restricted Stock Units (RSUs) [Member] | Market Plus Service Condition Vesting RSUs [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of units released	0
Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Maximum aggregate number of shares of TriCo's common stock issued									1,650,000
Maximum [Member] | Restricted Stock Units (RSUs) [Member] | Market Plus Service Condition Vesting RSUs [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of units released	23,049
2009 Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares to be reduced pursuant to stock option for computation of available number of shares for issuance	1
Number of shares to be reduced pursuant to restricted stock award for computation of available number of shares for issuance	2
Outstanding options under the plan	694,000
Options available for grant under the plan	822,146
2009 Plan [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of units outstanding expected to vest	46,427
2001 Plan [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding options under the plan	361,850
Options available for grant under the plan	0
Share based compensation grant expiry period	10 years

Stock_Options_and_Other_Equity3

Stock Options and Other Equity-Based Incentive Instruments - Stock Option Activity (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, Number of Shares, beginning balance	1,102,850
Options granted, Number of Shares	0
Options exercised, Number of Shares	-47,000
Options forfeited, Number of Shares	0
Options outstanding, Number of Shares, ending balance	1,055,850
Options outstanding, Weighted Average Exercise Price, beginning balance	$18.25
Options granted, Weighted Average Exercise Price	$0
Options exercised, Weighted Average Exercise Price	$18.86
Options forfeited, Weighted Average Exercise Price	$0
Options outstanding, Weighted Average Exercise Price, ending balance	$18.22
Outstanding, Weighted Average Fair Value on Date of Grant, beginning balance	$0	$0
Options granted, Weighted Average Fair Value on Date of Grant	$0
Options exercised, Weighted Average Fair Value on Date of Grant	$0
Options forfeited, Weighted Average Fair Value on Date of Grant	$0
Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, Option Price per Share, beginning balance	$12.63
Options granted, Option Price per Share	$0
Options exercised, Option Price per Share	$15.34
Options forfeited, Option Price per Share	$0
Options outstanding, Option Price per Share, ending balance	$12.63
Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, Option Price per Share, beginning balance	$25.91
Options granted, Option Price per Share	$0
Options exercised, Option Price per Share	$19.46
Options forfeited, Option Price per Share	$0
Options outstanding, Option Price per Share, ending balance	$25.91

Stock_Options_and_Other_Equity4

Stock Options and Other Equity-Based Incentive Instruments - Summary of Options Outstanding (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options	1,055,850
Weighted average exercise price	$18.22
Intrinsic value (in thousands)	$6,296
Weighted average remaining contractual term (yrs.)	5 years 2 months 12 days
Currently Exercisable [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options	772,850
Weighted average exercise price	$18.60
Intrinsic value (in thousands)	4,334
Weighted average remaining contractual term (yrs.)	4 years 4 months 24 days
Currently Not Exercisable [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of options	283,000
Weighted average exercise price	$17.20
Intrinsic value (in thousands)	$1,962
Weighted average remaining contractual term (yrs.)	7 years 3 months 18 days

Stock_Options_and_Other_Equity5

Stock Options and Other Equity-Based Incentive Instruments - Restricted Stock Unit (RSU) Activity (Detail) (USD $)	3 Months Ended		9 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, Weighted Average Fair Value on Date of Grant, beginning balance	$0
RSUs granted, Weighted Average Fair Value on Date of Grant	$0
RSUs added through dividend credits, Weighted Average Fair Value on Date of Grant	$0
RSUs released, Weighted Average Fair Value on Date of Grant	$0
RSUs forfeited/expired, Weighted Average Fair Value on Date of Grant	$0
Outstanding, Weighted Average Fair Value on Date of Grant, ending balance	$0
Restricted Stock Units (RSUs) [Member] | Service Condition Vesting RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding, Number of RSUs, beginning balance	30,920
RSUs granted, Number of RSUs	0	13,749	0
RSUs added through dividend credits, Number of RSUs	141
RSUs released, Number of RSUs	0
RSUs forfeited/expired, Number of RSUs	0
RSUs outstanding, Number of RSUs, ending balance	31,061	30,920		30,920
Restricted Stock Units (RSUs) [Member] | Market Plus Service Condition Vesting RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs outstanding, Number of RSUs, beginning balance	15,366
RSUs granted, Number of RSUs	0			0
RSUs released, Number of RSUs	0
RSUs forfeited/expired, Number of RSUs	0
RSUs outstanding, Number of RSUs, ending balance	15,366	15,366		15,366
Outstanding, Weighted Average Fair Value on Date of Grant, beginning balance	$0
RSUs granted, Weighted Average Fair Value on Date of Grant	$0
RSUs added through dividend credits, Weighted Average Fair Value on Date of Grant	$0
RSUs released, Weighted Average Fair Value on Date of Grant	$0
RSUs forfeited/expired, Weighted Average Fair Value on Date of Grant	$0
Outstanding, Weighted Average Fair Value on Date of Grant, ending balance	$0	0		$0

Noninterest_Income_and_Expense2

Noninterest Income and Expense - Components of Other Noninterest Income (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Income Statement [Abstract]
Service charges on deposit accounts	$3,600				$2,690
ATM and interchange fees	3,002				2,013
Other service fees	714				520
Mortgage banking service fees	534				420
Change in value of mortgage servicing rights	-506				-181
Total service charges and fees	7,344				5,462
Gain on sale of loans	622				464
Commissions on sale of non-deposit investment products	965				771
Increase in cash value of life insurance	675				397
Change in indemnification asset	-65				-412
Gain on sale of foreclosed assets	311				1,227
Sale of customer checks	128				101
Lease brokerage income	137				107
Loss on disposal of fixed assets	-84				-1
Other	147				179
Total other noninterest income	2,836				2,833
Total noninterest income	$10,180	$9,755	$8,589	$7,877	$8,295

Noninterest_Income_and_Expense3

Noninterest Income and Expense - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Mortgage loan servicing fees, net of change in fair value of mortgage loan servicing rights	$28,000	$239,000

Noninterest_Income_and_Expense4

Noninterest Income and Expense - Components of Noninterest Expense (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Schedule Of Other Noninterest Income And Expense [Line Items]
Base salaries, net of deferred loan origination costs	$11,744				$8,866
Incentive compensation	1,596				1,123
Benefits and other compensation costs	4,760				3,314
Total salaries and benefits expense	18,100				13,303
Occupancy	2,417				1,962
Equipment	1,414				1,036
Data processing and software	1,952				1,178
ATM network charges	770				643
Telecommunications	886				580
Postage	312				227
Courier service	248				234
Advertising	808				342
Assessments	651				521
Operational losses	124				177
Professional fees	1,119				614
Foreclosed assets expense	98				158
Provision for foreclosed asset losses	67				36
Reserve for unfunded commitments	-130				-185
Intangible amortization	289				52
Merger expense	586				225
Other	2,571				2,214
Total other noninterest expense	14,182				10,014
Total noninterest expense	32,282	36,566	25,380	25,116	23,317
Merger expense:
Merger expense	586				225
Merger expense	586				225
North Valley Bancorp [Member] | Data processing and software [Member]
Schedule Of Other Noninterest Income And Expense [Line Items]
Merger expense	108
Merger expense:
Merger expense	108
Merger expense	108
North Valley Bancorp [Member] | Professional fees [Member]
Schedule Of Other Noninterest Income And Expense [Line Items]
Merger expense	120				225
Merger expense:
Merger expense	120				225
Merger expense	120				225
North Valley Bancorp [Member] | Other [Member]
Schedule Of Other Noninterest Income And Expense [Line Items]
Merger expense	358
Merger expense:
Merger expense	358
Merger expense	$358

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Effective Tax Rate and Statutory Federal Income Tax Rate (Detail)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Income Tax Disclosure [Abstract]
Federal statutory income tax rate	35.00%	35.00%
State income taxes, net of federal tax benefit	6.90%	6.90%
Tax-exempt interest on municipal obligations	-0.40%	-0.40%
Increase in cash value of insurance policies	-1.70%	-1.10%
Other	0.80%	0.20%
Effective Tax Rate	40.60%	40.60%

Earnings_Per_Share_Computation

Earnings Per Share - Computation of Earnings Per Share (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Earnings Per Share [Abstract]
Net income	$8,336	$5,650	$8,234	$4,859	$7,365
Average number of common shares outstanding	22,727				16,097
Effect of dilutive stock options and restricted stock	223				225
Average number of common shares outstanding used to calculate diluted earnings per share	22,950				16,322
Options excluded from diluted earnings per share because the effect of these options was antidilutive	23				101

Comprehensive_Income_Component

Comprehensive Income - Components of Other Comprehensive Income and Related Tax Effects (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Equity [Abstract]
Unrealized holding gains (losses) on available for sale securities before reclassifications	$15	($105)
Amounts reclassified out of accumulated other comprehensive income-	0	0
Unrealized holding gains (losses) on available for sale securities after reclassifications	15	-105
Tax effect	-6	45
Unrealized holding gains (losses) on available for sale securities, net of tax	9	-60
Change in unfunded status of the supplemental retirement plans before reclassifications	0	0
Amounts reclassified out of accumulated other comprehensive income:
Amortization of prior service cost	-14	5
Amortization of actuarial losses	206	4
Total amounts reclassified out of accumulated other comprehensive income	192	9
Change in unfunded status of the supplemental retirement plans after reclassifications	192	9
Tax effect	-81	-4
Change in unfunded status of the supplemental retirement plans, net of tax	111	5
Change in joint beneficiary agreement liability before reclassifications	0	0
Amounts reclassified out of accumulated other comprehensive income	0	0
Change in joint beneficiary agreement liability after reclassifications	0	0
Tax effect	0	0
Change in joint beneficiary agreement liability, net of tax	0	0
Total other comprehensive gain (loss)	$120	($55)

Comprehensive_Income_Component1

Comprehensive Income - Components of Accumulated Other Comprehensive Income (Detail) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Equity [Abstract]
Net unrealized gains on available for sale securities	$4,055	$4,040
Tax effect	-1,705	-1,699
Unrealized holding gains on available for sale securities, net of tax	2,350	2,341
Unfunded status of the supplemental retirement plans	-7,693	-7,885
Tax effect	3,234	3,315
Unfunded status of the supplemental retirement plans, net of tax	-4,459	-4,570
Joint beneficiary agreement liability	26	26
Tax effect	0	0
Joint beneficiary agreement liability, net of tax	26	26
Accumulated other comprehensive loss	($2,083)	($2,203)

Retirement_Plans_Additional_In

Retirement Plans - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Employee service period under ESOP	1 year
Deferred compensation obligations	$7,484,000		$7,408,000
Earnings credits on deferred balances included in noninterest expense	149,000	152,000
401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Minimum age for employees	21 years
Minimum period for employees to participate	90 days
Employee Stock Ownership Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution and paid out as benefits	368,000	195,000
Supplemental Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution and paid out as benefits	219,000	125,000
Supplemental Retirement Plans [Member] | December 31, 2015 [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution and paid out as benefits	$1,194,000

Retirement_Plans_Net_Periodic_

Retirement Plans - Net Periodic Benefit Cost Recognized for Supplemental Retirement Plans (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Net pension cost included the following components:
Service cost-benefits earned during the period	$256	$163
Interest cost on projected benefit obligation	239	174
Amortization of net obligation at transition	0	0
Amortization of prior service cost	-14	35
Recognized net actuarial loss	206	4
Net periodic pension cost	$687	$376

Related_Party_Transactions_Sum

Related Party Transactions - Summary of Loan Activity (Detail) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Related Party Transaction, Due from (to) Related Party, Noncurrent [Abstract]
Beginning balance	$3,132	$2,636
Advances/new loans	235	2,106
Removed/payments	-416	-1,610
Ending balance	$2,951	$3,132

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail) (Modern Building Inc. [Member], USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Modern Building Inc. [Member]
Related Party Transaction [Line Items]
Aggregate payments for construction services	$166,000	$1,181,000

Fair_Value_Measurement_Recorde

Fair Value Measurement - Recorded Amount of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$6,074	$5,091	$22,300
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	6,074	5,091	22,300
Fair value measurements on recurring basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	232,183	90,583
Fair value measurements on recurring basis [Member] | Obligations of U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	210,535	75,120
Fair value measurements on recurring basis [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,656	3,175
Fair value measurements on recurring basis [Member] | Corporate debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	1,905	1,908
Fair value measurements on recurring basis [Member] | Marketable equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	3,030	3,002
Fair value measurements on recurring basis [Member] | Mortgage servicing rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	7,057	7,378
Fair value measurements on recurring basis [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	3,030	3,002
Fair value measurements on recurring basis [Member] | Level 1 [Member] | Marketable equity securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	3,030	3,002
Fair value measurements on recurring basis [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	222,096	80,203
Fair value measurements on recurring basis [Member] | Level 2 [Member] | Obligations of U.S. government corporations and agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	210,535	75,120
Fair value measurements on recurring basis [Member] | Level 2 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,656	3,175
Fair value measurements on recurring basis [Member] | Level 2 [Member] | Corporate debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	1,905	1,908
Fair value measurements on recurring basis [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	7,057	7,378
Fair value measurements on recurring basis [Member] | Level 3 [Member] | Mortgage servicing rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$7,057	$7,378

Fair_Value_Measurement_Additio

Fair Value Measurement - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers between any levels	$0	$0
Carrying value of loans fully charged-off	0
Securities held to maturity	802,482,000	676,426,000
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities held to maturity	$0	$0

Fair_Value_Measurement_Reconci

Fair Value Measurement - Reconciliation of Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) on Recurring Basis (Detail) (Mortgage servicing rights [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Mortgage servicing rights [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$7,378	$6,165
Transfers into (out of) Level 3	0	0
Change Included in Earnings	-506	-181
Issuances	185	123
Ending Balance	$7,057	$6,107

Fair_Value_Measurement_Quantit

Fair Value Measurement - Quantitative Information about Recurring Level 3 Fair Value Measurements (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	13.00%	10.60%
Discount rate	10.00%	10.00%
Mortgage servicing rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortgages Servicing Rights, Fair Value	7,057		7,378
Minimum [Member] | Mortgage servicing rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	10.00%		10.00%
Minimum [Member] | Mortgage servicing rights [Member] | Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	6.00%		5.70%
Maximum [Member] | Mortgage servicing rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	12.00%		12.00%
Maximum [Member] | Mortgage servicing rights [Member] | Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	23.10%		23.40%
Weighted Average [Member] | Mortgage servicing rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	10.00%		10.00%
Weighted Average [Member] | Mortgage servicing rights [Member] | Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	13.00%		12.00%

Fair_Value_Measurement_Assets_

Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Nonrecurring Basis (Detail) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$6,074	$22,300	$5,091
Total Losses	-245	-293	-773
Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	3,690	21,498	2,480
Total Losses	-181	-272	-636
Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	2,384	802	2,611
Total Losses	-64	-21	-137
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	6,074	22,300	5,091
Level 3 [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	3,690	21,498	2,480
Level 3 [Member] | Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$2,384	$802	$2,611

Fair_Value_Measurement_Quantit1

Fair Value Measurement - Quantitative Information about Level 3 Fair Value Measurements for Financial Instruments Measured at Fair Value on Nonrecurring Basis (Detail) (USD $)	3 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	6,074	5,091	$22,300
Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,690	2,480	21,498
Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,384	2,611	802
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	6,074	5,091	22,300
Level 3 [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	3,690	2,480	21,498
Level 3 [Member] | Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	2,384	2,611	$802
Level 3 [Member] | Sales comparison approach [Member] | Minimum [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-5.00%	-5.00%
Level 3 [Member] | Sales comparison approach [Member] | Minimum [Member] | Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-5.00%	-5.00%
Level 3 [Member] | Sales comparison approach [Member] | Maximum [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-41.00%	-42.50%
Level 3 [Member] | Sales comparison approach [Member] | Maximum [Member] | Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-30.10%	-29.40%
Level 3 [Member] | Sales comparison approach [Member] | Weighted Average [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-8.80%	-10.10%
Level 3 [Member] | Sales comparison approach [Member] | Weighted Average [Member] | Foreclosed assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Adjustment for differences between comparable sales	-9.30%	-8.20%
Level 3 [Member] | Income approach [Member] | Minimum [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Capitalization rate	8.00%	9.09%
Level 3 [Member] | Income approach [Member] | Maximum [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Capitalization rate	9.10%	9.09%
Level 3 [Member] | Income approach [Member] | Weighted Average [Member] | Impaired Originated & PNCI loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Capitalization rate	8.10%	9.09%

Fair_Value_Measurement_Estimat

Fair Value Measurement - Estimated Fair Values of Financial Instruments that are Reported at Amortized Cost in Consolidated Balance Sheets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Financial assets:
Cash and due from banks	$84,682,000	$93,150,000
Cash at Federal Reserve and other banks	196,546,000	517,578,000
Securities held to maturity	802,482,000	676,426,000
Indemnification (liability) asset	-433,000	-349,000	-220,000	206,000
Financial liabilities:
Other borrowings	9,096,000	9,276,000
Junior subordinated debt	56,320,000	56,272,000
Level 3 [Member]
Financial assets:
Securities held to maturity	0	0
Contract Amount [Member] | Level 3 [Member]
Off-balance sheet:
Commitments	668,249,000	656,175,000
Standby letters of credit	16,307,000	17,531,000
Overdraft privilege commitments	99,002,000	101,060,000
Fair Value [Member] | Level 3 [Member]
Financial assets:
Loans, net	2,379,343,000	2,342,570,000
Indemnification (liability) asset	-433,000	-349,000
Off-balance sheet:
Commitments	6,682,000	6,562,000
Standby letters of credit	163,000	175,000
Overdraft privilege commitments	990,000	1,011,000
Fair Value [Member] | Level 1 [Member]
Financial assets:
Cash and due from banks	84,682,000	93,150,000
Cash at Federal Reserve and other banks	196,546,000	517,578,000
Fair Value [Member] | Level 2 [Member]
Financial assets:
Securities held to maturity	817,793,000	688,779,000
Loans held for sale	5,413,000	3,579,000
Financial liabilities:
Deposits	3,349,507,000	3,380,486,000
Other borrowings	9,096,000	9,276,000
Junior subordinated debt	46,424,000	45,053,000
Carrying Amount [Member] | Level 3 [Member]
Financial assets:
Loans, net	2,284,828,000	2,245,938,000
Indemnification (liability) asset	-433,000	-349,000
Carrying Amount [Member] | Level 1 [Member]
Financial assets:
Cash and due from banks	84,682,000	93,150,000
Cash at Federal Reserve and other banks	196,546,000	517,578,000
Carrying Amount [Member] | Level 2 [Member]
Financial assets:
Securities held to maturity	802,482,000	676,426,000
Restricted equity securities	16,956,000	16,956,000
Loans held for sale	5,413,000	3,579,000
Financial liabilities:
Deposits	3,349,488,000	3,380,423,000
Other borrowings	9,096,000	9,276,000
Junior subordinated debt	$56,320,000	$56,272,000

TriCo_Bancshares_Condensed_Fin2

TriCo Bancshares Condensed Financial Statements (Parent Only) - Condensed Balance Sheets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Assets
Cash and Cash equivalents	$281,228,000	$610,728,000	$502,251,000	$598,368,000
Other assets	51,002,000	51,735,000
Total assets	3,895,860,000	3,916,458,000
Liabilities and shareholders' equity
Other liabilities	53,256,000	49,192,000
Junior subordinated debt	56,320,000	56,272,000
Total liabilities	3,471,027,000	3,498,286,000
Shareholders' equity:
Common stock, no par value: authorized 50,000,000 shares; issued and outstanding 22,740,503 and 22,714,964 shares, respectively	245,316,000	244,318,000
Retained earnings	181,600,000	176,057,000
Accumulated other comprehensive loss, net	-2,083,000	-2,203,000
Total shareholders' equity	424,833,000	418,172,000	256,977,000	250,946,000
Total liabilities and shareholders' equity	3,895,860,000	3,916,458,000
Parent [Member]
Assets
Cash and Cash equivalents	2,044,000	2,229,000	2,383,000	2,520,000
Investment in Tri Counties Bank	477,845,000	470,797,000
Other assets	1,738,000	1,902,000
Total assets	481,627,000	474,928,000
Liabilities and shareholders' equity
Other liabilities	474,000	484,000
Junior subordinated debt	56,320,000	56,272,000
Total liabilities	56,794,000	56,756,000
Shareholders' equity:
Common stock, no par value: authorized 50,000,000 shares; issued and outstanding 22,740,503 and 22,714,964 shares, respectively	245,316,000	244,318,000
Retained earnings	181,600,000	176,057,000
Accumulated other comprehensive loss, net	-2,083,000	-2,203,000
Total shareholders' equity	424,833,000	418,172,000
Total liabilities and shareholders' equity	$481,627,000	$474,928,000

TriCo_Bancshares_Condensed_Fin3

TriCo Bancshares Condensed Financial Statements (Parent Only) - Condensed Balance Sheets (Parenthetical) (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Aug. 21, 2007
Condensed Financial Statements, Captions [Line Items]
Common stock, par value
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	22,740,503	22,714,964
Common stock, shares outstanding	22,740,503	22,714,964	15,814,662
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Common stock, par value
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	22,740,503	22,714,964
Common stock, shares outstanding	22,740,503	22,714,964

TriCo_Bancshares_Condensed_Fin4

TriCo Bancshares Condensed Financial Statements (Parent Only) - Condensed Statements of Income (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Interest expense	$1,382	$1,437	$1,082	$1,075	$1,087
Income before income taxes	14,044	9,580	14,235	8,396	12,405
Equity in net income of Tri Counties Bank:
Income tax benefit	5,708	3,930	6,001	3,537	5,040
Net income	8,336	5,650	8,234	4,859	7,365
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Interest expense	482				304
Administration expense	153				324
Income before income taxes	-635				-628
Equity in net income of Tri Counties Bank:
Distributed	2,120				2,050
Under distributed	6,584				5,679
Income tax benefit	267				264
Net income	$8,336				$7,365

TriCo_Bancshares_Condensed_Fin5

TriCo Bancshares Condensed Financial Statements (Parent Only) - Condensed Statements of Comprehensive Income (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Net income	$8,336	$5,650	$8,234	$4,859	$7,365
Other comprehensive loss, net of tax:
Increase (decrease) in unrealized gains on available for sale securities arising during the period	9				-60
Change in minimum pension liability	111				5
Other comprehensive loss	120				-55
Comprehensive income	8,456				7,310
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	8,336				7,365
Other comprehensive loss, net of tax:
Increase (decrease) in unrealized gains on available for sale securities arising during the period	9				-60
Change in minimum pension liability	111				5
Other comprehensive loss	120				-55
Comprehensive income	$8,456				$7,310

TriCo_Bancshares_Condensed_Fin6

TriCo Bancshares Condensed Financial Statements (Parent Only) - Condensed Statements of Cash Flows (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Operating activities:
Net income	$8,336	$5,650	$8,234	$4,859	$7,365
Adjustments to reconcile net income to net cash provided by operating activities:
Equity compensation vesting expense	324				296
Stock option excess tax benefits	-18				-184
Net cash provided by operating activities	12,961				12,286
Financing activities:
Stock option excess tax benefits	18				184
Repurchase of common stock	-27				-293
Cash dividends paid - common	-2,515				-1,772
Net cash used for financing activities	-33,234				-554
Net change in cash and cash equivalents	-329,500				-96,117
Cash and cash equivalents and beginning of year	610,728			502,251	598,368
Cash and cash equivalents at end of year	281,228	610,728			502,251
Parent [Member]
Operating activities:
Net income	8,336				7,365
Adjustments to reconcile net income to net cash provided by operating activities:
Under distributed equity in earnings of Tri Counties Bank	-6,584				-5,679
Equity compensation vesting expense	324				296
Stock option excess tax benefits	-18				-184
Net change in other assets and liabilities	-124				-360
Net cash provided by operating activities	1,934				1,438
Financing activities:
Stock option excess tax benefits	18				184
Issuance of common stock through option exercise	405				306
Repurchase of common stock	-27				-293
Cash dividends paid - common	-2,515				-1,772
Net cash used for financing activities	-2,119				-1,575
Net change in cash and cash equivalents	-185				-137
Cash and cash equivalents and beginning of year	2,229				2,520
Cash and cash equivalents at end of year	$2,044				$2,383

Regulatory_Matters_Actual_and_

Regulatory Matters - Actual and Required Capital Ratios of Bank (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount		$279,311
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount		167,587
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount		185,918
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio		10.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio		6.00%
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio		5.00%
Parent [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Actual, Amount	444,192	436,955
Tier 1 Capital (to Risk Weighted Assets), Actual, Amount	407,722	401,971
Tier 1 Capital (to Average Assets), Actual, Amount	407,722	401,971
Total Capital (to Risk Weighted Assets), Actual, Ratio	15.23%	15.63%
Tier 1 Capital (to Risk Weighted Assets), Actual, Ratio	13.98%	14.38%
Tier 1 Capital (to Average Assets), Actual, Ratio	10.68%	10.80%
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount		223,603
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount		111,801
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount		148,819
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio		8.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio		4.00%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio		4.00%
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	291,598
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	233,279
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	190,935
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%
Parent [Member] | Basel III Phase-in Schedule [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	233,279
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	174,959
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount	152,748
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	8.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	6.00%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio	4.00%
Parent [Member] | Basel III Fully Phased In [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	306,178
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	247,858
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount	152,748
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	10.50%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	8.50%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio	4.00%
Parent [Member] | Common Stock [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Actual, Amount	353,131
Tier 1 Capital (to Risk Weighted Assets), Actual, Ratio	12.11%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	189,426
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%
Parent [Member] | Common Stock [Member] | Basel III Phase-in Schedule [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	131,219
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	4.50%
Parent [Member] | Common Stock [Member] | Basel III Fully Phased In [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	204,119
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	7.00%
Tri Countries Bank [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Actual, Amount	442,590	433,286
Tier 1 Capital (to Risk Weighted Assets), Actual, Amount	406,142	398,325
Tier 1 Capital (to Average Assets), Actual, Amount	406,142	398,325
Total Capital (to Risk Weighted Assets), Actual, Ratio	15.19%	15.51%
Tier 1 Capital (to Risk Weighted Assets), Actual, Ratio	13.94%	14.26%
Tier 1 Capital (to Average Assets), Actual, Ratio	10.64%	10.71%
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount		223,449
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount		111,724
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount		148,734
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio		8.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio		4.00%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio		4.00%
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	291,422
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	233,138
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	190,845
Total Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Tier 1 Capital (to Average Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%
Tri Countries Bank [Member] | Basel III Phase-in Schedule [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	233,138
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	174,853
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount	152,676
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	8.00%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	6.00%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio	4.00%
Tri Countries Bank [Member] | Basel III Fully Phased In [Member]
Schedule of Capitalization [Line Items]
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	305,993
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	247,709
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Amount	152,676
Total Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	10.50%
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	8.50%
Tier 1 Capital (to Average Assets), Minimum Capital Requirement, Ratio	4.00%
Tri Countries Bank [Member] | Common Stock [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Actual, Amount	406,142
Tier 1 Capital (to Risk Weighted Assets), Actual, Ratio	13.94%
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	189,539
Tier 1 Capital (to Risk Weighted Assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%
Tri Countries Bank [Member] | Common Stock [Member] | Basel III Phase-in Schedule [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	131,140
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	4.50%
Tri Countries Bank [Member] | Common Stock [Member] | Basel III Fully Phased In [Member]
Schedule of Capitalization [Line Items]
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Amount	$203,996
Tier 1 Capital (to Risk Weighted Assets), Minimum Capital Requirement, Ratio	7.00%

Summary_of_Quarterly_Results_o2

Summary of Quarterly Results of Operations (Unaudited) - Result of Operations (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Loans:
Discount accretion PCI - cash basis	$172	$107	$290	$69	$203
Discount accretion PCI - other	1,274	919	822	811	984
Discount accretion PNCI	1,348	796	402	624	379
All other loan interest income	28,371	28,914	23,466	22,929	22,172
Total loan interest income	31,165	30,736	24,980	24,433	23,738
Debt securities, dividends and interest bearing cash at Banks (not FTE)	6,560	5,671	4,151	3,985	3,421
Total interest and dividend income	37,725	36,407	29,131	28,418	27,159
Interest expense	1,382	1,437	1,082	1,075	1,087
Net interest income	36,343	34,970	28,049	27,343	26,072
(Benefit from) provision for loan losses	197	-1,421	-2,977	1,708	-1,355
Net interest income after provision for loan losses	36,146	36,391	31,026	25,635	27,427
Noninterest income	10,180	9,755	8,589	7,877	8,295
Noninterest expense	32,282	36,566	25,380	25,116	23,317
Income before income taxes	14,044	9,580	14,235	8,396	12,405
Income tax expense	5,708	3,930	6,001	3,537	5,040
Net income	$8,336	$5,650	$8,234	$4,859	$7,365
Per common share:
Net income (diluted)	$0.36	$0.25	$0.50	$0.30	$0.45
Dividends	$0.11	$0.11	$0.11	$0.11	$0.11

Subsequent_Event_Additional_In

Subsequent Event - Additional Information (Detail) (Subsequent Event [Member])	0 Months Ended
	Apr. 29, 2015
	Branches
Subsequent Event [Line Items]
Number of additional branches identified for closure	5
Expected date of closure of additional branches	30-Sep-15
North Valley Bancorp [Member]
Subsequent Event [Line Items]
Number of additional branches identified for closure	2