Westamerica Bancorporation (WABC) 10-K 27 Feb 18 2017 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Feb. 13, 2018	Jun. 30, 2017
Document Information [Line Items]
Entity Registrant Name	WESTAMERICA BANCORPORATION
Entity Central Index Key	311,094
Trading Symbol	wabc
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Common Stock, Shares Outstanding (in shares)		26,567,573
Entity Public Float			$ 1,081,997,447
Document Type	10-K
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets:
Cash and due from banks	$ 575,002	$ 462,271
Investment securities available for sale	2,193,507	1,890,758
Investment securities held to maturity, with fair values of: $1,155,342 at December 31, 2017 and $1,340,741 at December 31, 2016	1,158,864	1,346,312
Loans	1,287,982	1,352,711
Allowance for loan losses	(23,009)	(25,954)
Loans, net of allowance for loan losses	1,264,973	1,326,757
Other real estate owned	1,426	3,095
Premises and equipment, net	35,301	36,566
Identifiable intangibles, net	3,850	6,927
Goodwill	121,673	121,673
Other assets	158,450	171,724
Total Assets	5,513,046	5,366,083
Liabilities:
Noninterest-bearing deposits	2,197,526	2,089,443
Interest-bearing deposits	2,630,087	2,615,298
Total deposits	4,827,613	4,704,741
Short-term borrowed funds	58,471	59,078
Other liabilities	36,723	40,897
Total Liabilities	4,922,807	4,804,716
Contingencies (Note 13)
Shareholders' Equity:
Common stock (no par value), authorized - 150,000 shares Issued and outstanding: 26,425 at December 31, 2017 and 25,907 at December 31, 2016	431,734	404,606
Deferred compensation	1,533	1,533
Accumulated other comprehensive loss	(16,832)	(10,074)
Retained earnings	173,804	165,302
Total Shareholders' Equity	590,239	561,367
Total Liabilities and Shareholders' Equity	$ 5,513,046	$ 5,366,083

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parentheticals) - USD ($) shares in Thousands, $ / shares in Thousands, $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment securities held to maturity, fair values	$ 1,155,342	$ 1,340,741
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, authorized (in shares)	150,000	150,000
Common stock, issued (in shares)	26,425	25,907
Common stock, outstanding (in shares)	26,425	25,907

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest and Loan Fee Income:
Loans	$ 61,740	$ 69,139	$ 78,441
Investment securities available for sale	44,664	34,276	31,263
Investment securities held to maturity	27,432	30,636	26,825
Total Interest and Loan Fee Income	133,836	134,051	136,529
Interest Expense:
Deposits	1,856	2,077	2,370
Short-term borrowed funds	44	39	53
Federal Home Loan Bank advances			1
Total Interest Expense	1,900	2,116	2,424
Net Interest and Loan Fee Income	131,936	131,935	134,105
(Reversal of) provision for loan losses	(1,900)	(3,200)
Net Interest and Loan Fee Income After Reversal of Provision For Loan Losses	133,836	135,135	134,105
Noninterest Income:
Service charges on deposit accounts	19,612	20,854	22,241
Merchant processing services	8,426	6,377	6,339
Securities gains	7,955
Debit card fees	6,421	6,290	6,084
Trust fees	2,875	2,686	2,732
ATM processing fees	2,610	2,411	2,397
Other service fees	2,584	2,571	2,689
Financial services commissions	639	568	695
Other noninterest income	5,506	4,817	4,690
Total Noninterest Income	56,628	46,574	47,867
Noninterest Expense:
Salaries and related benefits	51,519	51,507	52,192
Occupancy and equipment	19,430	19,017	19,394
Outsourced data processing services	9,035	8,505	8,441
Loss contingency	5,542	3
Amortization of identifiable intangibles	3,077	3,504	3,856
Professional fees	2,161	3,980	2,490
Courier service	1,732	1,952	2,329
Impairment of tax credit investments	625
Other noninterest expense	10,171	13,284	16,598
Total Noninterest Expense	103,292	101,752	105,300
Income Before Income Taxes	87,172	79,957	76,672
Provision for income taxes	37,147	21,104	17,919
Net Income	$ 50,025	$ 58,853	$ 58,753
Average Common Shares Outstanding (in shares)	26,291	25,612	25,555
Diluted Average Common Shares Outstanding (in shares)	26,419	25,678	25,577
Per Common Share Data:
Basic earnings (in dollars per share)	$ 1.90	$ 2.30	$ 2.30
Diluted earnings (in dollars per share)	1.89	2.29	2.30
Dividends paid (in dollars per share)	$ 1.57	$ 1.56	$ 1.53

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income	$ 4,160	$ 15,017	$ 15,799	$ 15,049	$ 14,453	$ 15,628	$ 14,546	$ 14,226	$ 14,578	$ 14,857	$ 14,761	$ 14,557	$ 50,025	$ 58,853	$ 58,753
Other comprehensive loss:
Changes in net unrealized gains on securities available for sale													(3,767)	(18,610)	(8,028)
Deferred tax benefit													1,585	7,825	3,375
Reclassification of gains included in net income													(7,955)
Deferred tax expense on gains included in net income													3,345
Changes in unrealized gains and losses on securities available for sale, net of tax													(6,792)	(10,785)	(4,653)
Post-retirement benefit transition obligation amortization													59	61	61
Deferred tax expense													(25)	(25)	(25)
Post-retirement benefit transition obligation amortization, net of tax													34	36	36
Total Other Comprehensive Loss													(6,758)	(10,749)	(4,617)
Total Comprehensive Income													$ 43,267	$ 48,104	$ 54,136

Consolidated Statements of Chan

Consolidated Statements of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Accumulated Deferred Compensation [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2014	25,745
Balance at Dec. 31, 2014	$ 378,132	$ 2,711	$ 5,292	$ 140,468	$ 526,603
Net income				58,753	58,753
Other comprehensive income (loss), net of tax			(4,617)		(4,617)
Exercise of stock options (in shares)	108
Exercise of stock options	$ 4,848				4,848
Tax benefit decrease upon exercise and expiration of stock options	$ (1,284)				(1,284)
Restricted stock activity (in shares)	17
Restricted stock activity	$ 874	(133)			741
Stock based compensation	$ 1,272				1,272
Stock awarded to employees (in shares)	2
Stock awarded to employees	$ 105				105
Retirement of common stock (in shares)	(344)
Retirement of common stock	$ (5,089)			(10,003)	(15,092)
Dividends				(39,124)	(39,124)
Balance (in shares) at Dec. 31, 2015	25,528
Balance at Dec. 31, 2015	$ 378,858	2,578	675	150,094	532,205
Net income				58,853	58,853
Other comprehensive income (loss), net of tax			(10,749)		(10,749)
Exercise of stock options (in shares)	499
Exercise of stock options	$ 24,031				24,031
Tax benefit decrease upon exercise and expiration of stock options	$ 394				394
Restricted stock activity (in shares)	15
Restricted stock activity	$ 1,798	(1,045)			753
Stock based compensation	$ 1,494				1,494
Stock awarded to employees (in shares)	2
Stock awarded to employees	$ 90				90
Retirement of common stock (in shares)	(137)
Retirement of common stock	$ (2,059)			(3,721)	(5,780)
Dividends				(39,924)	(39,924)
Balance (in shares) at Dec. 31, 2016	25,907
Balance at Dec. 31, 2016	$ 404,606	1,533	(10,074)	165,302	561,367
Net income				50,025	50,025
Other comprehensive income (loss), net of tax			(6,758)		$ (6,758)
Exercise of stock options (in shares)	509				509
Exercise of stock options	$ 24,583				$ 24,583
Restricted stock activity (in shares)	13
Restricted stock activity	$ 707				707
Stock based compensation	$ 1,824				1,824
Stock awarded to employees (in shares)	2
Stock awarded to employees	$ 104				104
Retirement of common stock (in shares)	(6)
Retirement of common stock	$ (90)			(224)	(314)
Dividends				(41,299)	(41,299)
Balance (in shares) at Dec. 31, 2017	26,425
Balance at Dec. 31, 2017	$ 431,734	$ 1,533	$ (16,832)	$ 173,804	$ 590,239

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities:
Net income		$ 50,025	$ 58,853	$ 58,753
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization/accretion		26,082	19,939	16,402
(Reversal of) provision for loan losses		(1,900)	(3,200)
Net amortization of deferred loan fees		(46)	(340)	(310)
Increase in interest income receivable		(2,068)	(1,316)	(780)
Life insurance premiums paid		(842)	(828)	(782)
Decrease in net deferred tax asset		27,018	4,380	830
Increase in other assets		(890)	(2,493)	(1,046)
Stock option compensation expense		1,824	1,494	1,272
Tax benefit (increase) decrease upon exercise and expiration of stock options			(394)	1,284
(Decrease) increase in income taxes payable		(6,650)	(40)	265
Decrease in interest expense payable		(31)	(52)	(86)
(Decrease) increase in other liabilities		(3,016)	2,026	(5,754)
Gain on sale of other assets		(1,004)
Gain on sale of securities		(7,955)
Write-down/net loss on sale of premises and equipment		60	30	109
Net loss/write-down (gain) on sale of foreclosed assets		147	(422)	247
Net Cash Provided by Operating Activities		80,754	77,637	70,404
Investing Activities:
Net repayments of loans		66,065	183,506	164,093
Change in payable to FDIC	[1]	(63)	(127)
Purchases of investment securities available for sale		(635,814)	(1,080,959)	(946,794)
Proceeds from sale/maturity/calls of securities available for sale		319,324	737,625	967,118
Purchases of investment securities held to maturity			(246,956)	(437,935)
Proceeds from maturity/calls of securities held to maturity		178,429	204,054	153,014
Purchases of premises and equipment		(2,720)	(1,818)	(4,474)
Net change in FHLB securities	[2]			940
Proceeds from sale of foreclosed assets		1,521	7,412	1,774
Net Cash Used in Investing Activities		(73,258)	(197,263)	(102,264)
Financing Activities:
Net change in deposits		122,872	164,082	191,476
Net change in short-term borrowings and FHLB advances		(607)	6,050	(56,756)
Exercise of stock options/issuance of shares		24,583	24,031	4,848
Taxes paid by withholding shares for tax purposes			(356)	(357)
Tax benefit increase (decrease) upon expiration/exercise of stock options			394	(1,284)
Retirement of common stock		(314)	(5,424)	(14,735)
Common stock dividends paid		(41,299)	(39,924)	(39,124)
Net Cash Provided by Financing Activities		105,235	148,853	84,068
Net Change In Cash and Due from Banks		112,731	29,227	52,208
Cash and Due from Banks at Beginning of Period		462,271	433,044	380,836
Cash and Due from Banks at End of Period		575,002	462,271	433,044
Supplemental disclosure of noncash activities:
Loan collateral transferred to other real estate owned			821	4,911
Securities purchases pending settlement				2,885
Supplemental disclosure of cash flow activities:
Interest paid for the period		1,931	2,202	2,533
Income tax payments for the period		$ 17,351	$ 19,264	$ 17,666
[1]	Federal Deposit Insurance Corporation ("FDIC")
[2]	Federal Home Loan Bank ("FHLB")

Note 1 - Business and Accountin

Note 1 - Business and Accounting Policies	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Note 1: Westamerica Bancorporation, a registered bank holding company (the “Company”), provides a full range of banking services to corporate and individual customers in Northern and Central California through its wholly-owned subsidiary bank, Westamerica Bank (the “Bank”). The Bank is subject to competition from both financial and nonfinancial institutions and to the regulations of certain agencies and undergoes periodic examinations by those regulatory authorities. All of the financial service operations are considered by management to be aggregated in one The Company has evaluated events and transactions subsequent to the balance sheet date. Based on this evaluation, the Company is not Summary of Significant Accounting Policies The consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America. The following is a summary of significant policies used in the preparation of the accompanying financial statements. Accounting Estimates. Certain accounting policies underlying the preparation of these financial statements require Management to make estimates and judgments about future economic and market conditions. These estimates and judgments may 2018 Principles of Consolidation. The consolidated financial statements include the accounts of the Company and all the Company’s subsidiaries. Significant intercompany transactions have been eliminated in consolidation. The Company does not Cash. Cash includes Due From Banks balances which are readily convertible to known amounts of cash and are generally 90 Securities. Investment securities consist of debt securities of the U.S. Treasury, government sponsored entities, states, counties, municipalities, corporations, agency and non-agency mortgage-backed securities, asset-backed securities and equity securities. Securities transactions are recorded on a trade date basis. The Company classifies its debt and marketable equity securities in one three not The Company utilizes third 1 2 third one third third not 3 A decline in the market value of any available for sale or held to maturity security below amortized cost that is deemed other than temporary results in a charge to earnings and the establishment of a new cost basis for the security. Unrealized investment securities losses are evaluated at least quarterly to determine whether such declines in value should be considered “other than temporary” and therefore be subject to immediate loss recognition in income. Although these evaluations involve significant judgment, an unrealized loss in the fair value of a debt security is generally deemed to be temporary when the fair value of the security is below the carrying value primarily due to changes in risk-free interest rates, there has not not not not may The Company follows the guidance issued by the Board of Governors of the Federal Reserve System, “Investing in Securities without Reliance on Nationally Recognized Statistical Rating Agencies” (SR 12 15 Purchase premiums are amortized and purchase discounts are accreted over the estimated life of the related investment security as an adjustment to yield using the effective interest method. Unamortized premiums, unaccreted discounts, and early payment premiums are recognized as a component of gain or loss on sale upon disposition of the related security. Interest and dividend income are recognized when earned. Realized gains and losses from the sale of available for sale securities are included in earnings using the specific identification method. Nonmarketable Equity Securities. Nonmarketable equity securities include securities that are not Loans. Loans are stated at the principal amount outstanding, net of unearned discount and unamortized deferred fees and costs. Interest is accrued daily on the outstanding principal balances. Loans which are more than 90 120 The Company evaluates all classified loans and nonaccrual loans with outstanding principal balances in excess of $500 310 40, not Nonrefundable fees and certain costs associated with originating or acquiring loans are deferred and amortized as an adjustment to interest income over the contractual loan lives. Upon prepayment, unamortized loan fees, net of costs, are immediately recognized in interest income. Other fees, including those collected upon principal prepayments, are included in interest income when received. Loans held for sale are identified upon origination and are reported at the lower of cost or market value on an aggregate loan basis. Purchased Loans. Purchased loans are recorded at estimated fair value on the date of purchase. Impaired purchased loans are accounted for under FASB ASC 310 30, not may 310 30. 310 30 not 310 30 Covered Loans. Loans covered under loss-sharing or similar credit protection agreements with the FDIC are reported in loans exclusive of the expected reimbursement cash flows from the FDIC. Covered loans are initially recorded at fair value at the acquisition date. Subsequent decreases in the amount expected to be collected results in a provision for loan losses and a corresponding increase in the estimated FDIC reimbursement, with the estimated net loss impacting earnings. Interest previously accrued on covered loans placed on nonaccrual status is charged against interest income, net of estimated FDIC reimbursements of such accrued interest. The FDIC reimburses the Company up to 80% 90 Allowance for Credit Losses. The Company extends loans to commercial and consumer customers primarily in Northern and Central California. These lending activities expose the Company to the risk borrowers will default, causing loan losses. The Company’s lending activities are exposed to various qualitative risks. All loan segments are exposed to risks inherent in the economy and market conditions. Significant risk characteristics related to the commercial loan segment include the borrowers’ business performance and financial condition, and the value of collateral for secured loans. Significant risk characteristics related to the commercial real estate segment include the borrowers’ business performance and the value of properties collateralizing the loans. Significant risk characteristics related to the construction loan segment include the borrowers’ performance in successfully developing the real estate into the intended purpose and the value of the property collateralizing the loans. Significant risk characteristics related to the residential real estate segment include the borrowers’ financial wherewithal to service the mortgages and the value of the property collateralizing the loans. Significant risk characteristics related to the consumer loan segment include the financial condition of the borrowers and the value of collateral securing the loans. The preparation of these financial statements requires Management to estimate the amount of probable incurred losses inherent in the loan portfolio and establish an allowance for credit losses. The allowance for credit losses is established by assessing a provision for loan losses against the Company’s earnings. In estimating credit losses, Management must exercise significant judgment in evaluating information deemed relevant, such as financial information regarding individual borrowers, overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions and other information. The amount of ultimate losses on the loan portfolio can vary from the estimated amounts. Management follows a systematic methodology to estimate loss potential in an effort to reduce the differences between estimated and actual losses. The allowance for credit losses is established through provisions for credit losses charged to income. Losses on loans, including impaired loans, are charged to the allowance for loan losses when all or a portion of the recorded amount of a loan is deemed to be uncollectible. Recoveries of loans previously charged off are credited to the allowance when realized. The Company’s allowance for credit losses is maintained at a level considered adequate to provide for losses that can be estimated based upon specific and general conditions. These include conditions unique to individual borrowers, as well as overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions, FDIC loss-sharing or similar credit protection agreements and other factors. A portion of the allowance is specifically allocated to impaired loans whose full collectability is uncertain. Such allocations are determined by Management based on loan-by-loan analyses. The Company evaluates all classified loans and nonaccrual loans with outstanding principal balances in excess of $500 second not not not not Liability for Off-Balance Sheet Credit Exposures. A liability for off-balance sheet credit exposures is established through expense recognition. Off-balance sheet credit exposures relate to letters of credit and unfunded loan commitments for commercial, construction and consumer loans. Historical credit loss factors for commercial, construction and consumer loans are applied to the amount of these off-balance sheet credit exposures to estimate inherent losses. Other Real Estate Owned. Other real estate owned is comprised of property acquired through foreclosure proceedings, acceptances of deeds-in-lieu of foreclosure and, if applicable, vacated bank properties. Losses recognized at the time of acquiring property in full or partial satisfaction of debt are charged against the allowance for credit losses. Other real estate owned is recorded at the fair value of the collateral, generally based upon an independent property appraisal, less estimated disposition costs. Losses incurred subsequent to acquisition due to any decline in annual independent property appraisals are recognized as noninterest expense. Routine holding costs, such as property taxes, insurance and maintenance, and losses from sales and dispositions, are recognized as noninterest expense. Covered Other Real Estate Owned. Other real estate owned covered under loss-sharing agreements with the FDIC is reported exclusive of expected reimbursement cash flows from the FDIC. Upon transferring covered loan collateral to covered other real estate owned status, the covered loan collateral is recorded at fair value, generally based upon an independent property appraisal, less estimated disposition costs with losses charged against acquisition date fair value discounts; the amount of losses exceeding acquisition date fair value discounts are recognized as noninterest expense inclusive of expected reimbursement cash flows from the FDIC. Subsequent losses incurred due to any decline in annual independent property appraisal valuations are recognized as noninterest expense inclusive of expected reimbursement cash flows from the FDIC. Premises and Equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed substantially on the straight-line method over the estimated useful life of each type of asset. Estimated useful lives of premises and equipment range from 20 50 3 20 Revenue Recognition. The Company recognizes revenue as it is earned based on contractual terms, as transactions occur, or as services are provided and collectability is reasonably assured. In certain circumstances, noninterest income is reported net of associated expenses that are directly related to variable volume-based sales or revenue sharing arrangements or when the Company acts on an agency basis for others. Life Insurance Cash Surrender Value. The Company has purchased life insurance policies on certain directors and officers as well as acquired such assets as part of the acquisition of other banks. Company owned life insurance is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. These assets are included in other assets on the consolidated balance sheets. Intangible Assets. Intangible assets are comprised of goodwill, core deposit intangibles and other identifiable intangibles acquired in business combinations. Intangible assets with definite useful lives are amortized on an accelerated basis over their respective estimated useful lives not 15 may not not first 2011 08, Testing for Goodwill Impairment. first Impairment of Long-Lived Assets. The Company reviews its long-lived and certain intangible assets for impairment whenever events or changes indicate that the carrying amount of an asset may not Income Taxes. The Company and its subsidiaries file consolidated tax returns. The Company accounts for income taxes in accordance with FASB ASC 740, two not. not fifty Stock Options. The Company applies FASB ASC 718 no Extinguishment of Debt. Gains and losses, including fees, incurred in connection with the early extinguishment of debt are charged to current earnings as reductions in noninterest income. Postretirement Benefits. The Company uses an actuarial-based accrual method of accounting for post-retirement benefits. Other. Securities and other property held by the Bank in a fiduciary or agency capacity are not not Recently Adopted Accounting Standards In 2017, FASB Accounting Standards Update (ASU) 2016 09, Improvements to Employee Share-Based Payment Accounting, March 30, 2016. 1 2 3 January 1, 2017, 2017, 509 $1,667 2017 $698 2016 09. Recently Issued Accounting Standards FASB ASU 2014 09 Revenue (Topic 606 May 2014. not 606 not Approximately 73% not January 1, 2018. FASB ASU 2016 01 Financial Instruments – Overall (Subtopic 825 10 January 2016. The Company was required to adopt the ASU provisions on January 1, 2018, not December 31, 2017, $2000 FASB ASU 2016 02, Leases (Topic 842 February 25, 2016. The Company will be required to adopt the ASU provisions January 1, 2019, December 31, 2017, 58 $17.5 not FASB ASU 2016 13, Financial Instruments – Credit Losses (Topic 326 June 16, 2016. The Company will be required to adopt the ASU provisions on January 1, 2020. FASB ASU 2017 08 Receivables – Non-Refundable Fees and Other Costs (Subtopic 310 20 March 2017. not The Company will be required to adopt the ASU provisions on January 1, 2019. FASB ASU 2017 12 Derivatives and Hedging (Topic 815 August 2017. one The Company will be required to adopt the ASU provisions January 1, 2019. not may one

Note 2 - Investment Securities

Note 2 - Investment Securities	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]	Note 2: An analysis of the amortized cost, gross unrealized gains and losses accumulated in other comprehensive income, and fair value of the available for sale investment securities portfolio follows: Investment Securities Available for Sale Amortized Gross Gross Fair (In thousands) Securities of U.S. Government sponsored entities $ 122,285 $ 1 $ (2,967 ) $ 119,319 Agency residential mortgage-backed securities (MBS) 787,679 522 (20,495 ) 767,706 Non-agency residential MBS 153 1 - 154 Agency commercial MBS 2,244 - (25 ) 2,219 Securities of U.S. Government entities 1,612 - (22 ) 1,590 Obligations of states and political subdivisions 182,907 3,796 (1,482 ) 185,221 Corporate securities 1,123,671 1,104 (9,277 ) 1,115,498 Other securities 2,000 - (200 ) 1,800 Total $ 2,222,551 $ 5,424 $ (34,468 ) $ 2,193,507 An analysis of the amortized cost, gross unrecognized gains and losses, and fair value of the held to maturity investment securities portfolio follows: Investment Securities Held to Maturity Amortized Gross Gross Fair (In thousands) Agency residential MBS $ 545,883 $ 606 $ (9,850 ) $ 536,639 Non-agency residential MBS 4,462 70 - 4,532 Agency commercial MBS 9,041 - (66 ) 8,975 Obligations of states and political subdivisions 599,478 7,736 (2,018 ) 605,196 Total $ 1,158,864 $ 8,412 $ (11,934 ) $ 1,155,342 An analysis of the amortized cost, gross unrealized gains and losses accumulated in other comprehensive income, and fair value of the available for sale investment securities portfolio follows: Investment Securities Available for Sale Amortized Gross Gross Value (In thousands) Securities of U.S. Government sponsored entities $ 141,599 $ 35 $ (2,974 ) $ 138,660 Agency residential MBS 711,623 921 (21,045 ) 691,499 Non-agency residential MBS 272 - (1 ) 271 Securities of U.S. Government entities 2,041 - (16 ) 2,025 Obligations of states and political subdivisions 182,230 5,107 (3,926 ) 183,411 Asset-backed securities 696 - (1 ) 695 FHLMC (1) (2) 749 10,120 - 10,869 Corporate securities 866,835 1,690 (7,668 ) 860,857 Other securities 2,034 621 (184 ) 2,471 Total $ 1,908,079 $ 18,494 $ (35,815 ) $ 1,890,758 ( 1 ( 2 An analysis of the amortized cost, gross unrecognized gains and losses, and fair value of the held to maturity investment securities portfolio follows: Investment Securities Held to Maturity Amortized Gross Gross Fair (In thousands) Securities of U.S. Government sponsored entities $ 581 $ 1 $ - $ 582 Agency residential MBS 668,235 1,122 (8,602 ) 660,755 Non-agency residential MBS 5,370 76 - 5,446 Agency commercial MBS 9,332 11 (143 ) 9,200 Obligations of states and political subdivisions 662,794 6,031 (4,067 ) 664,758 Total $ 1,346,312 $ 7,241 $ (12,812 ) $ 1,340,741 During the quarter ending December 31, 2017, $8,704 $7,955 The amortized cost and fair value of investment securities by contractual maturity are shown in the following tables at the dates indicated: At December 31, 2017 Securities Available Securities Held Amortized Fair Amortized Fair (In thousands) Maturity in years: 1 year or less $ 193,337 $ 193,385 $ 50,295 $ 51,105 Over 1 to 5 years 1,031,807 1,023,047 269,050 269,471 Over 5 to 10 years 159,266 160,042 277,170 281,546 Over 10 years 46,065 45,154 2,963 3,074 Subtotal 1,430,475 1,421,628 599,478 605,196 MBS 790,076 770,079 559,386 550,146 Other securities 2,000 1,800 - - Total $ 2,222,551 $ 2,193,507 $ 1,158,864 $ 1,155,342 At December 31, 2016 Securities Available Securities Held Amortized Fair Amortized Fair (In thousands) Maturity in years: 1 year or less $ 154,693 $ 154,835 $ 14,961 $ 15,639 Over 1 to 5 years 750,834 745,219 292,024 292,062 Over 5 to 10 years 238,077 239,153 318,580 319,587 Over 10 years 47,756 44,416 37,810 38,052 Subtotal 1,191,360 1,183,623 663,375 665,340 MBS 713,936 693,795 682,937 675,401 Other securities 2,783 13,340 - - Total $ 1,908,079 $ 1,890,758 $ 1,346,312 $ 1,340,741 Expected maturities of mortgage-related securities can differ from contractual maturities because borrowers have the right to call or prepay obligations with or without call or prepayment penalties. In addition, such factors as prepayments and interest rates may December 31, 2017 December 31, 2016, no An analysis of the gross unrealized losses of the available for sale investment securities portfolio follows: Investment Securities Available for Sale At December 31, 2017 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Value Unrealized Investment Fair Value Unrealized Investment Fair Value Unrealized ($ in thousands) Securities of U.S. Government sponsored entities 1 $ 996 $ ( 2 ) 8 $ 117,252 $ (2,965 ) 9 $ 118,248 $ ( 2,967 ) Agency residential MBS 7 238,554 (1,501 ) 51 516,711 (18,994 ) 58 755,265 (20,495 ) Non-agency residential MBS 1 1 - - - - 1 1 - Agency commercial MBS 2 2,219 (25 ) - - - 2 2,219 (25 ) Securities of U.S. Government entities - - - 3 1,590 (22 ) 3 1,590 (22 ) Obligations of states and political subdivisions 50 21,453 (228 ) 35 52,071 (1,254 ) 85 73,524 (1,482 ) Corporate securities 64 571,112 (4,047 ) 38 282,924 (5,230 ) 102 854,036 (9,277 ) Other securities - - - 1 1,800 (200 ) 1 1,800 (200 ) Total 125 $ 834,335 $ (5,803 ) 136 $ 972,348 $ (28,665 ) 261 $ 1,806,683 $ (34,468 ) An analysis of gross unrecognized losses of the held to maturity investment securities portfolio follows: Investment Securities Held to Maturity At December 31, 2017 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Value Unrecognized Investment Fair Value Unrecognized Investment Fair Value Unrecognized ($ in thousands) Agency residential MBS 15 $ 30,218 $ (201 ) 65 $ 479,775 $ (9,649 ) 80 $ 509,993 $ (9,850 ) Agency commercial MBS 1 1,913 (4 ) 1 7,062 (62 ) 2 8,975 (66 ) Obligations of states and political subdivisions 146 131,032 (553 ) 59 58,979 (1,465 ) 205 190,011 (2,018 ) Total 162 $ 163,163 $ (758 ) 125 $ 545,816 $ (11,176 ) 287 $ 708,979 $ (11,934 ) The unrealized losses on the Company’s investment securities were caused by market conditions for these types of investments, particularly changes in risk-free interest rates. The Company evaluates securities on a quarterly basis including changes in security ratings issued by rating agencies, changes in the financial condition of the issuer, and, for mortgage-backed and asset-backed securities, delinquency and loss information with respect to the underlying collateral, changes in the levels of subordination for the Company’s particular position within the repayment structure and remaining credit enhancement as compared to expected credit losses of the security. Substantially all of these securities continue to be investment grade rated by a major rating agency. In addition to monitoring credit rating agency evaluations, Management performs its own evaluations regarding the credit worthiness of the issuer or the securitized assets underlying asset backed securities. The Company does not not not not December 31, 2017. The fair values of the investment securities could decline in the future if the general economy deteriorates, inflation increases, credit ratings decline, the issuer’s financial condition deteriorates, or the liquidity for securities declines. As a result, other than temporary impairments may As of December 31, 2017, $715,774 December 31, 2016, $768,845 An analysis of gross unrealized losses of investment securities available for sale follows: Investment Securities Available for Sale At December 31, 2016 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Unrealized Investment Fair Unrealized Investment Fair Unrealized Positions Value Losses Positions Value Losses Positions Value Losses ($ in thousands) Securities of U.S. Government sponsored entities 8 $ 117,227 $ (2,974 ) - $ - $ - 8 $ 117,227 $ (2,974 ) Agency residential MBS 21 524,269 (16,494 ) 28 122,901 (4,551 ) 49 647,170 (21,045 ) Non-agency residential MBS 2 246 (1 ) - - - 2 246 (1 ) Securities of U.S. Government entities 2 1,253 (9 ) 1 772 (7 ) 3 2,025 (16 ) Obligations of states and political subdivisions 43 57,989 (3,905 ) 3 1,117 (21 ) 46 59,106 (3,926 ) Asset-backed securities - - - 1 695 (1 ) 1 695 (1 ) Corporate securities 53 385,175 (6,551 ) 27 96,145 (1,117 ) 80 481,320 (7,668 ) Other securities - - - 1 1,816 (184 ) 1 1,816 (184 ) Total 129 $ 1,086,159 $ (29,934 ) 61 $ 223,446 $ (5,881 ) 190 $ 1,309,605 $ (35,815 ) An analysis of gross unrecognized losses of investment securities held to maturity follows: Investment Securities Held to Maturity At December 31, 2016 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Unrecognized Investment Fair Unrecognized Investment Fair Unrecognized Positions Value Losses Positions Value Losses Positions Value Losses ($ in thousands) Agency residential MBS 66 $ 569,876 $ (8,285 ) 3 $ 10,480 $ (317 ) 69 $ 580,356 $ (8,602 ) Agency commercial MBS - - - 1 7,214 (143 ) 1 7,214 (143 ) Obligations of states and political subdivisions 295 272,496 (3,710 ) 12 13,126 (357 ) 307 285,622 (4,067 ) Total 361 $ 842,372 $ (11,995 ) 16 $ 30,820 $ (817 ) 377 $ 873,192 $ (12,812 ) The following table provides information about the amount of interest income earned on investment securities which is fully taxable and which is exempt from regular federal income tax: For the Years Ended December 31, 2017 2016 2015 (In thousands) Taxable $ 51,445 $ 42,718 $ 34,472 Tax-exempt from regular federal income tax 20,651 22,194 23,616 Total interest income from investment securities $ 72,096 $ 64,912 $ 58,088

Note 3 - Loans and Allowance fo

Note 3 - Loans and Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	Note 3: A summary of the major categories of loans outstanding is shown in the following tables at the dates indicated. At December 31, 2017 2016 (In thousands) Commercial $ 335,996 $ 354,697 Commercial Real Estate 568,584 542,171 Construction 5,649 2,555 Residential Real Estate 65,183 87,724 Consumer Installment & Other 312,570 365,564 Total $ 1,287,982 $ 1,352,711 Total loans outstanding reported above include loans purchased from the FDIC of $83,478 $121,210 December 31, 2017 December 31, 2016, Changes in the accretable yield for purchased loans were as follows: For the Years Ended December 31, 2017 2016 Accretable yield: (In thousands) Balance at the beginning of the period $ 1,237 $ 1,259 Reclassification from nonaccretable difference 1,852 3,912 Accretion (2,351 ) (3,934 ) Balance at the end of the period $ 738 $ 1,237 Accretion $ (2,351 ) $ (3,934 ) Change in FDIC indemnification 192 1,053 (Increase) in interest income $ (2,159 ) $ (2,881 ) The following summarizes activity in the allowance for loan losses: Allowance for Loan Losses Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Additions: (Reversal) provision (382 ) 431 (1,716 ) (335 ) 1,271 (1,169 ) (1,900 ) Deductions: Chargeoffs (961 ) - - - (4,957 ) - (5,918 ) Recoveries 762 88 1,899 - 2,124 - 4,873 Net loan (losses) recoveries (199 ) 88 1,899 - (2,833 ) - (1,045 ) Total allowance for loan losses $ 7,746 $ 3,849 $ 335 $ 995 $ 6,418 $ 3,666 $ 23,009 Allowance for Credit Losses Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 9,559 $ 4,212 $ 235 $ 1,801 $ 8,001 $ 5,963 $ 29,771 Additions: (Reversal) provision (3,237 ) (1,436 ) (83 ) (471 ) 3,155 (1,128 ) (3,200 ) Deductions: Chargeoffs (2,023 ) - - - (4,749 ) - (6,772 ) Recoveries 4,028 554 - - 1,573 - 6,155 Net loan recoveries (losses) 2,005 554 - - (3,176 ) - (617 ) Total allowance for loan losses $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Allowance for Loan Losses For the Year Ended December 31, 2015 Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 5,460 $ 4,245 $ 654 $ 2,241 $ 9,827 $ 9,058 $ 31,485 Additions: Provision (reversal) 3,681 126 (33 ) (440 ) (239 ) (3,095 ) - Deductions: Chargeoffs (756 ) (449 ) (431 ) - (3,493 ) - (5,129 ) Recoveries 1,174 290 45 - 1,906 - 3,415 Net loan recoveries (losses) 418 (159 ) (386 ) - (1,587 ) - (1,714 ) Total allowance for loan losses $ 9,559 $ 4,212 $ 235 $ 1,801 $ 8,001 $ 5,963 $ 29,771 The allowance for loan losses and recorded investment in loans evaluated for impairment were as follows: Allowance for Loan Losses and Recorded Investment in Loans Evaluated for Impairment At December 31, 2017 Commercial Commercial Construction Residential Real Estate Consumer Installment and Other Unallocated Total (In thousands) Allowance for loan losses: Individually evaluated for impairment $ 4,814 $ 171 $ - $ - $ - $ - $ 4,985 Collectively evaluated for impairment 2,932 3,678 335 995 6,418 3,666 18,024 Purchased loans with evidence of credit deterioration - - - - - - - Total $ 7,746 $ 3,849 $ 335 $ 995 $ 6,418 $ 3,666 $ 23,009 Carrying value of loans: Individually evaluated for impairment $ 10,675 $ 14,234 $ - $ 208 $ - $ - $ 25,117 Collectively evaluated for impairment 325,291 553,769 5,649 64,975 312,406 - 1,262,090 Purchased loans with evidence of credit deterioration 30 581 - - 164 - 775 Total $ 335,996 $ 568,584 $ 5,649 $ 65,183 $ 312,570 $ - $ 1,287,982 Allowance for Loan Losses and Recorded Investment in Loans Evaluated for Impairment At December 31, 2016 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Unallocated Total (In thousands) Allowance for loan losses: Individually evaluated for impairment $ 5,048 $ - $ - $ - $ - $ - $ 5,048 Collectively evaluated for impairment 3,279 3,330 152 1,330 7,980 4,835 20,906 Purchased loans with evidence of credit deterioration - - - - - - - Total $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Carrying value of loans: Individually evaluated for impairment $ 11,174 $ 12,706 $ - $ 835 $ - $ - $ 24,715 Collectively evaluated for impairment 343,494 528,957 2,555 86,889 365,236 - 1,327,131 Purchased loans with evidence of credit deterioration 29 508 - - 328 - 865 Total $ 354,697 $ 542,171 $ 2,555 $ 87,724 $ 365,564 $ - $ 1,352,711 The Bank’s customers are small businesses, professionals and consumers. Given the scale of these borrowers, corporate credit rating agencies do not The following summarizes the credit risk profile by internally assigned grade: Credit Risk Profile by Internally Assigned Grade At December 31, 2017 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Total (In thousands) Grade: Pass $ 324,185 $ 548,853 $ 5,649 $ 62,253 $ 310,429 $ 1,251,369 Substandard 11,811 19,731 - 2,930 1,370 35,842 Doubtful - - - - 1 1 Loss - - - - 770 770 Total $ 335,996 $ 568,584 $ 5,649 $ 65,183 $ 312,570 $ 1,287,982 Credit risk profile reflects internally assigned grade of purchased covered loans without regard to FDIC indemnification. Credit Risk Profile by Internally Assigned Grade At December 31, 2016 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Total (In thousands) Grade: Pass $ 340,973 $ 515,045 $ 2,555 $ 84,384 $ 362,597 $ 1,305,554 Substandard 13,724 25,830 - 3,340 2,477 45,371 Doubtful - 1,296 - - 10 1,306 Loss - - - - 480 480 Total $ 354,697 $ 542,171 $ 2,555 $ 87,724 $ 365,564 $ 1,352,711 Credit risk profile reflects internally assigned grade of purchased covered loans without regard to FDIC indemnification. The following tables summarize loans by delinquency and nonaccrual status: Summary of Loans by Delinquency and Nonaccrual Status Current and Accruing 30-59 Days Past Due and Accruing 60-89 Days Past Due and Accruing Past Due 90 Days or More and Accruing Nonaccrual Total Loans (In thousands) Commercial $ 334,908 $ 627 $ 164 $ - $ 297 $ 335,996 Commercial real estate 561,883 1,143 125 - 5,433 568,584 Construction 5,649 - - - - 5,649 Residential real estate 65,183 - - - - 65,183 Consumer installment and other 307,445 3,321 1,077 531 196 312,570 Total $ 1,275,068 $ 5,091 $ 1,366 $ 531 $ 5,926 $ 1,287,982 Summary of Loans by Delinquency and Nonaccrual Status Current and Accruing 30-59 Days Past Due and Accruing 60-89 Days Past Due and Accruing Past Due 90 Days or More and Accruing Nonaccrual Total Loans (In thousands) Commercial $ 353,497 $ 966 $ 40 $ - $ 194 $ 354,697 Commercial real estate 533,377 1,460 445 - 6,889 542,171 Construction 2,329 226 - - - 2,555 Residential real estate 86,098 528 37 - 1,061 87,724 Consumer installment and other 360,549 3,288 989 497 241 365,564 Total $ 1,335,850 $ 6,468 $ 1,511 $ 497 $ 8,385 $ 1,352,711 There were no December 31, 2017 December 31, 2016. The following summarizes impaired loans: Impaired Loans 2017 2016 Recorded Unpaid Related Recorded Unpaid Related (In thousands) With no related allowance recorded: Commercial $ 1,212 $ 1,271 $ - $ 1,234 $ 1,303 $ - Commercial real estate 13,169 14,985 - 13,233 15,610 - Residential real estate 208 239 - 1,279 1,309 - Consumer installment and other 360 466 - 569 675 - Total with no related allowance recorded 14,949 16,961 - 16,315 18,897 - With an allowance recorded: Commercial 9,764 9,764 4,814 10,163 10,172 5,048 Commercial real estate 1,790 1,792 171 - - - Total with an allowance recorded 11,554 11,556 4,985 10,163 10,172 5,048 Total $ 26,503 $ 28,517 $ 4,985 $ 26,478 $ 29,069 $ 5,048 Impaired loans include troubled debt restructured loans. Impaired loans at December 31, 2017, $12,081 $4,285 December 31, 2016, $12,381 $5,302 Impaired Loans 2017 2016 2015 Average Recognized Average Recognized Average Recognized (In thousands) Commercial $ 11,156 $ 508 $ 12,923 $ 512 $ 12,631 $ 584 Commercial real estate 14,806 884 16,701 725 20,307 674 Construction - - 102 - 263 - Residential real estate 423 17 746 19 643 31 Consumer installment and other 415 20 473 25 739 25 Total $ 26,800 $ 1,429 $ 30,945 $ 1,281 $ 34,583 $ 1,314 The following tables provide information on troubled debt restructurings: Troubled Debt Restructurings Period-End ($ in thousands) Commercial 7 $ 2,393 $ 1,085 $ 43 Commercial real estate 10 11,528 10,788 - Residential real estate 1 241 208 - Total 18 $ 14,162 $ 12,081 $ 43 Troubled Debt Restructurings Period-End ($ in thousands) Commercial 7 $ 2,719 $ 1,489 $ 113 Commercial real estate 10 11,257 10,673 - Residential real estate 1 241 219 - Total 18 $ 14,217 $ 12,381 $ 113 Troubled Debt Restructurings Period-End ($ in thousands) Commercial 6 $ 3,138 $ 2,802 $ 194 Commercial real estate 10 12,927 12,684 - Residential real estate 1 242 226 - Total 17 $ 16,307 $ 15,712 $ 194 During the year ended December 31, 2017, four $699 four 2017 During the year ended December 31, 2016, four $4,731 four 2016 three one During the year ended December 31, 2015, ten $11,026 2015 four six During the year ended December 31, 2017, one $58 no December 31, 2016 2015. December 31, 2017, 2016 2015, no 12 ninety There were no December 31, 2017 December 31, 2016. There were no December 31, 2017 December 31, 2016. At December 31, 2017 2016, $1,426 $1,905 $3,095 $1,816 0 $196 December 31, 2017. no December 31, 2016.

Note 4 - Concentration of Credi

Note 4 - Concentration of Credit Risk	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Concentration Risk Disclosure [Text Block]	Note 4: Under the California Financial Code, credit extended to any one one not not 15 not 25 December 31, 2017, not one December 31, 2017, 40 $5 3, $53,874 $57,721 December 31, 2017 December 31, 2016, no 75% no 80% December 31, 2017, 70 $5

Note 5 - Premises, Equipment an

Note 5 - Premises, Equipment and Other Assets	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Other Assets Disclosure [Text Block]	Note 5: Premises and equipment consisted of the following: At December 31, Cost Accumulated Depreciation and Amortization Net Book Value (In thousands) 2017 Land $ 11,796 $ - $ 11,796 Building and improvements 41,641 (26,249 ) 15,392 Leasehold improvements 5,817 (4,790 ) 1,027 Furniture and equipment 22,284 (15,198 ) 7,086 Total $ 81,538 $ (46,237 ) $ 35,301 2016 Land $ 11,896 $ - $ 11,896 Building and improvements 40,992 (25,180 ) 15,812 Leasehold improvements 5,922 (4,599 ) 1,323 Furniture and equipment 21,874 (14,339 ) 7,535 Total $ 80,684 $ (44,118 ) $ 36,566 Depreciation and amortization of premises and equipment included in noninterest expense amounted to $3,925 2017, $3,959 2016 $3,523 2015. Other assets consisted of the following: At December 31, 2017 2016 (In thousands) Cost method equity investments: Federal Reserve Bank stock (1) $ 14,069 $ 14,069 Other investments 158 201 Total cost method equity investments 14,227 14,270 Life insurance cash surrender value 54,101 51,535 Net deferred tax asset 33,112 55,417 Limited partnership investments 10,119 12,591 Interest receivable 23,557 21,489 Prepaid assets 4,906 4,825 Other assets 18,428 11,597 Total other assets $ 158,450 $ 171,724 ( 1 six The Company invests in flow-through limited liability entities that manage or invest in affordable housing projects that qualify for low-income housing tax credits. At December 31, 2017, $10,119 $2,299 December 31, 2016, $12,591 $2,299 December 31, 2017, $2,299 $722 2020, $131 2023, $90 2024 $1,356 2025 The amounts recognized in net income for these investments include: For the Years Ended December 31, 2017 2016 2015 (In thousands) Investment loss included in pre-tax income $ 1,800 $ 2,475 $ 2,850 Valuation impairment included in pre-tax income 625 - - Tax credits recognized in provision for income taxes 1,850 2,286 2,650 The $625 2017 2017.

Note 6 - Goodwill and Identifia

Note 6 - Goodwill and Identifiable Intangible Assets	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Goodwill and Intangible Assets Disclosure [Text Block]	Note 6: The Company has recorded goodwill and other identifiable intangibles associated with purchase business combinations. Goodwill is not not December 31, 2017, 2016 2015. December 31, 2017, 2016 2015 no The carrying values of goodwill were: At December 31, 2017 2016 (In thousands) Goodwill $ 121,673 $ 121,673 The gross carrying amount of identifiable intangible assets and accumulated amortization was: At December 31, 2017 2016 Gross Gross (In thousands) Core Deposit Intangibles $ 56,808 $ (52,987 ) $ 56,808 $ (50,074 ) Merchant Draft Processing Intangible 10,300 (10,271 ) 10,300 (10,107 ) Total Identifiable Intangible Assets $ 67,108 $ (63,258 ) $ 67,108 $ (60,181 ) As of December 31, 2017, Merchant (In thousands) For the Year Ended December 31, 2017 (actual) $ 2,913 $ 164 $ 3,077 Estimate for the Year Ended December 31, 2018 1,892 29 1,921 2019 538 - 538 2020 287 - 287 2021 269 - 269 2022 252 - 252

Note 7 - Deposits and Borrowed

Note 7 - Deposits and Borrowed Funds	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Deposits and Borrowed Funds [Text Block]	Note 7: The following table provides additional detail regarding deposits. Deposits At December 31, 2017 2016 (In thousands) Noninterest-bearing $ 2,197,526 $ 2,089,443 Interest-bearing: Transaction 904,245 865,701 Savings 1,494,024 1,493,427 Time deposits less than $100 thousand 117,848 133,712 Time deposits $100 thousand through $250 thousand 76,578 84,925 Time deposits more than $250 thousand 37,392 37,533 Total deposits $ 4,827,613 $ 4,704,741 Demand deposit overdrafts of $2,786 $2,679 December 31, 2017 2016, $100 $415 2017, $509 2016 $687 2015. The following table provides additional detail regarding short-term borrowed funds. Repurchase Agreements (Sweep) Remaining Contractual Maturity of the Agreements At December 31, 2017 2016 Repurchase agreements: (In thousands) Collateral securing borrowings: Securities of U.S. Government sponsored entities $ 74,173 $ 74,031 Agency residential MBS 58,251 63,277 Corporate securities 105,113 90,554 Total collateral carrying value $ 237,537 $ 227,862 Total short-term borrowed funds $ 58,471 $ 59,078 For the Years Ended December 31, 2017 2016 Highest Balance at Any Month-end (In thousands) Securities sold under repurchase agreements $ 82,126 $ 74,815

Note 8 - Shareholders' Equity

Note 8 - Shareholders' Equity	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Stockholders' Equity Note Disclosure [Text Block]	Note 8: The Company grants stock options and restricted performance shares to employees in exchange for employee services, pursuant to the shareholder-approved 1995 2012. three ten three three The following table summarizes information about stock options granted under the Plan as of December 31, 2017. December 31, 2017 December 31, 2017 $59.55 Options Outstanding Options Exercisable At December 31, 2017 For the Year Ended December 31, 2017 At December 31, 2017 For the Year Ended December 31, 2017 Range of Exercise Price Number Outstanding Aggregate Intrinsic Value Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number Exercisable Aggregate Intrinsic Value Weighted Average Remaining Contractual Life Weighted Average Exercise Price (In thousands) (Years) (In thousands) (Years) $40 - 45 400 $ 6,798 7.5 $ 43 105 $ 1,751 6.9 $ 43 45 - 50 22 305 4.1 46 22 305 4.1 46 50 - 55 310 2,588 1.9 51 310 2,588 1.9 51 55 - 60 298 725 8.3 57 32 94 2.1 57 $40 - 60 1,030 $ 10,416 6.0 49 469 $ 4,738 3.1 49 The Company applies the Roll-Geske option pricing model (Modified Roll) to determine grant date fair value of stock option grants. This model modifies the Black-Scholes Model to take into account dividends and American options. During the twelve December 31, 2017, 2016 2015, 266 325 343 For the Years Ended December 31, 2017 2016 2015 Expected volatility (1) 20 % 22 % 20 % Expected life in years (2) 4.8 4.8 4.9 Risk-free interest rate (3) 1.97 % 1.41 % 1.36 % Expected dividend yield 3.28 % 4.49 % 3.64 % Fair value per award $ 8.27 $ 5.97 $ 5.46 ( 1 Measured using daily price changes of Company’s stock over respective expected term of the option and the implied volatility derived from the market prices of the Company’s stock and traded options. ( 2 The number of years that the Company estimates that the options will be outstanding prior to exercise. ( 3 The risk-free rate over the expected life based on the US Treasury yield curve in effect at the time of the grant. Employee stock option grants are being expensed by the Company over the grants’ three December 31, 2017 930 A summary of option activity during the year ended December 31, 2017 Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (In thousands) (Years) Outstanding at January 1, 2017 1,273 $ 47.36 Granted 266 57.18 Exercised (509 ) 48.29 Forfeited or expired - N/A Outstanding at December 31, 2017 1,030 49.44 6.0 Exercisable at December 31, 2017 469 49.45 3.1 A summary of the Company’s nonvested option activity during the year ended December 31, 2017 Shares Weighted (In thousands) Nonvested at January 1, 2017 553 $ 5.80 Granted 266 8.27 Vested (258 ) 5.78 Forfeited - N/A Nonvested at December 31, 2017 561 $ 6.98 The weighted average estimated grant date fair value for options granted under the Company’s stock option plan during the twelve December 31, 2017, 2016 2015 $8.27, $5.97 $5.46 December 31, 2017 $2,012 0.9 The total intrinsic value of options exercised during the twelve December 31, 2017, 2016 2015 $4,642 $3,242 $504 twelve December 31, 2017, 2016 2015 $708 $753 $741 twelve December 31, 2017, 2016 2015 $1,493 $1,269 $1,321 January 1, 2017, twelve 2017, 509 $1,667 2017 $698 2016 09. $394 twelve December 31, 2016. $1,284 twelve December 31, 2015. A summary of the status of the Company’s restricted performance shares as of December 31, 2017 2016 twelve 2017 2016 (In thousands) Outstanding at January 1, 48 45 Granted 14 18 Issued upon vesting (13 ) (15 ) Forfeited - - Outstanding at December 31, 49 48 As of December 31, 2017 2016, 1.2 1.1 $827 $1,228 $535 twelve December 31, 2017, 2016 2015, no twelve December 31, 2017 2016. On February 13, 2009, 246,640 $50.92 may not December 31, 2017. The Company repurchases and retires its common stock in accordance with Board of Directors approved share repurchase programs. At December 31, 2017, 1,750 Shareholders have authorized two one million 150 December 31, 2017, no

Note 9 - Regulatory Capital

Note 9 - Regulatory Capital	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Regulatory Capital Requirements under Banking Regulations [Text Block]	Note 9: Banks and bank holding companies are subject to regulatory capital requirements administered by federal banking agencies. Capital adequacy guidelines and, additionally for banks, prompt corrective action regulations, involve quantitative measures of assets, liabilities, and certain off-balance-sheet items calculated under regulatory accounting practices. Capital amounts and classifications are also subject to qualitative judgments by regulators. Failure to meet capital requirements can result in regulatory action. The final rules implementing Basel Committee on Banking Supervision’s capital guidelines for U.S. banks (Basel III rules) became effective for the Company on January 1, 2015 January 1, 2019. 0.0% 2015 2.50% 2019. 2017 1.25% 0.625% 2016. not December 31, 2017, Prompt corrective action regulations provide five not 2017 2016, no The capital ratios for the Company and the Bank under the new capital framework as of the dates indicated are presented in the table below. At December 31, 2017 Required To Be Well-capitalized Amount Ratio Amount Ratio Amount Ratio ($ in thousands) Common Equity Tier 1 Capital Company $ 479,259 15.36 % $ 179,377 5.75 % (1) N/A N/A Bank 383,796 12.50 % 176,568 5.75 % (1) $ 199,599 6.50 % Tier 1 Capital Company 479,259 15.36 % 226,170 7.25 % (1) N/A N/A Bank 383,796 12.50 % 222,630 7.25 % (1) 245,660 8.00 % Total Capital Company 504,576 16.17 % 288,562 9.25 % (1) N/A N/A Bank 415,113 13.52 % 284,045 9.25 % (1) 307,076 10.00 % Leverage Ratio (2) Company 479,259 8.86 % 216,280 4.000 % N/A N/A Bank 383,796 7.16 % 214,468 4.000 % 268,085 5.00 % ( 1 1.25% ( 2 1capital At December 31, 2016 Required To Be Well-capitalized Amount Ratio Amount Ratio Amount Ratio ($ in thousands) Common Equity Tier 1 Capital Company $ 443,574 14.85 % $ 153,126 5.125 % (3) N/A N/A Bank 344,739 11.70 % 150,982 5.125 % (3) $ 191,489 6.50 % Tier 1 Capital Company 443,574 14.85 % 197,944 6.625 % (3) N/A N/A Bank 344,739 11.70 % 195,172 6.625 % (3) 235,680 8.00 % Total Capital Company 476,595 15.95 % 257,700 8.625 % (3) N/A N/A Bank 383,572 13.02 % 254,092 8.625 % (3) 294,600 10.00 % Leverage Ratio (2) Company 443,574 8.46 % 209,702 4.000 % N/A N/A Bank 344,739 6.63 % 208,005 4.000 % 260,006 5.00 % ( 3 0.625% ( 2 1capital

Note 10 - Income Taxes

Note 10 - Income Taxes	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Income Tax Disclosure [Text Block]	Note 10: Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the amounts reported in the financial statements of existing assets and liabilities and their respective tax basis and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. Amounts for the current year are based upon estimates and assumptions as of the date of these financial statements and could vary significantly from amounts shown on the tax returns as filed. The components of the net deferred tax asset are as follows: At December 31, 2017 2016 (In thousands) Deferred tax asset Allowance for credit losses $ 7,349 $ 11,801 State franchise taxes 1,871 2,679 AMT carryforward 1,752 - Securities available for sale 8,586 7,283 Deferred compensation 5,279 8,043 Real estate owned 553 756 Purchased assets and assumed liabilities 1,111 3,026 Post-retirement benefits 526 903 Employee benefit accruals 2,066 3,399 VISA Class B shares 96 137 Limited partnership investments 57 86 Impaired capital assets 3,056 18,465 Accrued liabilities 1,609 967 Premises and equipment 299 577 Other 520 724 Total deferred tax asset 34,730 58,846 Deferred tax liability Net deferred loan fees 281 346 Intangible assets 1,247 2,955 Other 90 128 Total deferred tax liability 1,618 3,429 Net deferred tax asset $ 33,112 $ 55,417 Based on Management’s judgment, a valuation allowance is not not The provision for federal and state income taxes consists of amounts currently payable and amounts deferred are as follows: For the Years Ended December 31, 2017 2016 2015 (In thousands) Current income tax expense: Federal $ 1,778 $ 16,258 $ 9,647 State 7,810 7,292 6,738 Total current 9,588 23,550 16,385 Deferred income tax (benefit) expense: Federal 14,461 (2,604 ) 1,643 State 783 158 (109 ) Total deferred 15,244 (2,446 ) 1,534 Adjustment of net deferred tax asset for enacted changes in tax rates: Federal 12,315 - - State - - - Total adjustments 12,315 $ - $ - Provision for income taxes $ 37,147 $ 21,104 $ 17,919 The provision for income taxes differs from the provision computed by applying the statutory federal income tax rate to income before taxes, as follows: For the Years Ended December 31, 2017 2016 2015 (In thousands) Federal income taxes due at statutory rate $ 30,509 $ 27,985 $ 26,835 Reductions in income taxes resulting from: Interest on state and municipal securities and loans not taxable for (7,794 ) (8,382 ) (9,046 ) State franchise taxes, net of federal income tax benefit 5,586 4,843 4,309 Re-measurement of net deferred tax asset due to enactment of new federal tax rate 12,315 - - Stock compensation deduction in excess of book expense (583 ) - - Tax credits (1,850 ) (2,286 ) (2,600 ) Dividend received deduction (60 ) (52 ) (45 ) Cash value life insurance (603 ) (607 ) (599 ) Other (373 ) (397 ) (935 ) Provision for income taxes $ 37,147 $ 21,104 $ 17,919 The 2017 $12.3 2017. December 31, 2017, no $1,752 2017 2022. A reconciliation of the beginning and ending amounts of unrecognized tax benefits follow: 2017 2016 (In thousands) Balance at January 1, $ 1,099 $ 1,243 Additions for tax positions taken in the current period - - Reductions for tax positions taken in the current period - - Additions for tax positions taken in prior years - - Reductions for tax positions taken in prior years - (144 ) Decrease related to settlements with taxing authorities (190 ) - Decrease as a result of a lapse in statute of limitations - - Balance at December 31, $ 909 $ 1,099 The deductibility of these tax positions will be determined through examination by the appropriate tax jurisdictions or the expiration of the tax statute of limitations. The Company does not 2018. December 31, 2017 2016 $13 $57 The Company classifies interest and penalties as a component of the provision for income taxes. At December 31, 2017, December 31, 2016, 2015 2014 December 31, 2016 2015, 2014, 2013, 2012 2011

Note 11 - Fair Value Measuremen

Note 11 - Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Fair Value Disclosures [Text Block]	Note 11: The Company uses fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. Available for sale investment securities are recorded at fair value on a recurring basis. Additionally, from time to time, the Company may In accordance with the Fair Value Measurement and Disclosure topic of the Codification, the Company bases its fair values on the price that would be received to sell an asset or paid to transfer a liability in the principal market or most advantageous market for an asset or liability in an orderly transaction between market participants on the measurement date under current market conditions. A fair value measurement reflects all of the assumptions that market participants would use in pricing the 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. The Company groups its assets and liabilities measured at fair value into a three Level 1 1 Level 2 not 2 Level 3 not The Company relies on independent vendor pricing services to measure fair value for investment securities available for sale and investment securities held to maturity. The Company employs three 95 may not The Company regularly reviews the valuation techniques and assumptions used by its vendors and determines which valuation techniques are utilized based on observable market inputs for the type of securities being measured. The Company uses the information to determine the placement in the fair value hierarchy as level 1, 2 3. may December 31, 2017 2016, no 1, 2 3. Assets Recorded at Fair Value on a Recurring Basis The tables below present assets measured at fair value on a recurring basis on the dates indicated. At December 31, 2017 Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs (In thousands) Securities of U.S. Government sponsored entities $ 119,319 $ - $ 119,319 $ - Agency residential MBS 767,706 - 767,706 - Non-agency residential MBS 154 - 154 - Agency commercial MBS 2,219 - 2,219 - Securities of U.S. Government entities 1,590 - 1,590 - Obligations of states and political subdivisions 185,221 - 185,221 - Corporate securities 1,115,498 - 1,115,498 - Other securities 1,800 - 1,800 - Total securities available for sale $ 2,193,507 $ - $ 2,193,507 $ - At December 31, 2016 Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs (In thousands) Securities of U.S. Government sponsored entities $ 138,660 $ - $ 138,660 $ - Agency residential MBS 691,499 - 691,499 - Non-agency residential MBS 271 - 271 - Securities of U.S. Government entities 2,025 - 2,025 - Obligations of states and political subdivisions 183,411 - 183,411 - Asset-backed securities 695 - 695 - FHLMC and FNMA stock 10,869 17 10,852 - Corporate securities 860,857 - 860,857 - Other securities 2,471 656 1,815 - Total securities available for sale $ 1,890,758 $ 673 $ 1,890,085 $ - Assets Recorded at Fair Value on a Nonrecurring Basis The Company may December 31, 2017 December 31, 2016, For the Year Ended At December 31, 2017 December 31, 2017 Carrying Value Level 1 Level 2 Level 3 Total Losses (In thousands) Other real estate owned $ 1,426 $ - $ - $ 1,426 $ (219 ) Impaired loans: Commercial 4,950 - - 4,950 - Commercial real estate 5,904 - - 5,904 - Total assets measured at fair value on a nonrecurring basis $ 12,280 $ - $ - $ 12,280 $ (219 ) For the Year Ended At December 31, 2016 December 31, 2016 Carrying Value Level 1 Level 2 Level 3 Total Losses (In thousands) Other real estate owned $ 3,095 $ - $ - $ 3,095 $ (705 ) Impaired loans: Commercial 5,115 - - 5,115 - Commercial real estate 4,410 - - 4,410 - Total assets measured at fair value on a nonrecurring basis $ 12,620 $ - $ - $ 12,620 $ (705 ) Level 3 third 10% 3 not not Disclosures about Fair Value of Financial Instruments The following section describes the valuation methodologies used by the Company for estimating fair value of financial instruments not Cash and Due from Banks Investment Securities Held to Maturity 2 Loans two $23,009 December 31, 2017 $25,954 December 31, 2016 Deposit Liabilities no no Short-Term Borrowed Funds The table below is a summary of fair value estimates for financial instruments and the level of the fair value hierarchy within which the fair value measurements are categorized, excluding financial instruments recorded at fair value on a recurring basis. The values assigned do not may not may The Company has not not not not At December 31, 2017 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: (In thousands) Cash and due from banks $ 575,002 $ 575,002 $ 575,002 $ - $ - Investment securities held to maturity 1,158,864 1,155,342 - 1,155,342 - Loans 1,264,973 1,257,811 - - 1,257,811 Financial Liabilities: Deposits $ 4,827,613 $ 4,824,586 $ - $ 4,595,795 $ 228,791 Short-term borrowed funds 58,471 58,471 - 58,471 - At December 31, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: (In thousands) Cash and due from banks $ 462,271 $ 462,271 $ 462,271 $ - $ - Investment securities held to maturity 1,346,312 1,340,741 - 1,340,741 - Loans 1,326,757 1,337,774 - - 1,337,774 Financial Liabilities: Deposits $ 4,704,741 $ 4,702,797 $ - $ 4,448,571 $ 254,226 Short-term borrowed funds 59,078 59,078 - 59,078 - The majority of the Company’s standby letters of credit and other commitments to extend credit carry current market interest rates if converted to loans. No

Note 12 - Lease Commitments

Note 12 - Lease Commitments	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Leases of Lessee Disclosure [Text Block]	Note 12: Twenty nine 58 Minimum future rental payments under noncancelable operating leases as of December 31, 2017 Minimum (In thousands) 2018 $ 6,481 2019 4,882 2020 3,143 2021 1,462 2022 732 Thereafter 825 Total minimum lease payments $ 17,525 The total minimum future rental payments have not $2,088 $6,695 2017, $6,823 2016 $8,359 2015. $406 2017, $435 2016 $1,721 2015. $6,289 2017, $6,388 2016 $6,638 2015.

Note 13 - Commitments and Conti

Note 13 - Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	Note 13: Loan commitments are agreements to lend to a customer provided there is no not $272,646 $304,508 December 31, 2017 2016, $19,263 $21,732 December 31, 2017 2016, no December 31, 2017 2016. $2,308 December 31, 2017 $2,408 December 31, 2016, Due to the nature of its business, the Company is subject to various threatened or filed legal cases. Based on the advice of legal counsel, the Company does not The Company has determined that it will be obligated to provide refunds of revenue recognized in prior years to some customers. The Company estimates the probable amount of these obligations will be $5,542 The October 2017 not Management has performed an initial evaluation of loss exposure caused by the wildfires within the Company's loan portfolio and investment portfolio; Management has not not

Note 14 - Retirement Benefit Pl

Note 14 - Retirement Benefit Plans	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Pension and Other Postretirement Benefits Disclosure [Text Block]	Note 14: The Company sponsors a qualified defined contribution Deferred Profit-Sharing Plan covering substantially all of its salaried employees with one $944 2017, $1,000 2016 $734 2015. The Company also sponsors a qualified defined contribution Tax Deferred Savings/Retirement Plan (ESOP) covering salaried employees who become eligible to participate upon completion of a 90 may one $1,098 2017, $1,075 2016 $1,147 2015. The Company offers a continuation of group insurance coverage to eligible employees electing early retirement, for the period from the date of retirement until age 65. 65 February 1, 2006 January 1, 2019. December 31 The following tables set forth the net periodic post-retirement benefit cost and the change in the benefit obligation for the years ended December 31 December 31: Net Periodic Benefit Cost At December 31, 2017 2016 2015 (In thousands) Service benefit $ (311 ) $ (153 ) $ (202 ) Interest cost 95 108 106 Amortization of unrecognized transition obligation 61 61 61 Net periodic (benefit) cost $ (155 ) $ 16 $ (35 ) Other Changes in Benefit Obligations Recognized in Other Comprehensive Income Amortization of unrecognized transition obligation, net of tax (34 ) (36 ) (36 ) Total recognized in net periodic (benefit) cost and accumulated other comprehensive income $ (189 ) $ (20 ) $ (71 ) The transition obligation for this post-retirement benefit plan became fully amortized during the twelve December, 2017. Obligation and Funded Status At December 31, 2017 2016 2015 Change in benefit obligation (In thousands) Benefit obligation at beginning of year $ 2,319 $ 2,522 $ 2,782 Service benefit $ (311 ) $ (153 ) (202 ) Interest cost 95 108 106 Benefits paid (145 ) (158 ) (164 ) Benefit obligation at end of year $ 1,958 $ 2,319 $ 2,522 Accumulated post-retirement benefit obligation attributable to: Retirees $ 1,575 $ 1,705 $ 1,695 Fully eligible participants 382 606 809 Other 1 8 18 Total $ 1,958 $ 2,319 $ 2,522 Fair value of plan assets - - - Accumulated post-retirement benefit obligation in excess of plan assets $ 1,958 $ 2,319 $ 2,522 Additional Information Assumptions At December 31, 2017 2016 2015 Weighted-average assumptions used to determine benefit obligations Discount rate 3.70 % 4.10 % 4.30 % Weighted-average assumptions used to determine net periodic benefit cost Discount rate 4.10 % 4.30 % 3.80 % The above discount rate is based on the Corporate Aa 25 zero 2017 Assumed benefit inflation rates are not Estimated future benefit payments (In thousands) 2018 $ 138 2019 131 2020 124 2021 118 2022 112 Years 2023-2027 482

Note 15 - Related Party Transac

Note 15 - Related Party Transactions	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Related Party Transactions Disclosure [Text Block]	Note 15: Certain of the Directors, executive officers and their associates have had banking transactions with subsidiaries of the Company in the ordinary course of business. In Management’s opinion, with the exception of the Company’s Employee Loan Program, all outstanding loans and commitments included in such transactions were made on substantially the same terms, including interest rates and collateral, as those prevailing at the time for comparable transactions with other persons, did not not one 22 The table below reflects information concerning loans to certain directors and executive officers and/or family members during 2017 2016: 2017 2016 (In thousands) Balance at January 1, $ 867 $ 911 Originations - - Principal reductions $ (245 ) (44 ) Balance at December 31, $ 622 $ 867 Percent of total loans outstanding. 0.05 % 0.06 %

Note 16 - Regulatory Matters

Note 16 - Regulatory Matters	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Regulatory Matters [Text Block]	Note 16: Payment of dividends to the Company by the Bank is limited under regulations for state chartered banks. The amount that can be paid in any calendar year, without prior approval from regulatory agencies, cannot exceed the net profits (as defined) for the preceding three 2017. 1972. The Bank is required to maintain reserves with the Federal Reserve Bank equal to a percentage of its reservable deposits. The Bank’s daily average on deposit at the Federal Reserve Bank was $458,186 2017 $365,880 2016,

Note 17 - Other Comprehensive I

Note 17 - Other Comprehensive Income	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Comprehensive Income (Loss) Note [Text Block]	Note 17: The components of other comprehensive (loss) income and other related tax effects were: 2017 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (3,767 ) $ 1,585 $ (2,182 ) Reclassification of gains included in net income (7,955 ) 3,345 (4,610 ) Net unrealized losses arising during the year (11,722 ) 4,930 (6,792 ) Post-retirement benefit obligation 59 (25 ) 34 Other comprehensive loss $ (11,663 ) $ 4,905 $ (6,758 ) 2016 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (18,610 ) $ 7,825 $ (10,785 ) Reclassification of gains (losses) included in net income - - - Net unrealized losses arising during the year (18,610 ) 7,825 (10,785 ) Post-retirement benefit obligation 61 (25 ) 36 Other comprehensive loss $ (18,549 ) $ 7,800 $ (10,749 ) 2015 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (8,028 ) $ 3,375 $ (4,653 ) Reclassification of gains (losses) included in net income - - - Net unrealized losses arising during the year (8,028 ) 3,375 (4,653 ) Post-retirement benefit obligation 61 (25 ) 36 Other comprehensive loss $ (7,967 ) $ 3,350 $ (4,617 ) Accumulated other comprehensive income (loss) balances were: Post-retirement Benefit Obligation Net Unrealized Gains (losses) on Securities Accumulated Other Comprehensive Income (loss) (In thousands) Balance, December 31, 2014 $ (106 ) $ 5,398 $ 5,292 Net change 36 (4,653 ) (4,617 ) Balance, December 31, 2015 (70 ) 745 675 Net change 36 (10,785 ) (10,749 ) Balance, December 31, 2016 (34 ) (10,040 ) (10,074 ) Net change 34 (6,792 ) (6,758 ) Balance, December 31, 2017 $ - $ (16,832 ) $ (16,832 )

Note 18 - Earnings Per Common S

Note 18 - Earnings Per Common Share	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Earnings Per Share [Text Block]	Note 18: The table below shows earnings per common share and diluted earnings per common share. Basic earnings per common share are computed by dividing net income by the average number of common shares outstanding during the period. Diluted earnings per common share are computed by dividing net income by the average number of common shares outstanding during the period plus the impact of common stock equivalents. For the Years Ended December 31, 2017 2016 2015 (In thousands, except per share data) Net income (numerator) $ 50,025 $ 58,853 $ 58,753 Basic earnings per common share Weighted average number of common shares outstanding - basic (denominator) 26,291 25,612 25,555 Basic earnings per common share $ 1.90 $ 2.30 $ 2.30 Diluted earnings per common share Weighted average number of common shares outstanding - basic 26,291 25,612 25,555 Add common stock equivalents for options 128 66 22 Weighted average number of common shares outstanding - diluted (denominator) 26,419 25,678 25,577 Diluted earnings per common share $ 1.89 $ 2.29 $ 2.30 For the years ended December 31, 2017, 2016 2015, 323 773 1,313 not

Note 19 - Westamerica Bancorpor

Note 19 - Westamerica Bancorporation (Parent Company Only Condensed Financial Information)	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Condensed Financial Information of Parent Company Only Disclosure [Text Block]	Note 19: Statements of Income and Comprehensive Loss For the Years Ended December 31, 2017 2016 2015 (In thousands) Dividends from subsidiaries $ 12,728 $ 56,824 $ 68,981 Interest income 43 25 10 Other income 8,590 8,315 8,411 Total income 21,361 65,164 77,402 Interest on borrowings - - 1 Salaries and benefits 7,163 7,079 6,291 Other expense 3,416 3,290 3,424 Total expense 10,579 10,369 9,716 Income before taxes and equity in undistributed income of subsidiaries 10,782 54,795 67,686 Income tax benefit 241 1,025 803 Earnings of subsidiaries greater (less) than subsidiary dividends 39,002 3,033 (9,736 ) Net income 50,025 58,853 58,753 Other comprehensive loss, net of tax (6,758 ) (10,749 ) (4,617 ) Comprehensive income $ 43,267 $ 48,104 $ 54,136 Balance Sheets At December 31, 2017 2016 (In thousands) Assets Cash $ 53,409 $ 64,054 Investment securities available for sale - 656 Investment in Westamerica Bank 500,776 468,172 Investment in non-bank subsidiaries 455 455 Premises and equipment, net 9,639 9,165 Accounts receivable from Westamerica Bank 538 522 Other assets 40,547 34,077 Total assets $ 605,364 $ 577,101 Liabilities Accounts payable to Westamerica Bank $ 92 $ 705 Other liabilities 15,033 15,029 Total liabilities 15,125 15,734 Shareholders' equity 590,239 561,367 Total liabilities and shareholders' equity $ 605,364 $ 577,101 Statements of Cash Flows For the Years Ended December 31, 2017 2016 2015 (In thousands) Operating Activities Net income $ 50,025 $ 58,853 $ 58,753 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation and amortization 319 305 326 Decrease (increase) in accounts receivable from affiliates (16 ) 299 (217 ) Insurance premiums paid (704 ) (683 ) (637 ) Increase in other assets (1,499 ) (1,257 ) (1,076 ) Stock option compensation expense 1,824 1,494 1,272 Tax benefit (increase) decrease upon exercise of stock options and expiration of stock options - (394 ) 1,284 Provision (benefit) for deferred income tax (3,971 ) 1,983 (491 ) Increase in other liabilities 202 1,392 743 Earnings of subsidiaries (greater) less than subsidiary dividends (39,002 ) (3,033 ) 9,736 Gain on sales of property and equipment (793 ) (79 ) (39 ) Net Cash Provided by Operating Activities 6,385 58,880 69,654 Investing Activities Purchases of premises and equipment - - - Net Cash Provided by Investing Activities - - - Financing Activities Exercise of stock options/issuance of shares 24,583 24,031 4,848 Taxes paid by withholding shares for tax purposes - (356 ) (357 ) Tax benefit increase (decrease) upon exercise of stock options and expiration of stock options - 394 (1,284 ) Retirement of common stock (314 ) (5,424 ) (14,735 ) Dividends (41,299 ) (39,924 ) (39,124 ) Net Cash Used in Financing Activities (17,030 ) (21,279 ) (50,652 ) Net change in cash (10,645 ) 37,601 19,002 Cash at Beginning of Period 64,054 26,453 7,451 Cash at End of Period $ 53,409 $ 64,054 $ 26,453 Supplemental Cash Flow Disclosures: Supplemental disclosure of cash flow activities: Interest paid for the period $ - $ - $ 1 Income tax payments for the period 17,351 19,264 17,666

Note 20 - Quarterly Financial I

Note 20 - Quarterly Financial Information	12 Months Ended
	Dec. 31, 2017
Notes to Financial Statements
Quarterly Financial Information [Text Block]	Note 20: (Unaudited) For the Three Months Ended March 31, June 30, September 30, December 31, (In thousands, expect per share data and 2017 Interest and loan fee income $ 33,324 $ 33,163 $ 33,145 $ 34,204 Net interest income 32,844 32,687 32,672 33,733 (Reversal of) provision for loan losses - (1,900 ) - - Noninterest income 11,657 12,123 12,548 20,300 Noninterest expense 24,615 24,396 24,114 30,167 Income before taxes 19,886 22,314 21,106 23,866 Net income 15,049 15,799 15,017 4,160 Basic earnings per common share 0.58 0.60 0.57 0.16 Diluted earnings per common share 0.57 0.60 0.57 0.16 Dividends paid per common share 0.39 0.39 0.39 0.40 Price range, common stock 54.12 - 64.07 51.31 - 57.78 49.54 - 59.54 53.96 - 63.03 2016 Interest and loan fee income $ 33,647 $ 33,727 $ 33,468 $ 33,209 Net interest income 33,095 33,186 32,945 32,709 (Reversal of) provision for loan losses - - (3,200 ) - Noninterest income 11,729 11,702 11,598 11,545 Noninterest expense 25,858 25,229 26,088 24,577 Income before taxes 18,966 19,659 21,655 19,677 Net income 14,226 14,546 15,628 14,453 Basic earnings per common share 0.56 0.57 0.61 0.56 Diluted earnings per common share 0.56 0.57 0.61 0.56 Dividends paid per common share 0.39 0.39 0.39 0.39 Price range, common stock 40.72 - 49.63 45.86 - 51.53 46.61 - 50.96 48.20 - 65.34 2015 Interest and loan fee income $ 33,917 $ 34,425 $ 34,299 $ 33,888 Net interest income 33,258 33,808 33,714 33,325 Provision for loan losses - - - - Noninterest income 12,300 12,269 11,993 11,305 Noninterest expense 26,727 26,896 26,173 25,504 Income before taxes 18,831 19,181 19,534 19,126 Net income 14,557 14,761 14,857 14,578 Basic earnings per common share 0.57 0.58 0.58 0.57 Diluted earnings per common share 0.57 0.58 0.58 0.57 Dividends paid per common share 0.38 0.38 0.38 0.39 Price range, common stock 40.68 - 48.44 42.70 - 51.69 43.00 - 51.90 42.96 - 49.64

Significant Accounting Policies

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	Accounting Estimates. Certain accounting policies underlying the preparation of these financial statements require Management to make estimates and judgments about future economic and market conditions. These estimates and judgments may 2018
Consolidation, Policy [Policy Text Block]	Principles of Consolidation. The consolidated financial statements include the accounts of the Company and all the Company’s subsidiaries. Significant intercompany transactions have been eliminated in consolidation. The Company does not
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash. Cash includes Due From Banks balances which are readily convertible to known amounts of cash and are generally 90
Marketable Securities, Policy [Policy Text Block]	Securities. Investment securities consist of debt securities of the U.S. Treasury, government sponsored entities, states, counties, municipalities, corporations, agency and non-agency mortgage-backed securities, asset-backed securities and equity securities. Securities transactions are recorded on a trade date basis. The Company classifies its debt and marketable equity securities in one three not The Company utilizes third 1 2 third one third third not 3 A decline in the market value of any available for sale or held to maturity security below amortized cost that is deemed other than temporary results in a charge to earnings and the establishment of a new cost basis for the security. Unrealized investment securities losses are evaluated at least quarterly to determine whether such declines in value should be considered “other than temporary” and therefore be subject to immediate loss recognition in income. Although these evaluations involve significant judgment, an unrealized loss in the fair value of a debt security is generally deemed to be temporary when the fair value of the security is below the carrying value primarily due to changes in risk-free interest rates, there has not not not not may The Company follows the guidance issued by the Board of Governors of the Federal Reserve System, “Investing in Securities without Reliance on Nationally Recognized Statistical Rating Agencies” (SR 12 15 Purchase premiums are amortized and purchase discounts are accreted over the estimated life of the related investment security as an adjustment to yield using the effective interest method. Unamortized premiums, unaccreted discounts, and early payment premiums are recognized as a component of gain or loss on sale upon disposition of the related security. Interest and dividend income are recognized when earned. Realized gains and losses from the sale of available for sale securities are included in earnings using the specific identification method.
Cost Method Investments, Policy [Policy Text Block]	Nonmarketable Equity Securities. Nonmarketable equity securities include securities that are not
Finance, Loans and Leases Receivable, Policy [Policy Text Block]	Loans. Loans are stated at the principal amount outstanding, net of unearned discount and unamortized deferred fees and costs. Interest is accrued daily on the outstanding principal balances. Loans which are more than 90 120 The Company evaluates all classified loans and nonaccrual loans with outstanding principal balances in excess of $500 310 40, not Nonrefundable fees and certain costs associated with originating or acquiring loans are deferred and amortized as an adjustment to interest income over the contractual loan lives. Upon prepayment, unamortized loan fees, net of costs, are immediately recognized in interest income. Other fees, including those collected upon principal prepayments, are included in interest income when received. Loans held for sale are identified upon origination and are reported at the lower of cost or market value on an aggregate loan basis. Purchased Loans. Purchased loans are recorded at estimated fair value on the date of purchase. Impaired purchased loans are accounted for under FASB ASC 310 30, not may 310 30. 310 30 not 310 30 Covered Loans. Loans covered under loss-sharing or similar credit protection agreements with the FDIC are reported in loans exclusive of the expected reimbursement cash flows from the FDIC. Covered loans are initially recorded at fair value at the acquisition date. Subsequent decreases in the amount expected to be collected results in a provision for loan losses and a corresponding increase in the estimated FDIC reimbursement, with the estimated net loss impacting earnings. Interest previously accrued on covered loans placed on nonaccrual status is charged against interest income, net of estimated FDIC reimbursements of such accrued interest. The FDIC reimburses the Company up to 80% 90
Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]	Allowance for Credit Losses. The Company extends loans to commercial and consumer customers primarily in Northern and Central California. These lending activities expose the Company to the risk borrowers will default, causing loan losses. The Company’s lending activities are exposed to various qualitative risks. All loan segments are exposed to risks inherent in the economy and market conditions. Significant risk characteristics related to the commercial loan segment include the borrowers’ business performance and financial condition, and the value of collateral for secured loans. Significant risk characteristics related to the commercial real estate segment include the borrowers’ business performance and the value of properties collateralizing the loans. Significant risk characteristics related to the construction loan segment include the borrowers’ performance in successfully developing the real estate into the intended purpose and the value of the property collateralizing the loans. Significant risk characteristics related to the residential real estate segment include the borrowers’ financial wherewithal to service the mortgages and the value of the property collateralizing the loans. Significant risk characteristics related to the consumer loan segment include the financial condition of the borrowers and the value of collateral securing the loans. The preparation of these financial statements requires Management to estimate the amount of probable incurred losses inherent in the loan portfolio and establish an allowance for credit losses. The allowance for credit losses is established by assessing a provision for loan losses against the Company’s earnings. In estimating credit losses, Management must exercise significant judgment in evaluating information deemed relevant, such as financial information regarding individual borrowers, overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions and other information. The amount of ultimate losses on the loan portfolio can vary from the estimated amounts. Management follows a systematic methodology to estimate loss potential in an effort to reduce the differences between estimated and actual losses. The allowance for credit losses is established through provisions for credit losses charged to income. Losses on loans, including impaired loans, are charged to the allowance for loan losses when all or a portion of the recorded amount of a loan is deemed to be uncollectible. Recoveries of loans previously charged off are credited to the allowance when realized. The Company’s allowance for credit losses is maintained at a level considered adequate to provide for losses that can be estimated based upon specific and general conditions. These include conditions unique to individual borrowers, as well as overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions, FDIC loss-sharing or similar credit protection agreements and other factors. A portion of the allowance is specifically allocated to impaired loans whose full collectability is uncertain. Such allocations are determined by Management based on loan-by-loan analyses. The Company evaluates all classified loans and nonaccrual loans with outstanding principal balances in excess of $500 second not not not not
Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]	Liability for Off-Balance Sheet Credit Exposures. A liability for off-balance sheet credit exposures is established through expense recognition. Off-balance sheet credit exposures relate to letters of credit and unfunded loan commitments for commercial, construction and consumer loans. Historical credit loss factors for commercial, construction and consumer loans are applied to the amount of these off-balance sheet credit exposures to estimate inherent losses.
Loans and Leases Receivable, Real Estate Acquired Through Foreclosure, Policy [Policy Text Block]	Other Real Estate Owned. Other real estate owned is comprised of property acquired through foreclosure proceedings, acceptances of deeds-in-lieu of foreclosure and, if applicable, vacated bank properties. Losses recognized at the time of acquiring property in full or partial satisfaction of debt are charged against the allowance for credit losses. Other real estate owned is recorded at the fair value of the collateral, generally based upon an independent property appraisal, less estimated disposition costs. Losses incurred subsequent to acquisition due to any decline in annual independent property appraisals are recognized as noninterest expense. Routine holding costs, such as property taxes, insurance and maintenance, and losses from sales and dispositions, are recognized as noninterest expense. Covered Other Real Estate Owned. Other real estate owned covered under loss-sharing agreements with the FDIC is reported exclusive of expected reimbursement cash flows from the FDIC. Upon transferring covered loan collateral to covered other real estate owned status, the covered loan collateral is recorded at fair value, generally based upon an independent property appraisal, less estimated disposition costs with losses charged against acquisition date fair value discounts; the amount of losses exceeding acquisition date fair value discounts are recognized as noninterest expense inclusive of expected reimbursement cash flows from the FDIC. Subsequent losses incurred due to any decline in annual independent property appraisal valuations are recognized as noninterest expense inclusive of expected reimbursement cash flows from the FDIC.
Property, Plant and Equipment, Policy [Policy Text Block]	Premises and Equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed substantially on the straight-line method over the estimated useful life of each type of asset. Estimated useful lives of premises and equipment range from 20 50 3 20
Revenue Recognition, Policy [Policy Text Block]	Revenue Recognition. The Company recognizes revenue as it is earned based on contractual terms, as transactions occur, or as services are provided and collectability is reasonably assured. In certain circumstances, noninterest income is reported net of associated expenses that are directly related to variable volume-based sales or revenue sharing arrangements or when the Company acts on an agency basis for others.
Life Insurance Cash Surrender Value [Policy Text Block]	Life Insurance Cash Surrender Value. The Company has purchased life insurance policies on certain directors and officers as well as acquired such assets as part of the acquisition of other banks. Company owned life insurance is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. These assets are included in other assets on the consolidated balance sheets.
Goodwill and Intangible Assets, Policy [Policy Text Block]	Intangible Assets. Intangible assets are comprised of goodwill, core deposit intangibles and other identifiable intangibles acquired in business combinations. Intangible assets with definite useful lives are amortized on an accelerated basis over their respective estimated useful lives not 15 may not not first 2011 08, Testing for Goodwill Impairment. first
Impairment of Long Lived Assets [Policy Text Block]	Impairment of Long-Lived Assets. The Company reviews its long-lived and certain intangible assets for impairment whenever events or changes indicate that the carrying amount of an asset may not
Income Tax, Policy [Policy Text Block]	Income Taxes. The Company and its subsidiaries file consolidated tax returns. The Company accounts for income taxes in accordance with FASB ASC 740, two not. not fifty
Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]	Stock Options. The Company applies FASB ASC 718 no
Extinguishment of Debt [Policy Text Block]	Extinguishment of Debt. Gains and losses, including fees, incurred in connection with the early extinguishment of debt are charged to current earnings as reductions in noninterest income.
Postemployment Benefit Plans, Policy [Policy Text Block]	Postretirement Benefits. The Company uses an actuarial-based accrual method of accounting for post-retirement benefits.
Fiduciary [Policy Text Block]	Other. Securities and other property held by the Bank in a fiduciary or agency capacity are not not
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Adopted Accounting Standards In 2017, FASB Accounting Standards Update (ASU) 2016 09, Improvements to Employee Share-Based Payment Accounting, March 30, 2016. 1 2 3 January 1, 2017, 2017, 509 $1,667 2017 $698 2016 09. Recently Issued Accounting Standards FASB ASU 2014 09 Revenue (Topic 606 May 2014. not 606 not Approximately 73% not January 1, 2018. FASB ASU 2016 01 Financial Instruments – Overall (Subtopic 825 10 January 2016. The Company was required to adopt the ASU provisions on January 1, 2018, not December 31, 2017, $2000 FASB ASU 2016 02, Leases (Topic 842 February 25, 2016. The Company will be required to adopt the ASU provisions January 1, 2019, December 31, 2017, 58 $17.5 not FASB ASU 2016 13, Financial Instruments – Credit Losses (Topic 326 June 16, 2016. The Company will be required to adopt the ASU provisions on January 1, 2020. FASB ASU 2017 08 Receivables – Non-Refundable Fees and Other Costs (Subtopic 310 20 March 2017. not The Company will be required to adopt the ASU provisions on January 1, 2019. FASB ASU 2017 12 Derivatives and Hedging (Topic 815 August 2017. one The Company will be required to adopt the ASU provisions January 1, 2019. not may one

Note 2 - Investment Securities

Note 2 - Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Available-for-sale Securities Reconciliation [Table Text Block]	Investment Securities Available for Sale Amortized Gross Gross Fair (In thousands) Securities of U.S. Government sponsored entities $ 122,285 $ 1 $ (2,967 ) $ 119,319 Agency residential mortgage-backed securities (MBS) 787,679 522 (20,495 ) 767,706 Non-agency residential MBS 153 1 - 154 Agency commercial MBS 2,244 - (25 ) 2,219 Securities of U.S. Government entities 1,612 - (22 ) 1,590 Obligations of states and political subdivisions 182,907 3,796 (1,482 ) 185,221 Corporate securities 1,123,671 1,104 (9,277 ) 1,115,498 Other securities 2,000 - (200 ) 1,800 Total $ 2,222,551 $ 5,424 $ (34,468 ) $ 2,193,507 Investment Securities Available for Sale Amortized Gross Gross Value (In thousands) Securities of U.S. Government sponsored entities $ 141,599 $ 35 $ (2,974 ) $ 138,660 Agency residential MBS 711,623 921 (21,045 ) 691,499 Non-agency residential MBS 272 - (1 ) 271 Securities of U.S. Government entities 2,041 - (16 ) 2,025 Obligations of states and political subdivisions 182,230 5,107 (3,926 ) 183,411 Asset-backed securities 696 - (1 ) 695 FHLMC (1) (2) 749 10,120 - 10,869 Corporate securities 866,835 1,690 (7,668 ) 860,857 Other securities 2,034 621 (184 ) 2,471 Total $ 1,908,079 $ 18,494 $ (35,815 ) $ 1,890,758
Held-to-maturity Securities [Table Text Block]	Investment Securities Held to Maturity Amortized Gross Gross Fair (In thousands) Agency residential MBS $ 545,883 $ 606 $ (9,850 ) $ 536,639 Non-agency residential MBS 4,462 70 - 4,532 Agency commercial MBS 9,041 - (66 ) 8,975 Obligations of states and political subdivisions 599,478 7,736 (2,018 ) 605,196 Total $ 1,158,864 $ 8,412 $ (11,934 ) $ 1,155,342 Investment Securities Held to Maturity Amortized Gross Gross Fair (In thousands) Securities of U.S. Government sponsored entities $ 581 $ 1 $ - $ 582 Agency residential MBS 668,235 1,122 (8,602 ) 660,755 Non-agency residential MBS 5,370 76 - 5,446 Agency commercial MBS 9,332 11 (143 ) 9,200 Obligations of states and political subdivisions 662,794 6,031 (4,067 ) 664,758 Total $ 1,346,312 $ 7,241 $ (12,812 ) $ 1,340,741
Investments Classified by Contractual Maturity Date [Table Text Block]	At December 31, 2017 Securities Available Securities Held Amortized Fair Amortized Fair (In thousands) Maturity in years: 1 year or less $ 193,337 $ 193,385 $ 50,295 $ 51,105 Over 1 to 5 years 1,031,807 1,023,047 269,050 269,471 Over 5 to 10 years 159,266 160,042 277,170 281,546 Over 10 years 46,065 45,154 2,963 3,074 Subtotal 1,430,475 1,421,628 599,478 605,196 MBS 790,076 770,079 559,386 550,146 Other securities 2,000 1,800 - - Total $ 2,222,551 $ 2,193,507 $ 1,158,864 $ 1,155,342 At December 31, 2016 Securities Available Securities Held Amortized Fair Amortized Fair (In thousands) Maturity in years: 1 year or less $ 154,693 $ 154,835 $ 14,961 $ 15,639 Over 1 to 5 years 750,834 745,219 292,024 292,062 Over 5 to 10 years 238,077 239,153 318,580 319,587 Over 10 years 47,756 44,416 37,810 38,052 Subtotal 1,191,360 1,183,623 663,375 665,340 MBS 713,936 693,795 682,937 675,401 Other securities 2,783 13,340 - - Total $ 1,908,079 $ 1,890,758 $ 1,346,312 $ 1,340,741
Schedule of Unrealized Loss on Investments [Table Text Block]	Investment Securities Available for Sale At December 31, 2017 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Value Unrealized Investment Fair Value Unrealized Investment Fair Value Unrealized ($ in thousands) Securities of U.S. Government sponsored entities 1 $ 996 $ ( 2 ) 8 $ 117,252 $ (2,965 ) 9 $ 118,248 $ ( 2,967 ) Agency residential MBS 7 238,554 (1,501 ) 51 516,711 (18,994 ) 58 755,265 (20,495 ) Non-agency residential MBS 1 1 - - - - 1 1 - Agency commercial MBS 2 2,219 (25 ) - - - 2 2,219 (25 ) Securities of U.S. Government entities - - - 3 1,590 (22 ) 3 1,590 (22 ) Obligations of states and political subdivisions 50 21,453 (228 ) 35 52,071 (1,254 ) 85 73,524 (1,482 ) Corporate securities 64 571,112 (4,047 ) 38 282,924 (5,230 ) 102 854,036 (9,277 ) Other securities - - - 1 1,800 (200 ) 1 1,800 (200 ) Total 125 $ 834,335 $ (5,803 ) 136 $ 972,348 $ (28,665 ) 261 $ 1,806,683 $ (34,468 ) Investment Securities Held to Maturity At December 31, 2017 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Value Unrecognized Investment Fair Value Unrecognized Investment Fair Value Unrecognized ($ in thousands) Agency residential MBS 15 $ 30,218 $ (201 ) 65 $ 479,775 $ (9,649 ) 80 $ 509,993 $ (9,850 ) Agency commercial MBS 1 1,913 (4 ) 1 7,062 (62 ) 2 8,975 (66 ) Obligations of states and political subdivisions 146 131,032 (553 ) 59 58,979 (1,465 ) 205 190,011 (2,018 ) Total 162 $ 163,163 $ (758 ) 125 $ 545,816 $ (11,176 ) 287 $ 708,979 $ (11,934 ) Investment Securities Available for Sale At December 31, 2016 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Unrealized Investment Fair Unrealized Investment Fair Unrealized Positions Value Losses Positions Value Losses Positions Value Losses ($ in thousands) Securities of U.S. Government sponsored entities 8 $ 117,227 $ (2,974 ) - $ - $ - 8 $ 117,227 $ (2,974 ) Agency residential MBS 21 524,269 (16,494 ) 28 122,901 (4,551 ) 49 647,170 (21,045 ) Non-agency residential MBS 2 246 (1 ) - - - 2 246 (1 ) Securities of U.S. Government entities 2 1,253 (9 ) 1 772 (7 ) 3 2,025 (16 ) Obligations of states and political subdivisions 43 57,989 (3,905 ) 3 1,117 (21 ) 46 59,106 (3,926 ) Asset-backed securities - - - 1 695 (1 ) 1 695 (1 ) Corporate securities 53 385,175 (6,551 ) 27 96,145 (1,117 ) 80 481,320 (7,668 ) Other securities - - - 1 1,816 (184 ) 1 1,816 (184 ) Total 129 $ 1,086,159 $ (29,934 ) 61 $ 223,446 $ (5,881 ) 190 $ 1,309,605 $ (35,815 ) Investment Securities Held to Maturity At December 31, 2016 No. of Less than 12 months No. of 12 months or longer No. of Total Investment Fair Unrecognized Investment Fair Unrecognized Investment Fair Unrecognized Positions Value Losses Positions Value Losses Positions Value Losses ($ in thousands) Agency residential MBS 66 $ 569,876 $ (8,285 ) 3 $ 10,480 $ (317 ) 69 $ 580,356 $ (8,602 ) Agency commercial MBS - - - 1 7,214 (143 ) 1 7,214 (143 ) Obligations of states and political subdivisions 295 272,496 (3,710 ) 12 13,126 (357 ) 307 285,622 (4,067 ) Total 361 $ 842,372 $ (11,995 ) 16 $ 30,820 $ (817 ) 377 $ 873,192 $ (12,812 )
Interest Income from Investments [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Taxable $ 51,445 $ 42,718 $ 34,472 Tax-exempt from regular federal income tax 20,651 22,194 23,616 Total interest income from investment securities $ 72,096 $ 64,912 $ 58,088

Note 3 - Loans and Allowance 30

Note 3 - Loans and Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Loans Receivable [Table Text Block]	At December 31, 2017 2016 (In thousands) Commercial $ 335,996 $ 354,697 Commercial Real Estate 568,584 542,171 Construction 5,649 2,555 Residential Real Estate 65,183 87,724 Consumer Installment & Other 312,570 365,564 Total $ 1,287,982 $ 1,352,711
Accretable Yield Reconciliation Schedule [Table Text Block]	For the Years Ended December 31, 2017 2016 Accretable yield: (In thousands) Balance at the beginning of the period $ 1,237 $ 1,259 Reclassification from nonaccretable difference 1,852 3,912 Accretion (2,351 ) (3,934 ) Balance at the end of the period $ 738 $ 1,237 Accretion $ (2,351 ) $ (3,934 ) Change in FDIC indemnification 192 1,053 (Increase) in interest income $ (2,159 ) $ (2,881 )
Schedule of Credit Losses Related to Financing Receivables, Current and Noncurrent [Table Text Block]	Allowance for Loan Losses Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Additions: (Reversal) provision (382 ) 431 (1,716 ) (335 ) 1,271 (1,169 ) (1,900 ) Deductions: Chargeoffs (961 ) - - - (4,957 ) - (5,918 ) Recoveries 762 88 1,899 - 2,124 - 4,873 Net loan (losses) recoveries (199 ) 88 1,899 - (2,833 ) - (1,045 ) Total allowance for loan losses $ 7,746 $ 3,849 $ 335 $ 995 $ 6,418 $ 3,666 $ 23,009 Allowance for Credit Losses Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 9,559 $ 4,212 $ 235 $ 1,801 $ 8,001 $ 5,963 $ 29,771 Additions: (Reversal) provision (3,237 ) (1,436 ) (83 ) (471 ) 3,155 (1,128 ) (3,200 ) Deductions: Chargeoffs (2,023 ) - - - (4,749 ) - (6,772 ) Recoveries 4,028 554 - - 1,573 - 6,155 Net loan recoveries (losses) 2,005 554 - - (3,176 ) - (617 ) Total allowance for loan losses $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Allowance for Loan Losses For the Year Ended December 31, 2015 Commercial Commercial Construction Residential Consumer Unallocated Total (In thousands) Allowance for loan losses: Balance at beginning of period $ 5,460 $ 4,245 $ 654 $ 2,241 $ 9,827 $ 9,058 $ 31,485 Additions: Provision (reversal) 3,681 126 (33 ) (440 ) (239 ) (3,095 ) - Deductions: Chargeoffs (756 ) (449 ) (431 ) - (3,493 ) - (5,129 ) Recoveries 1,174 290 45 - 1,906 - 3,415 Net loan recoveries (losses) 418 (159 ) (386 ) - (1,587 ) - (1,714 ) Total allowance for loan losses $ 9,559 $ 4,212 $ 235 $ 1,801 $ 8,001 $ 5,963 $ 29,771
Schedule of Recorded Investment in Loans Evaluated for Impairment [Table Text Block]	Allowance for Loan Losses and Recorded Investment in Loans Evaluated for Impairment At December 31, 2017 Commercial Commercial Construction Residential Real Estate Consumer Installment and Other Unallocated Total (In thousands) Allowance for loan losses: Individually evaluated for impairment $ 4,814 $ 171 $ - $ - $ - $ - $ 4,985 Collectively evaluated for impairment 2,932 3,678 335 995 6,418 3,666 18,024 Purchased loans with evidence of credit deterioration - - - - - - - Total $ 7,746 $ 3,849 $ 335 $ 995 $ 6,418 $ 3,666 $ 23,009 Carrying value of loans: Individually evaluated for impairment $ 10,675 $ 14,234 $ - $ 208 $ - $ - $ 25,117 Collectively evaluated for impairment 325,291 553,769 5,649 64,975 312,406 - 1,262,090 Purchased loans with evidence of credit deterioration 30 581 - - 164 - 775 Total $ 335,996 $ 568,584 $ 5,649 $ 65,183 $ 312,570 $ - $ 1,287,982 Allowance for Loan Losses and Recorded Investment in Loans Evaluated for Impairment At December 31, 2016 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Unallocated Total (In thousands) Allowance for loan losses: Individually evaluated for impairment $ 5,048 $ - $ - $ - $ - $ - $ 5,048 Collectively evaluated for impairment 3,279 3,330 152 1,330 7,980 4,835 20,906 Purchased loans with evidence of credit deterioration - - - - - - - Total $ 8,327 $ 3,330 $ 152 $ 1,330 $ 7,980 $ 4,835 $ 25,954 Carrying value of loans: Individually evaluated for impairment $ 11,174 $ 12,706 $ - $ 835 $ - $ - $ 24,715 Collectively evaluated for impairment 343,494 528,957 2,555 86,889 365,236 - 1,327,131 Purchased loans with evidence of credit deterioration 29 508 - - 328 - 865 Total $ 354,697 $ 542,171 $ 2,555 $ 87,724 $ 365,564 $ - $ 1,352,711
Financing Receivable Credit Quality Indicators [Table Text Block]	Credit Risk Profile by Internally Assigned Grade At December 31, 2017 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Total (In thousands) Grade: Pass $ 324,185 $ 548,853 $ 5,649 $ 62,253 $ 310,429 $ 1,251,369 Substandard 11,811 19,731 - 2,930 1,370 35,842 Doubtful - - - - 1 1 Loss - - - - 770 770 Total $ 335,996 $ 568,584 $ 5,649 $ 65,183 $ 312,570 $ 1,287,982 Credit Risk Profile by Internally Assigned Grade At December 31, 2016 Commercial Commercial Real Estate Construction Residential Real Estate Consumer Installment and Other Total (In thousands) Grade: Pass $ 340,973 $ 515,045 $ 2,555 $ 84,384 $ 362,597 $ 1,305,554 Substandard 13,724 25,830 - 3,340 2,477 45,371 Doubtful - 1,296 - - 10 1,306 Loss - - - - 480 480 Total $ 354,697 $ 542,171 $ 2,555 $ 87,724 $ 365,564 $ 1,352,711
Past Due Financing Receivables [Table Text Block]	Summary of Loans by Delinquency and Nonaccrual Status Current and Accruing 30-59 Days Past Due and Accruing 60-89 Days Past Due and Accruing Past Due 90 Days or More and Accruing Nonaccrual Total Loans (In thousands) Commercial $ 334,908 $ 627 $ 164 $ - $ 297 $ 335,996 Commercial real estate 561,883 1,143 125 - 5,433 568,584 Construction 5,649 - - - - 5,649 Residential real estate 65,183 - - - - 65,183 Consumer installment and other 307,445 3,321 1,077 531 196 312,570 Total $ 1,275,068 $ 5,091 $ 1,366 $ 531 $ 5,926 $ 1,287,982 Summary of Loans by Delinquency and Nonaccrual Status Current and Accruing 30-59 Days Past Due and Accruing 60-89 Days Past Due and Accruing Past Due 90 Days or More and Accruing Nonaccrual Total Loans (In thousands) Commercial $ 353,497 $ 966 $ 40 $ - $ 194 $ 354,697 Commercial real estate 533,377 1,460 445 - 6,889 542,171 Construction 2,329 226 - - - 2,555 Residential real estate 86,098 528 37 - 1,061 87,724 Consumer installment and other 360,549 3,288 989 497 241 365,564 Total $ 1,335,850 $ 6,468 $ 1,511 $ 497 $ 8,385 $ 1,352,711
Impaired Financing Receivables [Table Text Block]	Impaired Loans 2017 2016 Recorded Unpaid Related Recorded Unpaid Related (In thousands) With no related allowance recorded: Commercial $ 1,212 $ 1,271 $ - $ 1,234 $ 1,303 $ - Commercial real estate 13,169 14,985 - 13,233 15,610 - Residential real estate 208 239 - 1,279 1,309 - Consumer installment and other 360 466 - 569 675 - Total with no related allowance recorded 14,949 16,961 - 16,315 18,897 - With an allowance recorded: Commercial 9,764 9,764 4,814 10,163 10,172 5,048 Commercial real estate 1,790 1,792 171 - - - Total with an allowance recorded 11,554 11,556 4,985 10,163 10,172 5,048 Total $ 26,503 $ 28,517 $ 4,985 $ 26,478 $ 29,069 $ 5,048
Impaired Financing Receivables Supplemental Schedule [Table Text Block]	Impaired Loans 2017 2016 2015 Average Recognized Average Recognized Average Recognized (In thousands) Commercial $ 11,156 $ 508 $ 12,923 $ 512 $ 12,631 $ 584 Commercial real estate 14,806 884 16,701 725 20,307 674 Construction - - 102 - 263 - Residential real estate 423 17 746 19 643 31 Consumer installment and other 415 20 473 25 739 25 Total $ 26,800 $ 1,429 $ 30,945 $ 1,281 $ 34,583 $ 1,314
Troubled Debt Restructurings on Financing Receivables [Table Text Block]	Troubled Debt Restructurings Period-End ($ in thousands) Commercial 7 $ 2,393 $ 1,085 $ 43 Commercial real estate 10 11,528 10,788 - Residential real estate 1 241 208 - Total 18 $ 14,162 $ 12,081 $ 43 Troubled Debt Restructurings Period-End ($ in thousands) Commercial 7 $ 2,719 $ 1,489 $ 113 Commercial real estate 10 11,257 10,673 - Residential real estate 1 241 219 - Total 18 $ 14,217 $ 12,381 $ 113 Troubled Debt Restructurings Period-End ($ in thousands) Commercial 6 $ 3,138 $ 2,802 $ 194 Commercial real estate 10 12,927 12,684 - Residential real estate 1 242 226 - Total 17 $ 16,307 $ 15,712 $ 194

Note 5 - Premises, Equipment 31

Note 5 - Premises, Equipment and Other Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Premises and Equipment [Table Text Block]	At December 31, Cost Accumulated Depreciation and Amortization Net Book Value (In thousands) 2017 Land $ 11,796 $ - $ 11,796 Building and improvements 41,641 (26,249 ) 15,392 Leasehold improvements 5,817 (4,790 ) 1,027 Furniture and equipment 22,284 (15,198 ) 7,086 Total $ 81,538 $ (46,237 ) $ 35,301 2016 Land $ 11,896 $ - $ 11,896 Building and improvements 40,992 (25,180 ) 15,812 Leasehold improvements 5,922 (4,599 ) 1,323 Furniture and equipment 21,874 (14,339 ) 7,535 Total $ 80,684 $ (44,118 ) $ 36,566
Schedule of Other Assets [Table Text Block]	At December 31, 2017 2016 (In thousands) Cost method equity investments: Federal Reserve Bank stock (1) $ 14,069 $ 14,069 Other investments 158 201 Total cost method equity investments 14,227 14,270 Life insurance cash surrender value 54,101 51,535 Net deferred tax asset 33,112 55,417 Limited partnership investments 10,119 12,591 Interest receivable 23,557 21,489 Prepaid assets 4,906 4,825 Other assets 18,428 11,597 Total other assets $ 158,450 $ 171,724
Schedule of Amounts Recognized in Net Income [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Investment loss included in pre-tax income $ 1,800 $ 2,475 $ 2,850 Valuation impairment included in pre-tax income 625 - - Tax credits recognized in provision for income taxes 1,850 2,286 2,650

Note 6 - Goodwill and Identif32

Note 6 - Goodwill and Identifiable Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Goodwill [Table Text Block]	At December 31, 2017 2016 (In thousands) Goodwill $ 121,673 $ 121,673
Schedule of Finite-Lived Intangible Assets [Table Text Block]	At December 31, 2017 2016 Gross Gross (In thousands) Core Deposit Intangibles $ 56,808 $ (52,987 ) $ 56,808 $ (50,074 ) Merchant Draft Processing Intangible 10,300 (10,271 ) 10,300 (10,107 ) Total Identifiable Intangible Assets $ 67,108 $ (63,258 ) $ 67,108 $ (60,181 )
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	Merchant (In thousands) For the Year Ended December 31, 2017 (actual) $ 2,913 $ 164 $ 3,077 Estimate for the Year Ended December 31, 2018 1,892 29 1,921 2019 538 - 538 2020 287 - 287 2021 269 - 269 2022 252 - 252

Note 7 - Deposits and Borrowe33

Note 7 - Deposits and Borrowed Funds (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Deposits [Table Text Block]	Deposits At December 31, 2017 2016 (In thousands) Noninterest-bearing $ 2,197,526 $ 2,089,443 Interest-bearing: Transaction 904,245 865,701 Savings 1,494,024 1,493,427 Time deposits less than $100 thousand 117,848 133,712 Time deposits $100 thousand through $250 thousand 76,578 84,925 Time deposits more than $250 thousand 37,392 37,533 Total deposits $ 4,827,613 $ 4,704,741
Schedule of Repurchase Agreements [Table Text Block]	Repurchase Agreements (Sweep) Remaining Contractual Maturity of the Agreements At December 31, 2017 2016 Repurchase agreements: (In thousands) Collateral securing borrowings: Securities of U.S. Government sponsored entities $ 74,173 $ 74,031 Agency residential MBS 58,251 63,277 Corporate securities 105,113 90,554 Total collateral carrying value $ 237,537 $ 227,862 Total short-term borrowed funds $ 58,471 $ 59,078
Borrowed Funds Highest Month End Balance [Table Text Block]	For the Years Ended December 31, 2017 2016 Highest Balance at Any Month-end (In thousands) Securities sold under repurchase agreements $ 82,126 $ 74,815

Note 8 - Shareholders' Equity (

Note 8 - Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]	Options Outstanding Options Exercisable At December 31, 2017 For the Year Ended December 31, 2017 At December 31, 2017 For the Year Ended December 31, 2017 Range of Exercise Price Number Outstanding Aggregate Intrinsic Value Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number Exercisable Aggregate Intrinsic Value Weighted Average Remaining Contractual Life Weighted Average Exercise Price (In thousands) (Years) (In thousands) (Years) $40 - 45 400 $ 6,798 7.5 $ 43 105 $ 1,751 6.9 $ 43 45 - 50 22 305 4.1 46 22 305 4.1 46 50 - 55 310 2,588 1.9 51 310 2,588 1.9 51 55 - 60 298 725 8.3 57 32 94 2.1 57 $40 - 60 1,030 $ 10,416 6.0 49 469 $ 4,738 3.1 49
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 Expected volatility (1) 20 % 22 % 20 % Expected life in years (2) 4.8 4.8 4.9 Risk-free interest rate (3) 1.97 % 1.41 % 1.36 % Expected dividend yield 3.28 % 4.49 % 3.64 % Fair value per award $ 8.27 $ 5.97 $ 5.46
Share-based Compensation, Stock Options, Activity [Table Text Block]	Shares Weighted Average Exercise Price Weighted Average Remaining Contractual Term (In thousands) (Years) Outstanding at January 1, 2017 1,273 $ 47.36 Granted 266 57.18 Exercised (509 ) 48.29 Forfeited or expired - N/A Outstanding at December 31, 2017 1,030 49.44 6.0 Exercisable at December 31, 2017 469 49.45 3.1
Schedule of Nonvested Share Activity [Table Text Block]	Shares Weighted (In thousands) Nonvested at January 1, 2017 553 $ 5.80 Granted 266 8.27 Vested (258 ) 5.78 Forfeited - N/A Nonvested at December 31, 2017 561 $ 6.98
Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]	2017 2016 (In thousands) Outstanding at January 1, 48 45 Granted 14 18 Issued upon vesting (13 ) (15 ) Forfeited - - Outstanding at December 31, 49 48

Note 9 - Regulatory Capital (Ta

Note 9 - Regulatory Capital (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block]	At December 31, 2017 Required To Be Well-capitalized Amount Ratio Amount Ratio Amount Ratio ($ in thousands) Common Equity Tier 1 Capital Company $ 479,259 15.36 % $ 179,377 5.75 % (1) N/A N/A Bank 383,796 12.50 % 176,568 5.75 % (1) $ 199,599 6.50 % Tier 1 Capital Company 479,259 15.36 % 226,170 7.25 % (1) N/A N/A Bank 383,796 12.50 % 222,630 7.25 % (1) 245,660 8.00 % Total Capital Company 504,576 16.17 % 288,562 9.25 % (1) N/A N/A Bank 415,113 13.52 % 284,045 9.25 % (1) 307,076 10.00 % Leverage Ratio (2) Company 479,259 8.86 % 216,280 4.000 % N/A N/A Bank 383,796 7.16 % 214,468 4.000 % 268,085 5.00 % At December 31, 2016 Required To Be Well-capitalized Amount Ratio Amount Ratio Amount Ratio ($ in thousands) Common Equity Tier 1 Capital Company $ 443,574 14.85 % $ 153,126 5.125 % (3) N/A N/A Bank 344,739 11.70 % 150,982 5.125 % (3) $ 191,489 6.50 % Tier 1 Capital Company 443,574 14.85 % 197,944 6.625 % (3) N/A N/A Bank 344,739 11.70 % 195,172 6.625 % (3) 235,680 8.00 % Total Capital Company 476,595 15.95 % 257,700 8.625 % (3) N/A N/A Bank 383,572 13.02 % 254,092 8.625 % (3) 294,600 10.00 % Leverage Ratio (2) Company 443,574 8.46 % 209,702 4.000 % N/A N/A Bank 344,739 6.63 % 208,005 4.000 % 260,006 5.00 %

Note 10 - Income Taxes (Tables)

Note 10 - Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	At December 31, 2017 2016 (In thousands) Deferred tax asset Allowance for credit losses $ 7,349 $ 11,801 State franchise taxes 1,871 2,679 AMT carryforward 1,752 - Securities available for sale 8,586 7,283 Deferred compensation 5,279 8,043 Real estate owned 553 756 Purchased assets and assumed liabilities 1,111 3,026 Post-retirement benefits 526 903 Employee benefit accruals 2,066 3,399 VISA Class B shares 96 137 Limited partnership investments 57 86 Impaired capital assets 3,056 18,465 Accrued liabilities 1,609 967 Premises and equipment 299 577 Other 520 724 Total deferred tax asset 34,730 58,846 Deferred tax liability Net deferred loan fees 281 346 Intangible assets 1,247 2,955 Other 90 128 Total deferred tax liability 1,618 3,429 Net deferred tax asset $ 33,112 $ 55,417
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Current income tax expense: Federal $ 1,778 $ 16,258 $ 9,647 State 7,810 7,292 6,738 Total current 9,588 23,550 16,385 Deferred income tax (benefit) expense: Federal 14,461 (2,604 ) 1,643 State 783 158 (109 ) Total deferred 15,244 (2,446 ) 1,534 Adjustment of net deferred tax asset for enacted changes in tax rates: Federal 12,315 - - State - - - Total adjustments 12,315 $ - $ - Provision for income taxes $ 37,147 $ 21,104 $ 17,919
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Federal income taxes due at statutory rate $ 30,509 $ 27,985 $ 26,835 Reductions in income taxes resulting from: Interest on state and municipal securities and loans not taxable for (7,794 ) (8,382 ) (9,046 ) State franchise taxes, net of federal income tax benefit 5,586 4,843 4,309 Re-measurement of net deferred tax asset due to enactment of new federal tax rate 12,315 - - Stock compensation deduction in excess of book expense (583 ) - - Tax credits (1,850 ) (2,286 ) (2,600 ) Dividend received deduction (60 ) (52 ) (45 ) Cash value life insurance (603 ) (607 ) (599 ) Other (373 ) (397 ) (935 ) Provision for income taxes $ 37,147 $ 21,104 $ 17,919
Summary of Income Tax Contingencies [Table Text Block]	2017 2016 (In thousands) Balance at January 1, $ 1,099 $ 1,243 Additions for tax positions taken in the current period - - Reductions for tax positions taken in the current period - - Additions for tax positions taken in prior years - - Reductions for tax positions taken in prior years - (144 ) Decrease related to settlements with taxing authorities (190 ) - Decrease as a result of a lapse in statute of limitations - - Balance at December 31, $ 909 $ 1,099

Note 11 - Fair Value Measurem37

Note 11 - Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Fair Value, Assets Measured on Recurring Basis [Table Text Block]	At December 31, 2017 Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs (In thousands) Securities of U.S. Government sponsored entities $ 119,319 $ - $ 119,319 $ - Agency residential MBS 767,706 - 767,706 - Non-agency residential MBS 154 - 154 - Agency commercial MBS 2,219 - 2,219 - Securities of U.S. Government entities 1,590 - 1,590 - Obligations of states and political subdivisions 185,221 - 185,221 - Corporate securities 1,115,498 - 1,115,498 - Other securities 1,800 - 1,800 - Total securities available for sale $ 2,193,507 $ - $ 2,193,507 $ - At December 31, 2016 Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs (In thousands) Securities of U.S. Government sponsored entities $ 138,660 $ - $ 138,660 $ - Agency residential MBS 691,499 - 691,499 - Non-agency residential MBS 271 - 271 - Securities of U.S. Government entities 2,025 - 2,025 - Obligations of states and political subdivisions 183,411 - 183,411 - Asset-backed securities 695 - 695 - FHLMC and FNMA stock 10,869 17 10,852 - Corporate securities 860,857 - 860,857 - Other securities 2,471 656 1,815 - Total securities available for sale $ 1,890,758 $ 673 $ 1,890,085 $ -
Fair Value Measurements, Nonrecurring [Table Text Block]	For the Year Ended At December 31, 2017 December 31, 2017 Carrying Value Level 1 Level 2 Level 3 Total Losses (In thousands) Other real estate owned $ 1,426 $ - $ - $ 1,426 $ (219 ) Impaired loans: Commercial 4,950 - - 4,950 - Commercial real estate 5,904 - - 5,904 - Total assets measured at fair value on a nonrecurring basis $ 12,280 $ - $ - $ 12,280 $ (219 ) For the Year Ended At December 31, 2016 December 31, 2016 Carrying Value Level 1 Level 2 Level 3 Total Losses (In thousands) Other real estate owned $ 3,095 $ - $ - $ 3,095 $ (705 ) Impaired loans: Commercial 5,115 - - 5,115 - Commercial real estate 4,410 - - 4,410 - Total assets measured at fair value on a nonrecurring basis $ 12,620 $ - $ - $ 12,620 $ (705 )
Fair Value, by Balance Sheet Grouping [Table Text Block]	At December 31, 2017 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: (In thousands) Cash and due from banks $ 575,002 $ 575,002 $ 575,002 $ - $ - Investment securities held to maturity 1,158,864 1,155,342 - 1,155,342 - Loans 1,264,973 1,257,811 - - 1,257,811 Financial Liabilities: Deposits $ 4,827,613 $ 4,824,586 $ - $ 4,595,795 $ 228,791 Short-term borrowed funds 58,471 58,471 - 58,471 - At December 31, 2016 Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: (In thousands) Cash and due from banks $ 462,271 $ 462,271 $ 462,271 $ - $ - Investment securities held to maturity 1,346,312 1,340,741 - 1,340,741 - Loans 1,326,757 1,337,774 - - 1,337,774 Financial Liabilities: Deposits $ 4,704,741 $ 4,702,797 $ - $ 4,448,571 $ 254,226 Short-term borrowed funds 59,078 59,078 - 59,078 -

Note 12 - Lease Commitments (Ta

Note 12 - Lease Commitments (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]	Minimum (In thousands) 2018 $ 6,481 2019 4,882 2020 3,143 2021 1,462 2022 732 Thereafter 825 Total minimum lease payments $ 17,525

Note 14 - Retirement Benefit 39

Note 14 - Retirement Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Net Benefit Costs [Table Text Block]	At December 31, 2017 2016 2015 (In thousands) Service benefit $ (311 ) $ (153 ) $ (202 ) Interest cost 95 108 106 Amortization of unrecognized transition obligation 61 61 61 Net periodic (benefit) cost $ (155 ) $ 16 $ (35 ) Amortization of unrecognized transition obligation, net of tax (34 ) (36 ) (36 ) Total recognized in net periodic (benefit) cost and accumulated other comprehensive income $ (189 ) $ (20 ) $ (71 )
Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets [Table Text Block]	At December 31, 2017 2016 2015 Change in benefit obligation (In thousands) Benefit obligation at beginning of year $ 2,319 $ 2,522 $ 2,782 Service benefit $ (311 ) $ (153 ) (202 ) Interest cost 95 108 106 Benefits paid (145 ) (158 ) (164 ) Benefit obligation at end of year $ 1,958 $ 2,319 $ 2,522 Accumulated post-retirement benefit obligation attributable to: Retirees $ 1,575 $ 1,705 $ 1,695 Fully eligible participants 382 606 809 Other 1 8 18 Total $ 1,958 $ 2,319 $ 2,522 Fair value of plan assets - - - Accumulated post-retirement benefit obligation in excess of plan assets $ 1,958 $ 2,319 $ 2,522
Schedule of Assumptions Used [Table Text Block]	At December 31, 2017 2016 2015 Weighted-average assumptions used to determine benefit obligations Discount rate 3.70 % 4.10 % 4.30 % Weighted-average assumptions used to determine net periodic benefit cost Discount rate 4.10 % 4.30 % 3.80 %
Schedule of Expected Benefit Payments [Table Text Block]	Estimated future benefit payments (In thousands) 2018 $ 138 2019 131 2020 124 2021 118 2022 112 Years 2023-2027 482

Note 15 - Related Party Trans40

Note 15 - Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Related Party Transactions [Table Text Block]	2017 2016 (In thousands) Balance at January 1, $ 867 $ 911 Originations - - Principal reductions $ (245 ) (44 ) Balance at December 31, $ 622 $ 867 Percent of total loans outstanding. 0.05 % 0.06 %

Note 17 - Other Comprehensive41

Note 17 - Other Comprehensive Income (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Comprehensive Income (Loss) [Table Text Block]	2017 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (3,767 ) $ 1,585 $ (2,182 ) Reclassification of gains included in net income (7,955 ) 3,345 (4,610 ) Net unrealized losses arising during the year (11,722 ) 4,930 (6,792 ) Post-retirement benefit obligation 59 (25 ) 34 Other comprehensive loss $ (11,663 ) $ 4,905 $ (6,758 ) 2016 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (18,610 ) $ 7,825 $ (10,785 ) Reclassification of gains (losses) included in net income - - - Net unrealized losses arising during the year (18,610 ) 7,825 (10,785 ) Post-retirement benefit obligation 61 (25 ) 36 Other comprehensive loss $ (18,549 ) $ 7,800 $ (10,749 ) 2015 Before tax Tax effect Net of tax (In thousands) Securities available for sale: Net unrealized losses arising during the year $ (8,028 ) $ 3,375 $ (4,653 ) Reclassification of gains (losses) included in net income - - - Net unrealized losses arising during the year (8,028 ) 3,375 (4,653 ) Post-retirement benefit obligation 61 (25 ) 36 Other comprehensive loss $ (7,967 ) $ 3,350 $ (4,617 )
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Post-retirement Benefit Obligation Net Unrealized Gains (losses) on Securities Accumulated Other Comprehensive Income (loss) (In thousands) Balance, December 31, 2014 $ (106 ) $ 5,398 $ 5,292 Net change 36 (4,653 ) (4,617 ) Balance, December 31, 2015 (70 ) 745 675 Net change 36 (10,785 ) (10,749 ) Balance, December 31, 2016 (34 ) (10,040 ) (10,074 ) Net change 34 (6,792 ) (6,758 ) Balance, December 31, 2017 $ - $ (16,832 ) $ (16,832 )

Note 18 - Earnings Per Common42

Note 18 - Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands, except per share data) Net income (numerator) $ 50,025 $ 58,853 $ 58,753 Basic earnings per common share Weighted average number of common shares outstanding - basic (denominator) 26,291 25,612 25,555 Basic earnings per common share $ 1.90 $ 2.30 $ 2.30 Diluted earnings per common share Weighted average number of common shares outstanding - basic 26,291 25,612 25,555 Add common stock equivalents for options 128 66 22 Weighted average number of common shares outstanding - diluted (denominator) 26,419 25,678 25,577 Diluted earnings per common share $ 1.89 $ 2.29 $ 2.30

Note 19 - Westamerica Bancorp43

Note 19 - Westamerica Bancorporation (Parent Company Only Condensed Financial Information) (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Statements of Income and Comprehensive Income, Parent Only [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Dividends from subsidiaries $ 12,728 $ 56,824 $ 68,981 Interest income 43 25 10 Other income 8,590 8,315 8,411 Total income 21,361 65,164 77,402 Interest on borrowings - - 1 Salaries and benefits 7,163 7,079 6,291 Other expense 3,416 3,290 3,424 Total expense 10,579 10,369 9,716 Income before taxes and equity in undistributed income of subsidiaries 10,782 54,795 67,686 Income tax benefit 241 1,025 803 Earnings of subsidiaries greater (less) than subsidiary dividends 39,002 3,033 (9,736 ) Net income 50,025 58,853 58,753 Other comprehensive loss, net of tax (6,758 ) (10,749 ) (4,617 ) Comprehensive income $ 43,267 $ 48,104 $ 54,136
Balance Sheets Parent Only [Table Text Block]	At December 31, 2017 2016 (In thousands) Assets Cash $ 53,409 $ 64,054 Investment securities available for sale - 656 Investment in Westamerica Bank 500,776 468,172 Investment in non-bank subsidiaries 455 455 Premises and equipment, net 9,639 9,165 Accounts receivable from Westamerica Bank 538 522 Other assets 40,547 34,077 Total assets $ 605,364 $ 577,101 Liabilities Accounts payable to Westamerica Bank $ 92 $ 705 Other liabilities 15,033 15,029 Total liabilities 15,125 15,734 Shareholders' equity 590,239 561,367 Total liabilities and shareholders' equity $ 605,364 $ 577,101
Statement of Cash Flows Parent Only [Table Text Block]	For the Years Ended December 31, 2017 2016 2015 (In thousands) Operating Activities Net income $ 50,025 $ 58,853 $ 58,753 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation and amortization 319 305 326 Decrease (increase) in accounts receivable from affiliates (16 ) 299 (217 ) Insurance premiums paid (704 ) (683 ) (637 ) Increase in other assets (1,499 ) (1,257 ) (1,076 ) Stock option compensation expense 1,824 1,494 1,272 Tax benefit (increase) decrease upon exercise of stock options and expiration of stock options - (394 ) 1,284 Provision (benefit) for deferred income tax (3,971 ) 1,983 (491 ) Increase in other liabilities 202 1,392 743 Earnings of subsidiaries (greater) less than subsidiary dividends (39,002 ) (3,033 ) 9,736 Gain on sales of property and equipment (793 ) (79 ) (39 ) Net Cash Provided by Operating Activities 6,385 58,880 69,654 Investing Activities Purchases of premises and equipment - - - Net Cash Provided by Investing Activities - - - Financing Activities Exercise of stock options/issuance of shares 24,583 24,031 4,848 Taxes paid by withholding shares for tax purposes - (356 ) (357 ) Tax benefit increase (decrease) upon exercise of stock options and expiration of stock options - 394 (1,284 ) Retirement of common stock (314 ) (5,424 ) (14,735 ) Dividends (41,299 ) (39,924 ) (39,124 ) Net Cash Used in Financing Activities (17,030 ) (21,279 ) (50,652 ) Net change in cash (10,645 ) 37,601 19,002 Cash at Beginning of Period 64,054 26,453 7,451 Cash at End of Period $ 53,409 $ 64,054 $ 26,453 Supplemental Cash Flow Disclosures: Supplemental disclosure of cash flow activities: Interest paid for the period $ - $ - $ 1 Income tax payments for the period 17,351 19,264 17,666

Note 20 - Quarterly Financial44

Note 20 - Quarterly Financial Information (Tables)	12 Months Ended
	Dec. 31, 2017
Notes Tables
Quarterly Financial Information [Table Text Block]	For the Three Months Ended March 31, June 30, September 30, December 31, (In thousands, expect per share data and 2017 Interest and loan fee income $ 33,324 $ 33,163 $ 33,145 $ 34,204 Net interest income 32,844 32,687 32,672 33,733 (Reversal of) provision for loan losses - (1,900 ) - - Noninterest income 11,657 12,123 12,548 20,300 Noninterest expense 24,615 24,396 24,114 30,167 Income before taxes 19,886 22,314 21,106 23,866 Net income 15,049 15,799 15,017 4,160 Basic earnings per common share 0.58 0.60 0.57 0.16 Diluted earnings per common share 0.57 0.60 0.57 0.16 Dividends paid per common share 0.39 0.39 0.39 0.40 Price range, common stock 54.12 - 64.07 51.31 - 57.78 49.54 - 59.54 53.96 - 63.03 2016 Interest and loan fee income $ 33,647 $ 33,727 $ 33,468 $ 33,209 Net interest income 33,095 33,186 32,945 32,709 (Reversal of) provision for loan losses - - (3,200 ) - Noninterest income 11,729 11,702 11,598 11,545 Noninterest expense 25,858 25,229 26,088 24,577 Income before taxes 18,966 19,659 21,655 19,677 Net income 14,226 14,546 15,628 14,453 Basic earnings per common share 0.56 0.57 0.61 0.56 Diluted earnings per common share 0.56 0.57 0.61 0.56 Dividends paid per common share 0.39 0.39 0.39 0.39 Price range, common stock 40.72 - 49.63 45.86 - 51.53 46.61 - 50.96 48.20 - 65.34 2015 Interest and loan fee income $ 33,917 $ 34,425 $ 34,299 $ 33,888 Net interest income 33,258 33,808 33,714 33,325 Provision for loan losses - - - - Noninterest income 12,300 12,269 11,993 11,305 Noninterest expense 26,727 26,896 26,173 25,504 Income before taxes 18,831 19,181 19,534 19,126 Net income 14,557 14,761 14,857 14,578 Basic earnings per common share 0.57 0.58 0.58 0.57 Diluted earnings per common share 0.57 0.58 0.58 0.57 Dividends paid per common share 0.38 0.38 0.38 0.39 Price range, common stock 40.68 - 48.44 42.70 - 51.69 43.00 - 51.90 42.96 - 49.64

Note 1 - Business and Account45

Note 1 - Business and Accounting Policies (Details Textual) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loans and Leases Receivable, Days Before Nonaccrual Status	90 days
Loans and Leases Receivable, Certain Consumer Loans and Auto Receivables, Days Before Chargeoff	120 days
Financing Receivable, Impairment Evaluation Criterion, Minimum Outstanding Principal Balance	$ 500
FDIC Indemnification Rate	80.00%
FDIC Indemnification Rate, Duration of Interest Covered	90 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	509
Excess Tax Deduction Exceeding Related Share-based Compensation, Operating Activities	$ 1,667
Income Tax Expense (Benefit)	$ 37,147	$ 21,104	$ 17,919
Percentage of Revenue Out of Scope of ASU 2014-09	73.00%
Available-for-sale Securities	$ 2,193,507	$ 1,890,758
Operating Leases, Future Minimum Payments Due	17,525
Equity Securities [Member]
Available-for-sale Securities	2,000
Accounting Standards Update 2016-09 [Member]
Income Tax Expense (Benefit)	$ (698)
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	15 years
Land and Land Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life	20 years
Land and Land Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life	50 years
Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life	3 years
Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life	20 years

Note 2 - Investment Securitie46

Note 2 - Investment Securities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Gain (Loss) on Sale of Equity Investments	$ 7,955
High Risk Collateralized Mortgage Obligations	0	0
Pledged Financial Instruments, Not Separately Reported, Securities	715,774	$ 768,845
FHLMC and FNMA Stock [Member]
Proceeds from Sale of Available-for-sale Securities, Debt	8,704
Gain (Loss) on Sale of Equity Investments	$ 7,955

Note 2 - Investment Securitie47

Note 2 - Investment Securities - Amortized Cost, Unrealized Gains and Losses, and Estimated Fair Value of Available for Sale Investment Securities Portfolio (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Investment securities available for sale, amortized cost		$ 2,222,551	$ 1,908,079
Investment securities available for sale, gross unrealized gains		5,424	18,494
Investment securities available for sale, gross unrealized losses		(34,468)	(35,815)
Investment securities available for sale		2,193,507	1,890,758
US Government-sponsored Enterprises Debt Securities [Member]
Investment securities available for sale, amortized cost		122,285	141,599
Investment securities available for sale, gross unrealized gains		1	35
Investment securities available for sale, gross unrealized losses		(2,967)	(2,974)
Investment securities available for sale		119,319	138,660
Agency Residential MBS [Member]
Investment securities available for sale, amortized cost		787,679	711,623
Investment securities available for sale, gross unrealized gains		522	921
Investment securities available for sale, gross unrealized losses		(20,495)	(21,045)
Investment securities available for sale		767,706	691,499
Non-agency Residential MBS [Member]
Investment securities available for sale, amortized cost		153	272
Investment securities available for sale, gross unrealized gains		1
Investment securities available for sale, gross unrealized losses			(1)
Investment securities available for sale		154	271
Agency Commercial MBS [Member]
Investment securities available for sale, amortized cost		2,244
Investment securities available for sale, gross unrealized gains
Investment securities available for sale, gross unrealized losses		(25)
Investment securities available for sale		2,219
US Government Agencies Debt Securities [Member]
Investment securities available for sale, amortized cost		1,612	2,041
Investment securities available for sale, gross unrealized gains
Investment securities available for sale, gross unrealized losses		(22)	(16)
Investment securities available for sale		1,590	2,025
US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale, amortized cost		182,907	182,230
Investment securities available for sale, gross unrealized gains		3,796	5,107
Investment securities available for sale, gross unrealized losses		(1,482)	(3,926)
Investment securities available for sale		185,221	183,411
Asset-backed Securities [Member]
Investment securities available for sale, amortized cost			696
Investment securities available for sale, gross unrealized gains
Investment securities available for sale, gross unrealized losses			(1)
Investment securities available for sale			695
Domestic Corporate Debt Securities [Member]
Investment securities available for sale, amortized cost		1,123,671	866,835
Investment securities available for sale, gross unrealized gains		1,104	1,690
Investment securities available for sale, gross unrealized losses		(9,277)	(7,668)
Investment securities available for sale		1,115,498	860,857
FHLMC and FNMA Stock [Member]
Investment securities available for sale, amortized cost	[1],[2]		749
Investment securities available for sale, gross unrealized gains	[1],[2]		10,120
Investment securities available for sale, gross unrealized losses	[1],[2]
Investment securities available for sale	[1],[2]		10,869
Other Securities [Member]
Investment securities available for sale, amortized cost		2,000	2,034
Investment securities available for sale, gross unrealized gains			621
Investment securities available for sale, gross unrealized losses		(200)	(184)
Investment securities available for sale		$ 1,800	$ 2,471
[1]	Federal Home Loan Mortgage Corporation
[2]	Federal National Mortgage Association

Note 2 - Investment Securitie48

Note 2 - Investment Securities - Amortized Cost, Unrealized Gains and Losses, and Estimated Market Value of Held to Maturity Investment Securities Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment securities held to maturity, amortized cost	$ 1,158,864	$ 1,346,312
Investment securities held to maturity, gross unrecognized gains	8,412	7,241
Investment securities held to maturity, gross unrecognized losses	(11,934)	(12,812)
Investment securities held to maturity, fair values	1,155,342	1,340,741
Agency Residential MBS [Member]
Investment securities held to maturity, amortized cost	545,883	668,235
Investment securities held to maturity, gross unrecognized gains	606	1,122
Investment securities held to maturity, gross unrecognized losses	(9,850)	(8,602)
Investment securities held to maturity, fair values	536,639	660,755
US Government-sponsored Enterprises Debt Securities [Member]
Investment securities held to maturity, amortized cost		581
Investment securities held to maturity, gross unrecognized gains		1
Investment securities held to maturity, gross unrecognized losses
Investment securities held to maturity, fair values		582
Non-agency Residential MBS [Member]
Investment securities held to maturity, amortized cost	4,462	5,370
Investment securities held to maturity, gross unrecognized gains	70	76
Investment securities held to maturity, gross unrecognized losses
Investment securities held to maturity, fair values	4,532	5,446
Agency Commercial MBS [Member]
Investment securities held to maturity, amortized cost	9,041	9,332
Investment securities held to maturity, gross unrecognized gains		11
Investment securities held to maturity, gross unrecognized losses	(66)	(143)
Investment securities held to maturity, fair values	8,975	9,200
US States and Political Subdivisions Debt Securities [Member]
Investment securities held to maturity, amortized cost	599,478	662,794
Investment securities held to maturity, gross unrecognized gains	7,736	6,031
Investment securities held to maturity, gross unrecognized losses	(2,018)	(4,067)
Investment securities held to maturity, fair values	$ 605,196	$ 664,758

Note 2 - Investment Securitie49

Note 2 - Investment Securities - Amortized Cost and Estimated Market Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment securities available for sale, amortized cost, 1 year or less	$ 193,337	$ 154,693
Investment securities available for sale, fair value, 1 year or less	193,385	154,835
Investment securities held to maturity, amortized cost, 1 year or less	50,295	14,961
Investment securities held to maturity, fair value, 1 year or less	51,105	15,639
Investment securities available for sale, amortized cost, over 1 to 5 years	1,031,807	750,834
Investment securities available for sale, fair value, over 1 to 5 years	1,023,047	745,219
Investment securities held to maturity, amortized cost, over 1 to 5 years	269,050	292,024
Investment securities held to maturity, fair value, over 1 to 5 years	269,471	292,062
Investment securities available for sale, amortized cost, over 5 to 10 years	159,266	238,077
Investment securities available for sale, fair value, over 5 to 10 years	160,042	239,153
Investment securities held to maturity, amortized cost, over 5 to 10 years	277,170	318,580
Investment securities held to maturity, fair value, over 5 to 10 years	281,546	319,587
Investment securities available for sale, amortized cost, over 10 years	46,065	47,756
Investment securities available for sale, fair value, over 10 years	45,154	44,416
Investment securities held to maturity, amortized cost, over 10 years	2,963	37,810
Investment securities held to maturity, fair value, over 10 years	3,074	38,052
Investment securities available for sale, amortized cost, subtotal	1,430,475	1,191,360
Investment securities available for sale, fair value, subtotal	1,421,628	1,183,623
Investment securities held to maturity, amortized cost, subtotal	599,478	663,375
Investment securities held to maturity, fair value, subtotal	605,196	665,340
Investment securities available for sale, amortized cost	2,222,551	1,908,079
Investment securities available for sale	2,193,507	1,890,758
Investment securities held to maturity, amortized cost	1,158,864	1,346,312
Investment securities held to maturity, fair values	1,155,342	1,340,741
Mortgage Backed Securities [Member]
Investment securities available for sale, amortized cost	790,076	713,936
Investment securities available for sale, fair value	770,079	693,795
Investment securities held to maturity, amortized cost	559,386	682,937
Investment securities held to maturity, fair value	550,146	675,401
Other Securities [Member]
Investment securities available for sale, amortized cost	2,000	2,783
Investment securities available for sale, fair value	1,800	13,340
Investment securities held to maturity, amortized cost
Investment securities held to maturity, fair value
Investment securities available for sale, amortized cost	2,000	2,034
Investment securities available for sale	$ 1,800	$ 2,471

Note 2 - Investment Securitie50

Note 2 - Investment Securities - Gross Unrealized Losses, Investment Securities Portfolio (Details) $ in Thousands	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Available for sale securities, less than 12 months, number of investment positions	125	129
Available for sale securities, less than 12 months, fair value	$ 834,335	$ 1,086,159
Available for sale securities, less than 12 months, unrealized losses	$ (5,803)	$ (29,934)
Available for sale securities, 12 months or longer, number of investment positions	136	61
Available for sale securities, 12 months or longer, fair value	$ 972,348	$ 223,446
Available for sale securities, 12 months or longer, unrealized losses	$ (28,665)	$ (5,881)
Available for sale securities, total, number of investment positions	261	190
Available for sale securities, total, fair value	$ 1,806,683	$ 1,309,605
Available for sale securities, total, unrealized losses	$ (34,468)	$ (35,815)
Held to Maturity securities, less than 12 months, number of investment positions	162	361
Held to Maturity securities, less than 12 months, fair value	$ 163,163	$ 842,372
Held to Maturity securities, less than 12 months, unrecognized losses	$ (758)	$ (11,995)
Held to Maturity securities, 12 months or longer, number of investment positions	125	16
Held to Maturity securities, 12 months or longer, fair value	$ 545,816	$ 30,820
Held to Maturity securities, 12 months or longer, unrecognized losses	$ (11,176)	$ (817)
Held to Maturity securities, total, number of investment positions	287	377
Held to Maturity securities, total, fair value	$ 708,979	$ 873,192
Held to Maturity securities, total, unrecognized losses	$ (11,934)	$ (12,812)
US Government-sponsored Enterprises Debt Securities [Member]
Available for sale securities, less than 12 months, number of investment positions	1	8
Available for sale securities, less than 12 months, fair value	$ 996	$ 117,227
Available for sale securities, less than 12 months, unrealized losses	$ (2)	$ (2,974)
Available for sale securities, 12 months or longer, number of investment positions	8
Available for sale securities, 12 months or longer, fair value	$ 117,252
Available for sale securities, 12 months or longer, unrealized losses	$ (2,965)
Available for sale securities, total, number of investment positions	9	8
Available for sale securities, total, fair value	$ 118,248	$ 117,227
Available for sale securities, total, unrealized losses	$ (2,967)	$ (2,974)
Agency Residential MBS [Member]
Available for sale securities, less than 12 months, number of investment positions	7	21
Available for sale securities, less than 12 months, fair value	$ 238,554	$ 524,269
Available for sale securities, less than 12 months, unrealized losses	$ (1,501)	$ (16,494)
Available for sale securities, 12 months or longer, number of investment positions	51	28
Available for sale securities, 12 months or longer, fair value	$ 516,711	$ 122,901
Available for sale securities, 12 months or longer, unrealized losses	$ (18,994)	$ (4,551)
Available for sale securities, total, number of investment positions	58	49
Available for sale securities, total, fair value	$ 755,265	$ 647,170
Available for sale securities, total, unrealized losses	$ (20,495)	$ (21,045)
Held to Maturity securities, less than 12 months, number of investment positions	15	66
Held to Maturity securities, less than 12 months, fair value	$ 30,218	$ 569,876
Held to Maturity securities, less than 12 months, unrecognized losses	$ (201)	$ (8,285)
Held to Maturity securities, 12 months or longer, number of investment positions	65	3
Held to Maturity securities, 12 months or longer, fair value	$ 479,775	$ 10,480
Held to Maturity securities, 12 months or longer, unrecognized losses	$ (9,649)	$ (317)
Held to Maturity securities, total, number of investment positions	80	69
Held to Maturity securities, total, fair value	$ 509,993	$ 580,356
Held to Maturity securities, total, unrecognized losses	$ (9,850)	$ (8,602)
Agency Commercial MBS [Member]
Available for sale securities, less than 12 months, number of investment positions	2
Available for sale securities, less than 12 months, fair value	$ 2,219
Available for sale securities, less than 12 months, unrealized losses	$ (25)
Available for sale securities, 12 months or longer, number of investment positions
Available for sale securities, 12 months or longer, fair value
Available for sale securities, 12 months or longer, unrealized losses
Available for sale securities, total, number of investment positions	2
Available for sale securities, total, fair value	$ 2,219
Available for sale securities, total, unrealized losses	$ (25)
Held to Maturity securities, less than 12 months, number of investment positions	1
Held to Maturity securities, less than 12 months, fair value	$ 1,913
Held to Maturity securities, less than 12 months, unrecognized losses	$ (4)
Held to Maturity securities, 12 months or longer, number of investment positions	1	1
Held to Maturity securities, 12 months or longer, fair value	$ 7,062	$ 7,214
Held to Maturity securities, 12 months or longer, unrecognized losses	$ (62)	$ (143)
Held to Maturity securities, total, number of investment positions	2	1
Held to Maturity securities, total, fair value	$ 8,975	$ 7,214
Held to Maturity securities, total, unrecognized losses	$ (66)	$ (143)
Non-agency Residential MBS [Member]
Available for sale securities, less than 12 months, number of investment positions	1	2
Available for sale securities, less than 12 months, fair value	$ 1	$ 246
Available for sale securities, less than 12 months, unrealized losses		$ (1)
Available for sale securities, 12 months or longer, number of investment positions
Available for sale securities, 12 months or longer, fair value
Available for sale securities, 12 months or longer, unrealized losses
Available for sale securities, total, number of investment positions	1	2
Available for sale securities, total, fair value	$ 1	$ 246
Available for sale securities, total, unrealized losses		$ (1)
US States and Political Subdivisions Debt Securities [Member]
Available for sale securities, less than 12 months, number of investment positions	50	43
Available for sale securities, less than 12 months, fair value	$ 21,453	$ 57,989
Available for sale securities, less than 12 months, unrealized losses	$ (228)	$ (3,905)
Available for sale securities, 12 months or longer, number of investment positions	35	3
Available for sale securities, 12 months or longer, fair value	$ 52,071	$ 1,117
Available for sale securities, 12 months or longer, unrealized losses	$ (1,254)	$ (21)
Available for sale securities, total, number of investment positions	85	46
Available for sale securities, total, fair value	$ 73,524	$ 59,106
Available for sale securities, total, unrealized losses	$ (1,482)	$ (3,926)
Held to Maturity securities, less than 12 months, number of investment positions	146	295
Held to Maturity securities, less than 12 months, fair value	$ 131,032	$ 272,496
Held to Maturity securities, less than 12 months, unrecognized losses	$ (553)	$ (3,710)
Held to Maturity securities, 12 months or longer, number of investment positions	59	12
Held to Maturity securities, 12 months or longer, fair value	$ 58,979	$ 13,126
Held to Maturity securities, 12 months or longer, unrecognized losses	$ (1,465)	$ (357)
Held to Maturity securities, total, number of investment positions	205	307
Held to Maturity securities, total, fair value	$ 190,011	$ 285,622
Held to Maturity securities, total, unrecognized losses	$ (2,018)	$ (4,067)
US Government Agencies Debt Securities [Member]
Available for sale securities, less than 12 months, number of investment positions		2
Available for sale securities, less than 12 months, fair value		$ 1,253
Available for sale securities, less than 12 months, unrealized losses		$ (9)
Available for sale securities, 12 months or longer, number of investment positions	3	1
Available for sale securities, 12 months or longer, fair value	$ 1,590	$ 772
Available for sale securities, 12 months or longer, unrealized losses	$ (22)	$ (7)
Available for sale securities, total, number of investment positions	3	3
Available for sale securities, total, fair value	$ 1,590	$ 2,025
Available for sale securities, total, unrealized losses	$ (22)	$ (16)
Asset-backed Securities [Member]
Available for sale securities, less than 12 months, number of investment positions
Available for sale securities, less than 12 months, fair value
Available for sale securities, less than 12 months, unrealized losses
Available for sale securities, 12 months or longer, number of investment positions		1
Available for sale securities, 12 months or longer, fair value		$ 695
Available for sale securities, 12 months or longer, unrealized losses		$ (1)
Available for sale securities, total, number of investment positions		1
Available for sale securities, total, fair value		$ 695
Available for sale securities, total, unrealized losses		$ (1)
Domestic Corporate Debt Securities [Member]
Available for sale securities, less than 12 months, number of investment positions	64	53
Available for sale securities, less than 12 months, fair value	$ 571,112	$ 385,175
Available for sale securities, less than 12 months, unrealized losses	$ (4,047)	$ (6,551)
Available for sale securities, 12 months or longer, number of investment positions	38	27
Available for sale securities, 12 months or longer, fair value	$ 282,924	$ 96,145
Available for sale securities, 12 months or longer, unrealized losses	$ (5,230)	$ (1,117)
Available for sale securities, total, number of investment positions	102	80
Available for sale securities, total, fair value	$ 854,036	$ 481,320
Available for sale securities, total, unrealized losses	$ (9,277)	$ (7,668)
Other Securities [Member]
Available for sale securities, less than 12 months, number of investment positions
Available for sale securities, less than 12 months, fair value
Available for sale securities, less than 12 months, unrealized losses
Available for sale securities, 12 months or longer, number of investment positions	1	1
Available for sale securities, 12 months or longer, fair value	$ 1,800	$ 1,816
Available for sale securities, 12 months or longer, unrealized losses	$ (200)	$ (184)
Available for sale securities, total, number of investment positions	1	1
Available for sale securities, total, fair value	$ 1,800	$ 1,816
Available for sale securities, total, unrealized losses	$ (200)	$ (184)

Note 2 - Investment Securitie51

Note 2 - Investment Securities - Interest Income From Investment Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Taxable	$ 51,445	$ 42,718	$ 34,472
Tax-exempt from regular federal income tax	20,651	22,194	23,616
Total interest income from investment securities	$ 72,096	$ 64,912	$ 58,088

Note 3 - Loans and Allowance 52

Note 3 - Loans and Allowance for Loan Losses (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Purchased Loans	$ 83,478	$ 121,210
Loans and Leases Receivable, Nonaccrual, Commitment to Lend	0	0
Financing Receivable, Modifications, Recorded Investment	$ 12,081	12,381	$ 15,712
Troubled Debt Restructurings During Period	1
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 58	$ 0	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0	0	0
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	$ 0	$ 0
Loans Receivable Held-for-sale, Amount	0	0
Other Real Estate	1,426	3,095
Other Real Estate, Reserve	1,905	1,816
Mortgage Loans in Process of Foreclosure, Amount	196	0
Residential Real Estate Included in OREO [Member]
Real Estate Acquired Through Foreclosure	0
Under-Market Terms, Extended Maturity Date and Court Orders [Member]
Financing Receivable, Modifications, Recorded Investment	$ 699	$ 4,731	$ 11,026
Troubled Debt Restructurings During Period	4	4	10
Under-market Modification to Payment Terms and Extended Maturity Date [Member]
Troubled Debt Restructurings During Period		3	4
Court Order [Member]
Troubled Debt Restructurings During Period		1	6
Restructured Loans [Member]
Financing Receivable, Modifications, Recorded Investment	$ 12,081	$ 12,381
Impaired Loans, Restructured, Nonaccrual Status	$ 4,285	$ 5,302

Note 3 - Loans and Allowance 53

Note 3 - Loans and Allowance for Loan Losses - Loans Receivable at Carrying Amount (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 1,287,982	$ 1,352,711
Commercial Portfolio Segment [Member]
Loans	335,996	354,697
Commercial Real Estate Portfolio Segment [Member]
Loans	568,584	542,171
Construction Portfolio Segment [Member]
Loans	5,649	2,555
Residential Portfolio Segment [Member]
Loans	65,183	87,724
Consumer Portfolio Segment [Member]
Loans	$ 312,570	$ 365,564

Note 3 - Loans and Allowance 54

Note 3 - Loans and Allowance for Loan Losses - Changes in the Accretable Yield for Purchased Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Balance at the beginning of the period	$ 1,237	$ 1,259
Reclassification from nonaccretable difference	1,852	3,912
Accretion	(2,351)	(3,934)
Balance at the end of the period	738	1,237
Change in FDIC indemnification	192	1,053
(Increase) in interest income	$ (2,159)	$ (2,881)

Note 3 - Loans and Allowance 55

Note 3 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance at beginning of period				$ 25,954				$ 29,771				$ 31,485	$ 25,954	$ 29,771	$ 31,485
(Reversal) provision			$ (1,900)			$ (3,200)							(1,900)	(3,200)	0
Chargeoffs													(5,918)	(6,772)	(5,129)
Recoveries													4,873	6,155	3,415
Net loan (losses) recoveries													(1,045)	(617)	(1,714)
Total allowance for loan losses	23,009				25,954				29,771				23,009	25,954	29,771
Unallocated Financing Receivable [Member]
Balance at beginning of period				4,835				5,963				9,058	4,835	5,963	9,058
(Reversal) provision													(1,169)	(1,128)	(3,095)
Chargeoffs													0	0	0
Recoveries													0	0	0
Net loan (losses) recoveries													0	0	0
Total allowance for loan losses	3,666				4,835				5,963				3,666	4,835	5,963
Commercial Portfolio Segment [Member]
Balance at beginning of period				8,327				9,559				5,460	8,327	9,559	5,460
(Reversal) provision													(382)	(3,237)	3,681
Chargeoffs													(961)	(2,023)	(756)
Recoveries													762	4,028	1,174
Net loan (losses) recoveries													(199)	2,005	418
Total allowance for loan losses	7,746				8,327				9,559				7,746	8,327	9,559
Commercial Real Estate Portfolio Segment [Member]
Balance at beginning of period				3,330				4,212				4,245	3,330	4,212	4,245
(Reversal) provision													431	(1,436)	126
Chargeoffs													0	0	(449)
Recoveries													88	554	290
Net loan (losses) recoveries													88	554	(159)
Total allowance for loan losses	3,849				3,330				4,212				3,849	3,330	4,212
Construction Portfolio Segment [Member]
Balance at beginning of period				152				235				654	152	235	654
(Reversal) provision													(1,716)	(83)	(33)
Chargeoffs													0	0	(431)
Recoveries													1,899	0	45
Net loan (losses) recoveries													1,899	0	(386)
Total allowance for loan losses	335				152				235				335	152	235
Residential Portfolio Segment [Member]
Balance at beginning of period				1,330				1,801				2,241	1,330	1,801	2,241
(Reversal) provision													(335)	(471)	(440)
Chargeoffs													0	0	0
Recoveries													0	0	0
Net loan (losses) recoveries													0	0	0
Total allowance for loan losses	995				1,330				1,801				995	1,330	1,801
Consumer Portfolio Segment [Member]
Balance at beginning of period				$ 7,980				$ 8,001				$ 9,827	7,980	8,001	9,827
(Reversal) provision													1,271	3,155	(239)
Chargeoffs													(4,957)	(4,749)	(3,493)
Recoveries													2,124	1,573	1,906
Net loan (losses) recoveries													(2,833)	(3,176)	(1,587)
Total allowance for loan losses	$ 6,418				$ 7,980				$ 8,001				$ 6,418	$ 7,980	$ 8,001

Note 3 - Loans and Allowance 56

Note 3 - Loans and Allowance for Loan Losses - Recorded Investment in Loans Evaluated for Impairment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Individually evaluated for impairment	$ 4,985	$ 5,048
Collectively evaluated for impairment	18,024	20,906
Total allowance for loan losses	23,009	25,954	$ 29,771	$ 31,485
Individually evaluated for impairment	25,117	24,715
Collectively evaluated for impairment	1,262,090	1,327,131
Total loans	1,287,982	1,352,711
Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	775	865
Unallocated Financing Receivable [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	3,666	4,835
Total allowance for loan losses	3,666	4,835	5,963	9,058
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	0	0
Total loans	0	0
Unallocated Financing Receivable [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	0	0
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	4,814	5,048
Collectively evaluated for impairment	2,932	3,279
Total allowance for loan losses	7,746	8,327	9,559	5,460
Individually evaluated for impairment	10,675	11,174
Collectively evaluated for impairment	325,291	343,494
Total loans	335,996	354,697
Commercial Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	30	29
Commercial Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	171	0
Collectively evaluated for impairment	3,678	3,330
Total allowance for loan losses	3,849	3,330	4,212	4,245
Individually evaluated for impairment	14,234	12,706
Collectively evaluated for impairment	553,769	528,957
Total loans	568,584	542,171
Commercial Real Estate Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	581	508
Construction Portfolio Segment [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	335	152
Total allowance for loan losses	335	152	235	654
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	5,649	2,555
Total loans	5,649	2,555
Construction Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	0	0
Residential Portfolio Segment [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	995	1,330
Total allowance for loan losses	995	1,330	1,801	2,241
Individually evaluated for impairment	208	835
Collectively evaluated for impairment	64,975	86,889
Total loans	65,183	87,724
Residential Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	0	0
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	6,418	7,980
Total allowance for loan losses	6,418	7,980	$ 8,001	$ 9,827
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	312,406	365,236
Total loans	312,570	365,564
Consumer Portfolio Segment [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Total allowance for loan losses	0	0
Total loans	$ 164	$ 328

Note 3 - Loans and Allowance 57

Note 3 - Loans and Allowance for Loan Losses - Credit Risk Profile by Internally Assigned Grade (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 1,287,982	$ 1,352,711
Pass [Member]
Loans	1,251,369	1,305,554
Substandard [Member]
Loans	35,842	45,371
Doubtful [Member]
Loans	1	1,306
Unlikely to be Collected Financing Receivable [Member]
Loans	770	480
Commercial Portfolio Segment [Member]
Loans	335,996	354,697
Commercial Portfolio Segment [Member] | Pass [Member]
Loans	324,185	340,973
Commercial Portfolio Segment [Member] | Substandard [Member]
Loans	11,811	13,724
Commercial Portfolio Segment [Member] | Doubtful [Member]
Loans	0	0
Commercial Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans	0	0
Commercial Real Estate Portfolio Segment [Member]
Loans	568,584	542,171
Commercial Real Estate Portfolio Segment [Member] | Pass [Member]
Loans	548,853	515,045
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Loans	19,731	25,830
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Loans	0	1,296
Commercial Real Estate Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans	0	0
Construction Portfolio Segment [Member]
Loans	5,649	2,555
Construction Portfolio Segment [Member] | Pass [Member]
Loans	5,649	2,555
Construction Portfolio Segment [Member] | Substandard [Member]
Loans	0	0
Construction Portfolio Segment [Member] | Doubtful [Member]
Loans	0	0
Construction Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans	0	0
Residential Portfolio Segment [Member]
Loans	65,183	87,724
Residential Portfolio Segment [Member] | Pass [Member]
Loans	62,253	84,384
Residential Portfolio Segment [Member] | Substandard [Member]
Loans	2,930	3,340
Residential Portfolio Segment [Member] | Doubtful [Member]
Loans	0	0
Residential Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans	0	0
Consumer Portfolio Segment [Member]
Loans	312,570	365,564
Consumer Portfolio Segment [Member] | Pass [Member]
Loans	310,429	362,597
Consumer Portfolio Segment [Member] | Substandard [Member]
Loans	1,370	2,477
Consumer Portfolio Segment [Member] | Doubtful [Member]
Loans	1	10
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member]
Loans	$ 770	$ 480

Note 3 - Loans and Allowance 58

Note 3 - Loans and Allowance for Loan Losses - Loans by Delinquency and Nonaccrual Status (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current and accruing	$ 1,275,068	$ 1,335,850
Nonaccrual	5,926	8,385
Total loans	1,287,982	1,352,711
Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	5,091	6,468
Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	1,366	1,511
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	531	497
Commercial Portfolio Segment [Member]
Current and accruing	334,908	353,497
Nonaccrual	297	194
Total loans	335,996	354,697
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	627	966
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	164	40
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	0	0
Commercial Real Estate Portfolio Segment [Member]
Current and accruing	561,883	533,377
Nonaccrual	5,433	6,889
Total loans	568,584	542,171
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	1,143	1,460
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	125	445
Commercial Real Estate Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	0	0
Construction Portfolio Segment [Member]
Current and accruing	5,649	2,329
Nonaccrual	0	0
Total loans	5,649	2,555
Construction Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	0	226
Construction Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	0	0
Construction Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	0	0
Residential Portfolio Segment [Member]
Current and accruing	65,183	86,098
Nonaccrual	0	1,061
Total loans	65,183	87,724
Residential Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	0	528
Residential Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	0	37
Residential Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	0	0
Consumer Portfolio Segment [Member]
Current and accruing	307,445	360,549
Nonaccrual	196	241
Total loans	312,570	365,564
Consumer Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Past due and accruing	3,321	3,288
Consumer Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Past due and accruing	1,077	989
Consumer Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Past due and accruing	$ 531	$ 497

Note 3 - Loans and Allowance 59

Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Impaired loans with no related allowance recorded, recorded investment	$ 14,949	$ 16,315
Impaired loans with no related allowance recorded, unpaid principal balance	16,961	18,897
Impaired loans with an allowance recorded, recorded investment	11,554	10,163
Impaired loans with an allowance recorded, unpaid principal balance	11,556	10,172
Impaired loans with an allowance recorded, related allowance	4,985	5,048
Total impaired loans, recorded investment	26,503	26,478
Total impaired loans, unpaid principal balance	28,517	29,069
Commercial Portfolio Segment [Member]
Impaired loans with no related allowance recorded, recorded investment	1,212	1,234
Impaired loans with no related allowance recorded, unpaid principal balance	1,271	1,303
Impaired loans with an allowance recorded, recorded investment	9,764	10,163
Impaired loans with an allowance recorded, unpaid principal balance	9,764	10,172
Impaired loans with an allowance recorded, related allowance	4,814	5,048
Commercial Real Estate Portfolio Segment [Member]
Impaired loans with no related allowance recorded, recorded investment	13,169	13,233
Impaired loans with no related allowance recorded, unpaid principal balance	14,985	15,610
Impaired loans with an allowance recorded, recorded investment	1,790	0
Impaired loans with an allowance recorded, unpaid principal balance	1,792	0
Impaired loans with an allowance recorded, related allowance	171	0
Residential Portfolio Segment [Member]
Impaired loans with no related allowance recorded, recorded investment	208	1,279
Impaired loans with no related allowance recorded, unpaid principal balance	239	1,309
Consumer Portfolio Segment [Member]
Impaired loans with no related allowance recorded, recorded investment	360	569
Impaired loans with no related allowance recorded, unpaid principal balance	$ 466	$ 675

Note 3 - Loans and Allowance 60

Note 3 - Loans and Allowance for Loan Losses - Impaired Loans, Supplemental Schedule (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Average Recorded Investment	$ 26,800	$ 30,945	$ 34,583
Recognized Interest Income	1,429	1,281	1,314
Commercial Portfolio Segment [Member]
Average Recorded Investment	11,156	12,923	12,631
Recognized Interest Income	508	512	584
Commercial Real Estate Portfolio Segment [Member]
Average Recorded Investment	14,806	16,701	20,307
Recognized Interest Income	884	725	674
Construction Portfolio Segment [Member]
Average Recorded Investment	0	102	263
Recognized Interest Income	0	0	0
Residential Portfolio Segment [Member]
Average Recorded Investment	423	746	643
Recognized Interest Income	17	19	31
Consumer Portfolio Segment [Member]
Average Recorded Investment	415	473	739
Recognized Interest Income	$ 20	$ 25	$ 25

Note 3 - Loans and Allowance 61

Note 3 - Loans and Allowance for Loan Losses - Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Number of Contracts	18	18	17
Pre-Modification Carrying Value	$ 14,162	$ 14,217	$ 16,307
Financing Receivable, Modifications, Recorded Investment	12,081	12,381	15,712
Period-End Individual Impairment Allowance	$ 43	$ 113	$ 194
Commercial Portfolio Segment [Member]
Number of Contracts	7	7	6
Pre-Modification Carrying Value	$ 2,393	$ 2,719	$ 3,138
Financing Receivable, Modifications, Recorded Investment	1,085	1,489	2,802
Period-End Individual Impairment Allowance	$ 43	$ 113	$ 194
Commercial Real Estate Portfolio Segment [Member]
Number of Contracts	10	10	10
Pre-Modification Carrying Value	$ 11,528	$ 11,257	$ 12,927
Financing Receivable, Modifications, Recorded Investment	10,788	10,673	12,684
Period-End Individual Impairment Allowance	$ 0	$ 0	$ 0
Residential Portfolio Segment [Member]
Number of Contracts	1	1	1
Pre-Modification Carrying Value	$ 241	$ 241	$ 242
Financing Receivable, Modifications, Recorded Investment	208	219	226
Period-End Individual Impairment Allowance	$ 0	$ 0	$ 0

Note 4 - Concentration of Cre62

Note 4 - Concentration of Credit Risk (Details Textual) $ in Thousands	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Unsecured Loan Limit, Percentage of Shareholders' Equity, California Financial Code	15.00%
Secured and Unsecured Loan Limit Percentage, California Financial Code	25.00%
Concentration Risk, Issuer Relationships	70
Loan Commitments and Standby Letters of Credit Related to Real Estate Loans	$ 53,874	$ 57,721
Concentration Risk, Aggregate Securities Amount	$ 5,000
Commercial Real Estate Loans [Member]
Loan To Value Ratio Requirement	75.00%
Residential Real Estate Loans [Member]
Loan To Value Ratio Requirement	80.00%
Aggregate Loans [Member] | Customer Concentration Risk [Member]
Concentration Risk, Issuer Relationships	40
Concentration Risk, Aggregate Loans Amount	$ 5,000

Note 5 - Premises, Equipment 63

Note 5 - Premises, Equipment and Other Assets (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Depreciation, Depletion and Amortization, Nonproduction	$ 3,925	$ 3,959	$ 3,523
FRB Membership, Stock Subscription, Percent of Paid-Up Capital Stock and Surplus Requirement	6.00%
LIHTC Investments	$ 10,119	12,591
Qualified Affordable Housing Project Investments, Commitment	2,299	2,299
Affordable Housing Project Investment, Write-down, Amount	625
Contingent Commitment, Year 3 [Member]
Qualified Affordable Housing Project Investments, Commitment	722
Contingent Commitment, Year 6 [Member]
Qualified Affordable Housing Project Investments, Commitment	131
Contingent Commitment, Year 7 [Member]
Qualified Affordable Housing Project Investments, Commitment	90
Contingent Commitment, Year 8 or Thereafter [Member]
Qualified Affordable Housing Project Investments, Commitment	$ 1,356

Note 5 - Premises, Equipment 64

Note 5 - Premises, Equipment and Other Assets - Premises and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Cost	$ 81,538	$ 80,684
Accumulated Depreciation and Amortization	(46,237)	(44,118)
Premises and equipment, net	35,301	36,566
Land [Member]
Cost	11,796	11,896
Accumulated Depreciation and Amortization
Premises and equipment, net	11,796	11,896
Building and Building Improvements [Member]
Cost	41,641	40,992
Accumulated Depreciation and Amortization	(26,249)	(25,180)
Premises and equipment, net	15,392	15,812
Leasehold Improvements [Member]
Cost	5,817	5,922
Accumulated Depreciation and Amortization	(4,790)	(4,599)
Premises and equipment, net	1,027	1,323
Furniture and Fixtures [Member]
Cost	22,284	21,874
Accumulated Depreciation and Amortization	(15,198)	(14,339)
Premises and equipment, net	$ 7,086	$ 7,535

Note 5 - Premises, Equipment 65

Note 5 - Premises, Equipment and Other Assets - Other Assets (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Federal Reserve Bank stock (1)	[1]	$ 14,069	$ 14,069
Other investments		158	201
Total cost method equity investments		14,227	14,270
Life insurance cash surrender value		54,101	51,535
Net deferred tax asset		33,112	55,417
Limited partnership investments		10,119	12,591
Interest receivable		23,557	21,489
Prepaid assets		4,906	4,825
Other assets		18,428	11,597
Total other assets		$ 158,450	$ 171,724
[1]	A bank applying for membership in the Federal Reserve System is required to subscribe to stock in the Federal Reserve Bank (FRB) in its district in a sum equal to six percent of the bank's paid-up capital stock and surplus. One-half of the amount of the bank's subscription shall be paid to the FRB and the remaining half will be subject to call when deemed necessary by the Board of Governors of the Federal Reserve System.

Note 5 - Premises, Equipment 66

Note 5 - Premises, Equipment and Other Assets - Amounts Recognized in Net Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investment loss included in pre-tax income	$ 1,800	$ 2,475	$ 2,850
Valuation impairment included in pre-tax income	625
Tax credits recognized in provision for income taxes	$ 1,850	$ 2,286	$ 2,650

Note 6 - Goodwill and Identif67

Note 6 - Goodwill and Identifiable Intangible Assets (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Asset Impairment	$ 0	$ 0	$ 0
Amortization Expense, Adjustment Resulting from a Change in Estimates of Useful Lives or Residual Values	$ 0	$ 0	$ 0

Note 6 - Goodwill and Identif68

Note 6 - Goodwill and Identifiable Intangible Assets - Carrying Values of Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Goodwill	$ 121,673	$ 121,673

Note 6 - Goodwill and Identif69

Note 6 - Goodwill and Identifiable Intangible Assets - Gross Carrying Amount of Intangible Assets and Accumulated Amortization (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Gross Carrying Amount	$ 67,108	$ 67,108
Accumulated Amortization	(63,258)	(60,181)
Core Deposits [Member]
Gross Carrying Amount	56,808	56,808
Accumulated Amortization	(52,987)	(50,074)
Mechant Draft Processing [Member]
Gross Carrying Amount	10,300	10,300
Accumulated Amortization	$ (10,271)	$ (10,107)

Note 6 - Goodwill and Identif70

Note 6 - Goodwill and Identifiable Intangible Assets - Estimated Future Amortization Expense for Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Amortization of identifiable intangibles	$ 3,077	$ 3,504	$ 3,856
Estimate for the Year Ended December 31, 2018	1,921
2,019	538
2,020	287
2,021	269
2,022	252
Core Deposits [Member]
Amortization of identifiable intangibles	2,913
Estimate for the Year Ended December 31, 2018	1,892
2,019	538
2,020	287
2,021	269
2,022	252
Mechant Draft Processing [Member]
Amortization of identifiable intangibles	164
Estimate for the Year Ended December 31, 2018	29
2,019
2,020
2,021
2,022

Note 7 - Deposits and Borrowe71

Note 7 - Deposits and Borrowed Funds (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Demand Deposit Overdrafts	$ 2,786	$ 2,679
Interest Expense, Time Deposits, $100,000 or More	$ 415	$ 509	$ 687

Note 7 - Deposits and Borrowe72

Note 7 - Deposits and Borrowed Funds - Deposits Detail (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Noninterest-bearing deposits	$ 2,197,526	$ 2,089,443
Transaction	904,245	865,701
Savings	1,494,024	1,493,427
Time deposits less than $100 thousand	117,848	133,712
Time deposits $100 thousand through $250 thousand	76,578	84,925
Time deposits more than $250 thousand	37,392	37,533
Total deposits	$ 4,827,613	$ 4,704,741

Note 7 - Deposits and Borrowe73

Note 7 - Deposits and Borrowed Funds - Short-term Borrowed Funds (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Collateral Carrying Value	$ 237,537	$ 227,862
Short-term borrowed funds	58,471	59,078
US Government-sponsored Enterprises Debt Securities [Member]
Collateral Carrying Value	74,173	74,031
Agency Residential MBS [Member]
Collateral Carrying Value	58,251	63,277
Corporate Debt Securities [Member]
Collateral Carrying Value	$ 105,113	$ 90,554

Note 7 - Deposits and Borrowe74

Note 7 - Deposits and Borrowed Funds - Borrowed Funds, Highest Month End Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Securities Sold under Agreements to Repurchase [Member]
Securities sold under repurchase agreements	$ 82,126	$ 74,815

Note 8 - Shareholders' Equity75

Note 8 - Shareholders' Equity (Details Textual) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)$ / sharesshares	Feb. 13, 2009$ / sharesshares
Share Price | $ / shares	$ 59.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	266,000	325,000	343,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares	$ 8.27	$ 5.97	$ 5.46
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options | $	$ 2,012
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $	4,642	$ 3,242	$ 504
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value | $	$ 1,493	1,269	1,321
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	509,000
Excess Tax Deduction Exceeding Related Share-based Compensation, Operating Activities | $	$ 1,667
Income Tax Expense (Benefit) | $	$ 37,147	21,104	17,919
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense | $		$ 394	1,284
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	14,000	18,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				246,640
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares				$ 50.92
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased	1,750,000
Additional Classes of Stock Authorized	2
Additional Classes of Stock Authorized, Shares Authorized, Per Class	1,000,000
Common Stock, Shares Authorized	150,000,000	150,000,000
Common Stock, Shares, Outstanding	26,425,000	25,907,000
Preferred Stock, Shares Outstanding	0
Common Class B [Member]
Common Stock, Shares, Outstanding	0
Accounting Standards Update 2016-09 [Member]
Income Tax Expense (Benefit) | $	$ (698)
NQSO [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Restricted Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $	$ 708	$ 753	741
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 73 days	1 year 36 days
Allocated Share-based Compensation Expense | $	$ 827	$ 1,228	$ 535
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	930,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	328 days
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0

Note 8 - Shareholders' Equity -

Note 8 - Shareholders' Equity - Information About Stock Options Granted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Options outstanding, range of exercise price, lower range (in dollars per share)	$ 40
Options outstanding, range of exercise price, upper range (in dollars per share)	$ 60
Options outstanding, number outstanding (in shares)	1,030	1,273
Options outstanding, aggregate intrinsic value	$ 10,416
Options outstanding, weighted average remaining contractual life (Year)	6 years
Options outstanding, weighted average exercise price (in dollars per share)	$ 49
Options exercisable, number outstanding (in shares)	469
Options exercisable, aggregate intrinsic value	$ 4,738
Options exercisable, weighted average remaining contractual life (Year)	3 years 36 days
Options exercisable, weighted average exercise price (in dollars per share)	$ 49
Range 1 [Member]
Options outstanding, range of exercise price, lower range (in dollars per share)	40
Options outstanding, range of exercise price, upper range (in dollars per share)	$ 45
Options outstanding, number outstanding (in shares)	400
Options outstanding, aggregate intrinsic value	$ 6,798
Options outstanding, weighted average remaining contractual life (Year)	7 years 182 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 43
Options exercisable, number outstanding (in shares)	105
Options exercisable, aggregate intrinsic value	$ 1,751
Options exercisable, weighted average remaining contractual life (Year)	6 years 328 days
Options exercisable, weighted average exercise price (in dollars per share)	$ 43
Range 2 [Member]
Options outstanding, range of exercise price, lower range (in dollars per share)	45
Options outstanding, range of exercise price, upper range (in dollars per share)	$ 50
Options outstanding, number outstanding (in shares)	22
Options outstanding, aggregate intrinsic value	$ 305
Options outstanding, weighted average remaining contractual life (Year)	4 years 36 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 46
Options exercisable, number outstanding (in shares)	22
Options exercisable, aggregate intrinsic value	$ 305
Options exercisable, weighted average remaining contractual life (Year)	4 years 36 days
Options exercisable, weighted average exercise price (in dollars per share)	$ 46
Range 3 [Member]
Options outstanding, range of exercise price, lower range (in dollars per share)	50
Options outstanding, range of exercise price, upper range (in dollars per share)	$ 55
Options outstanding, number outstanding (in shares)	310
Options outstanding, aggregate intrinsic value	$ 2,588
Options outstanding, weighted average remaining contractual life (Year)	1 year 328 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 51
Options exercisable, number outstanding (in shares)	310
Options exercisable, aggregate intrinsic value	$ 2,588
Options exercisable, weighted average remaining contractual life (Year)	1 year 328 days
Options exercisable, weighted average exercise price (in dollars per share)	$ 51
Range 4 [Member]
Options outstanding, range of exercise price, lower range (in dollars per share)	55
Options outstanding, range of exercise price, upper range (in dollars per share)	$ 60
Options outstanding, number outstanding (in shares)	298
Options outstanding, aggregate intrinsic value	$ 725
Options outstanding, weighted average remaining contractual life (Year)	8 years 109 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 57
Options exercisable, number outstanding (in shares)	32
Options exercisable, aggregate intrinsic value	$ 94
Options exercisable, weighted average remaining contractual life (Year)	2 years 36 days
Options exercisable, weighted average exercise price (in dollars per share)	$ 57

Note 8 - Shareholders' Equity77

Note 8 - Shareholders' Equity - Weighted Average Assumptions Used in the Option Pricing to Value Stock Options Granted (Details) - $ / shares		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Expected volatility (1)	[1]	20.00%	22.00%	20.00%
Expected life in years (2) (Year)	[2]	4 years 292 days	4 years 292 days	4 years 328 days
Risk-free interest rate (3)		1.97%	1.41%	1.36%
Expected dividend yield	[3]	3.28%	4.49%	3.64%
Fair value per award (in dollars per share)		$ 8.27	$ 5.97	$ 5.46
[1]	Measured using daily price changes of Company's stock over respective expected term of the option and the implied volatility derived from the market prices of the Company's stock and traded options.
[2]	The number of years that the Company estimates that the options will be outstanding prior to exercise.
[3]	The risk-free rate over the expected life based on the US Treasury yield curve in effect at the time of the grant.

Note 8 - Shareholders' Equity78

Note 8 - Shareholders' Equity - Summary of Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Outstanding at January 1, 2017 (in shares)	1,273,000
Outstanding at January 1, 2017 (in dollars per share)	$ 47.36
Granted (in shares)	266,000	325,000	343,000
Granted (in dollars per share)	$ 57.18
Exercised (in shares)	(509,000)
Exercised (in dollars per share)	$ 48.29
Forfeited or expired (in shares)
Outstanding at December 31, 2017 (in shares)	1,030,000	1,273,000
Outstanding at December 31, 2017 (in dollars per share)	$ 49.44	$ 47.36
Outstanding at December 31, 2017 (Year)	6 years
Exercisable at December 31, 2017 (in shares)	469,000
Exercisable at December 31, 2017 (in dollars per share)	$ 49.45
Exercisable at December 31, 2017 (Year)	3 years 36 days

Note 8 - Shareholders' Equity79

Note 8 - Shareholders' Equity - Summary of Nonvested Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Nonvested at January 1, 2017 (in shares)	553,000
Nonvested at January 1, 2017 (in dollars per share)	$ 5.80
Granted (in shares)	266,000	325,000	343,000
Granted (in dollars per share)	$ 8.27
Vested (in shares)	(258,000)
Vested (in dollars per share)	$ 5.78
Forfeited (in shares)
Nonvested at December 31, 2017 (in shares)	561,000	553,000
Nonvested at December 31, 2017 (in dollars per share)	$ 6.98

Note 8 - Shareholders' Equity80

Note 8 - Shareholders' Equity - Summary of the Status of Restricted Performance Shares (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Outstanding at January 1, (in shares)	48	45
Granted (in shares)	14	18
Issued upon vesting (in shares)	(13)	(15)
Forfeited (in shares)
Outstanding at December 31, (in shares)	49	48

Note 9 - Regulatory Capital (De

Note 9 - Regulatory Capital (Details Textual)	Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Capital Conservation Buffer		1.25%	0.625%	0.00%
Scenario, Forecast [Member]
Capital Conservation Buffer	2.50%

Note 9 - Regulatory Capital - C

Note 9 - Regulatory Capital - Capital Ratios for the Company and the Bank (Details) - USD ($) $ in Thousands		Dec. 31, 2017		Dec. 31, 2016
Common Equity Tier 1 Capital		$ 479,259		$ 443,574
Common Equity Tier 1 Capital, ratio		15.36%		14.85%
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 179,377		$ 153,126
Common Equity Tier 1 Capital Required for Capital Adequacy, ratio		5.75%	[1]	5.125%	[2]
Common Equity Tier 1 Capital To Be Well-capitalized
Common Equity Tier 1 Capital To Be Well-capitalized, ratio
Tier 1 Capital		$ 479,259		$ 443,574
Tier 1 Capital, raio		15.36%		14.85%
Tier 1 Capital Required for Capital Adequacy		$ 226,170		$ 197,944
Tier 1 Capital Required for Capital Adequacy, ratio		7.25%	[1]	6.625%	[2]
Tier 1 Capital To Be Well-capitalized
Tier 1 Capital To Be Well-capitalized, ratio
Total Capital		$ 504,576		$ 476,595
Total Capital, ratio		16.17%		15.95%
Total Capital Required for Capital Adequacy		$ 288,562		$ 257,700
Total Capital Required for Capital Adequacy, ratio		9.25%	[1]	8.625%	[2]
Total Capital To Be Well-capitalized
Total Capital To Be Well-capitalized, ratio
Leverage Ratio, amount	[3]	$ 479,259		$ 443,574
Leverage Ratio	[3]	8.86%		8.46%
Leverage Ratio Required for Capital Adequacy, amount	[3]	$ 216,280		$ 209,702
Leverage Ratio Required for Capital Adequacy	[3]	4.00%		4.00%
Leverage Ratio To Be Well-capitalized, amount	[3]
Leverage Ratio To Be Well-capitalized	[3]
Westamerica Bank [Member]
Common Equity Tier 1 Capital		$ 383,796		$ 344,739
Common Equity Tier 1 Capital, ratio		12.50%		11.70%
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 176,568		$ 150,982
Common Equity Tier 1 Capital Required for Capital Adequacy, ratio		5.75%	[1]	5.125%	[2]
Common Equity Tier 1 Capital To Be Well-capitalized		$ 199,599		$ 191,489
Common Equity Tier 1 Capital To Be Well-capitalized, ratio		6.50%		6.50%
Tier 1 Capital		$ 383,796		$ 344,739
Tier 1 Capital, raio		12.50%		11.70%
Tier 1 Capital Required for Capital Adequacy		$ 222,630		$ 195,172
Tier 1 Capital Required for Capital Adequacy, ratio		7.25%	[1]	6.625%	[2]
Tier 1 Capital To Be Well-capitalized		$ 245,660		$ 235,680
Tier 1 Capital To Be Well-capitalized, ratio		8.00%		8.00%
Total Capital		$ 415,113		$ 383,572
Total Capital, ratio		13.52%		13.02%
Total Capital Required for Capital Adequacy		$ 284,045		$ 254,092
Total Capital Required for Capital Adequacy, ratio		9.25%	[1]	8.625%	[2]
Total Capital To Be Well-capitalized		$ 307,076		$ 294,600
Total Capital To Be Well-capitalized, ratio		10.00%		10.00%
Leverage Ratio, amount	[3]	$ 383,796		$ 344,739
Leverage Ratio	[3]	7.16%		6.63%
Leverage Ratio Required for Capital Adequacy, amount	[3]	$ 214,468		$ 208,005
Leverage Ratio Required for Capital Adequacy	[3]	4.00%		4.00%
Leverage Ratio To Be Well-capitalized, amount	[3]	$ 268,085		$ 260,006
Leverage Ratio To Be Well-capitalized	[3]	5.00%		5.00%
[1]	Includes 1.25% capital conservation buffer.
[2]	Includes 0.625% capital conservation buffer.
[3]	The leverage ratio consists of Tier 1capital divided by the most recent quarterly average total assets, excluding certain intangible assets.

Note 10 - Income Taxes (Details

Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 12,300
Operating Loss Carryforwards	0
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax	1,752
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	13	$ 57
Tax Credit Carryforward, Amount	$ 0
Internal Revenue Service (IRS) [Member] | Tax Year 2015 [Member]
Open Tax Year	2,015
Internal Revenue Service (IRS) [Member] | Tax Year 2014 [Member]
Open Tax Year	2,014
Internal Revenue Service (IRS) [Member] | Tax Year 2016 [Member]
Open Tax Year	2,016
California Franchise Tax Board [Member] | Tax Year 2015 [Member]
Open Tax Year	2,015
California Franchise Tax Board [Member] | Tax Year 2014 [Member]
Open Tax Year	2,014
California Franchise Tax Board [Member] | Tax Year 2016 [Member]
Open Tax Year	2,016
California Franchise Tax Board [Member] | Tax Year 2013 [Member]
Open Tax Year	2,013
California Franchise Tax Board [Member] | Tax Year 2012 [Member]
Open Tax Year	2,012
California Franchise Tax Board [Member] | Tax Year 2011 [Member]
Open Tax Year	2,011

Note 10 - Income Taxes - Compon

Note 10 - Income Taxes - Components of Net Deferred Tax Asset (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Deferred tax asset
Allowance for credit losses	$ 7,349	$ 11,801
State franchise taxes	1,871	2,679
AMT carryforward	1,752
Securities available for sale	8,586	7,283
Deferred compensation	5,279	8,043
Real estate owned	553	756
Purchased assets and assumed liabilities	1,111	3,026
Post-retirement benefits	526	903
Employee benefit accruals	2,066	3,399
VISA Class B shares	96	137
Limited partnership investments	57	86
Impaired capital assets	3,056	18,465
Accrued liabilities	1,609	967
Premises and equipment	299	577
Other	520	724
Total deferred tax asset	34,730	58,846
Deferred tax liability
Net deferred loan fees	281	346
Intangible assets	1,247	2,955
Other	90	128
Total deferred tax liability	1,618	3,429
Net deferred tax asset	$ 33,112	$ 55,417

Note 10 - Income Taxes - Provis

Note 10 - Income Taxes - Provision for Federal and State Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal	$ 1,778	$ 16,258	$ 9,647
State	7,810	7,292	6,738
Total current	9,588	23,550	16,385
Federal	14,461	(2,604)	1,643
State	783	158	(109)
Total deferred	15,244	(2,446)	1,534
Federal	12,315
Provision for income taxes	37,147	21,104	17,919
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Federal	12,315
State and Local Jurisdiction [Member]
Federal

Note 10 - Income Taxes - Reconc

Note 10 - Income Taxes - Reconciliation of Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Federal income taxes due at statutory rate	$ 30,509	$ 27,985	$ 26,835
Interest on state and municipal securities and loans not taxable for federal income tax purposes	(7,794)	(8,382)	(9,046)
State franchise taxes, net of federal income tax benefit	5,586	4,843	4,309
Re-measurement of net deferred tax asset due to enactment of new federal tax rate	12,315
Stock compensation deduction in excess of book expense	(583)
Tax credits	(1,850)	(2,286)	(2,600)
Dividend received deduction	(60)	(52)	(45)
Cash value life insurance	(603)	(607)	(599)
Other	(373)	(397)	(935)
Provision for income taxes	$ 37,147	$ 21,104	$ 17,919

Note 10 - Income Taxes - Reco87

Note 10 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Balance	$ 1,099	$ 1,243
Additions for tax positions taken in the current period
Reductions for tax positions taken in the current period
Additions for tax positions taken in prior years
Reductions for tax positions taken in prior years		(144)
Decrease related to settlements with taxing authorities	(190)
Decrease as a result of a lapse in statute of limitations
Balance	$ 909	$ 1,099

Note 11 - Fair Value Measurem88

Note 11 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Securities Selected for OTTI Analysis, Market Price, Threshold	95.00%
Loans and Leases Receivable, Allowance	$ 23,009	$ 25,954
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Appraisal Rate	10.00%

Note 11 - Fair Value Measurem89

Note 11 - Fair Value Measurements - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Investment securities available for sale		$ 2,193,507	$ 1,890,758
Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		2,193,507	1,890,758
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale			673
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		2,193,507	1,890,085
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
US Government-sponsored Enterprises Debt Securities [Member]
Investment securities available for sale		119,319	138,660
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		119,319	138,660
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		119,319	138,660
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Agency Residential MBS [Member]
Investment securities available for sale		767,706	691,499
Agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		767,706	691,499
Agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
Agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		767,706	691,499
Agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Non-agency Residential MBS [Member]
Investment securities available for sale		154	271
Non-agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		154	271
Non-agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
Non-agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		154	271
Non-agency Residential MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Agency Commercial MBS [Member]
Investment securities available for sale		2,219
Agency Commercial MBS [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		2,219
Agency Commercial MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
Agency Commercial MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		2,219
Agency Commercial MBS [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
US Government Agencies Debt Securities [Member]
Investment securities available for sale		1,590	2,025
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		1,590	2,025
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		1,590	2,025
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
US States and Political Subdivisions Debt Securities [Member]
Investment securities available for sale		185,221	183,411
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		185,221	183,411
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		185,221	183,411
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Asset-backed Securities [Member]
Investment securities available for sale			695
Asset-backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale			695
Asset-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
Asset-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale			695
Asset-backed Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Domestic Corporate Debt Securities [Member]
Investment securities available for sale		1,115,498	860,857
Domestic Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		1,115,498	860,857
Domestic Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale
Domestic Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		1,115,498	860,857
Domestic Corporate Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
FHLMC and FNMA Stock [Member]
Investment securities available for sale	[1],[2]		10,869
FHLMC and FNMA Stock [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale			10,869
FHLMC and FNMA Stock [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale			17
FHLMC and FNMA Stock [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale			10,852
FHLMC and FNMA Stock [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
Other Securities [Member]
Investment securities available for sale		1,800	2,471
Other Securities [Member] | Fair Value, Measurements, Recurring [Member]
Investment securities available for sale		1,800	2,471
Other Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Investment securities available for sale			656
Other Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Investment securities available for sale		1,800	1,815
Other Securities [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Investment securities available for sale
[1]	Federal Home Loan Mortgage Corporation
[2]	Federal National Mortgage Association

Note 11 - Fair Value Measurem90

Note 11 - Fair Value Measurements - Assets Measured at Fair Value on a Nonrecurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Fair Value	$ 12,280	$ 12,620
Total Losses	(219)	(705)
Fair Value, Inputs, Level 1 [Member]
Fair Value
Fair Value, Inputs, Level 2 [Member]
Fair Value
Fair Value, Inputs, Level 3 [Member]
Fair Value	12,280	12,620
Other Real Estate Owned [Member]
Fair Value	1,426	3,095
Total Losses	(219)	(705)
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value	1,426	3,095
Impaired Loans [Member] | Commercial Portfolio Segment [Member]
Fair Value	4,950	5,115
Total Losses
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value	5,904	4,410
Total Losses
Impaired Loans [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Portfolio Segment [Member]
Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Portfolio Segment [Member]
Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Portfolio Segment [Member]
Fair Value	4,950	5,115
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial Real Estate Portfolio Segment [Member]
Fair Value	$ 5,904	$ 4,410

Note 11 - Fair Value Measurem91

Note 11 - Fair Value Measurements - Fair Value Estimates for Financial Instruments, Excluding Financial Instruments Recorded at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Investment securities held to maturity	$ 1,155,342	$ 1,340,741
Reported Value Measurement [Member]
Cash and due from banks	575,002	462,271
Investment securities held to maturity	1,158,864	1,346,312
Loans	1,264,973	1,326,757
Deposits	4,827,613	4,704,741
Short-term borrowed funds	58,471	59,078
Estimate of Fair Value Measurement [Member]
Cash and due from banks	575,002	462,271
Investment securities held to maturity	1,155,342	1,340,741
Loans	1,257,811	1,337,774
Deposits	4,824,586	4,702,797
Short-term borrowed funds	58,471	59,078
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	575,002	462,271
Investment securities held to maturity
Loans
Deposits
Short-term borrowed funds
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and due from banks
Investment securities held to maturity	1,155,342	1,340,741
Loans
Deposits	4,595,795	4,448,571
Short-term borrowed funds	58,471	59,078
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and due from banks
Investment securities held to maturity
Loans	1,257,811	1,337,774
Deposits	228,791	254,226
Short-term borrowed funds

Note 12 - Lease Commitments (De

Note 12 - Lease Commitments (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Facilities Leased	58
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals	$ 2,088
Operating Leases, Rent Expense, Minimum Rentals	6,695	$ 6,823	$ 8,359
Operating Leases, Rent Expense, Sublease Rentals	406	435	1,721
Operating Leases, Rent Expense, Net	$ 6,289	$ 6,388	$ 6,638

Note 12 - Lease Commitments - M

Note 12 - Lease Commitments - Minimum Future Rental Payments Under Noncancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2017USD ($)
2,018	$ 6,481
2,019	4,882
2,020	3,143
2,021	1,462
2,022	732
Thereafter	825
Total minimum lease payments	$ 17,525

Note 13 - Commitments and Con94

Note 13 - Commitments and Contingent Liabilities (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Unfunded Loan Commitments	$ 272,646	$ 304,508
Other Liabilities [Member]
Reserve for Unfunded Commitments	2,308	2,408
Financial Standby Letter of Credit [Member]
Letters of Credit Outstanding, Amount	19,263	21,732
Commercial Standby Letters of Credit [Member]
Letters of Credit Outstanding, Amount	0	$ 0
Customer Refunds [Member]
Loss Contingency Accrual	$ 5,542

Note 14 - Retirement Benefit 95

Note 14 - Retirement Benefit Plans (Details Textual) - USD ($) xbrli-pure in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Contribution Plan, Cost	$ 944	$ 1,000	$ 734
Employee Stock Ownership Plan (ESOP), Compensation Expense	$ 1,098	$ 1,075	$ 1,147
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	0.00%

Note 14 - Retirement Benefit 96

Note 14 - Retirement Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Service benefit	$ (311)	$ (153)	$ (202)
Interest cost	95	108	106
Amortization of unrecognized transition obligation	61	61	61
Net periodic (benefit) cost	(155)	16	(35)
Amortization of unrecognized transition obligation, net of tax	(34)	(36)	(36)
Total recognized in net periodic (benefit) cost and accumulated other comprehensive income	$ (189)	$ (20)	$ (71)

Note 14 - Retirement Benefit 97

Note 14 - Retirement Benefit Plans - Obligation and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Benefit obligation at beginning of year	$ 2,319	$ 2,522	$ 2,782
Service benefit	(311)	(153)	(202)
Interest cost	95	108	106
Benefits paid	(145)	(158)	(164)
Benefit obligation at end of year	1,958	2,319	2,522
Accumulated post-retirement benefit obligation	2,319	2,319	2,522	$ 1,958	$ 2,319	$ 2,522
Fair value of plan assets
Accumulated post-retirement benefit obligation in excess of plan assets				1,958	2,319	2,522
Retirees [Member]
Benefit obligation at beginning of year	1,705	1,695
Benefit obligation at end of year	1,575	1,705	1,695
Accumulated post-retirement benefit obligation	1,575	1,705	1,695	1,575	1,705	1,695
Fully Eligible Participants [Member]
Benefit obligation at beginning of year	606	809
Benefit obligation at end of year	382	606	809
Accumulated post-retirement benefit obligation	382	606	809	382	606	809
Other Participants [Member]
Benefit obligation at beginning of year	8	18
Benefit obligation at end of year	1	8	18
Accumulated post-retirement benefit obligation	$ 1	$ 8	$ 18	$ 1	$ 8	$ 18

Note 14 - Retirement Benefit 98

Note 14 - Retirement Benefit Plans - Assumptions (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Discount rate	3.70%	4.10%	4.30%
Discount rate	4.10%	4.30%	3.80%

Note 14 - Retirement Benefit 99

Note 14 - Retirement Benefit Plans - Estimated Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2017USD ($)
2,018	$ 138
2,019	131
2,020	124
2,021	118
2,022	112
Years 2023-2027	$ 482

Note 15 - Related Party Tran100

Note 15 - Related Party Transactions - Related Party Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Balance at January 1,	$ 867	$ 911
Originations
Principal reductions	(245)	(44)
Balance at December 31,	$ 622	$ 867
Percent of total loans outstanding.	0.05%	0.06%

Note 16 - Regulatory Matters (D

Note 16 - Regulatory Matters (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Federal Reserve Bank Average Balance Deposit	$ 458,186	$ 365,880

Note 17 - Other Comprehensiv102

Note 17 - Other Comprehensive Income - Components of Other Comprehensive Income (Loss) and Other Related Tax Effects (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net unrealized gains (losses) arising during the year, before tax	$ (3,767)	$ (18,610)	$ (8,028)
Net unrealized gains (losses) arising during the year, tax	1,585	7,825	3,375
Net unrealized gains (losses) arising during the year, net of tax	(2,182)	(10,785)	(4,653)
Reclassification of gains (losses) included in net income, before tax	(7,955)
Reclassification of gains (losses) included in net income, tax	3,345
Reclassification of gains (losses) included in net income, net of tax	(4,610)
Net unrealized losses arising during the year, before tax	(11,722)	(18,610)	(8,028)
Net unrealized gains (losses) arising during the year, tax	4,930	7,825	3,375
Changes in unrealized gains and losses on securities available for sale, net of tax	(6,792)	(10,785)	(4,653)
Post-retirement benefit obligation, before tax	59	61	61
Post-retirement benefit obligation, tax	(25)	(25)	(25)
Post-retirement benefit obligation, net of tax	34	36	36
Other comprehensive income (loss), before tax	(11,663)	(18,549)	(7,967)
Other comprehensive income (loss), tax	4,905	7,800	3,350
Other comprehensive income (loss), net of tax	$ (6,758)	$ (10,749)	$ (4,617)

Note 17 - Other Comprehensiv103

Note 17 - Other Comprehensive Income - Cumulative Other Comprehensive Income (Loss) Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance	$ 561,367	$ 532,205	$ 526,603
Net change	(6,758)	(10,749)	(4,617)
Balance	590,239	561,367	532,205
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(34)	(70)	(106)
Net change	34	36	36
Balance		(34)	(70)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Balance	(10,040)	745	5,398
Net change	(6,792)	(10,785)	(4,653)
Balance	(16,832)	(10,040)	745
AOCI Attributable to Parent [Member]
Balance	(10,074)	675	5,292
Net change	(6,758)	(10,749)	(4,617)
Balance	$ (16,832)	$ (10,074)	$ 675

Note 18 - Earnings Per Commo104

Note 18 - Earnings Per Common Share (Details Textual) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	323	773	1,313

Note 18 - Earnings Per Commo105

Note 18 - Earnings Per Common Share - Earnings Per Common Share and Diluted Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income (numerator)	$ 4,160	$ 15,017	$ 15,799	$ 15,049	$ 14,453	$ 15,628	$ 14,546	$ 14,226	$ 14,578	$ 14,857	$ 14,761	$ 14,557	$ 50,025	$ 58,853	$ 58,753
Average Common Shares Outstanding (in shares)													26,291	25,612	25,555
Basic earnings (in dollars per share)	$ 0.16	$ 0.57	$ 0.60	$ 0.58	$ 0.56	$ 0.61	$ 0.57	$ 0.56	$ 0.57	$ 0.58	$ 0.58	$ 0.57	$ 1.90	$ 2.30	$ 2.30
Add common stock equivalents for options (in shares)													128	66	22
Weighted average number of common shares outstanding - diluted (denominator) (in shares)													26,419	25,678	25,577
Diluted earnings (in dollars per share)	$ 0.16	$ 0.57	$ 0.60	$ 0.57	$ 0.56	$ 0.61	$ 0.57	$ 0.56	$ 0.57	$ 0.58	$ 0.58	$ 0.57	$ 1.89	$ 2.29	$ 2.30

Note 19 - Westamerica Bancor106

Note 19 - Westamerica Bancorporation (Parent Company Only Condensed Financial Information) - Statements of Income and Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Salaries and related benefits													$ 51,519	$ 51,507	$ 52,192
Income before taxes and equity in undistributed income of subsidiaries	$ 23,866	$ 21,106	$ 22,314	$ 19,886	$ 19,677	$ 21,655	$ 19,659	$ 18,966	$ 19,126	$ 19,534	$ 19,181	$ 18,831	87,172	79,957	76,672
Income tax benefit													(37,147)	(21,104)	(17,919)
Net income	$ 4,160	$ 15,017	$ 15,799	$ 15,049	$ 14,453	$ 15,628	$ 14,546	$ 14,226	$ 14,578	$ 14,857	$ 14,761	$ 14,557	50,025	58,853	58,753
Comprehensive income													43,267	48,104	54,136
Parent Company [Member]
Dividends from subsidiaries													12,728	56,824	68,981
Interest income													43	25	10
Other income													8,590	8,315	8,411
Total income													21,361	65,164	77,402
Interest on borrowings															1
Salaries and related benefits													7,163	7,079	6,291
Other expense													3,416	3,290	3,424
Total expense													10,579	10,369	9,716
Income before taxes and equity in undistributed income of subsidiaries													10,782	54,795	67,686
Income tax benefit													241	1,025	803
Earnings of subsidiaries greater (less) than subsidiary dividends													39,002	3,033	(9,736)
Net income													50,025	58,853	58,753
Other comprehensive loss, net of tax													(6,758)	(10,749)	(4,617)
Comprehensive income													$ 43,267	$ 48,104	$ 54,136

Note 19 - Westamerica Bancor107

Note 19 - Westamerica Bancorporation (Parent Company Only Condensed Financial Information) - Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Premises and equipment, net	$ 35,301	$ 36,566
Other assets	158,450	171,724
Total assets	5,513,046	5,366,083
Other liabilities	36,723	40,897
Total liabilities	4,922,807	4,804,716
Shareholders' equity	590,239	561,367	$ 532,205	$ 526,603
Total liabilities and shareholders' equity	5,513,046	5,366,083
Parent Company [Member]
Cash	53,409	64,054	$ 26,453	$ 7,451
Investment securities available for sale		656
Premises and equipment, net	9,639	9,165
Accounts receivable from Westamerica Bank	538	522
Other assets	40,547	34,077
Total assets	605,364	577,101
Accounts payable to Westamerica Bank	92	705
Other liabilities	15,033	15,029
Total liabilities	15,125	15,734
Shareholders' equity	590,239	561,367
Total liabilities and shareholders' equity	605,364	577,101
Parent Company [Member] | Westamerica Bank [Member]
Investment	500,776	468,172
Parent Company [Member] | Non-bank Subsidiaries [Member]
Investment	$ 455	$ 455

Note 19 - Westamerica Bancor108

Note 19 - Westamerica Bancorporation (Parent Company Only Condensed Financial Information) - Cash Flows Statement (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities:
Net income	$ 4,160	$ 15,017	$ 15,799	$ 15,049	$ 14,453	$ 15,628	$ 14,546	$ 14,226	$ 14,578	$ 14,857	$ 14,761	$ 14,557	$ 50,025	$ 58,853	$ 58,753
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization/accretion													26,082	19,939	16,402
Life insurance premiums paid													(842)	(828)	(782)
Increase in other assets													(890)	(2,493)	(1,046)
Stock option compensation expense													1,824	1,494	1,272
Provision (benefit) for deferred income tax													15,244	(2,446)	1,534
(Decrease) increase in other liabilities													(3,016)	2,026	(5,754)
Net Cash Provided by Operating Activities													80,754	77,637	70,404
Investing Activities:
Purchases of premises and equipment													(2,720)	(1,818)	(4,474)
Net Cash Provided by Investing Activities													(73,258)	(197,263)	(102,264)
Financing Activities:
Exercise of stock options/issuance of shares													24,583	24,031	4,848
Taxes paid by withholding shares for tax purposes														(356)	(357)
Retirement of common stock													(314)	(5,424)	(14,735)
Common stock dividends paid													(41,299)	(39,924)	(39,124)
Net Cash Used in Financing Activities													105,235	148,853	84,068
Net change in cash													112,731	29,227	52,208
Supplemental disclosure of cash flow activities:
Interest paid for the period													1,931	2,202	2,533
Income tax payments for the period													17,351	19,264	17,666
Parent Company [Member]
Operating Activities:
Net income													50,025	58,853	58,753
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization/accretion													319	305	326
Decrease (increase) in accounts receivable from affiliates													(16)	299	(217)
Life insurance premiums paid													(704)	(683)	(637)
Increase in other assets													(1,499)	(1,257)	(1,076)
Stock option compensation expense													1,824	1,494	1,272
Tax benefit (increase) decrease upon exercise of stock options and expiration of stock options														(394)	1,284
Provision (benefit) for deferred income tax													(3,971)	1,983	(491)
(Decrease) increase in other liabilities													202	1,392	743
Earnings of subsidiaries (greater) less than subsidiary dividends													(39,002)	(3,033)	9,736
Gain on sales of property and equipment													(793)	(79)	(39)
Net Cash Provided by Operating Activities													6,385	58,880	69,654
Investing Activities:
Purchases of premises and equipment
Net Cash Provided by Investing Activities
Financing Activities:
Exercise of stock options/issuance of shares													24,583	24,031	4,848
Taxes paid by withholding shares for tax purposes														(356)	(357)
Tax benefit increase (decrease) upon exercise of stock options and expiration of stock options														394	(1,284)
Retirement of common stock													(314)	(5,424)	(14,735)
Common stock dividends paid													(41,299)	(39,924)	(39,124)
Net Cash Used in Financing Activities													(17,030)	(21,279)	(50,652)
Net change in cash													(10,645)	37,601	19,002
Cash at Beginning of Period				$ 64,054				$ 26,453				$ 7,451	64,054	26,453	7,451
Cash at End of Period	$ 53,409				$ 64,054				$ 26,453				53,409	64,054	26,453
Supplemental disclosure of cash flow activities:
Interest paid for the period															1
Income tax payments for the period													$ 17,351	$ 19,264	$ 17,666

Note 20 - Quarterly Financia109

Note 20 - Quarterly Financial Information - Quarterly Financial Information (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest and loan fee income	$ 34,204	$ 33,145	$ 33,163	$ 33,324	$ 33,209	$ 33,468	$ 33,727	$ 33,647	$ 33,888	$ 34,299	$ 34,425	$ 33,917	$ 133,836	$ 134,051	$ 136,529
Net interest income	33,733	32,672	32,687	32,844	32,709	32,945	33,186	33,095	33,325	33,714	33,808	33,258	131,936	131,935	134,105
(Reversal of) provision for loan losses			(1,900)			(3,200)							(1,900)	(3,200)	0
Noninterest income	20,300	12,548	12,123	11,657	11,545	11,598	11,702	11,729	11,305	11,993	12,269	12,300	56,628	46,574	47,867
Noninterest expense	30,167	24,114	24,396	24,615	24,577	26,088	25,229	25,858	25,504	26,173	26,896	26,727	103,292	101,752	105,300
Income before taxes and equity in undistributed income of subsidiaries	23,866	21,106	22,314	19,886	19,677	21,655	19,659	18,966	19,126	19,534	19,181	18,831	87,172	79,957	76,672
Net income	$ 4,160	$ 15,017	$ 15,799	$ 15,049	$ 14,453	$ 15,628	$ 14,546	$ 14,226	$ 14,578	$ 14,857	$ 14,761	$ 14,557	$ 50,025	$ 58,853	$ 58,753
Basic earnings (in dollars per share)	$ 0.16	$ 0.57	$ 0.60	$ 0.58	$ 0.56	$ 0.61	$ 0.57	$ 0.56	$ 0.57	$ 0.58	$ 0.58	$ 0.57	$ 1.90	$ 2.30	$ 2.30
Diluted earnings (in dollars per share)	0.16	0.57	0.60	0.57	0.56	0.61	0.57	0.56	0.57	0.58	0.58	0.57	1.89	2.29	2.30
Dividends paid (in dollars per share)	0.40	0.39	0.39	0.39	0.39	0.39	0.39	0.39	0.39	0.38	0.38	0.38	1.57	1.56	1.53
Share price, common stock (in dollars per share)	59.55												59.55
Minimum [Member]
Share price, common stock (in dollars per share)	53.96	49.54	51.31	54.12	48.20	46.61	45.86	40.72	42.96	43	42.70	40.68	53.96	48.20	42.96
Maximum [Member]
Share price, common stock (in dollars per share)	$ 63.03	$ 59.54	$ 57.78	$ 64.07	$ 65.34	$ 50.96	$ 51.53	$ 49.63	$ 49.64	$ 51.90	$ 51.69	$ 48.44	$ 63.03	$ 65.34	$ 49.64