Washington Trust Bancorp (WASH) 10-K 25 Feb 20 2019 FY Annual report Financial data

DOCUMENT AND ENTITY INFORMATION

DOCUMENT AND ENTITY INFORMATION - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 31, 2020	Jun. 30, 2019
Cover page.
Entity Central Index Key	0000737468
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-32991
Entity Registrant Name	WASHINGTON TRUST BANCORP, INC
Entity Incorporation, State or Country Code	RI
Entity Tax Identification Number	05-0404671
Entity Address, Address Line One	23 Broad Street,
Entity Address, City or Town	Westerly,
Entity Address, State or Province	RI
Entity Address, Postal Zip Code	02891
City Area Code	401
Local Phone Number	348-1200
Title of 12(b) Security	COMMON STOCK, $.0625 PAR VALUE PER SHARE
Trading Symbol	WASH
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 777,287,665
Entity Common Stock, Shares Outstanding		17,363,456
Documents Incorporated by Reference [Text Block]	Portions of the Registrant’s Proxy Statement dated March 17, 2020 for the Annual Meeting of Shareholders to be held on April 28, 2020 are incorporated by reference into Part III of this Form 10-K.

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands		Dec. 31, 2019		Dec. 31, 2018
Assets:
Cash and due from banks		$ 132,193		$ 89,923
Short-term investments		6,262		3,552
Mortgage loans held for sale, at fair value		27,833		20,996
Securities:
Available for sale debt securities, at fair value		899,490		927,810
Held to maturity debt securities, at amortized cost (fair value $10,316 at December 31, 2018)		0		10,415
Total securities		899,490		938,225
Federal Home Loan Bank stock, at cost		50,853		46,068
Loans:
Total loans	[1]	3,892,999		3,680,360
Less allowance for loan losses		27,014		27,072
Net loans		3,865,985		3,653,288
Premises and equipment, net		28,700		29,005
Operating lease right-of-use assets		26,792		0
Investment in bank-owned life insurance		82,490		80,463
Goodwill		63,909		63,909
Identifiable intangible assets, net		7,218		8,162
Other assets		100,934		77,175
Total assets		5,292,659		5,010,766
Liabilities:
Noninterest-bearing deposits		609,924		603,216
Interest-bearing deposits		2,888,958		2,920,832
Total deposits		3,498,882		3,524,048
Federal Home Loan Bank advances		1,141,464		950,722
Junior subordinated debentures		22,681		22,681
Operating lease liabilities		28,861	[2]	0
Other liabilities		97,279		65,131
Total liabilities		4,789,167		4,562,582
Commitments and contingencies (Note 22)
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares; issued and outstanding 17,363,455 shares in 2019 and 17,302,037 in 2018		1,085		1,081
Paid-in capital		123,281		119,888
Retained earnings		390,363		355,524
Accumulated other comprehensive loss		(11,237)		(28,309)
Total shareholders’ equity		503,492		448,184
Total liabilities and shareholders’ equity		$ 5,292,659		$ 5,010,766
[1]	Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 .
[2]	Includes short-term operating lease liabilities of $2.5 million .

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Mortgage loans held for sale, fair value	$ 27,833	$ 20,996
Held to maturity securities fair value	$ 0	$ 10,316
Common stock, par value (in dollars per share)	$ 0.0625	$ 0.0625
Common stock, shares authorized (in shares)	60,000,000	60,000,000
Common stock, shares issued (in shares)	17,363,455	17,302,037
Common stock, shares outstanding (in shares)	17,363,455	17,302,037

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Interest income:
Interest and fees on loans		$ 165,519	$ 149,932	$ 126,940
Interest on mortgage loans held for sale		1,237	1,212	1,022
Taxable interest on debt securities		26,367	21,816	18,927
Nontaxable interest on debt securities		18	61	249
Dividends on Federal Home Loan Bank stock		2,855	2,369	1,774
Other interest income		1,667	1,017	674
Total interest and dividend income		197,663	176,407	149,586
Interest expense:
Deposits		37,101	24,175	15,064
Federal Home Loan Bank advances		26,168	19,073	14,377
Junior subordinated debentures		980	869	613
Other interest expense		0	0	1
Total interest expense		64,249	44,117	30,055
Net interest income	[1]	133,414	132,290	119,531
Provision for loan losses		1,575	1,550	2,600
Net interest income after provision for loan losses		131,839	130,740	116,931
Noninterest income:
Wealth management revenues	[1]	36,848	38,341	39,346
Mortgage banking revenues	[1]	14,795	10,381	11,392
Card interchange fees	[1]	4,214	3,768	3,502
Service charges on deposit accounts	[1]	3,684	3,628	3,672
Loan related derivative income	[1]	3,993	2,461	3,214
Income from bank-owned life insurance	[1]	2,354	2,196	2,161
Net realized losses on securities	[1]	(53)	0	0
Other income	[1]	1,245	1,339	1,522
Total noninterest income	[1]	67,080	62,114	64,809
Noninterest expense:
Salaries and employee benefits		72,761	69,277	68,891
Outsourced services		10,598	8,684	6,920
Net occupancy		7,821	7,891	7,521
Equipment		4,081	4,312	5,358
Legal, audit and professional fees		2,535	2,427	2,294
FDIC deposit insurance costs		618	1,612	1,647
Advertising and promotion		1,534	1,406	1,481
Amortization of intangibles		943	979	1,035
Change in fair value of contingent consideration		0	(187)	(643)
Other expenses		9,849	9,761	9,596
Total noninterest expense		110,740	106,162	104,100
Income before income taxes		88,179	86,692	77,640
Income tax expense		19,061	18,260	31,715
Net income		69,118	68,432	45,925
Net income available to common shareholders		$ 68,979	$ 68,288	$ 45,817
Weighted average common shares outstanding - basic		17,331	17,272	17,207
Weighted average common shares outstanding - diluted		17,414	17,391	17,338
Per share information:
Basic earnings per common share (in dollars per share)		$ 3.98	$ 3.95	$ 2.66
Diluted earnings per common share (in dollars per share)		$ 3.96	$ 3.93	$ 2.64
[1]	As reported in the Consolidated Statements of Income.

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 69,118	$ 68,432	$ 45,925
Other comprehensive income (loss), net of tax:
Net change in fair value of available for sale debt securities	19,988	(9,228)	621
Net change in fair value of cash flow hedges	(984)	619	(52)
Net change in defined benefit plan obligations	(1,932)	3,810	(97)
Total other comprehensive income (loss), net of tax	17,072	(4,799)	472
Total comprehensive income	$ 86,190	$ 63,633	$ 46,397

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Common stock, shares outstanding, beginning balance at Dec. 31, 2016		17,171,000
Stockholders' equity, beginning balance at Dec. 31, 2016	$ 390,804	$ 1,073	$ 115,123	$ 294,365	$ (19,757)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	45,925			45,925
Total other comprehensive income (loss), net of tax	472				472
Cash dividends declared	(26,759)			(26,759)
Share-based compensation	2,577		2,577
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered, shares		56,000
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered	265	$ 4	261
Reclassification of income tax effects due to the adoption of ASU 2018-02	0			4,225	(4,225)
Common stock, shares outstanding, ending balance at Dec. 31, 2017		17,227,000
Stockholders' equity, ending balance at Dec. 31, 2017	413,284	$ 1,077	117,961	317,756	(23,510)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	68,432			68,432
Total other comprehensive income (loss), net of tax	(4,799)				(4,799)
Cash dividends declared	(30,664)			(30,664)
Share-based compensation	2,602		2,602
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered, shares		75,000
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered	$ (671)	$ 4	(675)
Common stock, shares outstanding, ending balance at Dec. 31, 2018	17,302,037	17,302,000
Stockholders' equity, ending balance at Dec. 31, 2018	$ 448,184	$ 1,081	119,888	355,524	(28,309)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	69,118			69,118
Total other comprehensive income (loss), net of tax	17,072				17,072
Cash dividends declared	(35,001)			(35,001)
Share-based compensation	3,124		3,124
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered, shares		61,000
Exercise of stock options, issuance of other compensation-related equity awards, net of awards surrendered	$ 273	$ 4	269
Common stock, shares outstanding, ending balance at Dec. 31, 2019	17,363,455	17,363,000
Stockholders' equity, ending balance at Dec. 31, 2019	$ 503,492	$ 1,085	$ 123,281	390,363	$ (11,237)
Cumulative effect of change in accounting principle	$ 722			$ 722

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per share (in dollars per share)	$ 0.51	$ 0.51	$ 0.51	$ 0.47	$ 0.47	$ 0.43	$ 0.43	$ 0.43	$ 2	$ 1.76	$ 1.54

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income		$ 69,118	$ 68,432	$ 45,925
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses		1,575	1,550	2,600
Depreciation of premises and equipment		3,291	3,282	3,454
Net amortization of premiums and discounts on securities and loans		4,492	2,865	3,426
Amortization of intangibles		943	979	1,035
Goodwill impairment		0	0	150
Share–based compensation		3,124	2,602	2,577
Tax benefit from stock option exercises and other equity awards		248	496	508
Deferred income tax (benefit) expense		(1,491)	(63)	5,687
Income from bank-owned life insurance	[1]	(2,354)	(2,196)	(2,161)
Net gains on loan sales, including fair value adjustments		(14,332)	(9,749)	(10,991)
Net realized losses on securities	[1]	53	0	0
Proceeds from sales of loans, net		530,713	391,960	472,556
Loans originated for sale		(525,675)	(378,896)	(461,262)
Change in fair value of contingent consideration liability		0	(187)	(643)
Decrease in operating lease right-of-use assets		2,131	0	0
Decrease in operating lease liabilities		(1,992)	0	0
Increase in other assets		(27,961)	(7,456)	(8,794)
Increase in other liabilities		31,552	9,257	5,318
Net cash provided by (used in) operating activities		73,435	82,876	59,385
Cash flows from investing activities:
Purchases of mortgage-backed available for sale debt securities		(178,797)	(175,539)	(89,194)
Purchases of other available for sale debt securities		(27,520)	(76,264)	(59,940)
Proceeds from sale of other available for sale debt securities		11,877	0	0
Maturities and principal payments of mortgage-backed available for sale debt securities		147,620	83,197	84,381
Maturities and principal payments of other available for sale debt securities		108,306	7,301	22,071
Maturities and principal payments of mortgage-backed held to maturity debt securities		0	2,029	2,950
(Purchases) remittance of Federal Home Loan Bank stock		(4,785)	(5,551)	2,612
Net increase in loans		(154,502)	(306,299)	(120,582)
Purchases of loans		(60,465)	(1,780)	(20,278)
Proceeds from the sale of property acquired through foreclosure or repossession		2,000	49	1,053
Purchases of premises and equipment		(3,132)	(3,974)	(2,779)
Proceeds from sale of premises		213	0	0
Purchases of bank-owned life insurance		0	(5,000)	0
Proceeds from bank-owned life insurance		326	0	0
Equity investment in real estate limited partnership		(1,256)	0	0
Net cash provided by (used in) investing activities		(160,115)	(481,831)	(179,706)
Cash flows from financing activities:
Net (decrease) increase in deposits		(25,166)	281,341	178,955
Proceeds from Federal Home Loan Bank advances		1,982,000	2,040,000	1,352,501
Repayment of Federal Home Loan Bank advances		(1,791,258)	(1,880,634)	(1,410,075)
Payment of contingent consideration liability		0	(1,217)	0
Net proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered		273	(671)	366
Cash dividends paid		(34,189)	(29,312)	(26,300)
Net cash provided by (used in) financing activities		131,660	409,507	95,447
Net increase (decrease) in cash and cash equivalents		44,980	10,552	(24,874)
Cash and cash equivalents at beginning of year		93,475	82,923	107,797
Cash and cash equivalents at end of year		138,455	93,475	82,923
Noncash Activities:
Loans charged-off		2,020	1,187	2,462
Loans transferred to property acquired through foreclosure or repossession		2,000	3,074	576
Operating lease right-of-use assets		28,923	0	0
Operating lease liabilities		30,853	0	0
Fair value of held-to-maturity securities transferred to available for sale		10,316	0	0
Supplemental Disclosures:
Interest payments		64,496	41,285	29,687
Income tax payments		$ 19,759	$ 17,148	$ 25,988
[1]	As reported in the Consolidated Statements of Income.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation Washington Trust Bancorp, Inc. (the “Bancorp”) is a publicly-owned registered bank holding company that has elected to be a financial holding company. The Bancorp’s subsidiaries include The Washington Trust Company, of Westerly (the “Bank”), a Rhode Island chartered commercial bank founded in 1800, and Weston Securities Corporation (“WSC”). Through its subsidiaries, the Bancorp offers a complete product line of financial services including commercial, residential and consumer lending, retail and commercial deposit products, and wealth management services through its offices in Rhode Island, eastern Massachusetts and Connecticut. The consolidated financial statements include the accounts of the Bancorp and its subsidiaries (collectively, the “Corporation” or “Washington Trust”). All intercompany balances and transactions have been eliminated in consolidation. The Bancorp also owns the common stock of two capital trusts, which have issued trust preferred securities. These capital trusts are variable interest entities in which the Bancorp is not the primary beneficiary and, therefore, are not consolidated. The capital trust’s only assets are junior subordinated debentures issued by the Bancorp, which were acquired by the capital trusts using the proceeds from the issuance of the trust preferred securities and common stock. The Bancorp’s equity interest in the capital trusts, classified in other assets, and the junior subordinated debentures are included in the Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is included in the Consolidated Statements of Income. The accounting and reporting policies of the Corporation conform to accounting principles generally accepted in the United States of America (“GAAP”) and to general practices of the banking industry. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the balance sheet and revenues and expenses for the period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to change are the determination of the allowance for loan losses, the valuation of goodwill and identifiable intangible assets, the assessment of investment securities for impairment and the accounting for defined benefit pension plans. Short-term Investments Short-term investments consist of highly liquid investments with a maturity date of three months or less when purchased and are considered to be cash equivalents. The Corporation’s short-term investments may be composed of overnight federal funds sold, securities purchased under resale agreements, money market mutual funds and U.S. Treasury bills. Securities Management determines the appropriate classification of securities at the time of purchase. Investments in debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and carried at amortized cost. Investments not classified as held to maturity are classified as available for sale. Securities available for sale consist of debt securities that are available for sale to respond to changes in market interest rates, liquidity needs, changes in funding sources and other similar factors. These assets are specifically identified and are carried at fair value. Changes in fair value of available for sale securities, net of applicable income taxes, are reported as a separate component of shareholders’ equity. Washington Trust does not have a trading portfolio. Premiums and discounts are amortized and accreted over the term of the securities on a method that approximates the level yield method. The amortization and accretion is included in interest income on securities. Interest income is recognized when earned. Realized gains or losses from sales of securities are recorded on the trade date and are determined using the specific identification method. The fair values of securities may be based on either quoted market prices or third party pricing services. When the fair value of an investment security is less than its amortized cost basis, the Corporation assesses whether the decline in value is other-than-temporary. The Corporation considers whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for impairment, the severity and duration of the impairment, changes in the value subsequent to the reporting date, forecasted performance of the issuer, changes in the dividend or interest payment practices of the issuer, changes in the credit rating of the issuer or the specific security, and the general market condition in the geographic area or industry in which the issuer operates. In determining whether an other-than-temporary impairment has occurred for debt securities, the Corporation compares the present value of cash flows expected to be collected from the security with the amortized cost of the security. If the present value of expected cash flows is less than the amortized cost of the security, then the entire amortized cost of the security will not be recovered; that is, a credit loss exists, and an other-than-temporary impairment shall be considered to have occurred. The credit loss component of an other-than-temporary impairment write-down for debt securities is recorded in earnings while the remaining portion of the impairment loss is recognized, net of tax, in other comprehensive income provided that the Corporation does not intend to sell the underlying debt security and it is more-likely-than-not that the Corporation would not have to sell the debt security prior to recovery of the unrealized loss, which may be to maturity. If the Corporation intended to sell any securities with an unrealized loss or it is more-likely-than-not that the Corporation would be required to sell the investment securities before recovery of their amortized cost basis, then the entire unrealized loss would be recorded in earnings. Federal Home Loan Bank Stock The Bank is a member of the FHLB. The FHLB is a cooperative that provides services, including funding in the form of advances, to its member banking institutions. As a requirement of membership, the Bank must own a minimum amount of FHLB stock, calculated periodically based primarily on its level of borrowings from the FHLB. No market exists for shares of FHLB stock and therefore, it is carried at cost. FHLB stock may be redeemed at par value five years following termination of FHLB membership, subject to limitations which may be imposed by the FHLB or its regulator, the Federal Housing Finance Board, to maintain capital adequacy of the FHLB. While the Bank currently has no intentions to terminate its FHLB membership, the ability to redeem its investment in FHLB stock would be subject to the conditions imposed by the FHLB. The Bank monitors its investment to determine if impairment exists. Based on the capital adequacy and the liquidity position of the FHLB, management believes there is no impairment related to the carrying amount of FHLB stock included in the Consolidated Balance Sheet as of December 31, 2019 . Mortgage Banking Activities Mortgage Loans Held for Sale Residential mortgage loans originated and intended for sale in the secondary market are classified as held for sale. Accounting Standards Codification (“ASC”) 825, “Financial Instruments” allows for the irrevocable option to elect fair value accounting for the initial and subsequent measurement for certain financial assets and liabilities on a contract-by-contract basis that may otherwise not be required to be measured at fair value under other accounting standards. The Corporation has elected the fair value option for mortgage loans held for sale in order to better match changes in fair values of the loans with changes in the fair value of the derivative forward sale commitment contracts used to economically hedge them. Changes in the fair value of mortgage loans held for sale accounted for under the fair value option are recorded in earnings and are partially offset by changes in fair value of forward sale commitments. These changes in fair value are included in mortgage banking revenues. Gains and losses on residential loan sales are recognized at the time of sale and included in mortgage banking revenues. Upfront fees and costs related to mortgage loans held for sale for which the fair value option was elected are recognized in mortgage banking revenues as received / incurred and are not deferred. Commissions received on mortgage loans brokered to various investors are recognized when received and included in mortgage banking revenues. Loan Servicing Rights When mortgage loans held for sale are sold with servicing retained, mortgage servicing right assets are recognized as separate assets. Mortgage servicing rights are originally recorded at fair value. Fair value is based on a valuation model that incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, ancillary income, prepayment speeds, and default rates and losses. Mortgage servicing rights are included in other assets. Mortgage servicing rights are amortized as an offset to mortgage banking revenues over the period of estimated net servicing income. They are periodically evaluated for impairment based on their fair value. Impairment is measured on an aggregated basis by stratifying the rights based on homogeneous characteristics such as note rate and loan type. The fair value is estimated based on the present value of expected cash flows, incorporating assumptions for discount rate, prepayment speed and servicing cost. Any impairment is recognized through a valuation allowance and as a reduction to mortgage banking revenues. Loans Portfolio Loans Loans are carried at the principal amount outstanding, adjusted by partial charge-offs and net of unamortized deferred loan origination fees and costs. Interest income is accrued on a level yield basis based upon principal amounts outstanding, except for loans on nonaccrual status. Deferred loan origination fees and costs are amortized as an adjustment to yield over the term of the related loans. For purchased loans, which did not show signs of credit deterioration at the time of purchase, interest income is also accrued on a level yield basis based upon principal amounts outstanding and is then further adjusted by accretion of any discount or amortization of any premium associated with the loans. Nonaccrual Loans Loans, with the exception of certain well-secured loans that are in the process of collection, are placed on nonaccrual status and interest recognition is suspended when such loans are 90 days or more overdue with respect to principal and/or interest, or sooner if considered appropriate by management. Well-secured loans are permitted to remain on accrual status provided that full collection of principal and interest is assured and the loan is in the process of collection. Loans are also placed on nonaccrual status when, in the opinion of management, full collection of principal and interest is doubtful. When loans are placed on nonaccrual status, interest previously accrued but not collected is reversed against current period income. Subsequent interest payments received on nonaccrual loans are applied to the outstanding principal balance of the loan or recognized as interest income depending on management’s assessment of the ultimate collectability of the loan. Loans are removed from nonaccrual status when they have been current as to principal and interest for a period of time, the borrower has demonstrated an ability to comply with repayment terms, and when, in management’s opinion, the loans are considered to be fully collectible. Troubled Debt Restructured Loans Loans are considered to be troubled debt restructurings when the Corporation has granted concessions to a borrower due to the borrower’s financial condition that it otherwise would not have considered. These concessions may include modifications of the terms of the debt such as deferral of payments, extension of maturity, reduction of principal balance, reduction of the stated interest rate other than normal market rate adjustments, or a combination of these concessions. Debt may be bifurcated with separate terms for each tranche of the restructured debt. Restructuring of a loan in lieu of aggressively enforcing the collection of the loan may benefit the Corporation by increasing the ultimate probability of collection. Restructured loans are classified as accruing or non-accruing based on management’s assessment of the collectability of the loan. Loans which are already on nonaccrual status at the time of the restructuring generally remain on nonaccrual status for approximately six months before management considers such loans for return to accruing status. Accruing restructured loans are placed into nonaccrual status if and when the borrower fails to comply with the restructured terms and management deems it unlikely that the borrower will return to a status of compliance in the near term. Troubled debt restructurings are reported as such for at least one year from the date of the restructuring. In years after the restructuring, troubled debt restructured loans are removed from this classification if the restructuring did not involve a below-market rate concession and the loan is not deemed to be impaired based on the terms specified in the restructuring agreement. Impaired Loans A loan is considered impaired when, based on current information and events, it is probable that the Corporation will not be able to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Impaired loans are evaluated on an individual basis and include nonaccrual loans and loans restructured in a troubled debt restructuring. Allowance for Loan Losses The allowance for loan losses is management’s best estimate of the risk of loss inherent in the loan portfolio as of the balance sheet date. The allowance is increased by provisions charged to earnings and by recoveries of amounts previously charged-off, and is reduced by charge-offs on loans. Loan charge-offs are recognized when management believes the collectability of the principal balance outstanding is unlikely. Full or partial charge-offs on collateral dependent impaired loans are generally recognized when the collateral is deemed to be insufficient to support the carrying value of the loan. The level of the allowance is based on management’s ongoing review of the growth and composition of the loan portfolio, historical loss experience, estimated loss emergence period (the period from the event that triggers the eventual default until the actual loss is recognized with a charge-off), current economic conditions, analysis of asset quality and credit quality levels and trends, the performance of individual loans in relation to contract terms and other pertinent factors. A methodology is used to systematically measure the amount of estimated loan loss exposure inherent in the loan portfolio for the purposes of establishing a sufficient allowance for loan losses. The methodology includes: (1) the identification of loss allocations for individual loans deemed to be impaired and (2) the application of loss allocation factors for non-impaired loans based on historical loss experience and estimated loss emergence period, with adjustments for various exposures that management believes are not adequately represented by historical loss experience. Loss allocations for loans deemed to be impaired are measured using a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or, if the loan is collateral dependent, at the fair value of the collateral. For collateral dependent loans for which repayment is dependent on the sale of the collateral, management adjusts the fair value for estimated costs to sell. For collateral dependent loans for which repayment is dependent on the operation of the collateral, such as accruing troubled debt restructured loans, estimated costs to sell are not incorporated into the measurement. Management may also adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of circumstances associated with the property. For loans that are collectively evaluated, loss allocation factors are derived by analyzing historical loss experience by loan segment over an established look-back period deemed to be relevant to the inherent risk of loss in the portfolios. Loans are segmented by loan type, collateral type, delinquency status and loan risk rating, where applicable. These loss allocation factors are adjusted to reflect the loss emergence period. These amounts are supplemented by certain qualitative risk factors reflecting management’s view of how losses may vary from those represented by historical loss rates. These qualitative risk factors include: 1) changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; 2) changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; 3) changes in the nature and volume of the portfolio and in the terms of loans; 4) changes in the experience, ability, and depth of lending management and other relevant staff; 5) changes in the volume and severity of past due loans, the volume of nonaccrual loans, and the volume and severity of adversely classified or rated loans; 6) changes in the quality of the institution’s loan review system; 7) changes in the value of underlying collateral for collateral dependent loans; 8) the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and 9) the effect of other external factors such as legal and regulatory requirements on the level of estimated credit losses in the institution’s existing portfolio. Because the methodology is based upon historical experience and trends, current economic data, as well as management’s judgment, factors may arise that result in different estimations. Adversely different conditions or assumptions could lead to increases in the allowance. In addition, various regulatory agencies periodically review the allowance for loan losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination. The allowance is an estimate, and ultimate losses may vary from management’s estimate. Changes in the estimate are recorded in the results of operations in the period in which they become known, along with provisions for estimated losses incurred during that period. Premises and Equipment Land is carried at cost. Premises and equipment are carried at cost less accumulated depreciation. Depreciation for financial reporting purposes is calculated on the straight-line method over the estimated useful lives of assets. Leasehold improvements are depreciated over the shorter of the lease terms or the estimated useful lives of the improvements. Expected terms include lease renewal options to the extent that the exercise of such renewals is reasonably assured. Expenditures for major additions and improvements are capitalized while the costs of current maintenance and repairs are charged to operating expenses. The estimated useful lives of premises and improvements range from 5 to 40 years. For furniture, fixtures and equipment, the estimated useful lives range from 3 to 20 years. Leases The Corporation has committed to rent premises used in business operations under non-cancelable operating leases and determines if an arrangement meets the definition of a lease upon inception. Prior to January 1, 2019, operating leases were accounted for under ASC 840, Leases, and were considered off-balance sheet commitments as neither an asset or liability was recognized in the Consolidated Balance Sheets. Effective January 1, 2019, the Corporation adopted the provisions of ASC 842, Leases, as further disclosed in Note 2. ASC 842 requires operating leases to be recorded on the balance sheet, through the recognition of an operating lease right-of-use asset (“ROU”) and an operating lease liability at the commencement date of the new lease. ROU assets represent a right to use an underlying asset for the contractual lease term. Operating lease liabilities represent an obligation to make lease payments arising from the lease. The Corporation’s leases do not provide an implicit interest rate, therefore the Corporation uses its incremental collateralized borrowing rates commensurate with the underlying lease terms to determine the present value of operating lease liabilities. The Corporation’s operating lease agreements contain both lease and non-lease components, which are generally accounted for separately. The Corporation’s lease agreements do not contain any residual value guarantees. Operating leases with terms of 12 months or less are included in ROU assets and operating lease liabilities recorded in the Corporation’s Consolidated Balance Sheets. Operating lease terms include options to extend when it is reasonably certain that the Corporation will exercise such options, determined on a lease-by-lease basis. Under both ASC 840 and ASC 842, rental expense for operating leases is recognized on a straight-line basis over the lease term. Variable lease components, such as consumer price index adjustments, are expensed as incurred and not included in ROU assets and operating lease liabilities. Goodwill and Identifiable Intangible Assets Goodwill represents the excess of the purchase price over the net fair value of the acquired businesses. Goodwill is not amortized but is tested for impairment at the reporting unit level, defined as the segment level, at least annually in the fourth quarter or more frequently whenever events or circumstances occur that indicate that it is more-likely-than-not that an impairment loss has occurred. In assessing impairment, the Corporation has the option to perform a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of such events or circumstances, we determine it is not more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, then we would not be required to perform an impairment test. The quantitative impairment analysis requires a comparison of each reporting unit’s fair value to its carrying value to identify potential impairment. Goodwill impairment exists when a reporting unit’s carrying value of goodwill exceeds its implied fair value. Significant judgment is applied when goodwill is assessed for impairment. This judgment includes, but may not be limited to, the selection of appropriate discount rates, the identification of relevant market comparables and the development of cash flow projections. The selection and weighting of the various fair value techniques may result in a higher or lower fair value. Judgment is applied in determining the weightings that are most representative of fair value. Intangible assets identified in acquisitions consist of advisory contracts. The value attributed to intangible assets was based on the time period over which they are expected to generate economic benefits. Intangible assets are amortized over their estimated lives using a method that approximates the amount of economic benefits that are realized by the Corporation. Intangible assets with definite lives are tested for impairment whenever events or circumstances occur that indicate that the carrying amount may not be recoverable. If applicable, the Corporation tests each of the intangibles by comparing the carrying value of the intangible asset to the sum of undiscounted cash flows expected to be generated by the asset. If the carrying amount of the asset exceeds its undiscounted cash flows, then an impairment loss would be recognized for the amount by which the carrying amount exceeds its fair value. Impairment would result in a write-down to the estimated fair value based on the anticipated discounted future cash flows. The remaining useful life of the intangible assets that are being amortized is also evaluated to determine whether events and circumstances warrant a revision to the remaining period of amortization. Impairment of Long - Lived Assets Other than Goodwill Long-lived assets, including premises and equipment, are reviewed for impairment whenever events or changes in business circumstances indicate that the carrying amount may not be fully recoverable. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal. Property Acquired through Foreclosure or Repossession Property acquired through foreclosure or repossession is carried at the lower of cost or fair value less estimated costs to sell. Fair value of such assets is determined based on independent appraisals and other relevant factors. Any write-down to fair value at the time of foreclosure or repossession is charged to the allowance for loan losses. Subsequent to foreclosure or repossession, a valuation allowance is maintained for declines in market value and for estimated selling expenses. Upon sale of foreclosed property, any excess of the carrying value over the sales proceeds is recognized as a loss on sale. Any excess of sales proceeds over the carrying value of the foreclosed property is first applied as a recovery to the valuation allowance, if any, with the remainder being recognized as a gain on sale. Changes to the valuation allowance, expenses associated with ownership of these properties, and gains and losses from their sale are included in foreclosed property costs. Loans that are substantively repossessed include only those loans for which the Corporation has obtained control of the collateral, but has not completed legal foreclosure proceedings. Bank-Owned Life Insurance The investment in BOLI represents the cash surrender value of life insurance policies on the lives of certain employees who have provided positive consent allowing the Bank to be the beneficiary of such policies. Increases in the cash value of the policies, as well as insurance proceeds received, are recorded in noninterest income and are not subject to income taxes. The financial strength of the insurance carrier is reviewed prior to the purchase of BOLI and annually thereafter. Investment in Real Estate Limited Partnerships The Bank has a 99.9% ownership interest in three real estate limited partnerships that renovate, own and operate three low-income housing complexes. The Bank neither actively participates nor has a controlling interest in these limited partnerships. The carrying value of these investments is recorded in other assets on the Consolidated Balance Sheets. Investments made prior to January 1, 2015 are accounted for under the equity method of accounting. Net losses generated by the partnership are recorded as a reduction to the Bank’s investment and as a reduction of other noninterest income in the Consolidated Statements of Income. Tax credits generated by the partnerships are recorded as a reduction in the income tax provision in the year they are allowed for tax reporting purposes. The results of operations of the real estate limited partnerships are periodically reviewed to determine if the partnership generates sufficient operating cash flow to fund its current obligations. In addition, the current value of the underlying properties is compared to the outstanding debt obligations. If it is determined that the investment is permanently impaired, the carrying value would be written down to the estimated realizable value. Investments made after January 1, 2015 are accounted for using the proportional amortization method. Unfunded commitments for future capital contributions are recognized and recorded in other liabilities on the Consolidated Balance Sheets. Under the proportional amortization method, the investment is amortized over the same tax period and in proportion to the total tax benefits expected to be allocated to the Bank. The amortization is recognized as a component of income tax expense in the Consolidated Statements of Income. In addition, operating losses and tax credits generated by the partnership are also recorded as a reduction to income tax expense. Transfers and Servicing of Assets and Extinguishments of Liabilities The accounting for transfers and servicing of financial assets and extinguishments of liabilities is based on consistent application of a financial components approach that focuses on control. This approach distinguishes transfers of financial assets that are sales from transfers that are secured borrowings. Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Corporation, (2) the transferee obtains the right to pledge or exchange the transferred assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Corporation, and (3) the Corporation does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. If a transfer does not meet the criteria for a sale, the transfer is accounted for as a secured borrowing with a pledge of collateral. Wealth Management Assets Under Administration Assets under administration represent assets held in a fiduciary or agency capacity for wealth management clients and are not included in the Consolidated Balance Sheets, as these are not assets of the Corporation. Revenue from Contracts with Customers Prior to January 1, 2018, fee revenue such as wealth management revenues and service charges on deposit accounts were recognized when earned or to the extent services were completed. Effective January 1, 2018, the Corporation adopted the provisions of ASC 606, Revenue from Contracts with Customers. ASC 606 provides a revenue recognition framework for contracts with customers unless those contracts are within the scope of other accounting standards. Revenue from contracts with customers is measured based on the consideration specified in the contract with a customer. The Corporation recognizes revenue from contracts with customers when it satisfies its performance obligations. The performance obligations are generally satisfied as services are rendered and can either be satisfied at a point in time or over time. The Corporation recognizes revenue that is transactional in nature and such revenue is earned at a point in time. Revenue that is recognized at a point in time includes card interchange fees (fee income related to debit card transactions), ATM fees, wire transfer fees, overdraft charge fees, and stop-payment and returned check fees. Such revenue is derived from transactional information and is recognized as revenue immediately as the transactions occur or upon providing the service to complete the customer’s transaction. The Corporation recognizes revenue over a period of time, generally monthly, as services are performed and performance obligations are satisfied. Such revenue includes wealth management revenues and service charges on deposit accounts. Wealth management revenues are categorized as either asset-based revenues or transaction-based revenues. Asset-based revenues include trust and investment management fees that are earned based upon a percentage of asset values under administration. Transaction-based revenues include financial planning fees, tax preparation fees, commissions and other service fees. Fee revenue from service charges on deposit accounts represent the service charges assessed to customers who hold deposit accounts at the

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2019
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Accounting Standards Adopted in 2019 Leases - Topic 842 Accounting Standards Update No. 2016-02, “Leases” (“ASU 2016-02”), was issued in February 2016 and provides revised guidance related to the accounting and reporting of leases. ASU 2016-02 requires lessees to recognize most leases on the balance sheet. The recognition, measurement and presentation of expenses and cash flows arising from a lease by a lessee depends on its classification as a finance or operating lease. ASU 2016-02 requires a modified retrospective transition, with a package of practical expedients that entities may elect to apply. In January 2018, Accounting Standards Update No. 2018-01, “Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842” was issued to address concerns about the costs and complexity of complying with the transition provisions of ASU 2016-02. In July 2018, Accounting Standards Update No. 2018-10, “Codification Improvements to Topic 842, Leases” was issued to provide more detailed guidance and additional clarification for implementing ASU 2016-02. Also in July 2018, Accounting Standards Update No. 2018-11, “Targeted Improvements” (“ASU 2018-11”) was issued and allows for an optional transition method in which the provisions of Topic 842 would be applied upon the adoption date and would not have to be retroactively applied to the earliest reporting period presented in the consolidated financial statements. The Corporation used this optional transition method for the adoption of Topic 842. In December 2018, Accounting Standards Update No. 2018-20, “Leases (Topic 842) Narrow-Scope Improvement for Lessors” was issued to address lessors’ concerns about sales taxes and other similar taxes collected from lessees, certain lessor costs, and recognition of variable payments for contracts with lease and non-lease components. These ASUs were effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2018. The project team that was assembled to address the changes pursuant to Topic 842 identified and reviewed all in scope lease agreements. The Corporation rents premises used in business operations under non-cancelable operating leases, which as of December 31, 2018 were not reflected in its Consolidated Balance Sheets. The Corporation has no finance leases. The Corporation adopted Topic 842 “Leases” effective January 1, 2019 and has applied the guidance to all operating leases within the scope of Topic 842 at that date. The Corporation elected to adopt the package of practical expedients, which among other things, does not require reassessment of lease classification. Upon adoption, the Corporation recognized $28.9 million in operating lease right-of-use-assets, $30.9 million in operating lease liabilities, a reduction in rent-related liabilities of $2.9 million , a reduction of net deferred tax assets of $222 thousand and a cumulative effect adjustment (net of taxes) that increased beginning retained earnings by $722 thousand in the Consolidated Balance Sheets. The cumulative effect adjustment represented the recognition of unamortized deferred gains associated with two leases. There was no change to the timing in recognition of operating lease rent expense in the Corporation’s consolidated financial statements associated with leases. In March 2019, Accounting Standards Update No. 2019-01, “Leases (Topic 842) Codification Improvements” (“ASU 2019-01”) was issued to address lessors’ concerns about determining fair value of underlying leased assets and presentation issues in the statement of cash flows for sales-type and direct financing leases. ASU 2019-01 also clarified for both lessees and lessors that transition disclosures related to Topic 250 were not required for annual periods are also not required for interim periods. ASU 2019-01 was effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2019, with early adoption permitted. The Corporation early adopted this ASU 2019-01 effective January 1, 2019 and it did not have a material impact on the Corporation’s consolidated financial statements. Derivatives and Hedging - Topic 815 Accounting Standards Update No. 2017-12, “Targeted Improvements to Accounting for Hedging Activities” (“ASU 2017-12”), was issued in August 2017 to better align financial reporting for hedging activities with the economic objectives of those activities. ASU 2017-12 was effective for fiscal years beginning after December 15, 2018, with early adoption, including adoption in an interim period, permitted. In addition, ASU 2017-12 also permitted the reclassification of eligible securities from the held to maturity classification to the available for sale classification. The Corporation adopted the provisions of ASU 2017-12 on January 1, 2019 using a modified retrospective transition method. As permitted by ASU 2017-12, qualifying debt securities classified as held to maturity with an amortized cost of $10.4 million and a fair value of $10.3 million were reclassified to available for sale upon the adoption date. An unrealized loss of $75 thousand (net of taxes) was recognized in the accumulated other comprehensive income component of shareholders’ equity at the date of adoption. The adoption of ASU 2017-12 did not have a material impact on the Corporation’s consolidated financial statements. Accounting Standards Update No. 2018-16, “Inclusion of the Secured Overnight Financing Rate (SOFR) Overnight Index Swap (OIS) Rate as a Benchmark Interest Rate for Hedge Accounting Purposes” (“ASU 2018-16”), was issued in October 2018 to permit the use of the Overnight Index Swap rate based on the Secured Overnight Financing Rate as a U.S. benchmark interest rate for hedge accounting purposes under Topic 815 in addition to existing benchmark interest rates that are currently used for hedge accounting. ASU 2018-16 was effective for fiscal years beginning after December 15, 2018, and interim periods with those fiscal years. The provisions required prospective application for qualifying new or re-designated hedging relationships entered into on or after the date of adoption. The Corporation adopted the provisions of ASU 2018-16 on January 1, 2019 and it did not have a material impact on the Corporation’s consolidated financial statements. Accounting Standards Pending Adoption Financial Instruments - Credit Losses - Topic 326 Accounting Standards Update No. 2016-13, “Financial Instruments - Credit Losses” (“ASU 2016-13”), was issued in June 2016. ASU 2016-13 requires the measurement of expected lifetime credit losses for financial assets measured at amortized cost, as well as off-balance sheet credit exposures at the reporting date. The measurement is based on historical experience, current conditions, and reasonable and supportable forecasts and requires enhanced disclosures related to the significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an organization’s portfolio. In addition, ASU 2016-13 amends the accounting for credit losses on available for sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 provides for a modified retrospective transition, resulting in a cumulative-effect adjustment to equity as of the beginning of the period in which the guidance is effective, except for debt securities for which an other-than-temporary impairment has previously been recognized. For these debt securities, a prospective transition approach will be adopted in order to maintain the same amortized cost prior to and subsequent to the effective date of ASU 2016-13. This ASU is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2019. The Corporation will adopt ASU 2016-13, including the subsequent ASUs issued to clarify Topic 326 (“Topic 326”), on January 1, 2020. In April 2019, Accounting Standards Update No. 2019-04, “Codification Improvements to Topic 326 Financial Instruments - Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments” was issued to provide additional clarification on the scope and disclosure requirements of Topic 326. This ASU includes provisions related to accounting policy elections that can be made by the entity related to accrued interest receivable and expected prepayments on financial assets, the inclusion of recoveries in estimating the allowance for credit losses (“ACL”) and consideration of contract extension and renewals when determining the contractual term. This ASU also provides clarification on the tabular vintage disclosures related to line-of-credit arrangements that convert term loans. In November 2019, Accounting Standards Update No. 2019-11, “Codification Improvements to Topic 326, Financial Instruments-Credit Losses” was issued to further additional clarification on the adoption of Topic 326. The effective dates of these ASUs are the same as the effective date of ASU 2016-13. The Corporation assembled a cross-functional project team that met regularly to address the additional data requirements, to determine the approach for implementation and to identify new internal controls over enhanced accounting processes for estimating the ACL. This included assessing the adequacy of existing loan and loss data, as well as assessing models for default and loss estimates. The Corporation has completed the development of its ACL methodology. To estimate the ACL for loans and off-balance sheet credit exposures, such as unfunded loan commitments, the Corporation will utilize a discounted cash flow model that contains additional assumptions to calculate credit losses over the estimated life of financial assets and off-balance sheet credit exposures and will include the impact of forecasted economic conditions. The estimate is expected to include a one-year reasonable and supportable forecast period and thereafter a one-year reversion period to the historical mean of its macroeconomic assumption. The estimate will also include qualitative factors that may not be reflected in quantitatively derived results to ensure that the ACL reflects a reasonable estimate of current expected credit losses. Based on the credit quality of our existing available for sale debt securities portfolio, which primarily consists of obligations of U.S. government agency and U.S. government-sponsored enterprise securities, including mortgage-backed securities, the Corporation does not expect the adoption of ASU 2016-13, as it relates to debt securities, to be significant. For available for sale debt securities with unrealized losses, credit losses will be recognized as an allowance rather than a reduction in the amortized cost of the securities. As a result, improvements to estimated credit losses will be recognized immediately in earnings rather than as interest income over time. The project team completed limited “trial” runs and analytical reviews through the year ended December 31, 2019. The Corporation expects to complete independent model validation and to finalize its documentation of ACL processes and controls in the first quarter of 2020. Upon adoption of Topic 326 on January 1, 2020, the Corporation currently expects to recognize a total increase in the ACL for loans (a contra-asset) and in the ACL for off-balance sheet credit exposures (a liability) in the range of $5.5 million to $8.5 million , an increase in its net deferred tax assets in the range of $1.3 million to $2.0 million , and a one-time cumulative-effect adjustment that decreases retained earnings in the range of $4.2 million to $6.5 million (net of tax). The Corporation also plans to elect the regulatory capital transition relief issued by the FDIC to provide banking organizations the option to phase in over a three-year period the day-one adverse effects on regulatory capital resulting from the adoption of Topic 326. The adoption of Topic 326 is not expected to have a material impact on the Corporation’s and the Bank’s regulatory capital. Fair Value Measurement - Topic 820 Accounting Standards Update No. 2018-13, “Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”), was issued in August 2018 to modify the disclosure requirements related to fair value. ASU 2018-13 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted, including adoption in an interim period. Certain provisions under ASU 2018-13 require prospective application, while other provisions require retrospective application to all periods presented in the consolidated financial statements upon adoption. The Corporation will adopt ASU 2018-13 on January 1, 2020 and this ASU is not expected to have a material impact on the Corporation’s consolidated financial statements. Compensation - Retirement Benefits - Topic 715 Accounting Standards Update No. 2018-14, “Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans” (“ASU 2018-14”), was issued in August 2018 to modify the disclosure requirements associated with defined benefit pension plans and other postretirement plans. ASU 2018-14 is effective for fiscal years ending after December 15, 2020, with early adoption permitted. The provisions under ASU 2018-14 are required to be applied retrospectively. The adoption of ASU 2018-14 is not expected to have a material impact on the Corporation’s consolidated financial statements. Intangibles - Goodwill and Other - Internal-Use Software - Topic 350 Accounting Standards Update No. 2018-15, “Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract” (“ASU 2018-15”), was issued in August 2018 to align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with those requirements that currently exist in GAAP for capitalizing implementation costs incurred to develop or obtain internal-use software. Implementation costs would either be capitalized or expensed as incurred depending on the project stage. All costs in the preliminary and post-implementation project stages are expensed as incurred, while certain costs within the application development stage are capitalized. The provisions under ASU 2018-15 can either be applied retrospectively or prospectively. ASU 2018-15 is effective for fiscal years beginning after December 15, 2019, with early adoption permitted, including adoption in an interim period. The Corporation will adopt ASU 2018-15 on January 1, 2020 on a prospective basis. ASU 2018-15 is not expected to have a material impact on the Corporation’s consolidated financial statements. Income Taxes - Topic 745 Accounting Standards Update No. 2019-12, “Income Taxes (Topic 740) - Simplifying the Accounting for Income Taxes” (“ASU 2019-12”), was issued in December 2019 to simplify the accounting for income taxes. ASU 2019-12 is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. Certain provisions under ASU 2019-12 require prospective application, some require modified retrospective application through a cumulative-effect adjustment to retained earnings as of the beginning of the year of adoption, while other provisions require retrospective application to all periods presented in the consolidated financial statements upon adoption. The Corporation is currently evaluating the effect that this ASU will have on the Corporation’s consolidated financial statements.

Cash and Due from Banks

Cash and Due from Banks	12 Months Ended
	Dec. 31, 2019
Cash and Cash Equivalents [Abstract]
Cash and Due from Banks	Cash and Due from Banks The Bank maintains certain average reserve balances to meet the requirements of the Board of Governors of the FRB. Some or all of these reserve requirements may be satisfied with vault cash. Reserve balances amounted to $27.9 million and $21.6 million , respectively, at December 31, 2019 and 2018 and were included in cash and due from banks in the Consolidated Balance Sheets. As of December 31, 2019 and 2018 , cash and due from banks includes interest-bearing deposits in other banks of $83.4 million and $33.7 million , respectively. See Note 13 for additional disclosure regarding cash collateral pledged to derivative counterparties.

Securities

Securities	12 Months Ended
	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Securities	Securities The following tables present the amortized cost, gross unrealized holding gains, gross unrealized holding losses and fair value of securities by major security type and class of security: (Dollars in thousands) December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $157,255 $626 ($233 ) $157,648 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 713,553 8,491 (2,964 ) 719,080 Individual name issuer trust preferred debt securities 13,324 — (745 ) 12,579 Corporate bonds 11,141 — (958 ) 10,183 Total available for sale debt securities $895,273 $9,117 ($4,900 ) $899,490 Total securities $895,273 $9,117 ($4,900 ) $899,490 (Dollars in thousands) December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $246,708 $442 ($4,467 ) $242,683 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 675,368 1,943 (16,518 ) 660,793 Obligations of states and political subdivisions 935 2 — 937 Individual name issuer trust preferred debt securities 13,307 — (1,535 ) 11,772 Corporate bonds 13,402 — (1,777 ) 11,625 Total available for sale debt securities $949,720 $2,387 ($24,297 ) $927,810 Held to Maturity Debt Securities: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $10,415 $— ($99 ) $10,316 Total held to maturity debt securities 10,415 — (99 ) 10,316 Total securities $960,135 $2,387 ($24,396 ) $938,126 As discussed in Note 2 , on January 1, 2019, the Corporation adopted ASU 2017-12. As permitted by ASU 2017-12, qualifying debt securities classified as held to maturity with an amortized cost of $10.4 million and a fair value of $10.3 million were reclassified to available for sale upon the adoption date. An unrealized loss of $75 thousand (net of taxes) was recognized in the accumulated other comprehensive income component of shareholders’ equity at the date of adoption. At December 31, 2019 and 2018 , securities with a fair value of $431.9 million and $439.7 million , respectively, were pledged as collateral for FHLB borrowings, potential borrowings with the FRB, certain public deposits and for other purposes. See Note 11 for additional discussion of FHLB borrowings. The schedule of maturities of available for sale debt securities is presented below. Mortgage-backed securities are included based on weighted average maturities, adjusted for anticipated prepayments. All other debt securities are included based on contractual maturities. Actual maturities may differ from amounts presented because certain issuers have the right to call or prepay obligations with or without call or prepayment penalties. (Dollars in thousands) December 31, 2019 Amortized Cost Fair Value Due in one year or less $103,241 $103,962 Due after one year to five years 349,290 351,538 Due after five years to ten years 264,354 264,958 Due after ten years 178,388 179,032 Total securities $895,273 $899,490 Included in the above table are available for sale debt securities with an amortized cost balance of $180.4 million and a fair value of $179.1 million at December 31, 2019 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 4 months to 17 years, with call features ranging from 1 month to 2 years. Other-Than-Temporary Impairment Assessment Management assesses whether the decline in fair value of investment securities is other-than-temporary on a regular basis. Unrealized losses on debt securities may occur from current market conditions, increases in interest rates since the time of purchase, a structural change in an investment, volatility of earnings of a specific issuer, or deterioration in credit quality of the issuer. Management evaluates impairments in value both qualitatively and quantitatively to assess whether they are other-than-temporary. The following tables summarize temporarily impaired securities, segregated by length of time the securities have been in a continuous unrealized loss position: (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2019 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises 3 $20,364 ($136 ) 3 $49,902 ($97 ) 6 $70,266 ($233 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 4 41,150 (56 ) 23 216,804 (2,908 ) 27 257,954 (2,964 ) Individual name issuer trust preferred debt securities — — — 5 12,579 (745 ) 5 12,579 (745 ) Corporate bonds — — — 3 10,183 (958 ) 3 10,183 (958 ) Total temporarily impaired securities 7 $61,514 ($192 ) 34 $289,468 ($4,708 ) 41 $350,982 ($4,900 ) (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2018 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises — $— $— 16 $157,032 ($4,467 ) 16 $157,032 ($4,467 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 10 47,060 (439 ) 51 438,701 (16,178 ) 61 485,761 (16,617 ) Individual name issuer trust preferred debt securities — — — 5 11,772 (1,535 ) 5 11,772 (1,535 ) Corporate bonds 3 1,198 (9 ) 5 10,427 (1,768 ) 8 11,625 (1,777 ) Total temporarily impaired securities 13 $48,258 ($448 ) 77 $617,932 ($23,948 ) 90 $666,190 ($24,396 ) Further deterioration in credit quality of the underlying issuers of the securities, deterioration in the condition of the financial services industry, worsening of the current economic environment, or additional declines in real estate values, among other things, may further affect the fair value of these securities and increase the potential that certain unrealized losses be designated as other-than-temporary in future periods, and the Corporation may incur write-downs. Obligations of U.S. Government Agency and U.S. Government-Sponsored Enterprise Securities, including Mortgage-Backed Securities The gross unrealized losses on U.S. government agency and U.S. government-sponsored debt securities, including mortgage-backed securities, were primarily attributable to relative changes in interest rates since the time of purchase. The contractual cash flows for these securities are guaranteed by U.S. government agencies and U.S. government-sponsored enterprises. Management believes that the unrealized losses on these debt security holdings are a function of changes in investment spreads and interest rate movements and not changes in credit quality. Management expects to recover the entire amortized cost basis of these securities. Furthermore, the Corporation does not intend to sell these securities and it is not more-likely-than-not that the Corporation will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at December 31, 2019 . Individual Name Issuer Trust Preferred Debt Securities Included in debt securities in an unrealized loss position at December 31, 2019 were five trust preferred securities issued by four individual companies in the banking sector. Management believes the unrealized losses on these holdings are primarily attributable to changes in the investment spreads and interest rates and not changes in the credit quality of the issuers of the debt securities. Based on the information available through the filing date of this report, all individual name issuer trust preferred debt securities held in our portfolio continue to accrue interest and make payments as expected with no payment deferrals or defaults on the part of the issuers. As of December 31, 2019 , individual name issuer trust preferred debt securities with an amortized cost of $2.0 million and unrealized losses of $161 thousand were rated below investment grade by Standard & Poors, Inc. Management reviewed the collectability of these securities taking into consideration such factors as the financial condition of the issuers, reported regulatory capital ratios of the issuers, credit ratings, including ratings in effect as of the reporting period date as well as credit rating changes between the reporting period date and the filing date of this report, and other information. We noted no additional downgrades to below investment grade between December 31, 2019 and the filing date of this report. Based on this review, management concluded that it expects to recover the entire amortized cost basis of these securities. Furthermore, the Corporation does not intend to sell these securities and it is not more-likely-than-not that the Corporation will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at December 31, 2019 . Corporate Bonds At December 31, 2019 , the Corporation had three corporate bond holdings with unrealized losses totaling $958 thousand . These investment grade corporate bonds were issued by large corporations in the financial services industry. Management believes the unrealized losses on these bonds are a function of the changes in the investment spreads and interest rate movements and not changes in the credit quality of the issuers of the debt securities. Management expects to recover the entire amortized cost basis of these securities. Furthermore, the Corporation does not intend to sell these securities and it is not more-likely-than-not that the Corporation will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at December 31, 2019 . The following table summarizes amounts relating to sales of securities: (Dollars in thousands) For the periods ended December 31, 2019 2018 2017 Proceeds from sales $11,877 $— $— Gross realized gains $— $— $— Gross realized losses (53 ) — — Net realized losses on securities ($53 ) $— $—

Loans

Loans	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Loans	Loans The following is a summary of loans: (Dollars in thousands) December 31, 2019 December 31, 2018 Amount % Amount % Commercial: Commercial real estate (1) $1,547,572 40 % $1,392,408 38 % Commercial & industrial (2) 585,289 15 620,704 17 Total commercial 2,132,861 55 2,013,112 55 Residential Real Estate: Residential real estate (3) 1,449,090 37 1,360,387 37 Consumer: Home equity 290,874 7 280,626 8 Other (4) 20,174 1 26,235 — Total consumer 311,048 8 306,861 8 Total loans (5) $3,892,999 100 % $3,680,360 100 % (1) Commercial real estate (“CRE”) consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings. (2) Commercial and industrial (“C&I”) consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (3) Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties. (4) Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 . As of December 31, 2019 and 2018 , loans amounting to $2.1 billion and $2.0 billion , respectively, were pledged as collateral to the FHLB under a blanket pledge agreement and to the FRB for the discount window. See Note 11 for additional disclosure regarding borrowings. Concentrations of Credit Risk A significant portion of our loan portfolio is concentrated among borrowers in southern New England and a substantial portion of the portfolio is collateralized by real estate in this area. The ability of single family residential and consumer borrowers to honor their repayment commitments is generally dependent on the level of overall economic activity within the market area and real estate values. The ability of commercial borrowers to honor their repayment commitments is dependent on the general economy as well as the health of the real estate economic sector in the Corporation’s market area. Past Due Loans Past due status is based on the contractual payment terms of the loan. The following tables present an aging analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due December 31, 2019 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $830 $— $603 $1,433 $1,546,139 $1,547,572 Commercial & industrial 1 — — 1 585,288 585,289 Total commercial 831 — 603 1,434 2,131,427 2,132,861 Residential Real Estate: Residential real estate 4,574 2,155 4,700 11,429 1,437,661 1,449,090 Consumer: Home equity 971 729 996 2,696 288,178 290,874 Other 42 — 88 130 20,044 20,174 Total consumer 1,013 729 1,084 2,826 308,222 311,048 Total loans $6,418 $2,884 $6,387 $15,689 $3,877,310 $3,892,999 (Dollars in thousands) Days Past Due December 31, 2018 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $155 $925 $— $1,080 $1,391,328 $1,392,408 Commercial & industrial — — — — 620,704 620,704 Total commercial 155 925 — 1,080 2,012,032 2,013,112 Residential Real Estate: Residential real estate 6,318 2,693 1,509 10,520 1,349,867 1,360,387 Consumer: Home equity 1,281 156 552 1,989 278,637 280,626 Other 33 — — 33 26,202 26,235 Total consumer 1,314 156 552 2,022 304,839 306,861 Total loans $7,787 $3,774 $2,061 $13,622 $3,666,738 $3,680,360 Included in past due loans as of December 31, 2019 and 2018 , were nonaccrual loans of $11.5 million and $8.6 million , respectively. All loans 90 days or more past due at December 31, 2019 and 2018 were classified as nonaccrual. Impaired Loans A loan is considered impaired when, based on current information and events, it is probable that the Corporation will not be able to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Impaired loans include nonaccrual loans and loans restructured in a troubled debt restructuring. The Corporation identifies loss allocations for impaired loans on an individual loan basis. The following is a summary of impaired loans: (Dollars in thousands) Recorded Investment (1) Unpaid Principal Related Allowance December 31, 2019 2018 2019 2018 2019 2018 No Related Allowance Recorded Commercial: Commercial real estate $— $925 $— $926 $— $— Commercial & industrial — 4,681 — 4,732 — — Total commercial — 5,606 — 5,658 — — Residential Real Estate: Residential real estate 13,968 9,347 14,803 9,695 — — Consumer: Home equity 1,471 1,360 1,472 1,360 — — Other 88 — 88 — — — Total consumer 1,559 1,360 1,560 1,360 — — Subtotal 15,527 16,313 16,363 16,713 — — With Related Allowance Recorded Commercial: Commercial real estate 603 — 926 — — — Commercial & industrial 657 52 657 73 580 — Total commercial 1,260 52 1,583 73 580 — Residential Real Estate: Residential real estate 687 364 714 390 95 100 Consumer: Home equity 292 85 291 85 291 24 Other 18 22 18 22 2 3 Total consumer 310 107 309 107 293 27 Subtotal 2,257 523 2,606 570 968 127 Total impaired loans $17,784 $16,836 $18,969 $17,283 $968 $127 Total: Commercial $1,260 $5,658 $1,583 $5,731 $580 $— Residential real estate 14,655 9,711 15,517 10,085 95 100 Consumer 1,869 1,467 1,869 1,467 293 27 Total impaired loans $17,784 $16,836 $18,969 $17,283 $968 $127 (1) The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest. The following table presents the average recorded investment balance of impaired loans and interest income recognized on impaired loans segregated by loan class: (Dollars in thousands) Average Recorded Investment Interest Income Recognized Years ended December 31, 2019 2018 2017 2019 2018 2017 Commercial: Commercial real estate $864 $1,050 $8,425 $1 $— $79 Commercial & industrial 2,149 5,403 6,445 106 259 281 Total commercial 3,013 6,453 14,870 107 259 360 Residential real estate: Residential real estate 11,575 9,645 14,571 473 393 444 Consumer: Home equity 1,466 1,182 685 58 52 31 Other 68 69 143 2 5 10 Total consumer 1,534 1,251 828 60 57 41 Totals $16,122 $17,349 $30,269 $640 $709 $845 Nonaccrual Loans The following is a summary of nonaccrual loans, segregated by class of loans: (Dollars in thousands) December 31, 2019 2018 Commercial: Commercial real estate $603 $925 Commercial & industrial 657 — Total commercial 1,260 925 Residential Real Estate: Residential real estate 14,297 9,346 Consumer: Home equity 1,763 1,436 Other 88 — Total consumer 1,851 1,436 Total nonaccrual loans $17,408 $11,707 Accruing loans 90 days or more past due $— $— As of December 31, 2019 and 2018 , loans secured by one- to four-family residential property amounting to $5.8 million and $761 thousand , respectively, were in process of foreclosure. Nonaccrual loans of $5.9 million and $3.1 million , respectively, were current as to the payment of principal and interest as of December 31, 2019 and 2018 . There were no significant commitments to lend additional funds to borrowers whose loans were on nonaccrual status at December 31, 2019 . Troubled Debt Restructurings The recorded investment in troubled debt restructurings consists of unpaid principal balance, net of charge-offs and unamortized deferred loan origination fees and costs, at the time of the restructuring. For accruing troubled debt restructured loans, the recorded investment also includes accrued interest. The recorded investment in troubled debt restructurings was $869 thousand and $5.6 million , respectively, at December 31, 2019 and 2018 . The allowance for loan losses included specific reserves for these troubled debt restructurings of $97 thousand and $103 thousand , respectively, at December 31, 2019 and 2018 . In 2019 , there were no loans modified as a troubled debt restructuring. In 2018 , there was one commercial and industrial loan modified as a troubled debt restructuring with a pre-modification and post-modification recorded investment of $608 thousand . This troubled debt restructuring included a combination of concessions pertaining to maturity and interest only payment terms. In 2019 , there were no payment defaults on troubled debt restructured loans modified within the previous 12 months. In 2018 , payment defaults on troubled debt restructured loans modified within the previous 12 months occurred on one loan with a carrying value of $608 thousand at the time of default. As of December 31, 2019 , there were no significant commitments to lend additional funds to borrowers whose loans were restructured. Credit Quality Indicators Commercial The Corporation utilizes an internal rating system to assign a risk to each of its commercial loans. Loans are rated on a scale of 1 to 10. This scale can be assigned to three broad categories including “pass” for ratings 1 through 6, “special mention” for 7-rated loans, and “classified” for loans rated 8, 9 or 10. The loan rating system takes into consideration parameters including the borrower’s financial condition, the borrower’s performance with respect to loan terms, the adequacy of collateral, the adequacy of guarantees and other credit quality characteristics. For non-impaired loans, the Corporation takes the risk rating into consideration along with other credit attributes in the establishment of an appropriate allowance for loan losses. See Note 6 for additional information. A description of the commercial loan categories is as follows: Pass - Loans with acceptable credit quality, defined as ranging from superior or very strong to a status of lesser stature. Superior or very strong credit quality is characterized by a high degree of cash collateralization or strong balance sheet liquidity. Lesser stature loans have an acceptable level of credit quality but exhibit some weakness in various credit metrics such as collateral adequacy, cash flow, secondary sources of repayment, or performance inconsistency or may be in an industry or of a loan type known to have a higher degree of risk. Special Mention - Loans with potential weaknesses that deserve management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the asset or in the Bank’s position as creditor at some future date. Special Mention assets are not adversely classified and do not expose the Bank to sufficient risk to warrant adverse classification. Examples of these conditions include but are not limited to outdated or poor quality financial data, strains on liquidity and leverage, losses or negative trends in operating results, marginal cash flow, weaknesses in occupancy rates or trends in the case of commercial real estate and frequent delinquencies. Classified - Loans identified as “substandard,” “doubtful” or “loss” based on criteria consistent with guidelines provided by banking regulators. A “substandard” loan has defined weaknesses which make payment default or principal exposure likely, but not yet certain. Such loans are apt to be dependent upon collateral liquidation, a secondary source of repayment or an event outside of the normal course of business. The loans are closely watched and are either already on nonaccrual status or may be placed on nonaccrual status when management determines there is uncertainty of collectability. A “doubtful” loan is placed on nonaccrual status and has a high probability of loss, but the extent of the loss is difficult to quantify due to dependency upon collateral having a value that is difficult to determine or upon some near-term event which lacks certainty. A loan in the “loss” category is considered generally uncollectible or the timing or amount of payments cannot be determined. “Loss” is not intended to imply that the loan has no recovery value, but rather, it is not practical or desirable to continue to carry the asset. The Corporation’s procedures call for loan ratings and classifications to be revised whenever information becomes available that indicates a change is warranted. On a quarterly basis, management reviews the criticized loan portfolio, which generally consists of commercial loans that are risk-rated special mention or worse, and other selected loans. Management’s review focuses on the current status of the loans and strategies to improve the credit. An annual loan review program is conducted by a third party to provide an independent evaluation of the creditworthiness of the commercial loan portfolio, the quality of the underwriting and credit risk management practices and the appropriateness of the risk rating classifications. This review is supplemented with selected targeted internal reviews of the commercial loan portfolio. The following table presents the commercial loan portfolio, segregated by category of credit quality indicator: (Dollars in thousands) Pass Special Mention Classified December 31, 2019 2018 2019 2018 2019 2018 Commercial: Commercial real estate $1,546,139 $1,387,666 $830 $205 $603 $4,537 Commercial & industrial 549,416 559,019 24,961 50,426 10,912 11,259 Total commercial $2,095,555 $1,946,685 $25,791 $50,631 $11,515 $15,796 Residential and Consumer Management monitors the relatively homogeneous residential real estate and consumer loan portfolios on an ongoing basis using delinquency information by loan type. For non-impaired residential real estate and consumer loans, the Corporation assigns loss allocation factors to each respective loan type. Other techniques are utilized to monitor indicators of credit deterioration in the residential real estate loans and consumer loan portfolios. Among these techniques is the periodic tracking of loans with an updated Fair Isaac Corporation (“FICO”) score and an estimated loan to value (“LTV”) ratio. LTV ratio is determined via statistical modeling analyses. The indicated LTV levels are estimated based on such factors as the location, the original LTV ratio, and the date of origination of the loan and do not reflect actual appraisal amounts. The results of these analyses and other loan review procedures, including selected targeted internal reviews, are taken into consideration in the determination of loss allocation factors for residential real estate and home equity consumer credits. The following table presents the residential and consumer loan portfolios, segregated by category of credit quality indicator: (Dollars in thousands) Current Past Due December 31, 2019 2018 2019 2018 Residential Real Estate: Residential real estate $1,437,661 $1,349,867 $11,429 $10,520 Consumer: Home equity $288,178 $278,637 $2,696 $1,989 Other 20,044 26,202 130 33 Total consumer $308,222 $304,839 $2,826 $2,022 Loan Servicing Activities Loans sold with servicing retained result in the capitalization of loan servicing rights. The following table presents an analysis of loan servicing rights: (Dollars in thousands) Loan Servicing Rights Valuation Allowance Total Balance at December 31, 2016 $3,493 $— $3,493 Loan servicing rights capitalized 1,104 — 1,104 Amortization (984 ) — (984 ) Balance at December 31, 2017 3,613 — 3,613 Loan servicing rights capitalized 905 — 905 Amortization (867 ) — (867 ) Balance at December 31, 2018 3,651 — 3,651 Loan servicing rights capitalized 902 — 902 Amortization (1,027 ) — (1,027 ) Balance at December 31, 2019 $3,526 $— $3,526 The following table presents estimated aggregate amortization expense related to loan servicing assets: (Dollars in thousands) Years ending December 31: 2020 $825 2021 632 2022 484 2023 371 2024 284 2025 and thereafter 930 Total estimated amortization expense $3,526 Loans sold to others are serviced by the Corporation on a fee basis under various agreements. Loans serviced for others are not included in the Consolidated Balance Sheets. The following table presents the balance of loans serviced for others by type of loan: (Dollars in thousands) December 31, 2019 2018 Residential mortgages $586,996 $588,534 Commercial loans 159,948 142,218 Total $746,944 $730,752

Allowance for Loan Losses

Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Allowance for Loan Losses	Allowance for Loan Losses The allowance for loan losses is management’s best estimate of incurred losses inherent in the loan portfolio as of the balance sheet date. The Corporation uses a methodology to systematically measure the amount of estimated loan loss exposure inherent in the loan portfolio for purposes of establishing a sufficient allowance for loan losses. The methodology includes: (1) the identification of loss allocations for individual loans deemed to be impaired and (2) the application of loss allocation factors for non-impaired loans based on historical loss experience and estimated loss emergence period, with adjustments for various exposures that management believes are not adequately represented by historical loss experience. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2019 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $15,381 $5,847 $21,228 $3,987 $1,603 $254 $1,857 $27,072 Charge-offs (1,028 ) (21 ) (1,049 ) (486 ) (390 ) (95 ) (485 ) (2,020 ) Recoveries 125 168 293 — 72 22 94 387 Provision 263 (2,073 ) (1,810 ) 3,114 105 166 271 1,575 Ending Balance $14,741 $3,921 $18,662 $6,615 $1,390 $347 $1,737 $27,014 The following table presents the activity in the allowance for loan losses for the year ended December 31, 2018 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $12,729 $5,580 $18,309 $5,427 $2,412 $340 $2,752 $26,488 Charge-offs (627 ) (10 ) (637 ) (250 ) (193 ) (107 ) (300 ) (1,187 ) Recoveries 25 119 144 21 29 27 56 221 Provision 3,254 158 3,412 (1,211 ) (645 ) (6 ) (651 ) 1,550 Ending Balance $15,381 $5,847 $21,228 $3,987 $1,603 $254 $1,857 $27,072 The following table presents the activity in the allowance for loan losses for the year ended December 31, 2017 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $11,166 $6,992 $18,158 $5,252 $1,889 $705 $2,594 $26,004 Charge-offs (1,867 ) (336 ) (2,203 ) (74 ) (79 ) (106 ) (185 ) (2,462 ) Recoveries 82 169 251 39 33 23 56 346 Provision 3,348 (1,245 ) 2,103 210 569 (282 ) 287 2,600 Ending Balance $12,729 $5,580 $18,309 $5,427 $2,412 $340 $2,752 $26,488 The following table presents the Corporation’s loan portfolio and associated allowance for loan losses by portfolio segment and by impairment methodology: (Dollars in thousands) December 31, 2019 December 31, 2018 Related Allowance Related Allowance Loans Loans Loans Individually Evaluated For Impairment Commercial: Commercial real estate $603 $— $925 $— Commercial & industrial 657 580 4,714 — Total commercial 1,260 580 5,639 — Residential Real Estate: Residential real estate 14,654 95 9,710 100 Consumer: Home equity 1,763 291 1,445 24 Other 106 2 22 3 Total consumer 1,869 293 1,467 27 Subtotal 17,783 968 16,816 127 Loans Collectively Evaluated For Impairment Commercial: Commercial real estate 1,546,969 14,741 1,391,483 15,381 Commercial & industrial 584,632 3,341 615,990 5,847 Total commercial 2,131,601 18,082 2,007,473 21,228 Residential Real Estate: Residential real estate 1,434,436 6,520 1,350,677 3,887 Consumer: Home equity 289,111 1,099 279,182 1,579 Other 20,068 345 26,212 251 Total consumer 309,179 1,444 305,394 1,830 Subtotal 3,875,216 26,046 3,663,544 26,945 Total $3,892,999 $27,014 $3,680,360 $27,072

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment The following presents a summary of premises and equipment: (Dollars in thousands) December 31, 2019 2018 Land $5,921 $6,020 Premises and improvements 40,982 40,210 Furniture, fixtures and equipment 24,760 24,798 Total premises and equipment 71,663 71,028 Less accumulated depreciation 42,963 42,023 Total premises and equipment, net $28,700 $29,005 Depreciation of premises and equipment amounted to $3.3 million , $3.3 million and $3.5 million , respectively, for the years ended December 31, 2019 , 2018 , and 2017 .

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles	Goodwill and Intangible Assets The following table presents the carrying value of goodwill at the reporting unit (or business segment) level: (Dollars in thousands) December 31, 2019 2018 Commercial Banking Segment $22,591 $22,591 Wealth Management Services Segment 41,318 41,318 Balance at December 31, 2018 $63,909 $63,909 The balance of goodwill in the Commercial Banking segment arose from the acquisition of First Financial Corp. in 2002. The balance of goodwill in the Wealth Management Services segment arose from the 2005 acquisition of Weston Financial and the 2015 acquisition of Halsey. The following table presents the components of intangible assets: (Dollars in thousands) December 31, 2019 2018 Gross carrying amount $20,803 $20,803 Accumulated amortization 13,585 12,641 Net amount $7,218 $8,162 The balance of intangible assets at December 31, 2019 includes wealth management advisory contracts resulting from the 2005 acquisition of Weston Financial and the 2015 acquisition of Halsey. The wealth management advisory contracts resulting from the Weston Financial acquisition are being amortized over a 20 -year life using a declining balance method, based on expected attrition for the current customer base derived from historical runoff data. The wealth management advisory contracts resulting from the acquisition of Halsey are being amortized on a straight-line basis over a 15 -year life. Amortization expense for the years ended December 31, 2019 , 2018 , and 2017 , amounted to $943 thousand , $979 thousand and $1.0 million , respectively. The following table presents estimated annual amortization expense for intangible assets at December 31, 2019 : (Dollars in thousands) Years ending December 31, 2020 $914 2021 890 2022 860 2023 843 2024 826 2025 and thereafter 2,885

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The following table presents the components of income tax expense: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Current tax expense: Federal $17,298 $15,460 $23,827 State 3,254 2,863 2,201 Total current tax expense 20,552 18,323 26,028 Deferred tax (benefit) expense: Federal (1,294 ) 63 5,717 State (197 ) (126 ) (30 ) Total deferred (benefit) tax expense (1,491 ) (63 ) 5,687 Total income tax expense $19,061 $18,260 $31,715 Total income tax expense varies from the amount determined by applying the Federal income tax rate to income before income taxes. The following table presents the reasons for the differences: Years ended December 31, 2019 2018 2017 (Dollars in thousands) Amount Rate Amount Rate Amount Rate Tax expense at Federal statutory rate $18,518 21.0 % $18,205 21.0 % $27,174 35.0 % (Decrease) increase in taxes resulting from: Tax-exempt income, net (814 ) (0.9 ) (809 ) (0.9 ) (1,313 ) (1.7 ) Dividends received deduction (36 ) — (45 ) (0.1 ) (55 ) (0.1 ) BOLI (494 ) (0.6 ) (461 ) (0.5 ) (757 ) (0.9 ) Share-based compensation (221 ) (0.3 ) (444 ) (0.5 ) (481 ) (0.6 ) Federal tax credits (364 ) (0.4 ) (364 ) (0.4 ) (364 ) (0.5 ) Change in fair value of contingent consideration — — (39 ) (0.1 ) (225 ) (0.3 ) State income tax expense, net of federal tax benefit 2,417 2.7 2,162 2.5 1,411 1.8 Adjustment to net deferred tax assets for enacted changes in federal tax law — — — — 6,170 7.9 Other 55 0.1 55 0.1 155 0.2 Total income tax expense $19,061 21.6 % $18,260 21.1 % $31,715 40.8 % The Tax Act was signed into law in 2017. The enactment of the Tax Act required companies to revalue deferred tax assets and liabilities in light of the new federal income tax rate. As a result, in 2017 the Corporation’s net deferred tax assets were written down by $6.2 million , with a corresponding increase to income tax expense. The majority of the provisions of the Tax Act became effective on January 1, 2018. The provisions that impacted the Corporation included the reduction of the corporate income tax rate from 35% to 21%, changes to the deductibility of certain meals and entertainment expenses, and changes to the deductibility of executive compensation. The Tax Act also accelerated expensing of certain depreciable property for assets placed in service after September 27, 2017 and before January 1, 2023. The following table presents the approximate tax effects of temporary differences that give rise to deferred tax assets and deferred tax liabilities: (Dollars in thousands) December 31, 2019 2018 Deferred tax assets: Allowance for loan losses $6,348 $6,362 Operating lease liabilities 6,782 — Defined benefit pension obligations 1,361 420 Deferred compensation 4,200 3,688 Deferred loan origination fees 1,505 1,410 Share-based compensation 1,358 1,124 Net unrealized losses on available for sale debt securities — 5,149 Other 2,031 1,917 Deferred tax assets 23,585 20,070 Deferred tax liabilities: Net unrealized gains on available for sale debt securities (991 ) — Amortization of intangibles (1,696 ) (1,918 ) Operating lease right-of-use assets (6,296 ) — Deferred loan origination costs (4,084 ) (3,897 ) Loan servicing rights (829 ) (858 ) Other (1,388 ) (1,120 ) Deferred tax liabilities (15,284 ) (7,793 ) Net deferred tax asset $8,301 $12,277 Effective January 1, 2019 the Corporation adopted ASC 842. As a result, the Corporation recognized a deferred tax asset related to operating lease liabilities and a corresponding deferred tax liability related to operating lease right-of-use assets. Prior to adoption, the tax effect of the temporary difference related to operating lease rent expense was presented net within other deferred tax assets. The Corporation’s net deferred tax asset is included in other assets in the Consolidated Balance Sheets. Management has determined that a valuation allowance is not required for any of the deferred tax assets since it is more-likely-than-not that these assets will be realized primarily through future reversals of existing taxable temporary differences or by offsetting projected future taxable income. The Corporation had no unrecognized tax benefits as of December 31, 2019 and 2018 . The Corporation files income tax returns in the U.S. federal jurisdiction and various state jurisdictions. Generally, the Corporation is no longer subject to U.S. federal income and state tax examinations by tax authorities for years before 2016 .

Deposits

Deposits	12 Months Ended
	Dec. 31, 2019
Deposits [Abstract]
Deposits	Deposits The following table presents a summary of deposits: (Dollars in thousands) December 31, 2019 2018 Noninterest-bearing demand deposits $609,924 $603,216 Interest-bearing demand deposits 159,938 178,733 NOW accounts 520,295 466,568 Money market accounts 765,899 646,878 Savings accounts 373,503 373,545 Time deposits (1) 1,069,323 1,255,108 Total deposits $3,498,882 $3,524,048 (1) Includes wholesale brokered time deposits. The following table presents scheduled maturities of time certificates of deposit: (Dollars in thousands) Scheduled Maturity Weighted Average Rate Years ending December 31: 2020 $751,525 1.95 % 2021 161,034 2.27 2022 105,846 2.42 2023 32,462 2.04 2024 18,326 1.58 2025 and thereafter 130 2.26 Balance at December 31, 2019 $1,069,323 2.04 % The following table presents the amount of time certificates of deposit in denominations of $100 thousand or more at December 31, 2019 , maturing during the periods indicated: (Dollars in thousands) January 1, 2020 to March 31, 2020 $57,864 April 1, 2020 to June 30, 2020 106,574 July 1, 2020 to December 31, 2020 115,505 January 1, 2021 and beyond 175,831 Balance at December 31, 2019 $455,774 Time certificates of deposit in denominations of $250 thousand or more totaled $147.3 million and $129.3 million , respectively, at December 31, 2019 and 2018 .

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Borrowings	Borrowings Federal Home Loan Bank Advances Advances payable to FHLB amounted to $1.1 billion and $950.7 million , respectively, at December 31, 2019 and 2018 . As of December 31, 2019 and 2018 , the Bank had access to a $40.0 million unused line of credit with the FHLB and also had remaining available borrowing capacity of $535.0 million and $628.5 million , respectively. The Bank pledges certain qualified investment securities and loans as collateral to the FHLB. The following table presents maturities and weighted average interest rates on FHLB advances outstanding as of December 31, 2019 : (Dollars in thousands) Scheduled Weighted 2020 $974,033 2.07 % 2021 77,222 2.52 2022 813 5.12 2023 5,238 3.80 2024 40,900 2.51 2025 and thereafter 43,258 3.29 Total $1,141,464 2.17 % Advances payable to FHLB include short-term advances with original maturity due dates of one year or less. The following table presents certain information concerning short-term FHLB advances: (Dollars in thousands) As of and for the years ended December 31, 2019 2018 2017 Average amount outstanding during the period $718,722 $484,090 $351,692 Amount outstanding at end of period 897,000 630,000 367,500 Highest month end balance during period 897,000 630,000 417,500 Weighted-average interest rate at end of period 2.06 % 2.67 % 1.57 % Weighted-average interest rate during the period 2.59 2.23 1.20 Junior Subordinated Debentures Junior subordinated debentures amounted to $22.7 million at December 31, 2019 and 2018 . The Bancorp sponsored the creation of WT Capital Trust I (“Trust I”) and WT Capital Trust II (“Trust II”), Delaware statutory trusts created for the sole purpose of issuing trust preferred securities and investing the proceeds in junior subordinated debentures of the Bancorp. The Bancorp is the owner of all of the common securities of the trusts. In accordance with GAAP, the trusts are treated as unconsolidated subsidiaries. On August 29, 2005, Trust I issued $8.3 million of capital securities (“Trust I Capital Securities”) in a private placement of trust preferred securities. The Trust I Capital Securities mature in September 2035, are redeemable at the Bancorp’s option and require quarterly distributions by Trust I to the holder of the Trust I Capital Securities equal to the three-month LIBOR rate plus 1.45% . The Bancorp has guaranteed the Trust I Capital Securities and, to the extent not paid by Trust I, accrued and unpaid distributions on the Trust I Capital Securities, as well as the redemption price payable to the Trust I Capital Securities holders. The proceeds of the Trust I Capital Securities, along with proceeds from the issuance of common securities by Trust I to the Bancorp, were used to purchase $8.3 million of the Bancorp’s junior subordinated deferrable interest notes (the “Trust I Debentures”) and constitute the primary asset of Trust I. Like the Trust I Capital Securities, the Trust I Debentures bear interest at a rate equal to the three-month LIBOR rate plus 1.45% . The Trust I Debentures mature on September 15, 2035, but may be redeemed at par at the Bancorp’s option, subject to the approval of the applicable banking regulator to the extent required under applicable guidelines or policies. On August 29, 2005, Trust II issued $14.4 million of capital securities (“Trust II Capital Securities”) in a private placement of trust preferred securities. The Trust II Capital Securities mature in November 2035, are redeemable at the Bancorp’s option and require quarterly distributions by Trust II to the holder of the Trust II Capital Securities, at a rate equal to the three-month LIBOR rate plus 1.45% . The Bancorp has guaranteed the Trust II Capital Securities and, to the extent not paid by Trust II, accrued and unpaid distributions on the Trust II Capital Securities, as well as the redemption price payable to the Trust II Capital Securities holders. The proceeds of the Trust II Capital Securities, along with proceeds from the issuance of common securities by Trust II to the Bancorp, were used to purchase $14.4 million of the Bancorp’s junior subordinated deferrable interest notes (the “Trust II Debentures”) and constitute the primary asset of Trust II. Like the Trust II Capital Securities, the Trust II Debentures bear interest at a rate equal to the three-month LIBOR rate plus 1.45% . The Trust II Debentures mature on November 23, 2035, but may be redeemed at par at the Bancorp’s option, subject to the approval of the applicable banking regulator to the extent required under applicable guidelines or policies.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Shareholders' Equity	Shareholders' Equity 2019 Stock Repurchase Program On December 2, 2019, the Bancorp’s Board of Directors adopted a new Stock Repurchase Program. The Stock Repurchase Program, which replaces the Corporation’s 2006 stock repurchase plan, authorizes the repurchase of up to 850,000 shares, or approximately 5% , of the Corporation’s outstanding common stock. This authority may be exercised from time to time and in such amounts as market conditions warrant, and subject to regulatory considerations. The timing and actual number of shares repurchased will depend on a variety of factors including price, corporate and regulatory requirements, market conditions, and other corporate liquidity requirements and priorities. The Stock Repurchase Program expires on October 31, 2020 and may be modified, suspended, or discontinued at any time. As of December 31, 2019 , no shares have been repurchased under the 2019 Stock Repurchase Program. Dividends The primary source of liquidity for the Bancorp is dividends received from the Bank. The Bancorp and the Bank are regulated enterprises and their abilities to pay dividends are subject to regulatory review and restriction. Certain regulatory and statutory restrictions exist regarding dividends, loans, and advances from the Bank to the Bancorp. Generally, the Bank has the ability to pay dividends to the Bancorp subject to minimum regulatory capital requirements. The FDIC and the FRB have the authority to use their enforcement powers to prohibit a bank or bank holding company, respectively, from paying dividends if, in their opinion, the payment of dividends would constitute an unsafe or unsound practice. Under the most restrictive of these requirements, the Bank could have declared aggregate additional dividends of $257.1 million as of December 31, 2019 . Reserved Shares As of December 31, 2019 , a total of 1,696,991 common stock shares were reserved for issuance under the 2003 Stock Incentive Plan and the 2013 Stock Option and Incentive Plan. Regulatory Capital Requirements The Bancorp and the Bank are subject to various regulatory capital requirements administered by the FRB and the FDIC, respectively. Regulatory authorities can initiate certain mandatory actions if Bancorp or the Bank fail to meet minimum capital requirements, which could have a direct material effect on the Corporation’s financial statements. 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. These quantitative measures, to ensure capital adequacy, require minimum amounts and ratios. Capital levels at December 31, 2019 exceeded the regulatory minimum levels to be considered “well capitalized.” The following table presents the Corporation’s and the Bank’s actual capital amounts and ratios, as well as the corresponding minimum and well capitalized regulatory amounts and ratios that were in effect during the respective periods: (Dollars in thousands) Actual For Capital Adequacy Purposes To Be “Well Capitalized” Under Prompt Corrective Action Regulations Amount Ratio Amount Ratio Amount Ratio December 31, 2019 Total Capital (to Risk-Weighted Assets): Corporation $494,603 12.94 % $305,728 8.00 % N/A N/A Bank 490,993 12.85 305,693 8.00 $382,116 10.00 % Tier 1 Capital (to Risk-Weighted Assets): Corporation 467,296 12.23 229,296 6.00 N/A N/A Bank 463,686 12.13 229,270 6.00 305,693 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 445,298 11.65 171,972 4.50 N/A N/A Bank 463,686 12.13 171,952 4.50 248,375 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 467,296 9.04 206,682 4.00 N/A N/A Bank 463,686 8.98 206,596 4.00 258,245 5.00 December 31, 2018 Total Capital (to Risk-Weighted Assets): Corporation 455,699 12.56 290,146 8.00 N/A N/A Bank 453,033 12.49 290,128 8.00 362,660 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 428,338 11.81 217,609 6.00 N/A N/A Bank 425,672 11.74 217,596 6.00 290,128 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 406,340 11.20 163,207 4.50 N/A N/A Bank 425,672 11.74 163,197 4.50 235,729 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 428,338 8.89 192,690 4.00 N/A N/A Bank 425,672 8.84 192,652 4.00 240,815 5.00 (1) Leverage ratio. In addition to the minimum regulatory capital required for capital adequacy purposes outlined in the table above, the Corporation is required to maintain a minimum capital conservation buffer, in the form of common equity, in order to avoid restrictions on capital distributions and discretionary bonuses. The required amount of the capital conservation buffer was 1.875% on January 1, 2018. The capital conservation buffer increased another 0.625% on January 1, 2019, reaching the full requirement of 2.50%. The Corporation’s capital levels exceeded the minimum regulatory capital requirement plus the capital conversation buffer as of December 31, 2019 . The Bancorp owns the common stock of two capital trusts, which have issued trust preferred securities. In accordance with GAAP, the capital trusts are treated as unconsolidated subsidiaries. At both December 31, 2019 and 2018 , $22.0 million in trust preferred securities were included in the Tier 1 Capital of the Corporation for regulatory capital reporting purposes pursuant to the Federal Reserve’s capital adequacy guidelines.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Corporation’s derivative financial instruments are used to manage differences in the amount, timing and duration of the Corporation’s known or expected cash receipts and its known or expected cash payments principally to manage the Corporation’s interest rate risk. Additionally, the Corporation enters into interest rate derivatives to accommodate the business requirements of its customers. All derivatives are recognized as either assets or liabilities on the balance sheet and are measured at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative and resulting designation. Interest Rate Risk Management Agreements Interest rate risk management agreements, such as caps, swaps, and floors, are used from time to time as part of the Corporation’s interest rate risk management strategy. Interest rate swaps are agreements in which the Corporation and another party agree to exchange interest payments (e.g., fixed-rate for variable-rate payments) computed on a notional principal amount. Interest rate caps and floors represent options purchased by the Corporation to manage the interest rate paid throughout the term of the option contract. The credit risk associated with these transactions is the risk of default by the counterparty. To minimize this risk, the Corporation enters into interest rate agreements only with highly rated counterparties that management believes to be creditworthy. The notional amounts of these agreements do not represent amounts exchanged by the parties and, thus, are not a measure of the potential loss exposure. Cash Flow Hedging Instruments As of December 31, 2019 and 2018 , the Bancorp had two interest rate caps with a total notional amount of $22.7 million that were designated as cash flow hedges to hedge the interest rate risk associated with our variable rate junior subordinated debentures. For both interest rate caps, the Bancorp obtained the right to receive the difference between 3-month LIBOR and a 4.5% strike. The caps mature in 2020. As of December 31, 2019 and 2018 , the Bank had two interest rate swap contracts with a total notional amount of $60.0 million that were designated as cash flow hedges to hedge the interest rate risk associated with short-term variable rate FHLB advances. The interest rate swaps mature in 2021 and 2023. As of December 31, 2019 and 2018 , the Bank had three interest rate floor contracts with a total notional amount of $300.0 million that were designated as cash flow hedges to hedge the interest rate risk associated with a pool of variable rate commercial loans. The Bank obtained the right to receive the difference between 1-month LIBOR and a 1.0% strike for each of the interest rate floors. The floors mature in 2020. The changes in fair value of derivatives designated as cash flow hedges are recorded in other comprehensive income and subsequently reclassified to earnings when gains or losses are realized. Loan Related Derivative Contracts Interest Rate Swap Contracts with Customers The Corporation has entered into interest rate swap contracts to help commercial loan borrowers manage their interest rate risk. The interest rate swap contracts with commercial loan borrowers allow them to convert variable-rate loan payments to fixed-rate loan payments. When we enter into an interest rate swap contract with a commercial loan borrower, we simultaneously enter into a “mirror” swap contract with a third party. The third party exchanges the client’s fixed-rate loan payments for variable-rate loan payments. We retain the risk that is associated with the potential failure of counterparties and the risk inherent in originating loans. As of December 31, 2019 and 2018 , Washington Trust had interest rate swap contracts with commercial loan borrowers with notional amounts of $813.5 million and $648.0 million , respectively, and equal amounts of “mirror” swap contracts with third-party financial institutions. These derivatives are not designated as hedges and therefore, changes in fair value are recognized in earnings. Risk Participation Agreements The Corporation has entered into risk participation agreements with other banks in commercial loan arrangements. Participating banks guarantee the performance on borrower-related interest rate swap contracts. These derivatives are not designated as hedges and therefore, changes in fair value are recognized in earnings. Under a risk participation-out agreement, a derivative asset, the Corporation participates out a portion of the credit risk associated with the interest rate swap position executed with the commercial borrower for a fee paid to the participating bank. Under a risk participation-in agreement, a derivative liability, the Corporation assumes, or participates in, a portion of the credit risk associated with the interest rate swap position with the commercial borrower for a fee received from the other bank. As of December 31, 2019 , the notional amounts of the risk participation-out agreements and risk participation-in agreements were $61.2 million and $72.9 million , respectively, compared to $57.3 million and $46.5 million , respectively, as of December 31, 2018 . Foreign Exchange Contracts Foreign exchange contracts represent contractual commitments to buy or sell a foreign currency on a future date at a specified price. As of December 31, 2019 , the Corporation did not have any foreign exchange contracts. As of December 31, 2018 , the notional amount of foreign exchange contracts was $2.8 million . The Corporation used foreign exchange contracts on a limited basis to reduce its exposure to fluctuations in currency exchange rates associated with a commercial loan denominated in a foreign currency. Foreign exchange contracts are not designated as hedges and therefore changes in fair value are recognized in earnings. The changes in fair value on the foreign exchange contracts substantially offset the foreign currency translation gains and losses on the related commercial loan. Mortgage Loan Commitments Interest rate lock commitments are extended to borrowers and relate to the origination of mortgage loans held for sale. To mitigate the interest rate risk and pricing risk associated with rate locks and mortgage loans held for sale, the Corporation enters into forward sale commitments. Forward sale commitments are contracts for delayed delivery or net settlement of the underlying instrument, such as a residential real estate mortgage loan, where the seller agrees to deliver on a specified future date, either a specified instrument at a specified price or yield or the net cash equivalent of an underlying instrument. Both interest rate lock commitments and forward sale commitments are derivative financial instruments, but do not meet criteria for hedge accounting and therefore, the changes in fair value of these commitments are reflected in earnings. As of December 31, 2019 , the notional amounts of interest rate lock commitments and forward sale commitments were $51.4 million and $94.8 million , respectively, compared to $30.8 million and $62.0 million , respectively, as of December 31, 2018 . The following table presents the fair values of derivative instruments in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet Location Dec 31, Dec 31, Balance Sheet Location Dec 31, Dec 31, Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps Other assets $— $20 Other liabilities $— $— Interest rate swaps Other assets — 903 Other liabilities 730 — Interest rate floors Other assets 3 37 Other liabilities — — Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Other assets 27,736 5,340 Other liabilities 358 7,719 Mirror swaps with counterparties Other assets 351 7,592 Other liabilities 27,819 5,392 Risk participation agreements Other assets 1 — Other liabilities 1 — Foreign exchange contracts Other assets — — Other liabilities — 7 Mortgage loan commitments: Interest rate lock commitments Other assets 1,097 806 Other liabilities — — Forward sale commitments Other assets 30 — Other liabilities 827 816 Gross amounts 29,218 14,698 29,735 13,934 Less amounts offset in Consolidated Balance Sheets (1) 354 10,732 354 10,732 Net amounts presented in Consolidated Balance Sheets 28,864 3,966 29,381 3,202 Less collateral pledged (2) — — 27,105 1,460 Net amounts $28,864 $3,966 $2,276 $1,742 (1) Interest rate risk management contracts and loan related derivative contracts with counterparties are subject to master netting arrangements. (2) Collateral pledged to derivative counterparties is in the form of cash. Washington Trust may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions. The following tables present the effect of derivative instruments in the Corporation’s Consolidated Statements of Changes in Shareholders’ Equity and Consolidated Statements of Income: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax Years ended December 31, 2019 2018 2017 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps $52 $30 ($64 ) Interest rate swaps (1,232 ) 515 358 Interest rate floors 196 74 (346 ) Total ($984 ) $619 ($52 ) (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivatives Years ended December 31, Statement of Income Location 2019 2018 2017 Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income $29,910 ($290 ) $2,243 Mirror swaps with counterparties Loan related derivative income (26,043 ) 2,709 1,198 Risk participation agreements Loan related derivative income 97 (27 ) (233 ) Foreign exchange contracts Loan related derivative income 28 69 6 Mortgage loan commitments: Interest rate lock commitments Mortgage banking revenues 290 (139 ) (100 ) Forward sale commitments Mortgage banking revenues (1,818 ) 997 (328 ) Total $2,464 $3,319 $2,786

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Corporation uses fair value measurements to record fair value adjustments on certain assets and liabilities and to determine fair value disclosures. Items recorded at fair value on a recurring basis include securities available for sale, mortgage loans held for sale and derivatives. Additionally, from time to time, we may be required to record at fair value other assets on a nonrecurring basis, such as collateral dependent impaired loans, property acquired through foreclosure or repossession and mortgage servicing rights. These nonrecurring fair value adjustments typically involve the application of lower of cost or market accounting or write-downs of individual assets. Fair value is a market-based measurement, not an entity-specific measurement. Fair value measurements are determined based on the assumptions the market participants would use in pricing the asset or liability. In addition, GAAP specifies a hierarchy of valuation techniques based on whether the types of valuation information (“inputs”) are observable or unobservable. Observable inputs reflect market data obtained from independent sources, while unobservable inputs reflect the Corporation’s market assumptions. These two types of inputs have created the following fair value hierarchy: • Level 1 – Quoted prices for identical assets or liabilities in active markets. • Level 2 – Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in inactive markets; and model-derived valuations in which all significant inputs and significant value drivers are observable in active markets. • Level 3 – Valuations derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable in the markets and which reflect the Corporation’s market assumptions. Fair Value Option Election GAAP allows for the irrevocable option to elect fair value accounting for the initial and subsequent measurement for certain financial assets and liabilities on a contract-by-contract basis. The Corporation has elected the fair value option for mortgage loans held for sale to better match changes in fair value of the loans with changes in the fair value of the forward sale commitment contracts used to economically hedge them. The following table presents a summary of mortgage loans held for sale accounted for under the fair value option: (Dollars in thousands) December 31, 2019 2018 Aggregate fair value $27,833 $20,996 Aggregate principal balance 27,168 20,498 Difference between fair value and principal balance $665 $498 Changes in fair value of mortgage loans held for sale accounted for under the fair value option election amounted to a decrease of $167 thousand in 2019 , compared to a decrease of $45 thousand for 2018 . These amounts were partially offset in earnings by the changes in fair value of forward sale commitments used to economically hedge them. The changes in fair value are reported as a component of mortgage banking revenues in the Consolidated Statements of Income. There were no mortgage loans held for sale 90 days or more past due as of December 31, 2019 and 2018 . Valuation Techniques Debt Securities Available for sale debt securities are recorded at fair value on a recurring basis. When available, the Corporation uses quoted market prices to determine the fair value of debt securities; such items are classified as Level 1. There were no Level 1 securities held at December 31, 2019 and 2018 . Level 2 debt securities are traded less frequently than exchange-traded instruments. The fair value of these securities is determined using matrix pricing with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. This category includes obligations of U.S. government-sponsored enterprises, including mortgage-backed securities, obligations of states and political subdivisions, individual name issuer trust preferred debt securities and corporate bonds. Debt securities not actively traded whose fair value is determined through the use of cash flows utilizing inputs that are unobservable are classified as Level 3. There were no Level 3 securities held at December 31, 2019 and 2018 . Mortgage Loans Held for Sale The fair value of mortgage loans held for sale is estimated based on current market prices for similar loans in the secondary market and therefore are classified as Level 2 assets. Collateral Dependent Impaired Loans The fair value of collateral dependent loans that are deemed to be impaired is determined based upon the fair value of the underlying collateral. Such collateral primarily consists of real estate and, to a lesser extent, other business assets. For collateral dependent loans for which repayment is dependent on the sale of the collateral, management adjusts the fair value for estimated costs to sell. For collateral dependent loans for which repayment is dependent on the operation of the collateral, such as accruing troubled debt restructured loans, estimated costs to sell are not incorporated into the measurement. Management may also adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values resulting from its knowledge of the property. Internal valuations are utilized to determine the fair value of other business assets. Collateral dependent impaired loans are categorized as Level 3. Property Acquired Through Foreclosure or Repossession Property acquired through foreclosure or repossession included in other assets in the Consolidated Balance Sheets is adjusted to fair value less costs to sell upon transfer out of loans through a charge to allowance for loan losses. Subsequently, it is carried at the lower of carrying value or fair value less costs to sell. Such subsequent valuation charges are charged through earnings. Fair value is generally based upon appraised values of the collateral. Management may adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of the property, and such property is categorized as Level 3. Derivatives Interest rate cap, swap and floor contracts are traded in over-the-counter markets where quoted market prices are not readily available. Fair value measurements are determined using independent pricing models that utilize primarily market observable inputs, such as swap rates of different maturities and LIBOR rates. The Corporation also evaluates the credit risk of its counterparties as well as that of the Corporation. Accordingly, factors such as the likelihood of default by the Corporation and its counterparties, its net exposures and remaining contractual life are considered in determining if any fair value adjustments related to credit risk are required. Counterparty exposure is evaluated by netting positions that are subject to master netting agreements, as well as considering the amount of collateral securing the position, if any. Although the Corporation has determined that the majority of the inputs used to value its interest rate swap, cap and floor contracts fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with interest rate contracts and risk participation agreements utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by the Corporation and its counterparties. However, as of December 31, 2019 and 2018 , the Corporation has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Corporation has classified its derivative valuations in their entirety as Level 2. Fair value measurements of forward loan commitments (interest rate lock commitments and forward sale commitments) are primarily based on current market prices for similar assets in the secondary market for mortgage loans and therefore are classified as Level 2 assets. The fair value of interest rate lock commitments is also dependent on the ultimate closing of the loans. Pull-through rates are based on the Corporation’s historical data and reflect the Corporation’s best estimate of the likelihood that a commitment will result in a closed loan. Although the pull-through rates are Level 3 inputs, the Corporation has assessed the significance of the impact of pull-through rates on the overall valuation of its interest rate lock commitments and has determined that they are not significant to the overall valuation. As a result, the Corporation has classified its interest rate lock commitments as Level 2. Contingent Consideration Liability A contingent consideration liability was recognized upon the completion of the Halsey Associates, Inc. acquisition on August 1, 2015 representing the estimated present value of future earn-outs to be paid based on the future revenue growth of the acquired business during the five-year period following the acquisition. As of December 31, 2019, earn-out periods associated with this contingent consideration liability have ended. The fair value measurement was based upon unobservable inputs; therefore, the contingent liability was classified within Level 3 of the fair value hierarchy. The unobservable inputs included probability estimates regarding the likelihood of achieving revenue growth targets and the discount rates utilized the discounted cash flow calculations applied to the estimated earn-outs to be paid. The contingent consideration liability was remeasured to fair value at each reporting period taking into consideration changes in those unobservable inputs. Changes in the fair value of the contingent consideration liability were included in noninterest expenses in the Consolidated Statements of Income. Items Recorded at Fair Value on a Recurring Basis The following tables present the balances of assets and liabilities reported at fair value on a recurring basis: (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2019 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $157,648 $— $157,648 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 719,080 — 719,080 — Individual name issuer trust preferred debt securities 12,579 — 12,579 — Corporate bonds 10,183 — 10,183 — Mortgage loans held for sale 27,833 — 27,833 — Derivative assets 28,864 — 28,864 — Total assets at fair value on a recurring basis $956,187 $— $956,187 $— Liabilities: Derivative liabilities $29,381 $— $29,381 $— Total liabilities at fair value on a recurring basis $29,381 $— $29,381 $— (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2018 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $242,683 $— $242,683 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 660,793 — 660,793 — Obligations of states and political subdivisions 937 — 937 — Individual name issuer trust preferred debt securities 11,772 — 11,772 — Corporate bonds 11,625 — 11,625 — Mortgage loans held for sale 20,996 — 20,996 — Derivative assets 3,966 — 3,966 — Total assets at fair value on a recurring basis $952,772 $— $952,772 $— Liabilities: Derivative liabilities $3,202 $— $3,202 $— Total liabilities at fair value on a recurring basis $3,202 $— $3,202 $— It is the Corporation’s policy to review and reflect transfers between Levels as of the financial statement reporting date. There were no transfers in and/or out of Level 1, 2 or 3 during the years ended December 31, 2019 and 2018 . The contingent consideration liability is a Level 3 liability remeasured at fair value on a recurring basis. The following table presents the change in the contingent consideration liability, which is included in other liabilities in the Consolidated Balance Sheets. (Dollars in thousands) Years ended December 31, 2019 2018 Beginning Balance $— $1,404 Change in fair value — (187 ) Payments — (1,217 ) Ending Balance $— $— Items Recorded at Fair Value on a Nonrecurring Basis The following table presents the carrying value of assets held at December 31, 2019 , which were written down to fair value during the year ended December 31, 2019 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $1,448 $— $— $1,448 Property acquired through foreclosure or repossession 1,109 — — 1,109 Total assets at fair value on a nonrecurring basis $2,557 $— $— $2,557 The allowance for loan losses on collateral dependent impaired loans amounted to $871 thousand at December 31, 2019 . In 2019 , a write-down valuation adjustment of $1.0 million on property acquired through foreclosure or repossession was recognized and included in other noninterest expenses in the Consolidated Statements of Income. The following table presents the carrying value of assets held at December 31, 2018 , which were written down to fair value during the year ended December 31, 2018 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $883 $— $— $883 Property acquired through foreclosure or repossession 2,142 — — 2,142 Total assets at fair value on a nonrecurring basis $3,025 $— $— $3,025 The allowance for loan losses on collateral dependent impaired loans amounted to $24 thousand at December 31, 2018 . In 2018 , a write-down valuation adjustment of $1.0 million on property acquired through foreclosure or repossession was recognized and included in other noninterest expenses in the Consolidated Statements of Income. The following tables present valuation techniques and unobservable inputs for assets measured at fair value on a nonrecurring basis for which the Corporation has utilized Level 3 inputs to determine fair value: (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2019 Collateral dependent impaired loans $1,448 Appraisals of collateral Discount for costs to sell 0% - 20% (5%) Appraisal adjustments (1) 0% - 100% (67%) Property acquired through foreclosure or repossession 1,109 Appraisals of collateral Discount for costs to sell 12% Appraisal adjustments (1) 22% (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property. (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2018 Collateral dependent impaired loans $883 Appraisals of collateral Discount for costs to sell 0% - 10% (10%) Appraisal adjustments (1) 0% - 100% (2%) Property acquired through foreclosure or repossession 2,142 Appraisals of collateral Discount for costs to sell 13% Appraisal adjustments (1) 12% - 28% (20%) (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property. Valuation of Financial Instruments The estimated fair values and related carrying amounts for financial instruments for which fair value is only disclosed are presented below as of the periods indicated. The tables exclude financial instruments for which the carrying value approximates fair value such as cash and cash equivalents, FHLB stock, accrued interest receivable, bank-owned life insurance, non-maturity deposits and accrued interest payable. (Dollars in thousands) Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2019 Financial Assets: Loans, net of allowance for loan losses $3,865,985 $3,869,192 $— $— $3,869,192 Financial Liabilities: Time deposits $1,069,323 $1,082,830 $— $1,082,830 $— FHLB advances 1,141,464 1,145,242 — 1,145,242 — Junior subordinated debentures 22,681 19,628 — 19,628 — (Dollars in thousands) Carrying Amount Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2018 Financial Assets: Held to maturity debt securities $10,415 $10,316 $— $10,316 $— Loans, net of allowance for loan losses 3,653,288 3,598,025 — — 3,598,025 Financial Liabilities: Time deposits $1,255,108 $1,269,433 $— $1,269,433 $— FHLB advances 950,722 950,691 — 950,691 — Junior subordinated debentures 22,681 19,226 — 19,226 —

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The following table summarizes total revenues as presented in the Consolidated Statements of Income and the related amounts which are from contracts with customers within the scope of ASC 606. As shown below, a substantial portion of our revenues are specifically excluded from the scope of ASC 606. Years ended December 31, 2019 2018 2017 (Dollars in thousands) Revenue (1) ASC 606 Revenue (2) Revenue (1) ASC 606 Revenue (2) Revenue (1) ASC 606 Revenue (2) Net interest income $133,414 $— $132,290 $— $119,531 $— Noninterest income: Asset-based wealth management revenues 35,806 35,806 37,343 37,343 38,125 38,125 Transaction-based wealth management revenues 1,042 1,042 998 998 1,221 1,221 Total wealth management revenues 36,848 36,848 38,341 38,341 39,346 39,346 Mortgage banking revenues 14,795 — 10,381 — 11,392 — Card interchange fees 4,214 4,214 3,768 3,768 3,502 3,502 Service charges on deposit accounts 3,684 3,684 3,628 3,628 3,672 3,672 Loan related derivative income 3,993 — 2,461 — 3,214 — Income from bank-owned life insurance 2,354 — 2,196 — 2,161 — Net realized losses on securities (53 ) — — — — — Other income 1,245 1,184 1,339 1,329 1,522 1,469 Total noninterest income 67,080 45,930 62,114 47,066 64,809 47,989 Total revenues $200,494 $45,930 $194,404 $47,066 $184,340 $47,989 (1) As reported in the Consolidated Statements of Income. (2) Revenue from contracts with customers in scope of ASC 606. The following table presents revenue from contracts with customers based on the timing of revenue recognition: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Revenue recognized at a point in time: Card interchange fees $4,214 $3,768 $3,502 Service charges on deposit accounts 2,850 2,802 2,899 Other income 989 958 1,122 Revenue recognized over time: Wealth management revenues 36,848 38,341 39,346 Service charges on deposit accounts 834 826 773 Other income 195 371 347 Total revenues from contracts in scope of ASC 606 $45,930 $47,066 $47,989 Receivables primarily consist of amounts due from customers for wealth management services performed for which the Corporation’s performance obligations have been fully satisfied. Receivables amounted to $4.5 million and $4.8 million , respectively, at December 31, 2019 and 2018 and were included in other assets in the Consolidated Balance Sheets. Deferred revenues, which are considered contract liabilities under ASC 606, represent advance consideration received from customers for which the Corporation has a remaining performance obligation to fulfill. Contract liabilities are recognized as revenue over the life of the contract as the performance obligations are satisfied. The balances of contract liabilities were insignificant at both December 31, 2019 and 2018 and were included in other liabilities in the Consolidated Balance Sheets. For commissions and incentives that are in-scope of ASC 606, such as those paid to employees in our wealth management services and commercial banking segments in order to obtain customer contracts, contract cost assets are established. The contract cost assets are capitalized and amortized over the estimated useful life that the asset is expected to generate benefits. The carrying value of contract cost assets amounted to $905 thousand at December 31, 2019 , compared to $458 thousand at December 31, 2018 and were included in other assets in the Consolidated Balance Sheets.

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Employee Benefits	Employee Benefits Defined Benefit Pension Plans Washington Trust maintains a qualified pension plan for the benefit of certain eligible employees who were hired prior to October 1, 2007. Washington Trust also has non-qualified retirement plans to provide supplemental retirement benefits to certain employees, as defined in the plans. The defined benefit pension plans were previously amended to freeze benefit accruals after a 10 -year transition period ending in December 2023. The qualified pension plan is funded on a current basis, in compliance with the requirements of ERISA. Pension benefit costs and benefit obligations incorporate various actuarial and other assumptions, including discount rates, mortality, rates of return on plan assets and compensation increases. Washington Trust evaluates these assumptions annually. The following table presents the plans’ projected benefit obligations, fair value of plan assets and funded (unfunded) status: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2019 2018 2019 2018 Change in Benefit Obligation: Benefit obligation at beginning of period $73,380 $80,723 $14,626 $15,203 Service cost 2,037 2,244 126 108 Interest cost 2,967 2,715 563 475 Actuarial loss (gain) 10,453 (7,830 ) 2,028 (252 ) Benefits paid (5,546 ) (4,344 ) (905 ) (908 ) Administrative expenses (150 ) (128 ) — — Benefit obligation at end of period 83,141 73,380 16,438 14,626 Change in Plan Assets: Fair value of plan assets at beginning of period 86,180 87,364 — — Actual return on plan assets 13,265 288 — — Employer contributions — 3,000 905 908 Benefits paid (5,546 ) (4,344 ) (905 ) (908 ) Administrative expenses (150 ) (128 ) — — Fair value of plan assets at end of period 93,749 86,180 — — Funded (unfunded) status at end of period $10,608 $12,800 ($16,438 ) ($14,626 ) As of December 31, 2019 and 2018 , the funded status of the qualified defined benefit pension plan amounted to $10.6 million and $12.8 million , respectively, and was included in other assets in the Consolidated Balance Sheets. The unfunded status of the non-qualified defined benefit retirement plans was $16.4 million and $14.6 million , respectively, at December 31, 2019 and December 31, 2018 and was included in other liabilities in the Consolidated Balance Sheets. The non-qualified retirement plans provide for the designation of assets in rabbi trusts. Securities available for sale and other short-term investments designated for this purpose, with the carrying value of $14.3 million and $14.6 million are included in the Consolidated Balance Sheets at December 31, 2019 and 2018 , respectively. The following table presents components of accumulated other comprehensive income related to the qualified pension plan and non-qualified retirement plans, on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2019 2018 2019 2018 Net actuarial loss $10,343 $9,453 $7,405 $5,785 Prior service credit — (16 ) — — Total pre-tax amounts recognized in accumulated other comprehensive income $10,343 $9,437 $7,405 $5,785 The accumulated benefit obligation for the qualified pension plan was $76.6 million and $67.4 million at December 31, 2019 and 2018 , respectively. The accumulated benefit obligation for the non-qualified retirement plans amounted to $14.9 million and $13.2 million at December 31, 2019 and 2018 , respectively. The following table presents components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss), on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ended December 31, 2019 2018 2017 2019 2018 2017 Net Periodic Benefit Cost: Service cost (1) $2,037 $2,244 $2,149 $126 $108 $129 Interest cost (2) 2,967 2,715 2,673 563 475 428 Expected return on plan assets (2) (4,495 ) (5,272 ) (4,942 ) — — — Amortization of prior service credit (2) (16 ) (23 ) (23 ) — (1 ) (1 ) Recognized net actuarial loss (2) 792 1,496 1,114 408 411 347 Net periodic benefit cost 1,285 1,160 971 1,097 993 903 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (on a pre-tax basis): Net loss (gain) 890 (4,342 ) (1,798 ) 1,620 (663 ) 1,928 Prior service credit 16 23 23 — 1 1 Recognized in other comprehensive income (loss) 906 (4,319 ) (1,775 ) 1,620 (662 ) 1,929 Total recognized in net periodic benefit cost and other comprehensive income (loss) $2,191 ($3,159 ) ($804 ) $2,717 $331 $2,832 (1) Included in salaries and employee benefits expense in the Consolidated Statements of Income. (2) Included in other expenses in the Consolidated Statements of Income. For the qualified pension plan, net losses of $1.6 million will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost during the year 2020 . There are no estimated prior service credits to be amortized in 2020 for the qualified pension plan. For the non-qualified retirement plans, net losses of $559 thousand will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost during the year 2020 . There are no estimated prior service credits to be amortized in 2020 for the non-qualified retirement plans. Assumptions The following table presents the measurement date and weighted-average assumptions used to determine benefit obligations at December 31, 2019 and 2018 : Qualified Pension Plan Non-Qualified Retirement Plans 2019 2018 2019 2018 Measurement date Dec 31, 2019 Dec 31, 2018 Dec 31, 2019 Dec 31, 2018 Discount rate 3.42 % 4.38 % 3.30 % 4.30 % Rate of compensation increase 3.75 3.75 3.75 3.75 The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31, 2019 , 2018 and 2017 : Qualified Pension Plan Non-Qualified Retirement Plans 2019 2018 2017 2019 2018 2017 Measurement date Dec 31, 2018 Dec 31, 2017 Dec 31, 2016 Dec 31, 2018 Dec 31, 2017 Dec 31, 2016 Equivalent single discount rate for benefit obligations 4.38 % 3.69 % 4.18 % 4.28 % 3.58 % 3.96 % Equivalent single discount rate for service cost 4.44 3.76 4.29 4.48 3.79 4.25 Equivalent single discount rate for interest cost 4.12 3.42 3.73 3.98 3.22 3.36 Expected long-term return on plan assets 5.75 6.75 6.75 N/A N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75 3.75 3.75 The expected long-term rate of return on plan assets is based on what the Corporation believes is realistically achievable based on the types of assets held by the plan and the plan’s investment practices. The assumption is updated annually, taking into account the asset allocation, historical asset return trends on the types of assets held and the current and expected economic conditions. Future decreases in the long-term rate of return assumption on plan assets would increase pension costs and, in general, may increase the requirement to make funding contributions to the plans. Future increases in the long-term rate of return on plan assets would have the opposite effect. The discount rate assumption for defined benefit pension plans is reset on the measurement date. Discount rates are selected for each plan by matching expected future benefit payments stream to a yield curve based on a selection of high- quality fixed-income debt securities. Future decreases in discount rates would increase the present value of pension obligations and increase our pension costs, while future increases in discount rates would have the opposite effect. The "spot rate approach" was utilized in the calculation of interest and service cost. The spot rate approach applies separate discount rates for each projected benefit payment in the calculation of interest and service cost. This approach provides a more precise measurement of service and interest cost by improving the correlation between projected benefit cash flows and their corresponding spot rates. Plan Assets The following tables present the fair values of the qualified pension plan’s assets: (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2019 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $9,902 $— $— $9,902 Obligations of U.S. government-sponsored enterprises — 28,615 — 28,615 Obligations of states and political subdivisions — 2,998 — 2,998 Corporate bonds — 10,033 — 10,033 Common stocks 14,593 — — 14,593 Mutual funds 27,608 — — 27,608 Total plan assets $52,103 $41,646 $— $93,749 (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2018 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $25,986 $— $— $25,986 Obligations of U.S. government-sponsored enterprises — 21,787 — 21,787 Obligations of states and political subdivisions — 2,597 — 2,597 Corporate bonds — 10,361 — 10,361 Common stocks 9,957 — — 9,957 Mutual funds 15,492 — — 15,492 Total plan assets $51,435 $34,745 $— $86,180 The qualified pension plan uses fair value measurements to record fair value adjustments to the securities held in its investment portfolio. When available, the qualified pension plan uses quoted market prices to determine the fair value of securities; such items are classified as Level 1. This category includes cash and cash equivalents, as well as common stocks and mutual funds which are exchange-traded. Level 2 securities in the qualified pension plan include debt securities with quoted prices, which are traded less frequently than exchange-traded instruments, whose values are determined using matrix pricing with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. This category includes obligations of U.S. government-sponsored enterprises, obligations of states and political subdivisions and corporate bonds. In certain cases where there is limited activity or less transparency around inputs to the valuation, securities may be classified as Level 3. As of December 31, 2019 and 2018 , the qualified pension plan did not have any securities in the Level 3 category. The following table presents the asset allocations of the qualified pension plan, by asset category: December 31, 2019 2018 Asset Category: Cash and cash equivalents 10.6 % 30.2 % Fixed income securities 44.4 40.3 Equity securities 45.0 29.5 Total 100.0 % 100.0 % The assets of the qualified defined benefit pension plan trust (the “Pension Trust”) are managed to ensure that all present and future benefit obligations are met as they come due. It seeks to achieve this goal while trying to mitigate volatility in plan funded status, contributions and expense by better matching the characteristics of the plan assets to that of the plan liabilities. As benefit accruals under the qualified plan will be frozen on December 31, 2023, asset allocations have been and will continue to be refined. Cash inflow is typically comprised of investment income from portfolio holdings and Bank contributions, while cash outflow is for the purpose of paying plan benefits and certain plan expenses. As early as possible each year, the trustee is advised of the projected schedule of employer contributions and estimations of benefit payments. The investment philosophy used for the Pension Trust emphasizes consistency of results over an extended market cycle, while reducing the impact of the volatility of the security markets upon investment results. The assets of the Pension Trust should be protected by substantial diversification of investments, providing exposure to a wide range of quality investment opportunities in various asset classes, with a high degree of liquidity. Fixed income bond investments will typically be limited to investment grade securities in the top four categories used by the major credit rating agencies. High yield bond funds may be used to provide exposure to this asset class as a diversification tool. In order to reduce the volatility of the annual rate of return of the bond portfolio, attention will be given to the maturity structure of the portfolio in the light of money market conditions and interest rate forecasts. The assets of the Pension Trust will typically have a laddered maturity structure, avoiding large concentrations in any single year. Equity holdings provide opportunities for dividend and capital appreciation returns. Holdings will be appropriately diversified by maintaining broad exposure to large-, mid- and small-cap stocks as well as international equities. Investment selection and mix of equity holdings should be influenced by forecasts of economic activity, corporate profits and allocation among different segments of the economy while ensuring efficient diversification. The fair value of equity securities of any one issuer will not be permitted to exceed 10% of the total fair value of equity holdings of the Pension Trust. Cash Flows Contributions The Internal Revenue Code permits flexibility in plan contributions so that normally a range of contributions is possible. The Corporation does not expect to make a contribution to the qualified pension plan in 2020 . In addition, the Corporation expects to contribute $898 thousand in benefit payments to the non-qualified retirement plans in 2020 . Estimated Future Benefit Payments The following table presents the benefit payments, which reflect expected future service, as appropriate, expected to be paid: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ending December 31, 2020 $4,748 $898 2021 3,803 887 2022 4,083 878 2023 4,574 876 2024 4,588 871 2025 and thereafter 27,957 4,343 401(k) Plan The Corporation’s 401(k) Plan provides a match up to a maximum of 3% of employee contributions for substantially all employees. In addition, substantially all employees hired after September 30, 2007, who are ineligible for participation in the qualified defined benefit pension plan, receive a non-elective employer contribution of 4% of compensation. Total employer matching contributions under this plan amounted to $2.7 million , $2.5 million and $2.3 million in 2019 , 2018 and 2017 , respectively. Other Incentive Plans The Corporation maintains several non-qualified incentive compensation plans. Substantially all employees participate in one of the incentive compensation plans. Incentive plans provide for annual or more frequent payments based on individual, business line and/or corporate performance targets. Total incentive based compensation in 2019 , 2018 and 2017 amounted to $16.7 million , $16.1 million and $16.9 million , respectively. In general, the terms of incentive plans are subject to annual renewal and may be terminated at any time by the Compensation Committee of the Board of Directors. Deferred Compensation Plan The Amended and Restated Nonqualified Deferred Compensation Plan provides supplemental retirement and tax benefits to directors and certain officers. The plan is funded primarily through pre-tax contributions made by the participants. The assets and liabilities of the Deferred Compensation Plan are recorded at fair value in the Corporation’s Consolidated Balance Sheets. The participants in the plan bear the risk of market fluctuations of the underlying assets. The accrued liability related to this plan amounted to $17.9 million and $15.7 million , respectively, at December 31, 2019 and 2018 , and is included in other liabilities on the accompanying Consolidated Balance Sheets. The corresponding invested assets are reported in other assets in the Consolidated Balance Sheets.

Share-Based Compensation Arrang

Share-Based Compensation Arrangements	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Share-Based Compensation Arrangements	Share-Based Compensation Arrangements Washington Trust’s share-based compensation plans are described below. The 2013 Stock Option and Incentive Plan (the “2013 Plan”) was approved by shareholders on April 23, 2013. Under the 2013 Plan, the maximum number of shares of the Bancorp’s common stock to be issued is 1,748,250 . The 2013 Plan permits the granting of stock options and other equity incentives to officers, employees, directors and other key persons. The 2003 Stock Incentive Plan (the “2003 Plan”) was amended and restated and approved by shareholders in April 2009. Under the 2003 Plan, as amended and restated, the maximum number of shares of Bancorp’s common stock to be issued was 1,200,000 shares and the number of shares that could be issued in the form of awards other than stock options or stock appreciation rights was 400,000 . The 2003 Plan permitted the granting of stock options and other equity incentives to officers, employees, directors and other key persons until the 2003 Plan’s expiration on April 28, 2019. The exercise price of each stock option may not be less than the fair market value of the Bancorp’s common stock on the date of grant, and options shall have a term of no more than ten years. Stock options are designated as either non-qualified or incentive stock options. In general, the stock option price is payable in cash, by the delivery of shares of common stock already owned by the grantee, or a combination thereof. With respect only to non-qualified stock option grants issued under the 2013 Plan, the exercise may also be accomplished by withholding the exercise price from the number of shares that would otherwise be delivered upon a cash exercise of the option. Performance share awards are granted in order to provide certain key employees of the Corporation the opportunity to earn shares of common stock, the number of which is determined pursuant to, and subject to the attainment of, performance goals during a specified measurement period. The number of shares vested and earned will be contingent upon the Corporation’s attainment of certain performance measures as detailed in the performance share award agreements. Vesting of stock options and share awards may accelerate or may be subject to proportional vesting if there is a change in control, disability, retirement or death (as defined in the 2013 Plan and the 2003 Plan). The following table presents share-based compensation expense and the related income tax benefits recognized in the Consolidated Statements of Income for stock options, nonvested share units and nonvested performance share units: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Share-based compensation expense $3,124 $2,602 $2,577 Related income tax benefits (1) $982 $1,108 $1,114 (1) Includes $248 thousand , $496 thousand , and $508 thousand , respectively, of excess tax benefits recognized upon the settlement of share-based compensation awards in 2019 , 2018 and 2017 . As of December 31, 2019 , there was $5.0 million of total unrecognized compensation cost related to share-based compensation arrangements, including stock options, nonvested share units and performance share units granted under the Plans. That cost is expected to be recognized over a weighted average period of 2.01 years. Stock Options Washington Trust uses historical data to estimate stock option exercise and employee departure behavior in the option-pricing model. The expected term of options granted was derived from the output of the option valuation model and represents the period of time that options granted are expected to be outstanding. Expected volatility was based on historical volatility of Washington Trust shares. The risk-free rate for periods within the contractual life of the stock option was based on the U.S. Treasury yield curve in effect at the date of grant. The following presents the assumptions used in determining the grant date fair value of the stock option awards granted to certain key employees: 2019 2018 2017 Options granted 61,800 47,950 47,725 Cliff vesting period (years) 3 3 3 Expected term (years) 6.5 6.5 7.0 Expected dividend yield 3.40 % 3.39 % 3.57 % Weighted average expected volatility 23.05 % 22.73 % 27.10 % Weighted average risk-free interest rate 1.71 % 3.14 % 1.70 % Weighted average grant-date fair value $7.44 $9.74 $10.60 The following table presents a summary of the status of Washington Trust’s stock options outstanding as of and for the year ended December 31, 2019 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (000’s) Beginning of period 222,615 $42.92 Granted 61,800 48.65 Exercised (35,600 ) 35.70 Forfeited or expired — — End of period 248,815 $45.38 7.27 $2,308 At end of period: Options exercisable 95,240 $33.57 4.71 $1,926 Options expected to vest in future periods 153,575 $52.70 8.85 $382 The total intrinsic value is the amount by which the fair value of the underlying stock exceeds the exercise price of an option on the exercise date. The following table presents additional information concerning options outstanding and options exercisable at December 31, 2019 : Options Outstanding Options Exercisable Exercise Price Ranges Number of Shares Weighted Average Remaining Life (Years) Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $15.01 to $20.00 4,100 0.42 $17.52 4,100 $17.52 $20.01 to $25.00 22,015 2.14 22.89 22,015 22.89 $25.01 to $30.00 — — — — — $30.01 to $35.00 19,775 4.16 32.76 19,775 32.76 $35.01 to $40.00 22,100 5.72 39.22 18,100 39.55 $40.01 to $45.00 31,250 6.80 40.25 31,250 40.25 $45.01 to $50.00 61,800 9.80 48.65 — — $50.01 to $55.00 47,950 8.80 54.74 — — $55.01 to $60.00 39,825 7.80 58.05 — — 248,815 7.27 $45.38 95,240 $33.57 The total intrinsic value of stock options exercised during the years ended December 31, 2019 , 2018 and 2017 was $580 thousand , $833 thousand and $1.0 million , respectively. Nonvested Share Units In 2019 , 2018 and 2017 , the Corporation granted to directors and certain key employees 26,070 , 13,430 and 15,900 nonvested share units, respectively, with 3 - to 5 -year cliff vesting. The following table presents a summary of the status of Washington Trust’s nonvested share units as of and for the year ended December 31, 2019 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 45,350 $48.73 Granted 26,070 49.81 Vested (17,530 ) 40.26 Forfeited — — End of period 53,890 $52.01 Nonvested Performance Share Units The Corporation granted performance share units to certain key employees providing the opportunity to earn shares of common stock over a 3 - to 5 -year performance period. The following table presents a summary of the performance share unit awards as of December 31, 2019 : Grant Date Fair Value per Share Weighted Average Current Performance Assumption Expected Number of Shares Performance share units awarded in: 2019 $52.84 138% 43,360 2018 54.25 140% 41,454 2017 51.85 150% 24,150 Total 108,964 The following table presents a summary of the status of Washington Trust’s performance share units as of and for the year ended December 31, 2019 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 93,604 $48.20 Granted 43,360 52.84 Vested (28,239 ) 36.11 Forfeited 239 36.11 End of period 108,964 $53.16

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Business Segments	Business Segments Washington Trust segregates financial information in assessing its results among its Commercial Banking and Wealth Management Services operating segments. The amounts in the Corporate unit include activity not related to the segments. Commercial Banking The Commercial Banking segment includes commercial, residential and consumer lending activities; mortgage banking activities; deposit generation; cash management activities; and direct banking activities, which include the operation of ATMs, telephone and internet banking services and customer support and sales. Wealth Management Services Wealth Management Services includes investment management; financial planning; personal trust and estate services, including services as trustee, personal representative, custodian and guardian; and settlement of decedents’ estates. Institutional trust services are also provided, including fiduciary services. Corporate Corporate includes the Treasury Unit, which is responsible for managing the wholesale investment portfolio and wholesale funding needs. It also includes income from BOLI, as well as administrative and executive expenses not allocated to the operating segments and the residual impact of methodology allocations such as FTP offsets. The following tables present the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Year ended December 31, 2019 Commercial Wealth Corporate Consolidated Net interest income (expense) $112,414 ($438 ) $21,438 $133,414 Provision for loan losses 1,575 — — 1,575 Net interest income (expense) after provision for loan losses 110,839 (438 ) 21,438 131,839 Noninterest income 27,857 36,856 2,367 67,080 Noninterest expenses: Depreciation and amortization expense 2,630 1,445 159 4,234 Other noninterest expenses 66,517 26,057 13,932 106,506 Total noninterest expenses 69,147 27,502 14,091 110,740 Income before income taxes 69,549 8,916 9,714 88,179 Income tax expense 15,189 2,308 1,564 19,061 Net income $54,360 $6,608 $8,150 $69,118 Total assets at period end $4,070,594 $74,990 $1,147,075 $5,292,659 Expenditures for long-lived assets 2,521 445 166 3,132 (Dollars in thousands) Year ended December 31, 2018 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $106,668 ($334 ) $25,956 $132,290 Provision for loan losses 1,550 — — 1,550 Net interest income (expense) after provision for loan losses 105,118 (334 ) 25,956 130,740 Noninterest income 21,509 38,341 2,264 62,114 Noninterest expenses: Depreciation and amortization expense 2,589 1,501 171 4,261 Other noninterest expenses 62,673 26,222 13,006 101,901 Total noninterest expenses 65,262 27,723 13,177 106,162 Income before income taxes 61,365 10,284 15,043 86,692 Income tax expense 13,149 2,577 2,534 18,260 Net income $48,216 $7,707 $12,509 $68,432 Total assets at period end $3,804,021 $71,254 $1,135,491 $5,010,766 Expenditures for long-lived assets 3,415 407 152 3,974 (Dollars in thousands) Year ended December 31, 2017 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $98,736 ($167 ) $20,962 $119,531 Provision for loan losses 2,600 — — 2,600 Net interest income (expense) after provision for loan losses 96,136 (167 ) 20,962 116,931 Noninterest income 23,244 39,346 2,219 64,809 Noninterest expenses: Depreciation and amortization expense 2,604 1,689 196 4,489 Other noninterest expenses 60,828 26,718 12,065 99,611 Total noninterest expenses 63,432 28,407 12,261 104,100 Income before income taxes 55,948 10,772 10,920 77,640 Income tax expense 23,876 3,795 4,044 31,715 Net income $32,072 $6,977 $6,876 $45,925 Total assets at period end $3,491,845 $66,083 $971,922 $4,529,850 Expenditures for long-lived assets 2,224 360 195 2,779

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) The following tables present the activity in other comprehensive income (loss): (Dollars in thousands) Year ended December 31, 2019 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $26,074 $6,127 $19,947 Net losses on securities reclassified into earnings (1) 53 12 41 Net change in fair value of available for sale debt securities 26,127 6,139 19,988 Cash flow hedges: Changes in fair value of cash flow hedges (1,444 ) (339 ) (1,105 ) Net cash flow hedge losses reclassified into earnings (2) 159 38 121 Net change in the fair value of cash flow hedges (1,285 ) (301 ) (984 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (3,710 ) (872 ) (2,838 ) Amortization of net actuarial losses (3) 1,200 282 918 Amortization of net prior service credits (3) (16 ) (4 ) (12 ) Net change in defined benefit plan obligations (2,526 ) (594 ) (1,932 ) Total other comprehensive income $22,316 $5,244 $17,072 (1) The pre-tax amount is reported as net realized losses on securities in the Consolidated Statements of Income. (2) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2018 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities ($12,063 ) ($2,835 ) ($9,228 ) Net (gains) losses on securities reclassified into earnings — — — Net change in fair value of available for sale debt securities (12,063 ) (2,835 ) (9,228 ) Cash flow hedges: Changes in fair value of cash flow hedges 639 151 488 Net cash flow hedge losses reclassified into earnings (1) 170 39 131 Net change in the fair value of cash flow hedges 809 190 619 Defined benefit plan obligations: Defined benefit plan obligation adjustment 3,098 729 2,369 Amortization of net actuarial losses (2) 1,907 448 1,459 Amortization of net prior service credits (2) (24 ) (6 ) (18 ) Net change in defined benefit plan obligations 4,981 1,171 3,810 Total other comprehensive loss ($6,273 ) ($1,474 ) ($4,799 ) (1) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (2) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2017 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $986 $365 $621 Net (gains) losses on securities reclassified into earnings — — — Net change in fair value of available for sale debt securities 986 365 621 Cash flow hedges: Changes in fair value of cash flow hedges (774 ) (223 ) (551 ) Net cash flow hedge losses reclassified into earnings (1) 792 293 499 Net change in the fair value of cash flow hedges 18 70 (52 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (1,591 ) (594 ) (997 ) Amortization of net actuarial losses (2) 1,461 546 915 Amortization of net prior service credits (2) (24 ) (9 ) (15 ) Net change in defined benefit plan obligations (154 ) (57 ) (97 ) Total other comprehensive income $850 $378 $472 (1) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (2) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income. The following tables present the changes in accumulated other comprehensive income (loss) by component, net of tax: (Dollars in thousands) Net Unrealized (Losses) Gains on Available For Sale Debt Securities Net Unrealized Gains (Losses) on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2018 ($16,762 ) $191 ($11,738 ) ($28,309 ) Other comprehensive income (loss) before reclassifications 19,947 (1,105 ) (2,838 ) 16,004 Amounts reclassified from accumulated other comprehensive income 41 121 906 1,068 Net other comprehensive income (loss) 19,988 (984 ) (1,932 ) 17,072 Balance at December 31, 2019 $3,226 ($793 ) ($13,670 ) ($11,237 ) (Dollars in thousands) Net Unrealized Losses on Available For Sale Debt Securities Net Unrealized (Losses) Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2017 ($7,534 ) ($428 ) ($15,548 ) ($23,510 ) Other comprehensive (loss) income before reclassifications (9,228 ) 488 2,369 (6,371 ) Amounts reclassified from accumulated other comprehensive income — 131 1,441 1,572 Net other comprehensive (loss) income (9,228 ) 619 3,810 (4,799 ) Balance at December 31, 2018 ($16,762 ) $191 ($11,738 ) ($28,309 ) (Dollars in thousands) Net Unrealized (Losses) Gains on Available For Sale Debt Securities Net Unrealized Losses on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2016 ($6,825 ) ($300 ) ($12,632 ) ($19,757 ) Other comprehensive income (loss) before reclassifications 621 (551 ) (741 ) (671 ) Amounts reclassified from accumulated other comprehensive income — 499 644 1,143 Net other comprehensive income (loss) 621 (52 ) (97 ) 472 Reclassification of income tax effects due to the adoption of ASU 2018-02 (1,330 ) (76 ) (2,819 ) (4,225 ) Balance at December 31, 2017 ($7,534 ) ($428 ) ($15,548 ) ($23,510 )

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings per Common Share The following table presents the calculation of earnings per common share: (Dollars and shares in thousands, except per share amounts) Years ended December 31, 2019 2018 2017 Earnings per common share - basic: Net income $69,118 $68,432 $45,925 Less dividends and undistributed earnings allocated to participating securities (139 ) (144 ) (108 ) Net income available to common shareholders $68,979 $68,288 $45,817 Weighted average common shares 17,331 17,272 17,207 Earnings per common share - basic $3.98 $3.95 $2.66 Earnings per common share - diluted: Net income $69,118 $68,432 $45,925 Less dividends and undistributed earnings allocated to participating securities (139 ) (144 ) (108 ) Net income available to common shareholders $68,979 $68,288 $45,817 Weighted average common shares 17,331 17,272 17,207 Dilutive effect of common stock equivalents 83 119 131 Weighted average diluted common shares 17,414 17,391 17,338 Earnings per common share - diluted $3.96 $3.93 $2.64 Weighted average common stock equivalents, not included in common stock equivalents above because they were anti-dilutive, totaled 100,643 , 55,821 and 11,572 , respectively, for the years ended December 31, 2019 , 2018 and 2017 .

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	Leases The Corporation adopted the provisions of ASC 842 on January 1, 2019. Upon adoption, operating lease ROU assets totaling $28.9 million and operating lease liabilities totaling $30.9 million were recognized in our Consolidated Balance Sheets for leases that existed at the adoption date, based on the present value of lease payments over the remaining lease term. The weighted average discount rate used to discount operating lease liabilities at December 31, 2019 was 3.67% . As of December 31, 2019 , the Corporation has one lease that has not yet commenced. At December 31, 2019 , lease expiration dates ranged from 4 months to 21 years, with additional renewal options on certain leases ranging from 1 to 5 years. At December 31, 2019 , the weighted average remaining lease term for the Corporation’s operating leases was 14.0 years. Rental expense for operating leases amounted to $3.8 million for 2019 , compared to $3.7 million for 2018 . The following table presents the undiscounted annual lease payments under the terms of the Corporation’s operating leases at December 31, 2019 , including a reconciliation to the present value of operating lease liabilities recognized in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Years ending December 31: 2020 $3,493 2021 3,291 2022 3,165 2023 3,097 2024 2,904 2025 and thereafter 21,818 Total operating lease payments (1) 37,768 Less interest 8,907 Present value of operating lease liabilities (2) $28,861 (1) Includes $2.4 million related to options to extend lease terms that are reasonably certain of being exercised. (2) Includes short-term operating lease liabilities of $2.5 million . The following table presents the components of total lease expense and operating cash flows: (Dollars in thousands) Year ended December 31, 2019 Lease Expense: Operating lease expense $3,724 Variable lease expense 49 Total lease expense (1) $3,773 Cash Paid: Cash paid reducing operating lease liabilities $3,586 (1) Included in net occupancy expenses in the Consolidated Income Statement. The following table presents the minimum annual lease payments under the terms of these leases, exclusive of renewal provisions at December 31, 2018 : (Dollars in thousands) Years ending December 31: 2019 $3,544 2020 2,980 2021 2,677 2022 2,293 2023 2,059 2024 and thereafter 22,648 Total minimum lease payments $36,201 At December 31, 2018 , lease expiration dates ranged from 5 months to 22 years, with additional renewal options on certain leases ranging from 1 to 5 years.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Financial Instruments with Off-Balance Risk The Corporation is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers and to manage the Corporation’s exposure to fluctuations in interest rates. These financial instruments include commitments to extend credit, standby letters of credit, forward loan commitments, loan related derivative contracts and interest rate risk management contracts. These instruments involve, to varying degrees, elements of credit risk in excess of the amount recognized in the Corporation’s Consolidated Balance Sheets. The contract or notional amounts of these instruments reflect the extent of involvement the Corporation has in particular classes of financial instruments. The Corporation’s credit policies with respect to interest rate swap agreements with commercial borrowers, commitments to extend credit and financial guarantees are similar to those used for loans. The interest rate swaps with other counterparties are generally subject to bilateral collateralization terms. The following table presents the contractual and notional amounts of financial instruments with off-balance sheet risk: (Dollars in thousands) December 31, 2019 2018 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $471,338 $533,884 Home equity lines 295,687 270,462 Other loans 88,613 46,698 Standby letters of credit 13,710 7,706 Financial instruments whose notional amounts exceed the amount of credit risk: Mortgage loan commitments: Interest rate lock commitments 51,439 30,766 Forward sale commitments 94,829 61,993 Loan related derivative contracts: Interest rate swaps with customers 813,458 648,050 Mirror swaps with counterparties 813,458 648,050 Risk participation-in agreements 72,866 46,510 Foreign exchange contracts — 2,784 Interest rate risk management contracts: Interest rate swaps 60,000 60,000 See Note 13 for additional disclosure pertaining to derivative financial instruments. Commitments to Extend Credit Commitments to extend credit are agreements to lend to a customer as long as there are no violations of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since some of the commitments are expected to expire without being drawn upon, total commitment amounts do not necessarily represent future cash requirements. Each borrower’s creditworthiness is evaluated on a case-by-case basis. The amount of collateral obtained is based on management’s credit evaluation of the borrower. Standby Letters of Credit Standby letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. These standby letters of credit are primarily issued to support the financing needs of the Bank’s commercial customers. The credit risk involved in issuing standby letters of credit is essentially the same as that involved in extending loan facilities to customers. The collateral supporting those commitments is essentially the same as for other commitments. Most standby letters of credit extend for one year . The maximum potential amount of undiscounted future payments, not reduced by amounts that may be recovered totaled $13.7 million and $7.7 million , as of December 31, 2019 and 2018 , respectively. At December 31, 2019 and 2018 , there were no liabilities to beneficiaries resulting from standby letters of credit. Fee income on standby letters of credit was insignificant for the years ended December 31, 2019 , 2018 and 2017 . At December 31, 2019 and 2018 , a substantial portion of the standby letters of credit were supported by pledged collateral. The collateral obtained is determined based on management’s credit evaluation of the customer. Should the Corporation be required to make payments to the beneficiary, repayment from the customer to the Corporation is required. Mortgage Loan Commitments Interest rate lock commitments are extended to borrowers and relate to the origination of mortgage loans held for sale. To mitigate the interest rate risk and pricing risk associated with these rate locks and mortgage loans held for sale, the Corporation enters into forward sale commitments. Both interest rate lock commitments and forward sale commitments are derivative financial instruments. Other Contingencies Litigation The Corporation is involved in various claims and legal proceedings arising out of the ordinary course of business. Management is of the opinion, based on its review with counsel of the development of such matters to date, that the ultimate disposition of such matters will not materially affect the consolidated financial position or results of operations of the Corporation. Other When selling a residential real estate mortgage loan or acting as originating agent on behalf of a third party, Washington Trust generally makes various representations and warranties. The specific representations and warranties depend on the nature of the transaction and the requirements of the buyer. Contractual liability may arise when the representations and warranties are breached. In the event of a breach of these representations and warranties, Washington Trust may be required to either repurchase the residential real estate mortgage loan (generally at unpaid principal balance plus accrued interest) with the identified defects or indemnify (“make-whole”) the investor for its losses. In the case of a repurchase, the Corporation will bear any subsequent credit loss on the residential real estate mortgage loan. Washington Trust has experienced an insignificant number of repurchase demands over a period of many years. As of December 31, 2019 and 2018 , the carrying value of loans repurchased due to representation and warranty claims was $1.7 million and $1.2 million , respectively. Washington Trust has recorded a reserve for its exposure to losses for premium recapture and the obligation to repurchase previously sold residential real estate mortgage loans. The reserve balance amounted to $170 thousand and $140 thousand at December 31, 2019 and 2018 , respectively, and is included in other liabilities in the Consolidated Balance Sheets. Any change in the estimate is recorded in mortgage banking revenues in the Consolidated Statements of Income.

Parent Company Financial Statem

Parent Company Financial Statements	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Parent Company Financial Statements	Parent Company Financial Statements The following tables present parent company only financial statements of the Bancorp, reflecting the investment in the Bank on the equity basis of accounting. The Statements of Changes in Shareholders’ Equity for the parent company only are identical to the Consolidated Statements of Changes in Shareholders’ Equity and are therefore not presented. Balance Sheets (Dollars in thousands, except par value) December 31, 2019 2018 Assets: Cash on deposit with bank subsidiary $1,838 $1,912 Investment in subsidiaries at equity value: Bank 521,969 467,657 Non-bank 1,882 1,869 Dividends receivable from bank subsidiary 9,575 7,762 Other assets 232 190 Total assets $535,496 $479,390 Liabilities: Junior subordinated debentures $22,681 $22,681 Dividends payable 9,252 8,439 Other liabilities 71 86 Total liabilities 32,004 31,206 Shareholders’ Equity: Common stock of $.0625 par value; authorized 60,000,000 shares; issued and outstanding 17,363,455 shares in 2019 and 17,302,037 in 2018 1,085 1,081 Paid-in capital 123,281 119,888 Retained earnings 390,363 355,524 Accumulated other comprehensive loss (11,237 ) (28,309 ) Total shareholders’ equity 503,492 448,184 Total liabilities and shareholders’ equity $535,496 $479,390 Statements of Income (Dollars in thousands) Years ended December 31, 2019 2018 2017 Income: Dividends from subsidiaries: Bank $36,796 $32,394 $27,900 Non-bank 27 24 18 Total income 36,823 32,418 27,918 Expenses: Interest on junior subordinated debentures 980 869 613 Legal and professional fees 147 187 169 Change in fair value of contingent consideration — (187 ) (643 ) Other 337 324 298 Total expenses 1,464 1,193 437 Income before income taxes 35,359 31,225 27,481 Income tax benefit 301 284 340 Income before equity in undistributed earnings (losses) of subsidiaries 35,660 31,509 27,821 Equity in undistributed earnings (losses) of subsidiaries: Bank 33,445 36,876 18,193 Non-bank 13 47 (89 ) Net income $69,118 $68,432 $45,925 Statements of Cash Flows (Dollars in thousands) Years ended December 31, 2019 2018 2017 Cash flow from operating activities: Net income $69,118 $68,432 $45,925 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed (earnings) losses of subsidiaries: Bank (33,445 ) (36,876 ) (18,193 ) Non-bank (13 ) (47 ) 89 (Increase) decrease in dividend receivable (1,813 ) 8 (1,252 ) (Increase) decrease in other assets (43 ) 70 72 (Decrease) increase in accrued expenses and other liabilities (15 ) 17 22 Change in fair value of contingent consideration liability — (187 ) (643 ) Tax benefit from stock option exercises and other equity awards 248 496 508 Other, net (195 ) (465 ) (673 ) Net cash provided by operating activities 33,842 31,448 25,855 Cash flows from financing activities: Payment of contingent consideration liability — (1,217 ) — Net proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered 273 (671 ) 366 Cash dividends paid (34,189 ) (29,312 ) (26,300 ) Net cash used in financing activities (33,916 ) (31,200 ) (25,934 ) Net (decrease) increase in cash (74 ) 248 (79 ) Cash at beginning of year 1,912 1,664 1,743 Cash at end of year $1,838 $1,912 $1,664

Selected Quarterly Consolidated

Selected Quarterly Consolidated Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Consolidated Financial Data (Unaudited)	Selected Quarterly Consolidated Financial Data (Unaudited) (Dollars and shares in thousands, except per share amounts) 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $50,194 $50,559 $49,527 $47,383 Interest expense 15,610 16,701 16,549 15,389 Net interest income 34,584 33,858 32,978 31,994 Provision for loan losses 650 525 400 — Net interest income after provision for loan losses 33,934 33,333 32,578 31,994 Noninterest income 15,367 16,753 18,342 16,618 Noninterest expense 26,964 28,151 26,870 28,755 Income before income taxes 22,337 21,935 24,050 19,857 Income tax expense 4,842 4,662 5,236 4,321 Net income $17,495 $17,273 $18,814 $15,536 Net income available to common shareholders $17,461 $17,238 $18,778 $15,502 Weighted average common shares outstanding - basic 17,304 17,330 17,338 17,351 Weighted average common shares outstanding - diluted 17,401 17,405 17,414 17,436 Per share information: Basic earnings per common share $1.01 $0.99 $1.08 $0.89 Diluted earnings per common share $1.00 $0.99 $1.08 $0.89 Cash dividends declared per share $0.47 $0.51 $0.51 $0.51 (Dollars and shares in thousands, except per share amounts) 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $40,440 $43,286 $45,164 $47,517 Interest expense 8,588 10,175 11,715 13,639 Net interest income 31,852 33,111 33,449 33,878 Provision for loan losses — 400 350 800 Net interest income after provision for loan losses 31,852 32,711 33,099 33,078 Noninterest income 15,743 15,993 15,215 15,163 Noninterest expense 27,130 26,288 26,062 26,682 Income before income taxes 20,465 22,416 22,252 21,559 Income tax expense 4,254 4,742 4,741 4,523 Net income $16,211 $17,674 $17,511 $17,036 Net income available to common shareholders $16,173 $17,636 $17,475 $17,004 Weighted average common shares outstanding - basic 17,234 17,272 17,283 17,297 Weighted average common shares outstanding - diluted 17,345 17,387 17,382 17,385 Per share information: Basic earnings per common share $0.94 $1.02 $1.01 $0.98 Diluted earnings per common share $0.93 $1.01 $1.01 $0.98 Cash dividends declared per share $0.43 $0.43 $0.43 $0.47

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Consolidation	Washington Trust Bancorp, Inc. (the “Bancorp”) is a publicly-owned registered bank holding company that has elected to be a financial holding company. The Bancorp’s subsidiaries include The Washington Trust Company, of Westerly (the “Bank”), a Rhode Island chartered commercial bank founded in 1800, and Weston Securities Corporation (“WSC”). Through its subsidiaries, the Bancorp offers a complete product line of financial services including commercial, residential and consumer lending, retail and commercial deposit products, and wealth management services through its offices in Rhode Island, eastern Massachusetts and Connecticut. The consolidated financial statements include the accounts of the Bancorp and its subsidiaries (collectively, the “Corporation” or “Washington Trust”). All intercompany balances and transactions have been eliminated in consolidation.
Basis of Accounting	The Bancorp also owns the common stock of two capital trusts, which have issued trust preferred securities. These capital trusts are variable interest entities in which the Bancorp is not the primary beneficiary and, therefore, are not consolidated. The capital trust’s only assets are junior subordinated debentures issued by the Bancorp, which were acquired by the capital trusts using the proceeds from the issuance of the trust preferred securities and common stock. The Bancorp’s equity interest in the capital trusts, classified in other assets, and the junior subordinated debentures are included in the Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is included in the Consolidated Statements of Income.
Use of Estimates	In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the balance sheet and revenues and expenses for the period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to change are the determination of the allowance for loan losses, the valuation of goodwill and identifiable intangible assets, the assessment of investment securities for impairment and the accounting for defined benefit pension plans.
Cash and Cash Equivalents	Short-term Investments Short-term investments consist of highly liquid investments with a maturity date of three months or less when purchased and are considered to be cash equivalents. The Corporation’s short-term investments may be composed of overnight federal funds sold, securities purchased under resale agreements, money market mutual funds and U.S. Treasury bills. Cash Flows For purposes of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks, and other short-term investments.
Securities	Securities Management determines the appropriate classification of securities at the time of purchase. Investments in debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and carried at amortized cost. Investments not classified as held to maturity are classified as available for sale. Securities available for sale consist of debt securities that are available for sale to respond to changes in market interest rates, liquidity needs, changes in funding sources and other similar factors. These assets are specifically identified and are carried at fair value. Changes in fair value of available for sale securities, net of applicable income taxes, are reported as a separate component of shareholders’ equity. Washington Trust does not have a trading portfolio. Premiums and discounts are amortized and accreted over the term of the securities on a method that approximates the level yield method. The amortization and accretion is included in interest income on securities. Interest income is recognized when earned. Realized gains or losses from sales of securities are recorded on the trade date and are determined using the specific identification method. The fair values of securities may be based on either quoted market prices or third party pricing services. When the fair value of an investment security is less than its amortized cost basis, the Corporation assesses whether the decline in value is other-than-temporary. The Corporation considers whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for impairment, the severity and duration of the impairment, changes in the value subsequent to the reporting date, forecasted performance of the issuer, changes in the dividend or interest payment practices of the issuer, changes in the credit rating of the issuer or the specific security, and the general market condition in the geographic area or industry in which the issuer operates. In determining whether an other-than-temporary impairment has occurred for debt securities, the Corporation compares the present value of cash flows expected to be collected from the security with the amortized cost of the security. If the present value of expected cash flows is less than the amortized cost of the security, then the entire amortized cost of the security will not be recovered; that is, a credit loss exists, and an other-than-temporary impairment shall be considered to have occurred. The credit loss component of an other-than-temporary impairment write-down for debt securities is recorded in earnings while the remaining portion of the impairment loss is recognized, net of tax, in other comprehensive income provided that the Corporation does not intend to sell the underlying debt security and it is more-likely-than-not that the Corporation would not have to sell the debt security prior to recovery of the unrealized loss, which may be to maturity. If the Corporation intended to sell any securities with an unrealized loss or it is more-likely-than-not that the Corporation would be required to sell the investment securities before recovery of their amortized cost basis, then the entire unrealized loss would be recorded in earnings.
Federal Home Loan Bank Stock	Federal Home Loan Bank Stock The Bank is a member of the FHLB. The FHLB is a cooperative that provides services, including funding in the form of advances, to its member banking institutions. As a requirement of membership, the Bank must own a minimum amount of FHLB stock, calculated periodically based primarily on its level of borrowings from the FHLB. No market exists for shares of FHLB stock and therefore, it is carried at cost. FHLB stock may be redeemed at par value five years following termination of FHLB membership, subject to limitations which may be imposed by the FHLB or its regulator, the Federal Housing Finance Board, to maintain capital adequacy of the FHLB. While the Bank currently has no intentions to terminate its FHLB membership, the ability to redeem its investment in FHLB stock would be subject to the conditions imposed by the FHLB. The Bank monitors its investment to determine if impairment exists. Based on the capital adequacy and the liquidity position of the FHLB, management believes there is no impairment related to the carrying amount of FHLB stock included in the Consolidated Balance Sheet as of December 31, 2019 .
Mortgage Loans Held for Sale	Mortgage Loans Held for Sale Residential mortgage loans originated and intended for sale in the secondary market are classified as held for sale. Accounting Standards Codification (“ASC”) 825, “Financial Instruments” allows for the irrevocable option to elect fair value accounting for the initial and subsequent measurement for certain financial assets and liabilities on a contract-by-contract basis that may otherwise not be required to be measured at fair value under other accounting standards. The Corporation has elected the fair value option for mortgage loans held for sale in order to better match changes in fair values of the loans with changes in the fair value of the derivative forward sale commitment contracts used to economically hedge them. Changes in the fair value of mortgage loans held for sale accounted for under the fair value option are recorded in earnings and are partially offset by changes in fair value of forward sale commitments. These changes in fair value are included in mortgage banking revenues. Gains and losses on residential loan sales are recognized at the time of sale and included in mortgage banking revenues. Upfront fees and costs related to mortgage loans held for sale for which the fair value option was elected are recognized in mortgage banking revenues as received / incurred and are not deferred. Commissions received on mortgage loans brokered to various investors are recognized when received and included in mortgage banking revenues.
Loan Servicing Rights	Loan Servicing Rights When mortgage loans held for sale are sold with servicing retained, mortgage servicing right assets are recognized as separate assets. Mortgage servicing rights are originally recorded at fair value. Fair value is based on a valuation model that incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, ancillary income, prepayment speeds, and default rates and losses. Mortgage servicing rights are included in other assets. Mortgage servicing rights are amortized as an offset to mortgage banking revenues over the period of estimated net servicing income. They are periodically evaluated for impairment based on their fair value. Impairment is measured on an aggregated basis by stratifying the rights based on homogeneous characteristics such as note rate and loan type. The fair value is estimated based on the present value of expected cash flows, incorporating assumptions for discount rate, prepayment speed and servicing cost. Any impairment is recognized through a valuation allowance and as a reduction to mortgage banking revenues.
Loans	Loans Portfolio Loans Loans are carried at the principal amount outstanding, adjusted by partial charge-offs and net of unamortized deferred loan origination fees and costs. Interest income is accrued on a level yield basis based upon principal amounts outstanding, except for loans on nonaccrual status. Deferred loan origination fees and costs are amortized as an adjustment to yield over the term of the related loans. For purchased loans, which did not show signs of credit deterioration at the time of purchase, interest income is also accrued on a level yield basis based upon principal amounts outstanding and is then further adjusted by accretion of any discount or amortization of any premium associated with the loans. Nonaccrual Loans Loans, with the exception of certain well-secured loans that are in the process of collection, are placed on nonaccrual status and interest recognition is suspended when such loans are 90 days or more overdue with respect to principal and/or interest, or sooner if considered appropriate by management. Well-secured loans are permitted to remain on accrual status provided that full collection of principal and interest is assured and the loan is in the process of collection. Loans are also placed on nonaccrual status when, in the opinion of management, full collection of principal and interest is doubtful. When loans are placed on nonaccrual status, interest previously accrued but not collected is reversed against current period income. Subsequent interest payments received on nonaccrual loans are applied to the outstanding principal balance of the loan or recognized as interest income depending on management’s assessment of the ultimate collectability of the loan. Loans are removed from nonaccrual status when they have been current as to principal and interest for a period of time, the borrower has demonstrated an ability to comply with repayment terms, and when, in management’s opinion, the loans are considered to be fully collectible. Troubled Debt Restructured Loans Loans are considered to be troubled debt restructurings when the Corporation has granted concessions to a borrower due to the borrower’s financial condition that it otherwise would not have considered. These concessions may include modifications of the terms of the debt such as deferral of payments, extension of maturity, reduction of principal balance, reduction of the stated interest rate other than normal market rate adjustments, or a combination of these concessions. Debt may be bifurcated with separate terms for each tranche of the restructured debt. Restructuring of a loan in lieu of aggressively enforcing the collection of the loan may benefit the Corporation by increasing the ultimate probability of collection. Restructured loans are classified as accruing or non-accruing based on management’s assessment of the collectability of the loan. Loans which are already on nonaccrual status at the time of the restructuring generally remain on nonaccrual status for approximately six months before management considers such loans for return to accruing status. Accruing restructured loans are placed into nonaccrual status if and when the borrower fails to comply with the restructured terms and management deems it unlikely that the borrower will return to a status of compliance in the near term. Troubled debt restructurings are reported as such for at least one year from the date of the restructuring. In years after the restructuring, troubled debt restructured loans are removed from this classification if the restructuring did not involve a below-market rate concession and the loan is not deemed to be impaired based on the terms specified in the restructuring agreement. Impaired Loans A loan is considered impaired when, based on current information and events, it is probable that the Corporation will not be able to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Impaired loans are evaluated on an individual basis and include nonaccrual loans and loans restructured in a troubled debt restructuring.
Allowance for Loan Losses	Allowance for Loan Losses The allowance for loan losses is management’s best estimate of the risk of loss inherent in the loan portfolio as of the balance sheet date. The allowance is increased by provisions charged to earnings and by recoveries of amounts previously charged-off, and is reduced by charge-offs on loans. Loan charge-offs are recognized when management believes the collectability of the principal balance outstanding is unlikely. Full or partial charge-offs on collateral dependent impaired loans are generally recognized when the collateral is deemed to be insufficient to support the carrying value of the loan. The level of the allowance is based on management’s ongoing review of the growth and composition of the loan portfolio, historical loss experience, estimated loss emergence period (the period from the event that triggers the eventual default until the actual loss is recognized with a charge-off), current economic conditions, analysis of asset quality and credit quality levels and trends, the performance of individual loans in relation to contract terms and other pertinent factors. A methodology is used to systematically measure the amount of estimated loan loss exposure inherent in the loan portfolio for the purposes of establishing a sufficient allowance for loan losses. The methodology includes: (1) the identification of loss allocations for individual loans deemed to be impaired and (2) the application of loss allocation factors for non-impaired loans based on historical loss experience and estimated loss emergence period, with adjustments for various exposures that management believes are not adequately represented by historical loss experience. Loss allocations for loans deemed to be impaired are measured using a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or, if the loan is collateral dependent, at the fair value of the collateral. For collateral dependent loans for which repayment is dependent on the sale of the collateral, management adjusts the fair value for estimated costs to sell. For collateral dependent loans for which repayment is dependent on the operation of the collateral, such as accruing troubled debt restructured loans, estimated costs to sell are not incorporated into the measurement. Management may also adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of circumstances associated with the property. For loans that are collectively evaluated, loss allocation factors are derived by analyzing historical loss experience by loan segment over an established look-back period deemed to be relevant to the inherent risk of loss in the portfolios. Loans are segmented by loan type, collateral type, delinquency status and loan risk rating, where applicable. These loss allocation factors are adjusted to reflect the loss emergence period. These amounts are supplemented by certain qualitative risk factors reflecting management’s view of how losses may vary from those represented by historical loss rates. These qualitative risk factors include: 1) changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; 2) changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; 3) changes in the nature and volume of the portfolio and in the terms of loans; 4) changes in the experience, ability, and depth of lending management and other relevant staff; 5) changes in the volume and severity of past due loans, the volume of nonaccrual loans, and the volume and severity of adversely classified or rated loans; 6) changes in the quality of the institution’s loan review system; 7) changes in the value of underlying collateral for collateral dependent loans; 8) the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and 9) the effect of other external factors such as legal and regulatory requirements on the level of estimated credit losses in the institution’s existing portfolio. Because the methodology is based upon historical experience and trends, current economic data, as well as management’s judgment, factors may arise that result in different estimations. Adversely different conditions or assumptions could lead to increases in the allowance. In addition, various regulatory agencies periodically review the allowance for loan losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination. The allowance is an estimate, and ultimate losses may vary from management’s estimate. Changes in the estimate are recorded in the results of operations in the period in which they become known, along with provisions for estimated losses incurred during that period.
Premises and Equipment	Premises and Equipment Land is carried at cost. Premises and equipment are carried at cost less accumulated depreciation. Depreciation for financial reporting purposes is calculated on the straight-line method over the estimated useful lives of assets. Leasehold improvements are depreciated over the shorter of the lease terms or the estimated useful lives of the improvements. Expected terms include lease renewal options to the extent that the exercise of such renewals is reasonably assured. Expenditures for major additions and improvements are capitalized while the costs of current maintenance and repairs are charged to operating expenses. The estimated useful lives of premises and improvements range from 5 to 40 years. For furniture, fixtures and equipment, the estimated useful lives range from 3 to 20 years.
Leases	Leases The Corporation has committed to rent premises used in business operations under non-cancelable operating leases and determines if an arrangement meets the definition of a lease upon inception. Prior to January 1, 2019, operating leases were accounted for under ASC 840, Leases, and were considered off-balance sheet commitments as neither an asset or liability was recognized in the Consolidated Balance Sheets. Effective January 1, 2019, the Corporation adopted the provisions of ASC 842, Leases, as further disclosed in Note 2. ASC 842 requires operating leases to be recorded on the balance sheet, through the recognition of an operating lease right-of-use asset (“ROU”) and an operating lease liability at the commencement date of the new lease. ROU assets represent a right to use an underlying asset for the contractual lease term. Operating lease liabilities represent an obligation to make lease payments arising from the lease. The Corporation’s leases do not provide an implicit interest rate, therefore the Corporation uses its incremental collateralized borrowing rates commensurate with the underlying lease terms to determine the present value of operating lease liabilities. The Corporation’s operating lease agreements contain both lease and non-lease components, which are generally accounted for separately. The Corporation’s lease agreements do not contain any residual value guarantees. Operating leases with terms of 12 months or less are included in ROU assets and operating lease liabilities recorded in the Corporation’s Consolidated Balance Sheets. Operating lease terms include options to extend when it is reasonably certain that the Corporation will exercise such options, determined on a lease-by-lease basis. Under both ASC 840 and ASC 842, rental expense for operating leases is recognized on a straight-line basis over the lease term. Variable lease components, such as consumer price index adjustments, are expensed as incurred and not included in ROU assets and operating lease liabilities.
Goodwill and Identifiable Intangible Assets	Goodwill and Identifiable Intangible Assets Goodwill represents the excess of the purchase price over the net fair value of the acquired businesses. Goodwill is not amortized but is tested for impairment at the reporting unit level, defined as the segment level, at least annually in the fourth quarter or more frequently whenever events or circumstances occur that indicate that it is more-likely-than-not that an impairment loss has occurred. In assessing impairment, the Corporation has the option to perform a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of such events or circumstances, we determine it is not more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, then we would not be required to perform an impairment test. The quantitative impairment analysis requires a comparison of each reporting unit’s fair value to its carrying value to identify potential impairment. Goodwill impairment exists when a reporting unit’s carrying value of goodwill exceeds its implied fair value. Significant judgment is applied when goodwill is assessed for impairment. This judgment includes, but may not be limited to, the selection of appropriate discount rates, the identification of relevant market comparables and the development of cash flow projections. The selection and weighting of the various fair value techniques may result in a higher or lower fair value. Judgment is applied in determining the weightings that are most representative of fair value. Intangible assets identified in acquisitions consist of advisory contracts. The value attributed to intangible assets was based on the time period over which they are expected to generate economic benefits. Intangible assets are amortized over their estimated lives using a method that approximates the amount of economic benefits that are realized by the Corporation. Intangible assets with definite lives are tested for impairment whenever events or circumstances occur that indicate that the carrying amount may not be recoverable. If applicable, the Corporation tests each of the intangibles by comparing the carrying value of the intangible asset to the sum of undiscounted cash flows expected to be generated by the asset. If the carrying amount of the asset exceeds its undiscounted cash flows, then an impairment loss would be recognized for the amount by which the carrying amount exceeds its fair value. Impairment would result in a write-down to the estimated fair value based on the anticipated discounted future cash flows. The remaining useful life of the intangible assets that are being amortized is also evaluated to determine whether events and circumstances warrant a revision to the remaining period of amortization.
Impairment of Long-Lived Assets Other than Goodwill	Impairment of Long - Lived Assets Other than Goodwill Long-lived assets, including premises and equipment, are reviewed for impairment whenever events or changes in business circumstances indicate that the carrying amount may not be fully recoverable. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal.
Property Acquired through Foreclosure or Repossession	Property Acquired through Foreclosure or Repossession Property acquired through foreclosure or repossession is carried at the lower of cost or fair value less estimated costs to sell. Fair value of such assets is determined based on independent appraisals and other relevant factors. Any write-down to fair value at the time of foreclosure or repossession is charged to the allowance for loan losses. Subsequent to foreclosure or repossession, a valuation allowance is maintained for declines in market value and for estimated selling expenses. Upon sale of foreclosed property, any excess of the carrying value over the sales proceeds is recognized as a loss on sale. Any excess of sales proceeds over the carrying value of the foreclosed property is first applied as a recovery to the valuation allowance, if any, with the remainder being recognized as a gain on sale. Changes to the valuation allowance, expenses associated with ownership of these properties, and gains and losses from their sale are included in foreclosed property costs. Loans that are substantively repossessed include only those loans for which the Corporation has obtained control of the collateral, but has not completed legal foreclosure proceedings.
Bank-Owned Life Insurance	Bank-Owned Life Insurance The investment in BOLI represents the cash surrender value of life insurance policies on the lives of certain employees who have provided positive consent allowing the Bank to be the beneficiary of such policies. Increases in the cash value of the policies, as well as insurance proceeds received, are recorded in noninterest income and are not subject to income taxes. The financial strength of the insurance carrier is reviewed prior to the purchase of BOLI and annually thereafter.
Investment in Real Estate Limited Partnerships	Investment in Real Estate Limited Partnerships The Bank has a 99.9% ownership interest in three real estate limited partnerships that renovate, own and operate three low-income housing complexes. The Bank neither actively participates nor has a controlling interest in these limited partnerships. The carrying value of these investments is recorded in other assets on the Consolidated Balance Sheets. Investments made prior to January 1, 2015 are accounted for under the equity method of accounting. Net losses generated by the partnership are recorded as a reduction to the Bank’s investment and as a reduction of other noninterest income in the Consolidated Statements of Income. Tax credits generated by the partnerships are recorded as a reduction in the income tax provision in the year they are allowed for tax reporting purposes. The results of operations of the real estate limited partnerships are periodically reviewed to determine if the partnership generates sufficient operating cash flow to fund its current obligations. In addition, the current value of the underlying properties is compared to the outstanding debt obligations. If it is determined that the investment is permanently impaired, the carrying value would be written down to the estimated realizable value. Investments made after January 1, 2015 are accounted for using the proportional amortization method. Unfunded commitments for future capital contributions are recognized and recorded in other liabilities on the Consolidated Balance Sheets. Under the proportional amortization method, the investment is amortized over the same tax period and in proportion to the total tax benefits expected to be allocated to the Bank. The amortization is recognized as a component of income tax expense in the Consolidated Statements of Income. In addition, operating losses and tax credits generated by the partnership are also recorded as a reduction to income tax expense.
Transfers and Servicing of Assets and Extinguishments of Liabilities	Transfers and Servicing of Assets and Extinguishments of Liabilities The accounting for transfers and servicing of financial assets and extinguishments of liabilities is based on consistent application of a financial components approach that focuses on control. This approach distinguishes transfers of financial assets that are sales from transfers that are secured borrowings. Transfers of financial assets are accounted for as sales when control over the assets has been surrendered. Control over transferred assets is deemed to be surrendered when (1) the assets have been isolated from the Corporation, (2) the transferee obtains the right to pledge or exchange the transferred assets with no conditions that constrain the transferee and provide more than a trivial benefit to the Corporation, and (3) the Corporation does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. If a transfer does not meet the criteria for a sale, the transfer is accounted for as a secured borrowing with a pledge of collateral.
Wealth Management Assets Under Administration	Wealth Management Assets Under Administration Assets under administration represent assets held in a fiduciary or agency capacity for wealth management clients and are not included in the Consolidated Balance Sheets, as these are not assets of the Corporation.
Revenue from Contracts with Customers	Revenue from Contracts with Customers Prior to January 1, 2018, fee revenue such as wealth management revenues and service charges on deposit accounts were recognized when earned or to the extent services were completed. Effective January 1, 2018, the Corporation adopted the provisions of ASC 606, Revenue from Contracts with Customers. ASC 606 provides a revenue recognition framework for contracts with customers unless those contracts are within the scope of other accounting standards. Revenue from contracts with customers is measured based on the consideration specified in the contract with a customer. The Corporation recognizes revenue from contracts with customers when it satisfies its performance obligations. The performance obligations are generally satisfied as services are rendered and can either be satisfied at a point in time or over time. The Corporation recognizes revenue that is transactional in nature and such revenue is earned at a point in time. Revenue that is recognized at a point in time includes card interchange fees (fee income related to debit card transactions), ATM fees, wire transfer fees, overdraft charge fees, and stop-payment and returned check fees. Such revenue is derived from transactional information and is recognized as revenue immediately as the transactions occur or upon providing the service to complete the customer’s transaction. The Corporation recognizes revenue over a period of time, generally monthly, as services are performed and performance obligations are satisfied. Such revenue includes wealth management revenues and service charges on deposit accounts. Wealth management revenues are categorized as either asset-based revenues or transaction-based revenues. Asset-based revenues include trust and investment management fees that are earned based upon a percentage of asset values under administration. Transaction-based revenues include financial planning fees, tax preparation fees, commissions and other service fees. Fee revenue from service charges on deposit accounts represent the service charges assessed to customers who hold deposit accounts at the Bank. In certain cases, other parties are involved with providing services to our customers. If the Corporation is a principal in the transaction (providing services itself or through a third party on its behalf), revenues are reported based on the gross consideration received from the customer and any related expenses are reported gross in noninterest expense. If the Corporation is an agent in the transaction (referring customers to another party to provide services), the Corporation reports its net fee or commission retained as revenue. For certain commissions and incentives, such as those paid to employees in our wealth management services and commercial banking segments in order to obtain customer contracts, contract cost assets are established. The contract cost assets are capitalized and amortized over the estimated useful life that the asset is expected to generate benefits. Contract cost assets are included in other assets in the Consolidated Balance Sheets. The amortization of contract cost assets is recorded within salaries and employee benefits expense in the Consolidated Statements of Income.
Pension Costs	Pension Costs Pension benefits are accounted for using the net periodic benefit cost method, which recognizes the compensation cost of an employee’s pension benefit over that employee’s approximate service period. Pension benefit costs and benefit obligations incorporate various actuarial and other assumptions, including discount rates, mortality, rates of return on plan assets and compensation increases. Management evaluates these assumptions on an annual basis and makes modifications to the assumptions based on current rates and trends when it is appropriate to so do. The effect of modifications to those assumptions is recorded in other comprehensive income (loss) and amortized to net periodic cost over future periods. The service cost component of net periodic benefit cost is recognized within salaries and employee benefits expense in the Consolidated Statements of Income. All other components of net periodic benefit cost are recognized in other noninterest expense in the Consolidated Statements of Income. The funded status of defined benefit pension plans, measured as the difference between the fair value of plan assets and the projected benefit obligation, is recognized in the Consolidated Balance Sheet. The changes in the funded status of the defined benefit plans, including actuarial gains and losses and prior service costs and credits, are recognized in comprehensive income in the year in which the changes occur.
Share-Based Compensation	Share-Based Compensation Share-based compensation plans provide for awards of stock options and other equity incentives, including nonvested share units and nonvested performance share units. Compensation expense for awards is recognized over the service period based on the fair value at the date of grant. Grant date fair value for stock options is estimated using the Black-Scholes option-pricing model. Awards of nonvested share units and nonvested performance share units are valued at the fair market value of the Bancorp’s common stock as of the award date. Nonvested performance share unit compensation expense is based on the most recent performance assumption available and is adjusted as assumptions change. Forfeitures are recognized when they occur. Excess tax benefits (expenses) related to stock option exercises, settlement of other equity awards and dividends paid on nonvested share awards are recorded as a decrease (increase) to income tax expense. Excess tax benefits (expenses) on the settlement of share-based awards are reflected in the Consolidated Statements of Cash Flows as an operating activity.
Income Taxes	Income Taxes Income tax expense is determined based on the asset and liability method, whereby deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. 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. Additionally, a liability for unrecognized tax benefits is recorded for uncertain tax positions taken by the Corporation on its tax returns for which there is less than a 50% likelihood of being recognized upon a tax examination. The Corporation records interest related to unrecognized tax benefits in income tax expense. Penalties, if incurred, would be recognized as a component of income tax expense.
Segment Reporting	Segment Reporting The Corporation segregates financial information in assessing its results among its Commercial Banking and Wealth Management Services operating segments. The amounts in the Corporate unit include activity not related to the segments. The methodologies and organizational hierarchies that define the business segments are periodically reviewed and revised. Results may be restated, when necessary, to reflect changes in organizational structure or allocation methodology. Any changes in estimates and allocations that may affect the reported results of any business segment will not affect the consolidated financial position or results of operations of the Corporation as a whole. Management uses certain methodologies to allocate income and expenses to the business lines. A funds transfer pricing (“FTP”) methodology is used to assign interest income and interest expense to each interest-earning asset and interest-bearing liability on a matched maturity funding basis. The matched maturity funding concept considers the origination date and the earlier of the maturity date or the repricing date of a financial instrument to assign an FTP rate for loans and deposits originated. Loans are assigned a FTP rate for funds used and deposits are assigned a FTP rate for funds provided. Certain indirect expenses are allocated to segments. These include indirect expenses such as technology, operations and other support functions.
Earnings Per Share (EPS)	Earnings Per Common Share (“EPS”) EPS is calculated utilizing the two-class method. The two-class method is an earnings allocation formula that determines earnings per share of each class of stock according to dividends and participation rights in undistributed earnings. Share‑based awards that entitle holders to receive non-forfeitable dividends before vesting are considered participating securities (i.e. nonvested restricted stock units), not subject to performance-based measures. These participating securities are included in the earnings allocation for computing basic earnings per share under this method. Undistributed income is allocated to common shareholders and participating securities under the two-class method based upon the proportion of each to the total weighted average shares available. Under the two-class method, basic earnings per common share is computed by dividing net income available to common shareholders by the weighted-average number of common shares outstanding. Diluted earnings per common share is computed using the weighted-average number of shares determined for the basic earnings per common share computation plus the dilutive effect on common shares outstanding, using the treasury stock method.
Comprehensive Income	Comprehensive Income Comprehensive income is defined as all changes in equity, except for those resulting from transactions with shareholders. Net income is a component of comprehensive income. All other components are referred to in the aggregate as other comprehensive income (loss). Other comprehensive income (loss) includes the after-tax effect of net changes in the fair value of securities available for sale, net changes in fair value of cash flow hedges and net changes in defined benefit pension plan obligations.
Guarantees	Guarantees Standby letters of credit are considered a guarantee of the Corporation. Standby letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. The credit risk involved in issuing standby letters of credit is essentially the same as that involved in extending loan facilities to customers. Under the standby letters of credit, the Corporation is required to make payments to the beneficiary of the letters of credit upon request by the beneficiary contingent upon the customer’s failure to perform under the terms of the underlying contract with the beneficiary.
Derivative Insturments and Hedging Activities	Derivative Instruments and Hedging Activities Derivatives are recognized as either assets or liabilities on the balance sheet and are measured at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative and resulting designation. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivative are recorded in other comprehensive income (loss) and subsequently reclassified to earnings when gains or losses are realized. For derivatives not designated as hedges, changes in fair value of the derivative instruments are recognized in earnings, in noninterest income. The accrued net settlements on derivatives that qualify for hedge accounting are recorded in interest income or interest expense based on the item being hedged. Changes in fair value of derivatives, including accrued net settlements that do not qualify for hedge accounting, are reported in noninterest income. When a cash flow hedge is discontinued, but the hedged cash flows or forecasted transaction is still expected to occur, changes in value that were accumulated in other comprehensive income (loss) are amortized or accreted into earnings over the same periods that the hedged transactions will affect earnings.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820, “Fair Value Measurements and Disclosures”, establishes a framework for measuring fair value and expands disclosures about fair value measurements. The required disclosures about fair value measurements have been included in Note 14 .

Securities (Tables)

Securities (Tables)	12 Months Ended
	Dec. 31, 2019
Gain (Loss) on Securities [Line Items]
Summary of Investments	The following tables present the amortized cost, gross unrealized holding gains, gross unrealized holding losses and fair value of securities by major security type and class of security: (Dollars in thousands) December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $157,255 $626 ($233 ) $157,648 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 713,553 8,491 (2,964 ) 719,080 Individual name issuer trust preferred debt securities 13,324 — (745 ) 12,579 Corporate bonds 11,141 — (958 ) 10,183 Total available for sale debt securities $895,273 $9,117 ($4,900 ) $899,490 Total securities $895,273 $9,117 ($4,900 ) $899,490 (Dollars in thousands) December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $246,708 $442 ($4,467 ) $242,683 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 675,368 1,943 (16,518 ) 660,793 Obligations of states and political subdivisions 935 2 — 937 Individual name issuer trust preferred debt securities 13,307 — (1,535 ) 11,772 Corporate bonds 13,402 — (1,777 ) 11,625 Total available for sale debt securities $949,720 $2,387 ($24,297 ) $927,810 Held to Maturity Debt Securities: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $10,415 $— ($99 ) $10,316 Total held to maturity debt securities 10,415 — (99 ) 10,316 Total securities $960,135 $2,387 ($24,396 ) $938,126
Securities by Contractual Maturity	The schedule of maturities of available for sale debt securities is presented below. Mortgage-backed securities are included based on weighted average maturities, adjusted for anticipated prepayments. All other debt securities are included based on contractual maturities. Actual maturities may differ from amounts presented because certain issuers have the right to call or prepay obligations with or without call or prepayment penalties. (Dollars in thousands) December 31, 2019 Amortized Cost Fair Value Due in one year or less $103,241 $103,962 Due after one year to five years 349,290 351,538 Due after five years to ten years 264,354 264,958 Due after ten years 178,388 179,032 Total securities $895,273 $899,490 Included in the above table are available for sale debt securities with an amortized cost balance of $180.4 million and a fair value of $179.1 million at December 31, 2019 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 4 months to 17 years, with call features ranging from 1 month to 2 years.
Securities in a Continuous Unrealized Loss Position	The following tables summarize temporarily impaired securities, segregated by length of time the securities have been in a continuous unrealized loss position: (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2019 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises 3 $20,364 ($136 ) 3 $49,902 ($97 ) 6 $70,266 ($233 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 4 41,150 (56 ) 23 216,804 (2,908 ) 27 257,954 (2,964 ) Individual name issuer trust preferred debt securities — — — 5 12,579 (745 ) 5 12,579 (745 ) Corporate bonds — — — 3 10,183 (958 ) 3 10,183 (958 ) Total temporarily impaired securities 7 $61,514 ($192 ) 34 $289,468 ($4,708 ) 41 $350,982 ($4,900 ) (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2018 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises — $— $— 16 $157,032 ($4,467 ) 16 $157,032 ($4,467 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 10 47,060 (439 ) 51 438,701 (16,178 ) 61 485,761 (16,617 ) Individual name issuer trust preferred debt securities — — — 5 11,772 (1,535 ) 5 11,772 (1,535 ) Corporate bonds 3 1,198 (9 ) 5 10,427 (1,768 ) 8 11,625 (1,777 ) Total temporarily impaired securities 13 $48,258 ($448 ) 77 $617,932 ($23,948 ) 90 $666,190 ($24,396 )
Schedule of Realized Gain (Loss)	The following table summarizes amounts relating to sales of securities: (Dollars in thousands) For the periods ended December 31, 2019 2018 2017 Proceeds from sales $11,877 $— $— Gross realized gains $— $— $— Gross realized losses (53 ) — — Net realized losses on securities ($53 ) $— $—

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Summary of Loans	The following is a summary of loans: (Dollars in thousands) December 31, 2019 December 31, 2018 Amount % Amount % Commercial: Commercial real estate (1) $1,547,572 40 % $1,392,408 38 % Commercial & industrial (2) 585,289 15 620,704 17 Total commercial 2,132,861 55 2,013,112 55 Residential Real Estate: Residential real estate (3) 1,449,090 37 1,360,387 37 Consumer: Home equity 290,874 7 280,626 8 Other (4) 20,174 1 26,235 — Total consumer 311,048 8 306,861 8 Total loans (5) $3,892,999 100 % $3,680,360 100 % (1) Commercial real estate (“CRE”) consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings. (2) Commercial and industrial (“C&I”) consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (3) Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties. (4) Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 .
Past Due Loans	The following tables present an aging analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due December 31, 2019 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $830 $— $603 $1,433 $1,546,139 $1,547,572 Commercial & industrial 1 — — 1 585,288 585,289 Total commercial 831 — 603 1,434 2,131,427 2,132,861 Residential Real Estate: Residential real estate 4,574 2,155 4,700 11,429 1,437,661 1,449,090 Consumer: Home equity 971 729 996 2,696 288,178 290,874 Other 42 — 88 130 20,044 20,174 Total consumer 1,013 729 1,084 2,826 308,222 311,048 Total loans $6,418 $2,884 $6,387 $15,689 $3,877,310 $3,892,999 (Dollars in thousands) Days Past Due December 31, 2018 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $155 $925 $— $1,080 $1,391,328 $1,392,408 Commercial & industrial — — — — 620,704 620,704 Total commercial 155 925 — 1,080 2,012,032 2,013,112 Residential Real Estate: Residential real estate 6,318 2,693 1,509 10,520 1,349,867 1,360,387 Consumer: Home equity 1,281 156 552 1,989 278,637 280,626 Other 33 — — 33 26,202 26,235 Total consumer 1,314 156 552 2,022 304,839 306,861 Total loans $7,787 $3,774 $2,061 $13,622 $3,666,738 $3,680,360
Impaired Loans	The following is a summary of impaired loans: (Dollars in thousands) Recorded Investment (1) Unpaid Principal Related Allowance December 31, 2019 2018 2019 2018 2019 2018 No Related Allowance Recorded Commercial: Commercial real estate $— $925 $— $926 $— $— Commercial & industrial — 4,681 — 4,732 — — Total commercial — 5,606 — 5,658 — — Residential Real Estate: Residential real estate 13,968 9,347 14,803 9,695 — — Consumer: Home equity 1,471 1,360 1,472 1,360 — — Other 88 — 88 — — — Total consumer 1,559 1,360 1,560 1,360 — — Subtotal 15,527 16,313 16,363 16,713 — — With Related Allowance Recorded Commercial: Commercial real estate 603 — 926 — — — Commercial & industrial 657 52 657 73 580 — Total commercial 1,260 52 1,583 73 580 — Residential Real Estate: Residential real estate 687 364 714 390 95 100 Consumer: Home equity 292 85 291 85 291 24 Other 18 22 18 22 2 3 Total consumer 310 107 309 107 293 27 Subtotal 2,257 523 2,606 570 968 127 Total impaired loans $17,784 $16,836 $18,969 $17,283 $968 $127 Total: Commercial $1,260 $5,658 $1,583 $5,731 $580 $— Residential real estate 14,655 9,711 15,517 10,085 95 100 Consumer 1,869 1,467 1,869 1,467 293 27 Total impaired loans $17,784 $16,836 $18,969 $17,283 $968 $127 (1) The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest. The following table presents the average recorded investment balance of impaired loans and interest income recognized on impaired loans segregated by loan class: (Dollars in thousands) Average Recorded Investment Interest Income Recognized Years ended December 31, 2019 2018 2017 2019 2018 2017 Commercial: Commercial real estate $864 $1,050 $8,425 $1 $— $79 Commercial & industrial 2,149 5,403 6,445 106 259 281 Total commercial 3,013 6,453 14,870 107 259 360 Residential real estate: Residential real estate 11,575 9,645 14,571 473 393 444 Consumer: Home equity 1,466 1,182 685 58 52 31 Other 68 69 143 2 5 10 Total consumer 1,534 1,251 828 60 57 41 Totals $16,122 $17,349 $30,269 $640 $709 $845
Nonaccrual Loans	The following is a summary of nonaccrual loans, segregated by class of loans: (Dollars in thousands) December 31, 2019 2018 Commercial: Commercial real estate $603 $925 Commercial & industrial 657 — Total commercial 1,260 925 Residential Real Estate: Residential real estate 14,297 9,346 Consumer: Home equity 1,763 1,436 Other 88 — Total consumer 1,851 1,436 Total nonaccrual loans $17,408 $11,707 Accruing loans 90 days or more past due $— $—
Credit Quality Indicators - Commercial	The following table presents the commercial loan portfolio, segregated by category of credit quality indicator: (Dollars in thousands) Pass Special Mention Classified December 31, 2019 2018 2019 2018 2019 2018 Commercial: Commercial real estate $1,546,139 $1,387,666 $830 $205 $603 $4,537 Commercial & industrial 549,416 559,019 24,961 50,426 10,912 11,259 Total commercial $2,095,555 $1,946,685 $25,791 $50,631 $11,515 $15,796
Credit Quality Indicators - Residential & Consumer	The following table presents the residential and consumer loan portfolios, segregated by category of credit quality indicator: (Dollars in thousands) Current Past Due December 31, 2019 2018 2019 2018 Residential Real Estate: Residential real estate $1,437,661 $1,349,867 $11,429 $10,520 Consumer: Home equity $288,178 $278,637 $2,696 $1,989 Other 20,044 26,202 130 33 Total consumer $308,222 $304,839 $2,826 $2,022
Analysis of Loan Servicing Rights	The following table presents an analysis of loan servicing rights: (Dollars in thousands) Loan Servicing Rights Valuation Allowance Total Balance at December 31, 2016 $3,493 $— $3,493 Loan servicing rights capitalized 1,104 — 1,104 Amortization (984 ) — (984 ) Balance at December 31, 2017 3,613 — 3,613 Loan servicing rights capitalized 905 — 905 Amortization (867 ) — (867 ) Balance at December 31, 2018 3,651 — 3,651 Loan servicing rights capitalized 902 — 902 Amortization (1,027 ) — (1,027 ) Balance at December 31, 2019 $3,526 $— $3,526
Amortization Expense Related to Loan Servicing Assets	The following table presents estimated aggregate amortization expense related to loan servicing assets: (Dollars in thousands) Years ending December 31: 2020 $825 2021 632 2022 484 2023 371 2024 284 2025 and thereafter 930 Total estimated amortization expense $3,526
Loans Serviced for Others, by Type of Loan	The following table presents the balance of loans serviced for others by type of loan: (Dollars in thousands) December 31, 2019 2018 Residential mortgages $586,996 $588,534 Commercial loans 159,948 142,218 Total $746,944 $730,752

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2019
Receivables [Abstract]
Allowance for Loan Losses Rollforward Analysis	The following table presents the activity in the allowance for loan losses for the year ended December 31, 2019 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $15,381 $5,847 $21,228 $3,987 $1,603 $254 $1,857 $27,072 Charge-offs (1,028 ) (21 ) (1,049 ) (486 ) (390 ) (95 ) (485 ) (2,020 ) Recoveries 125 168 293 — 72 22 94 387 Provision 263 (2,073 ) (1,810 ) 3,114 105 166 271 1,575 Ending Balance $14,741 $3,921 $18,662 $6,615 $1,390 $347 $1,737 $27,014 The following table presents the activity in the allowance for loan losses for the year ended December 31, 2018 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $12,729 $5,580 $18,309 $5,427 $2,412 $340 $2,752 $26,488 Charge-offs (627 ) (10 ) (637 ) (250 ) (193 ) (107 ) (300 ) (1,187 ) Recoveries 25 119 144 21 29 27 56 221 Provision 3,254 158 3,412 (1,211 ) (645 ) (6 ) (651 ) 1,550 Ending Balance $15,381 $5,847 $21,228 $3,987 $1,603 $254 $1,857 $27,072 The following table presents the activity in the allowance for loan losses for the year ended December 31, 2017 : (Dollars in thousands) Commercial Consumer CRE C&I Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $11,166 $6,992 $18,158 $5,252 $1,889 $705 $2,594 $26,004 Charge-offs (1,867 ) (336 ) (2,203 ) (74 ) (79 ) (106 ) (185 ) (2,462 ) Recoveries 82 169 251 39 33 23 56 346 Provision 3,348 (1,245 ) 2,103 210 569 (282 ) 287 2,600 Ending Balance $12,729 $5,580 $18,309 $5,427 $2,412 $340 $2,752 $26,488
Schedule of Allowance for Loan Loss by Segment & Impairment Methodology	The following table presents the Corporation’s loan portfolio and associated allowance for loan losses by portfolio segment and by impairment methodology: (Dollars in thousands) December 31, 2019 December 31, 2018 Related Allowance Related Allowance Loans Loans Loans Individually Evaluated For Impairment Commercial: Commercial real estate $603 $— $925 $— Commercial & industrial 657 580 4,714 — Total commercial 1,260 580 5,639 — Residential Real Estate: Residential real estate 14,654 95 9,710 100 Consumer: Home equity 1,763 291 1,445 24 Other 106 2 22 3 Total consumer 1,869 293 1,467 27 Subtotal 17,783 968 16,816 127 Loans Collectively Evaluated For Impairment Commercial: Commercial real estate 1,546,969 14,741 1,391,483 15,381 Commercial & industrial 584,632 3,341 615,990 5,847 Total commercial 2,131,601 18,082 2,007,473 21,228 Residential Real Estate: Residential real estate 1,434,436 6,520 1,350,677 3,887 Consumer: Home equity 289,111 1,099 279,182 1,579 Other 20,068 345 26,212 251 Total consumer 309,179 1,444 305,394 1,830 Subtotal 3,875,216 26,046 3,663,544 26,945 Total $3,892,999 $27,014 $3,680,360 $27,072

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Summary of Premises and Equipment	The following presents a summary of premises and equipment: (Dollars in thousands) December 31, 2019 2018 Land $5,921 $6,020 Premises and improvements 40,982 40,210 Furniture, fixtures and equipment 24,760 24,798 Total premises and equipment 71,663 71,028 Less accumulated depreciation 42,963 42,023 Total premises and equipment, net $28,700 $29,005

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Carrying Value of Goodwill	The following table presents the carrying value of goodwill at the reporting unit (or business segment) level: (Dollars in thousands) December 31, 2019 2018 Commercial Banking Segment $22,591 $22,591 Wealth Management Services Segment 41,318 41,318 Balance at December 31, 2018 $63,909 $63,909
Schedule of Carrying Value of Other Intangible Assets	The following table presents the components of intangible assets: (Dollars in thousands) December 31, 2019 2018 Gross carrying amount $20,803 $20,803 Accumulated amortization 13,585 12,641 Net amount $7,218 $8,162
Schedule of Estimated Annual Amortization Expense	The following table presents estimated annual amortization expense for intangible assets at December 31, 2019 : (Dollars in thousands) Years ending December 31, 2020 $914 2021 890 2022 860 2023 843 2024 826 2025 and thereafter 2,885

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense	The following table presents the components of income tax expense: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Current tax expense: Federal $17,298 $15,460 $23,827 State 3,254 2,863 2,201 Total current tax expense 20,552 18,323 26,028 Deferred tax (benefit) expense: Federal (1,294 ) 63 5,717 State (197 ) (126 ) (30 ) Total deferred (benefit) tax expense (1,491 ) (63 ) 5,687 Total income tax expense $19,061 $18,260 $31,715
Schedule of Effective Income Tax Rate Reconciliation	Total income tax expense varies from the amount determined by applying the Federal income tax rate to income before income taxes. The following table presents the reasons for the differences: Years ended December 31, 2019 2018 2017 (Dollars in thousands) Amount Rate Amount Rate Amount Rate Tax expense at Federal statutory rate $18,518 21.0 % $18,205 21.0 % $27,174 35.0 % (Decrease) increase in taxes resulting from: Tax-exempt income, net (814 ) (0.9 ) (809 ) (0.9 ) (1,313 ) (1.7 ) Dividends received deduction (36 ) — (45 ) (0.1 ) (55 ) (0.1 ) BOLI (494 ) (0.6 ) (461 ) (0.5 ) (757 ) (0.9 ) Share-based compensation (221 ) (0.3 ) (444 ) (0.5 ) (481 ) (0.6 ) Federal tax credits (364 ) (0.4 ) (364 ) (0.4 ) (364 ) (0.5 ) Change in fair value of contingent consideration — — (39 ) (0.1 ) (225 ) (0.3 ) State income tax expense, net of federal tax benefit 2,417 2.7 2,162 2.5 1,411 1.8 Adjustment to net deferred tax assets for enacted changes in federal tax law — — — — 6,170 7.9 Other 55 0.1 55 0.1 155 0.2 Total income tax expense $19,061 21.6 % $18,260 21.1 % $31,715 40.8 %
Schedule of Deferred Tax Assets and Liabilities	The following table presents the approximate tax effects of temporary differences that give rise to deferred tax assets and deferred tax liabilities: (Dollars in thousands) December 31, 2019 2018 Deferred tax assets: Allowance for loan losses $6,348 $6,362 Operating lease liabilities 6,782 — Defined benefit pension obligations 1,361 420 Deferred compensation 4,200 3,688 Deferred loan origination fees 1,505 1,410 Share-based compensation 1,358 1,124 Net unrealized losses on available for sale debt securities — 5,149 Other 2,031 1,917 Deferred tax assets 23,585 20,070 Deferred tax liabilities: Net unrealized gains on available for sale debt securities (991 ) — Amortization of intangibles (1,696 ) (1,918 ) Operating lease right-of-use assets (6,296 ) — Deferred loan origination costs (4,084 ) (3,897 ) Loan servicing rights (829 ) (858 ) Other (1,388 ) (1,120 ) Deferred tax liabilities (15,284 ) (7,793 ) Net deferred tax asset $8,301 $12,277

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2019
Deposits [Abstract]
Summary of Deposits	The following table presents a summary of deposits: (Dollars in thousands) December 31, 2019 2018 Noninterest-bearing demand deposits $609,924 $603,216 Interest-bearing demand deposits 159,938 178,733 NOW accounts 520,295 466,568 Money market accounts 765,899 646,878 Savings accounts 373,503 373,545 Time deposits (1) 1,069,323 1,255,108 Total deposits $3,498,882 $3,524,048 (1) Includes wholesale brokered time deposits.
Schedule of Time Certificates of Deposit Maturities	The following table presents scheduled maturities of time certificates of deposit: (Dollars in thousands) Scheduled Maturity Weighted Average Rate Years ending December 31: 2020 $751,525 1.95 % 2021 161,034 2.27 2022 105,846 2.42 2023 32,462 2.04 2024 18,326 1.58 2025 and thereafter 130 2.26 Balance at December 31, 2019 $1,069,323 2.04 %
Schedule of Time Certificates of Deposit $100 Thousand or More Maturities	The following table presents the amount of time certificates of deposit in denominations of $100 thousand or more at December 31, 2019 , maturing during the periods indicated: (Dollars in thousands) January 1, 2020 to March 31, 2020 $57,864 April 1, 2020 to June 30, 2020 106,574 July 1, 2020 to December 31, 2020 115,505 January 1, 2021 and beyond 175,831 Balance at December 31, 2019 $455,774

Borrowings (Tables)

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
FHLB Advances Maturity Summary	The following table presents maturities and weighted average interest rates on FHLB advances outstanding as of December 31, 2019 : (Dollars in thousands) Scheduled Weighted 2020 $974,033 2.07 % 2021 77,222 2.52 2022 813 5.12 2023 5,238 3.80 2024 40,900 2.51 2025 and thereafter 43,258 3.29 Total $1,141,464 2.17 %
Schedule of Short-Term FHLB Advances	The following table presents certain information concerning short-term FHLB advances: (Dollars in thousands) As of and for the years ended December 31, 2019 2018 2017 Average amount outstanding during the period $718,722 $484,090 $351,692 Amount outstanding at end of period 897,000 630,000 367,500 Highest month end balance during period 897,000 630,000 417,500 Weighted-average interest rate at end of period 2.06 % 2.67 % 1.57 % Weighted-average interest rate during the period 2.59 2.23 1.20

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Regulatory Capital Requirements	The following table presents the Corporation’s and the Bank’s actual capital amounts and ratios, as well as the corresponding minimum and well capitalized regulatory amounts and ratios that were in effect during the respective periods: (Dollars in thousands) Actual For Capital Adequacy Purposes To Be “Well Capitalized” Under Prompt Corrective Action Regulations Amount Ratio Amount Ratio Amount Ratio December 31, 2019 Total Capital (to Risk-Weighted Assets): Corporation $494,603 12.94 % $305,728 8.00 % N/A N/A Bank 490,993 12.85 305,693 8.00 $382,116 10.00 % Tier 1 Capital (to Risk-Weighted Assets): Corporation 467,296 12.23 229,296 6.00 N/A N/A Bank 463,686 12.13 229,270 6.00 305,693 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 445,298 11.65 171,972 4.50 N/A N/A Bank 463,686 12.13 171,952 4.50 248,375 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 467,296 9.04 206,682 4.00 N/A N/A Bank 463,686 8.98 206,596 4.00 258,245 5.00 December 31, 2018 Total Capital (to Risk-Weighted Assets): Corporation 455,699 12.56 290,146 8.00 N/A N/A Bank 453,033 12.49 290,128 8.00 362,660 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 428,338 11.81 217,609 6.00 N/A N/A Bank 425,672 11.74 217,596 6.00 290,128 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 406,340 11.20 163,207 4.50 N/A N/A Bank 425,672 11.74 163,197 4.50 235,729 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 428,338 8.89 192,690 4.00 N/A N/A Bank 425,672 8.84 192,652 4.00 240,815 5.00 (1) Leverage ratio.

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivatives by Balance Sheet Location	The following table presents the fair values of derivative instruments in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet Location Dec 31, Dec 31, Balance Sheet Location Dec 31, Dec 31, Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps Other assets $— $20 Other liabilities $— $— Interest rate swaps Other assets — 903 Other liabilities 730 — Interest rate floors Other assets 3 37 Other liabilities — — Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Other assets 27,736 5,340 Other liabilities 358 7,719 Mirror swaps with counterparties Other assets 351 7,592 Other liabilities 27,819 5,392 Risk participation agreements Other assets 1 — Other liabilities 1 — Foreign exchange contracts Other assets — — Other liabilities — 7 Mortgage loan commitments: Interest rate lock commitments Other assets 1,097 806 Other liabilities — — Forward sale commitments Other assets 30 — Other liabilities 827 816 Gross amounts 29,218 14,698 29,735 13,934 Less amounts offset in Consolidated Balance Sheets (1) 354 10,732 354 10,732 Net amounts presented in Consolidated Balance Sheets 28,864 3,966 29,381 3,202 Less collateral pledged (2) — — 27,105 1,460 Net amounts $28,864 $3,966 $2,276 $1,742 (1) Interest rate risk management contracts and loan related derivative contracts with counterparties are subject to master netting arrangements. (2) Collateral pledged to derivative counterparties is in the form of cash. Washington Trust may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions.
Derivative Instruments Effect in Statements of Income and Changes in Shareholders' Equity	The following tables present the effect of derivative instruments in the Corporation’s Consolidated Statements of Changes in Shareholders’ Equity and Consolidated Statements of Income: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax Years ended December 31, 2019 2018 2017 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps $52 $30 ($64 ) Interest rate swaps (1,232 ) 515 358 Interest rate floors 196 74 (346 ) Total ($984 ) $619 ($52 ) (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivatives Years ended December 31, Statement of Income Location 2019 2018 2017 Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income $29,910 ($290 ) $2,243 Mirror swaps with counterparties Loan related derivative income (26,043 ) 2,709 1,198 Risk participation agreements Loan related derivative income 97 (27 ) (233 ) Foreign exchange contracts Loan related derivative income 28 69 6 Mortgage loan commitments: Interest rate lock commitments Mortgage banking revenues 290 (139 ) (100 ) Forward sale commitments Mortgage banking revenues (1,818 ) 997 (328 ) Total $2,464 $3,319 $2,786

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair value of Mortgage Loans Held for Sale	The following table presents a summary of mortgage loans held for sale accounted for under the fair value option: (Dollars in thousands) December 31, 2019 2018 Aggregate fair value $27,833 $20,996 Aggregate principal balance 27,168 20,498 Difference between fair value and principal balance $665 $498
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present the balances of assets and liabilities reported at fair value on a recurring basis: (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2019 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $157,648 $— $157,648 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 719,080 — 719,080 — Individual name issuer trust preferred debt securities 12,579 — 12,579 — Corporate bonds 10,183 — 10,183 — Mortgage loans held for sale 27,833 — 27,833 — Derivative assets 28,864 — 28,864 — Total assets at fair value on a recurring basis $956,187 $— $956,187 $— Liabilities: Derivative liabilities $29,381 $— $29,381 $— Total liabilities at fair value on a recurring basis $29,381 $— $29,381 $— (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2018 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $242,683 $— $242,683 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 660,793 — 660,793 — Obligations of states and political subdivisions 937 — 937 — Individual name issuer trust preferred debt securities 11,772 — 11,772 — Corporate bonds 11,625 — 11,625 — Mortgage loans held for sale 20,996 — 20,996 — Derivative assets 3,966 — 3,966 — Total assets at fair value on a recurring basis $952,772 $— $952,772 $— Liabilities: Derivative liabilities $3,202 $— $3,202 $— Total liabilities at fair value on a recurring basis $3,202 $— $3,202 $—
Fair Value of Contingent Consideration Rollforward	The following table presents the change in the contingent consideration liability, which is included in other liabilities in the Consolidated Balance Sheets. (Dollars in thousands) Years ended December 31, 2019 2018 Beginning Balance $— $1,404 Change in fair value — (187 ) Payments — (1,217 ) Ending Balance $— $—
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis	The following table presents the carrying value of assets held at December 31, 2019 , which were written down to fair value during the year ended December 31, 2019 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $1,448 $— $— $1,448 Property acquired through foreclosure or repossession 1,109 — — 1,109 Total assets at fair value on a nonrecurring basis $2,557 $— $— $2,557 The allowance for loan losses on collateral dependent impaired loans amounted to $871 thousand at December 31, 2019 . In 2019 , a write-down valuation adjustment of $1.0 million on property acquired through foreclosure or repossession was recognized and included in other noninterest expenses in the Consolidated Statements of Income. The following table presents the carrying value of assets held at December 31, 2018 , which were written down to fair value during the year ended December 31, 2018 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $883 $— $— $883 Property acquired through foreclosure or repossession 2,142 — — 2,142 Total assets at fair value on a nonrecurring basis $3,025 $— $— $3,025 The allowance for loan losses on collateral dependent impaired loans amounted to $24 thousand at December 31, 2018 . In 2018 , a write-down valuation adjustment of $1.0 million on property acquired through foreclosure or repossession was recognized and included in other noninterest expenses in the Consolidated Statements of Income.
Qualitative Information About Level 3 Assets Measured at Fair Value on a Nonrecurring Basis	The following tables present valuation techniques and unobservable inputs for assets measured at fair value on a nonrecurring basis for which the Corporation has utilized Level 3 inputs to determine fair value: (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2019 Collateral dependent impaired loans $1,448 Appraisals of collateral Discount for costs to sell 0% - 20% (5%) Appraisal adjustments (1) 0% - 100% (67%) Property acquired through foreclosure or repossession 1,109 Appraisals of collateral Discount for costs to sell 12% Appraisal adjustments (1) 22% (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property. (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2018 Collateral dependent impaired loans $883 Appraisals of collateral Discount for costs to sell 0% - 10% (10%) Appraisal adjustments (1) 0% - 100% (2%) Property acquired through foreclosure or repossession 2,142 Appraisals of collateral Discount for costs to sell 13% Appraisal adjustments (1) 12% - 28% (20%) (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property.
Carrying Amounts, Estimated Fair Values and Fair Value Hierarchy of Financial Instruments	The estimated fair values and related carrying amounts for financial instruments for which fair value is only disclosed are presented below as of the periods indicated. The tables exclude financial instruments for which the carrying value approximates fair value such as cash and cash equivalents, FHLB stock, accrued interest receivable, bank-owned life insurance, non-maturity deposits and accrued interest payable. (Dollars in thousands) Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2019 Financial Assets: Loans, net of allowance for loan losses $3,865,985 $3,869,192 $— $— $3,869,192 Financial Liabilities: Time deposits $1,069,323 $1,082,830 $— $1,082,830 $— FHLB advances 1,141,464 1,145,242 — 1,145,242 — Junior subordinated debentures 22,681 19,628 — 19,628 — (Dollars in thousands) Carrying Amount Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2018 Financial Assets: Held to maturity debt securities $10,415 $10,316 $— $10,316 $— Loans, net of allowance for loan losses 3,653,288 3,598,025 — — 3,598,025 Financial Liabilities: Time deposits $1,255,108 $1,269,433 $— $1,269,433 $— FHLB advances 950,722 950,691 — 950,691 — Junior subordinated debentures 22,681 19,226 — 19,226 —

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Disaggregation of Revenue	The following table summarizes total revenues as presented in the Consolidated Statements of Income and the related amounts which are from contracts with customers within the scope of ASC 606. As shown below, a substantial portion of our revenues are specifically excluded from the scope of ASC 606. Years ended December 31, 2019 2018 2017 (Dollars in thousands) Revenue (1) ASC 606 Revenue (2) Revenue (1) ASC 606 Revenue (2) Revenue (1) ASC 606 Revenue (2) Net interest income $133,414 $— $132,290 $— $119,531 $— Noninterest income: Asset-based wealth management revenues 35,806 35,806 37,343 37,343 38,125 38,125 Transaction-based wealth management revenues 1,042 1,042 998 998 1,221 1,221 Total wealth management revenues 36,848 36,848 38,341 38,341 39,346 39,346 Mortgage banking revenues 14,795 — 10,381 — 11,392 — Card interchange fees 4,214 4,214 3,768 3,768 3,502 3,502 Service charges on deposit accounts 3,684 3,684 3,628 3,628 3,672 3,672 Loan related derivative income 3,993 — 2,461 — 3,214 — Income from bank-owned life insurance 2,354 — 2,196 — 2,161 — Net realized losses on securities (53 ) — — — — — Other income 1,245 1,184 1,339 1,329 1,522 1,469 Total noninterest income 67,080 45,930 62,114 47,066 64,809 47,989 Total revenues $200,494 $45,930 $194,404 $47,066 $184,340 $47,989 (1) As reported in the Consolidated Statements of Income. (2) Revenue from contracts with customers in scope of ASC 606. The following table presents revenue from contracts with customers based on the timing of revenue recognition: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Revenue recognized at a point in time: Card interchange fees $4,214 $3,768 $3,502 Service charges on deposit accounts 2,850 2,802 2,899 Other income 989 958 1,122 Revenue recognized over time: Wealth management revenues 36,848 38,341 39,346 Service charges on deposit accounts 834 826 773 Other income 195 371 347 Total revenues from contracts in scope of ASC 606 $45,930 $47,066 $47,989

Employee Benefits (Tables)

Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2019
Retirement Benefits [Abstract]
Schedule of Projected Benefit Obligations, Fair Value of Plan Assets and Funded (Unfunded) Status	The following table presents the plans’ projected benefit obligations, fair value of plan assets and funded (unfunded) status: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2019 2018 2019 2018 Change in Benefit Obligation: Benefit obligation at beginning of period $73,380 $80,723 $14,626 $15,203 Service cost 2,037 2,244 126 108 Interest cost 2,967 2,715 563 475 Actuarial loss (gain) 10,453 (7,830 ) 2,028 (252 ) Benefits paid (5,546 ) (4,344 ) (905 ) (908 ) Administrative expenses (150 ) (128 ) — — Benefit obligation at end of period 83,141 73,380 16,438 14,626 Change in Plan Assets: Fair value of plan assets at beginning of period 86,180 87,364 — — Actual return on plan assets 13,265 288 — — Employer contributions — 3,000 905 908 Benefits paid (5,546 ) (4,344 ) (905 ) (908 ) Administrative expenses (150 ) (128 ) — — Fair value of plan assets at end of period 93,749 86,180 — — Funded (unfunded) status at end of period $10,608 $12,800 ($16,438 ) ($14,626 )
Schedule of Components of Accumulated Other Comprehensive Income (Loss) Related to Retirements Plans	The following table presents components of accumulated other comprehensive income related to the qualified pension plan and non-qualified retirement plans, on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2019 2018 2019 2018 Net actuarial loss $10,343 $9,453 $7,405 $5,785 Prior service credit — (16 ) — — Total pre-tax amounts recognized in accumulated other comprehensive income $10,343 $9,437 $7,405 $5,785
Schedule of Net Periodic Benefit Costs and Other Amounts Recognized in Other Comprehensive Income (Loss)	The following table presents components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss), on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ended December 31, 2019 2018 2017 2019 2018 2017 Net Periodic Benefit Cost: Service cost (1) $2,037 $2,244 $2,149 $126 $108 $129 Interest cost (2) 2,967 2,715 2,673 563 475 428 Expected return on plan assets (2) (4,495 ) (5,272 ) (4,942 ) — — — Amortization of prior service credit (2) (16 ) (23 ) (23 ) — (1 ) (1 ) Recognized net actuarial loss (2) 792 1,496 1,114 408 411 347 Net periodic benefit cost 1,285 1,160 971 1,097 993 903 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (on a pre-tax basis): Net loss (gain) 890 (4,342 ) (1,798 ) 1,620 (663 ) 1,928 Prior service credit 16 23 23 — 1 1 Recognized in other comprehensive income (loss) 906 (4,319 ) (1,775 ) 1,620 (662 ) 1,929 Total recognized in net periodic benefit cost and other comprehensive income (loss) $2,191 ($3,159 ) ($804 ) $2,717 $331 $2,832 (1) Included in salaries and employee benefits expense in the Consolidated Statements of Income. (2) Included in other expenses in the Consolidated Statements of Income.
Schedule of Assumptions Used for Net Periodic Benefit Cost	The following table presents the measurement date and weighted-average assumptions used to determine benefit obligations at December 31, 2019 and 2018 : Qualified Pension Plan Non-Qualified Retirement Plans 2019 2018 2019 2018 Measurement date Dec 31, 2019 Dec 31, 2018 Dec 31, 2019 Dec 31, 2018 Discount rate 3.42 % 4.38 % 3.30 % 4.30 % Rate of compensation increase 3.75 3.75 3.75 3.75 The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31, 2019 , 2018 and 2017 : Qualified Pension Plan Non-Qualified Retirement Plans 2019 2018 2017 2019 2018 2017 Measurement date Dec 31, 2018 Dec 31, 2017 Dec 31, 2016 Dec 31, 2018 Dec 31, 2017 Dec 31, 2016 Equivalent single discount rate for benefit obligations 4.38 % 3.69 % 4.18 % 4.28 % 3.58 % 3.96 % Equivalent single discount rate for service cost 4.44 3.76 4.29 4.48 3.79 4.25 Equivalent single discount rate for interest cost 4.12 3.42 3.73 3.98 3.22 3.36 Expected long-term return on plan assets 5.75 6.75 6.75 N/A N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75 3.75 3.75
Schedule of Fair Value and Allocation of Plan Assets	The following table presents the asset allocations of the qualified pension plan, by asset category: December 31, 2019 2018 Asset Category: Cash and cash equivalents 10.6 % 30.2 % Fixed income securities 44.4 40.3 Equity securities 45.0 29.5 Total 100.0 % 100.0 % The following tables present the fair values of the qualified pension plan’s assets: (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2019 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $9,902 $— $— $9,902 Obligations of U.S. government-sponsored enterprises — 28,615 — 28,615 Obligations of states and political subdivisions — 2,998 — 2,998 Corporate bonds — 10,033 — 10,033 Common stocks 14,593 — — 14,593 Mutual funds 27,608 — — 27,608 Total plan assets $52,103 $41,646 $— $93,749 (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2018 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $25,986 $— $— $25,986 Obligations of U.S. government-sponsored enterprises — 21,787 — 21,787 Obligations of states and political subdivisions — 2,597 — 2,597 Corporate bonds — 10,361 — 10,361 Common stocks 9,957 — — 9,957 Mutual funds 15,492 — — 15,492 Total plan assets $51,435 $34,745 $— $86,180
Schedule of Expected Future Benefit Payments	The following table presents the benefit payments, which reflect expected future service, as appropriate, expected to be paid: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ending December 31, 2020 $4,748 $898 2021 3,803 887 2022 4,083 878 2023 4,574 876 2024 4,588 871 2025 and thereafter 27,957 4,343

Share-Based Compensation Arra_2

Share-Based Compensation Arrangements (Tables)	12 Months Ended
	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Compensation Cost for Share-based Compensation Arrangements	The following table presents share-based compensation expense and the related income tax benefits recognized in the Consolidated Statements of Income for stock options, nonvested share units and nonvested performance share units: (Dollars in thousands) Years ended December 31, 2019 2018 2017 Share-based compensation expense $3,124 $2,602 $2,577 Related income tax benefits (1) $982 $1,108 $1,114 (1) Includes $248 thousand , $496 thousand , and $508 thousand , respectively, of excess tax benefits recognized upon the settlement of share-based compensation awards in 2019 , 2018 and 2017 .
Stock Options Fair Value Assumptions	The following presents the assumptions used in determining the grant date fair value of the stock option awards granted to certain key employees: 2019 2018 2017 Options granted 61,800 47,950 47,725 Cliff vesting period (years) 3 3 3 Expected term (years) 6.5 6.5 7.0 Expected dividend yield 3.40 % 3.39 % 3.57 % Weighted average expected volatility 23.05 % 22.73 % 27.10 % Weighted average risk-free interest rate 1.71 % 3.14 % 1.70 % Weighted average grant-date fair value $7.44 $9.74 $10.60
Stock Options Activity	The following table presents a summary of the status of Washington Trust’s stock options outstanding as of and for the year ended December 31, 2019 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (000’s) Beginning of period 222,615 $42.92 Granted 61,800 48.65 Exercised (35,600 ) 35.70 Forfeited or expired — — End of period 248,815 $45.38 7.27 $2,308 At end of period: Options exercisable 95,240 $33.57 4.71 $1,926 Options expected to vest in future periods 153,575 $52.70 8.85 $382
Schedule of Stock Options Outstanding and Options Exercisable	The following table presents additional information concerning options outstanding and options exercisable at December 31, 2019 : Options Outstanding Options Exercisable Exercise Price Ranges Number of Shares Weighted Average Remaining Life (Years) Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $15.01 to $20.00 4,100 0.42 $17.52 4,100 $17.52 $20.01 to $25.00 22,015 2.14 22.89 22,015 22.89 $25.01 to $30.00 — — — — — $30.01 to $35.00 19,775 4.16 32.76 19,775 32.76 $35.01 to $40.00 22,100 5.72 39.22 18,100 39.55 $40.01 to $45.00 31,250 6.80 40.25 31,250 40.25 $45.01 to $50.00 61,800 9.80 48.65 — — $50.01 to $55.00 47,950 8.80 54.74 — — $55.01 to $60.00 39,825 7.80 58.05 — — 248,815 7.27 $45.38 95,240 $33.57
Nonvested Shares Units Activity	The following table presents a summary of the status of Washington Trust’s nonvested share units as of and for the year ended December 31, 2019 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 45,350 $48.73 Granted 26,070 49.81 Vested (17,530 ) 40.26 Forfeited — — End of period 53,890 $52.01
Performance Share Units Outstanding	The following table presents a summary of the performance share unit awards as of December 31, 2019 : Grant Date Fair Value per Share Weighted Average Current Performance Assumption Expected Number of Shares Performance share units awarded in: 2019 $52.84 138% 43,360 2018 54.25 140% 41,454 2017 51.85 150% 24,150 Total 108,964
Performance Share Units Activity	The following table presents a summary of the status of Washington Trust’s performance share units as of and for the year ended December 31, 2019 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 93,604 $48.20 Granted 43,360 52.84 Vested (28,239 ) 36.11 Forfeited 239 36.11 End of period 108,964 $53.16

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Statement of Operations and Total Assets by Reportable Segment	The following tables present the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Year ended December 31, 2019 Commercial Wealth Corporate Consolidated Net interest income (expense) $112,414 ($438 ) $21,438 $133,414 Provision for loan losses 1,575 — — 1,575 Net interest income (expense) after provision for loan losses 110,839 (438 ) 21,438 131,839 Noninterest income 27,857 36,856 2,367 67,080 Noninterest expenses: Depreciation and amortization expense 2,630 1,445 159 4,234 Other noninterest expenses 66,517 26,057 13,932 106,506 Total noninterest expenses 69,147 27,502 14,091 110,740 Income before income taxes 69,549 8,916 9,714 88,179 Income tax expense 15,189 2,308 1,564 19,061 Net income $54,360 $6,608 $8,150 $69,118 Total assets at period end $4,070,594 $74,990 $1,147,075 $5,292,659 Expenditures for long-lived assets 2,521 445 166 3,132 (Dollars in thousands) Year ended December 31, 2018 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $106,668 ($334 ) $25,956 $132,290 Provision for loan losses 1,550 — — 1,550 Net interest income (expense) after provision for loan losses 105,118 (334 ) 25,956 130,740 Noninterest income 21,509 38,341 2,264 62,114 Noninterest expenses: Depreciation and amortization expense 2,589 1,501 171 4,261 Other noninterest expenses 62,673 26,222 13,006 101,901 Total noninterest expenses 65,262 27,723 13,177 106,162 Income before income taxes 61,365 10,284 15,043 86,692 Income tax expense 13,149 2,577 2,534 18,260 Net income $48,216 $7,707 $12,509 $68,432 Total assets at period end $3,804,021 $71,254 $1,135,491 $5,010,766 Expenditures for long-lived assets 3,415 407 152 3,974 (Dollars in thousands) Year ended December 31, 2017 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $98,736 ($167 ) $20,962 $119,531 Provision for loan losses 2,600 — — 2,600 Net interest income (expense) after provision for loan losses 96,136 (167 ) 20,962 116,931 Noninterest income 23,244 39,346 2,219 64,809 Noninterest expenses: Depreciation and amortization expense 2,604 1,689 196 4,489 Other noninterest expenses 60,828 26,718 12,065 99,611 Total noninterest expenses 63,432 28,407 12,261 104,100 Income before income taxes 55,948 10,772 10,920 77,640 Income tax expense 23,876 3,795 4,044 31,715 Net income $32,072 $6,977 $6,876 $45,925 Total assets at period end $3,491,845 $66,083 $971,922 $4,529,850 Expenditures for long-lived assets 2,224 360 195 2,779

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Activity in Other Comprehensive Income (Loss)	The following tables present the activity in other comprehensive income (loss): (Dollars in thousands) Year ended December 31, 2019 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $26,074 $6,127 $19,947 Net losses on securities reclassified into earnings (1) 53 12 41 Net change in fair value of available for sale debt securities 26,127 6,139 19,988 Cash flow hedges: Changes in fair value of cash flow hedges (1,444 ) (339 ) (1,105 ) Net cash flow hedge losses reclassified into earnings (2) 159 38 121 Net change in the fair value of cash flow hedges (1,285 ) (301 ) (984 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (3,710 ) (872 ) (2,838 ) Amortization of net actuarial losses (3) 1,200 282 918 Amortization of net prior service credits (3) (16 ) (4 ) (12 ) Net change in defined benefit plan obligations (2,526 ) (594 ) (1,932 ) Total other comprehensive income $22,316 $5,244 $17,072 (1) The pre-tax amount is reported as net realized losses on securities in the Consolidated Statements of Income. (2) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2018 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities ($12,063 ) ($2,835 ) ($9,228 ) Net (gains) losses on securities reclassified into earnings — — — Net change in fair value of available for sale debt securities (12,063 ) (2,835 ) (9,228 ) Cash flow hedges: Changes in fair value of cash flow hedges 639 151 488 Net cash flow hedge losses reclassified into earnings (1) 170 39 131 Net change in the fair value of cash flow hedges 809 190 619 Defined benefit plan obligations: Defined benefit plan obligation adjustment 3,098 729 2,369 Amortization of net actuarial losses (2) 1,907 448 1,459 Amortization of net prior service credits (2) (24 ) (6 ) (18 ) Net change in defined benefit plan obligations 4,981 1,171 3,810 Total other comprehensive loss ($6,273 ) ($1,474 ) ($4,799 ) (1) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (2) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2017 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $986 $365 $621 Net (gains) losses on securities reclassified into earnings — — — Net change in fair value of available for sale debt securities 986 365 621 Cash flow hedges: Changes in fair value of cash flow hedges (774 ) (223 ) (551 ) Net cash flow hedge losses reclassified into earnings (1) 792 293 499 Net change in the fair value of cash flow hedges 18 70 (52 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (1,591 ) (594 ) (997 ) Amortization of net actuarial losses (2) 1,461 546 915 Amortization of net prior service credits (2) (24 ) (9 ) (15 ) Net change in defined benefit plan obligations (154 ) (57 ) (97 ) Total other comprehensive income $850 $378 $472 (1) The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income. (2) The pre-tax amounts are included in other expenses in the Consolidated Statements of Income.
Changes in Components of Accumulated Other Comprehensive Income (Loss)	The following tables present the changes in accumulated other comprehensive income (loss) by component, net of tax: (Dollars in thousands) Net Unrealized (Losses) Gains on Available For Sale Debt Securities Net Unrealized Gains (Losses) on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2018 ($16,762 ) $191 ($11,738 ) ($28,309 ) Other comprehensive income (loss) before reclassifications 19,947 (1,105 ) (2,838 ) 16,004 Amounts reclassified from accumulated other comprehensive income 41 121 906 1,068 Net other comprehensive income (loss) 19,988 (984 ) (1,932 ) 17,072 Balance at December 31, 2019 $3,226 ($793 ) ($13,670 ) ($11,237 ) (Dollars in thousands) Net Unrealized Losses on Available For Sale Debt Securities Net Unrealized (Losses) Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2017 ($7,534 ) ($428 ) ($15,548 ) ($23,510 ) Other comprehensive (loss) income before reclassifications (9,228 ) 488 2,369 (6,371 ) Amounts reclassified from accumulated other comprehensive income — 131 1,441 1,572 Net other comprehensive (loss) income (9,228 ) 619 3,810 (4,799 ) Balance at December 31, 2018 ($16,762 ) $191 ($11,738 ) ($28,309 ) (Dollars in thousands) Net Unrealized (Losses) Gains on Available For Sale Debt Securities Net Unrealized Losses on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total Balance at December 31, 2016 ($6,825 ) ($300 ) ($12,632 ) ($19,757 ) Other comprehensive income (loss) before reclassifications 621 (551 ) (741 ) (671 ) Amounts reclassified from accumulated other comprehensive income — 499 644 1,143 Net other comprehensive income (loss) 621 (52 ) (97 ) 472 Reclassification of income tax effects due to the adoption of ASU 2018-02 (1,330 ) (76 ) (2,819 ) (4,225 ) Balance at December 31, 2017 ($7,534 ) ($428 ) ($15,548 ) ($23,510 )

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Calculation of Earnings Per Common Share	The following table presents the calculation of earnings per common share: (Dollars and shares in thousands, except per share amounts) Years ended December 31, 2019 2018 2017 Earnings per common share - basic: Net income $69,118 $68,432 $45,925 Less dividends and undistributed earnings allocated to participating securities (139 ) (144 ) (108 ) Net income available to common shareholders $68,979 $68,288 $45,817 Weighted average common shares 17,331 17,272 17,207 Earnings per common share - basic $3.98 $3.95 $2.66 Earnings per common share - diluted: Net income $69,118 $68,432 $45,925 Less dividends and undistributed earnings allocated to participating securities (139 ) (144 ) (108 ) Net income available to common shareholders $68,979 $68,288 $45,817 Weighted average common shares 17,331 17,272 17,207 Dilutive effect of common stock equivalents 83 119 131 Weighted average diluted common shares 17,414 17,391 17,338 Earnings per common share - diluted $3.96 $3.93 $2.64

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Schedule of Remaining Operating Lease Payments, Inclusive of Renewal Options	The following table presents the undiscounted annual lease payments under the terms of the Corporation’s operating leases at December 31, 2019 , including a reconciliation to the present value of operating lease liabilities recognized in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Years ending December 31: 2020 $3,493 2021 3,291 2022 3,165 2023 3,097 2024 2,904 2025 and thereafter 21,818 Total operating lease payments (1) 37,768 Less interest 8,907 Present value of operating lease liabilities (2) $28,861 (1) Includes $2.4 million related to options to extend lease terms that are reasonably certain of being exercised. (2) Includes short-term operating lease liabilities of $2.5 million .
Schedule of Total Lease Expense	The following table presents the components of total lease expense and operating cash flows: (Dollars in thousands) Year ended December 31, 2019 Lease Expense: Operating lease expense $3,724 Variable lease expense 49 Total lease expense (1) $3,773 Cash Paid: Cash paid reducing operating lease liabilities $3,586 (1) Included in net occupancy expenses in the Consolidated Income Statement.
Schedule of Future Minimum Annual Lease Payments	The following table presents the minimum annual lease payments under the terms of these leases, exclusive of renewal provisions at December 31, 2018 : (Dollars in thousands) Years ending December 31: 2019 $3,544 2020 2,980 2021 2,677 2022 2,293 2023 2,059 2024 and thereafter 22,648 Total minimum lease payments $36,201

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Financial Instruments with Off Balance Sheet Risk	The following table presents the contractual and notional amounts of financial instruments with off-balance sheet risk: (Dollars in thousands) December 31, 2019 2018 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $471,338 $533,884 Home equity lines 295,687 270,462 Other loans 88,613 46,698 Standby letters of credit 13,710 7,706 Financial instruments whose notional amounts exceed the amount of credit risk: Mortgage loan commitments: Interest rate lock commitments 51,439 30,766 Forward sale commitments 94,829 61,993 Loan related derivative contracts: Interest rate swaps with customers 813,458 648,050 Mirror swaps with counterparties 813,458 648,050 Risk participation-in agreements 72,866 46,510 Foreign exchange contracts — 2,784 Interest rate risk management contracts: Interest rate swaps 60,000 60,000

Parent Company Financial Stat_2

Parent Company Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Parent Company Only Balance Sheet	The following tables present parent company only financial statements of the Bancorp, reflecting the investment in the Bank on the equity basis of accounting. The Statements of Changes in Shareholders’ Equity for the parent company only are identical to the Consolidated Statements of Changes in Shareholders’ Equity and are therefore not presented. Balance Sheets (Dollars in thousands, except par value) December 31, 2019 2018 Assets: Cash on deposit with bank subsidiary $1,838 $1,912 Investment in subsidiaries at equity value: Bank 521,969 467,657 Non-bank 1,882 1,869 Dividends receivable from bank subsidiary 9,575 7,762 Other assets 232 190 Total assets $535,496 $479,390 Liabilities: Junior subordinated debentures $22,681 $22,681 Dividends payable 9,252 8,439 Other liabilities 71 86 Total liabilities 32,004 31,206 Shareholders’ Equity: Common stock of $.0625 par value; authorized 60,000,000 shares; issued and outstanding 17,363,455 shares in 2019 and 17,302,037 in 2018 1,085 1,081 Paid-in capital 123,281 119,888 Retained earnings 390,363 355,524 Accumulated other comprehensive loss (11,237 ) (28,309 ) Total shareholders’ equity 503,492 448,184 Total liabilities and shareholders’ equity $535,496 $479,390
Parent Company Only Income Statement	Statements of Income (Dollars in thousands) Years ended December 31, 2019 2018 2017 Income: Dividends from subsidiaries: Bank $36,796 $32,394 $27,900 Non-bank 27 24 18 Total income 36,823 32,418 27,918 Expenses: Interest on junior subordinated debentures 980 869 613 Legal and professional fees 147 187 169 Change in fair value of contingent consideration — (187 ) (643 ) Other 337 324 298 Total expenses 1,464 1,193 437 Income before income taxes 35,359 31,225 27,481 Income tax benefit 301 284 340 Income before equity in undistributed earnings (losses) of subsidiaries 35,660 31,509 27,821 Equity in undistributed earnings (losses) of subsidiaries: Bank 33,445 36,876 18,193 Non-bank 13 47 (89 ) Net income $69,118 $68,432 $45,925
Parent Company Only Cash Flow Statement	Statements of Cash Flows (Dollars in thousands) Years ended December 31, 2019 2018 2017 Cash flow from operating activities: Net income $69,118 $68,432 $45,925 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed (earnings) losses of subsidiaries: Bank (33,445 ) (36,876 ) (18,193 ) Non-bank (13 ) (47 ) 89 (Increase) decrease in dividend receivable (1,813 ) 8 (1,252 ) (Increase) decrease in other assets (43 ) 70 72 (Decrease) increase in accrued expenses and other liabilities (15 ) 17 22 Change in fair value of contingent consideration liability — (187 ) (643 ) Tax benefit from stock option exercises and other equity awards 248 496 508 Other, net (195 ) (465 ) (673 ) Net cash provided by operating activities 33,842 31,448 25,855 Cash flows from financing activities: Payment of contingent consideration liability — (1,217 ) — Net proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered 273 (671 ) 366 Cash dividends paid (34,189 ) (29,312 ) (26,300 ) Net cash used in financing activities (33,916 ) (31,200 ) (25,934 ) Net (decrease) increase in cash (74 ) 248 (79 ) Cash at beginning of year 1,912 1,664 1,743 Cash at end of year $1,838 $1,912 $1,664

Selected Quarterly Consolidat_2

Selected Quarterly Consolidated Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Consolidated Financial Data (Unaudited)	(Dollars and shares in thousands, except per share amounts) 2019 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $50,194 $50,559 $49,527 $47,383 Interest expense 15,610 16,701 16,549 15,389 Net interest income 34,584 33,858 32,978 31,994 Provision for loan losses 650 525 400 — Net interest income after provision for loan losses 33,934 33,333 32,578 31,994 Noninterest income 15,367 16,753 18,342 16,618 Noninterest expense 26,964 28,151 26,870 28,755 Income before income taxes 22,337 21,935 24,050 19,857 Income tax expense 4,842 4,662 5,236 4,321 Net income $17,495 $17,273 $18,814 $15,536 Net income available to common shareholders $17,461 $17,238 $18,778 $15,502 Weighted average common shares outstanding - basic 17,304 17,330 17,338 17,351 Weighted average common shares outstanding - diluted 17,401 17,405 17,414 17,436 Per share information: Basic earnings per common share $1.01 $0.99 $1.08 $0.89 Diluted earnings per common share $1.00 $0.99 $1.08 $0.89 Cash dividends declared per share $0.47 $0.51 $0.51 $0.51 (Dollars and shares in thousands, except per share amounts) 2018 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $40,440 $43,286 $45,164 $47,517 Interest expense 8,588 10,175 11,715 13,639 Net interest income 31,852 33,111 33,449 33,878 Provision for loan losses — 400 350 800 Net interest income after provision for loan losses 31,852 32,711 33,099 33,078 Noninterest income 15,743 15,993 15,215 15,163 Noninterest expense 27,130 26,288 26,062 26,682 Income before income taxes 20,465 22,416 22,252 21,559 Income tax expense 4,254 4,742 4,741 4,523 Net income $16,211 $17,674 $17,511 $17,036 Net income available to common shareholders $16,173 $17,636 $17,475 $17,004 Weighted average common shares outstanding - basic 17,234 17,272 17,283 17,297 Weighted average common shares outstanding - diluted 17,345 17,387 17,382 17,385 Per share information: Basic earnings per common share $0.94 $1.02 $1.01 $0.98 Diluted earnings per common share $0.93 $1.01 $1.01 $0.98 Cash dividends declared per share $0.43 $0.43 $0.43 $0.47

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Line Items]
Federal Home Loan Bank Stock, redemption period, years after membership termination	5 years
Investment in real estate limited partnerships, ownership percentage	99.90%
Investment in real estate limited partnerships, number of investments	3
Premises and Improvements [Member] | Minimum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	5 years
Premises and Improvements [Member] | Maximum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	40 years
Furniture, Fixtures and Equipment [Member] | Minimum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	3 years
Furniture, Fixtures and Equipment [Member] | Maximum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	20 years

Recently Issued Accounting Pr_2

Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Jan. 01, 2020	Dec. 31, 2019		Dec. 31, 2018
Operating lease right-of-use assets	$ 28,900		$ 26,792		$ 0
Operating lease liabilities	30,900		28,861	[1]	0
Rent-related liabilities	2,900
Reduction of deferred tax assets	222
Cumulative effect of change in accounting principle			722
Held to maturity securities, amortized cost			0		10,415
Held to maturity securities, fair value			0		10,316
Unrealized losses in accumulated other comprehensive income			(11,237)		$ (28,309)
Retained Earnings [Member]
Cumulative effect of change in accounting principle	722		$ 722
Adjustments for Change in Accounting Principle [Domain]
Held to maturity securities, amortized cost	10,400
Held to maturity securities, fair value	10,300
Unrealized losses in accumulated other comprehensive income	$ (75)
Minimum [Member]
Cumulative effect of change in accounting principle		$ 4,200
Range of increase in ACL		5,500
Range of increase in DTA		1,300
Maximum [Member]
Cumulative effect of change in accounting principle		6,500
Range of increase in ACL		8,500
Range of increase in DTA		$ 2,000
[1]	Includes short-term operating lease liabilities of $2.5 million .

Cash and Due from Banks (Narrat

Cash and Due from Banks (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Abstract]
Average reserve deposited with the Board of Governors of the Federal Reserve Bank	$ 27.9	$ 21.6
Interest-bearing deposits in other banks	$ 83.4	$ 33.7

Securities (Narrative) (Details

Securities (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)security	Jan. 01, 2019USD ($)	Dec. 31, 2018USD ($)security
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Held to maturity securities, amortized cost	$ 0		$ 10,415
Held to maturity securities, fair value	0		10,316
Unrealized losses in accumulated other comprehensive income	(11,237)		(28,309)
Securities available for sale and held to maturity pledged as collateral, fair value	431,900		$ 439,700
Amortized cost of callable debt securities	180,400
Fair value of callable debt securities	$ 179,100
Number of securities in a continuous unrealized loss position total | security	41		90
Unrealized losses of securities in a continuous unrealized loss position total	$ 4,900		$ 24,396
Minimum [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Callable debt securities, maturity period	4 months
Callable debt securities, call feature period	1 month
Maximum [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Callable debt securities, maturity period	17 years
Callable debt securities, call feature period	2 years
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position total | security	5		5
Number of companies issuing securities in continuous unrealized loss position | security	4
Amortized cost of trust preferred securities of individual name issuers that are below investment grade	$ 2,000
Unrealized losses of trust preferred securities of individual name issuers that are below investment grade	(161)
Unrealized losses of securities in a continuous unrealized loss position total	$ 745		$ 1,535
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position total | security	3		8
Unrealized losses of securities in a continuous unrealized loss position total	$ 958		$ 1,777
Adjustments for Change in Accounting Principle [Domain]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Held to maturity securities, amortized cost		$ 10,400
Held to maturity securities, fair value		10,300
Unrealized losses in accumulated other comprehensive income		$ (75)

Securities (Summary of Investme

Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	$ 895,273	$ 949,720
Available for sale securities unrealized gains	9,117	2,387
Available for sale securities unrealized losses	(4,900)	(24,297)
Available for sale debt securities, at fair value	899,490	927,810
Held to maturity securities, amortized cost	0	10,415
Held to maturity securities unrealized gains		0
Held to Matruity securities unrealized losses		(99)
Held to maturity securities, fair value	0	10,316
Total securities amortized cost	895,273	960,135
Total securities unrealized gains	9,117	2,387
Total securities unrealized losses	(4,900)	(24,396)
Total securities fair value	899,490	938,126
Available for sale securities amortized cost	895,273
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	157,255	246,708
Available for sale securities unrealized gains	626	442
Available for sale securities unrealized losses	(233)	(4,467)
Available for sale debt securities, at fair value	157,648	242,683
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	713,553	675,368
Available for sale securities unrealized gains	8,491	1,943
Available for sale securities unrealized losses	(2,964)	(16,518)
Available for sale debt securities, at fair value	719,080	660,793
Held to maturity securities, amortized cost		10,415
Held to maturity securities unrealized gains		0
Held to Matruity securities unrealized losses		(99)
Held to maturity securities, fair value		10,316
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost		935
Available for sale securities unrealized gains		2
Available for sale securities unrealized losses		0
Available for sale debt securities, at fair value		937
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	13,324	13,307
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(745)	(1,535)
Available for sale debt securities, at fair value	12,579	11,772
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	11,141	13,402
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(958)	(1,777)
Available for sale debt securities, at fair value	$ 10,183	$ 11,625

Securities (Securities by Contr

Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities maturities wIthin 1 year amortized cost	$ 103,241
Available for sale debt securities maturities 1-5 years amortized cost	349,290
Available for sale debt securities maturities 5-10 years amortized cost	264,354
Available for sale debt securities maturities after 10 years amortized cost	178,388
Available for sale securities amortized cost	895,273
Available for sale debt securities maturities within 1 year fair value	103,962
Available for sale debt securities maturities 1-5 years fair value	351,538
Available for sale debt securities maturities 5-10 years fair value	264,958
Available for sale debt securities maturities after 10 years fair value	179,032
Available for sale debt securities fair value	$ 899,490

Securities (Securities in a Con

Securities (Securities in a Continuous Unrealized Loss Position) (Details) $ in Thousands	Dec. 31, 2019USD ($)security	Dec. 31, 2018USD ($)security
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	7	13
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 61,514	$ 48,258
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (192)	$ (448)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	34	77
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 289,468	$ 617,932
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (4,708)	$ (23,948)
Number of securities in a continuous unrealized loss position total | security	41	90
Fair value of securities in a continuous unrealized loss position total	$ 350,982	$ 666,190
Unrealized losses of securities in a continuous unrealized loss position total	$ (4,900)	$ (24,396)
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	3	0
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 20,364	$ 0
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (136)	$ 0
Number of securities in a continuous unrealized loss position for 12 months or longer | security	3	16
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 49,902	$ 157,032
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (97)	$ (4,467)
Number of securities in a continuous unrealized loss position total | security	6	16
Fair value of securities in a continuous unrealized loss position total	$ 70,266	$ 157,032
Unrealized losses of securities in a continuous unrealized loss position total	$ (233)	$ (4,467)
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	4	10
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 41,150	$ 47,060
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (56)	$ (439)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	23	51
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 216,804	$ 438,701
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (2,908)	$ (16,178)
Number of securities in a continuous unrealized loss position total | security	27	61
Fair value of securities in a continuous unrealized loss position total	$ 257,954	$ 485,761
Unrealized losses of securities in a continuous unrealized loss position total	$ (2,964)	$ (16,617)
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	0	0
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ 0
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ 0
Number of securities in a continuous unrealized loss position for 12 months or longer | security	5	5
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 12,579	$ 11,772
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (745)	$ (1,535)
Number of securities in a continuous unrealized loss position total | security	5	5
Fair value of securities in a continuous unrealized loss position total	$ 12,579	$ 11,772
Unrealized losses of securities in a continuous unrealized loss position total	$ (745)	$ (1,535)
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	0	3
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ 1,198
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ (9)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	3	5
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 10,183	$ 10,427
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (958)	$ (1,768)
Number of securities in a continuous unrealized loss position total | security	3	8
Fair value of securities in a continuous unrealized loss position total	$ 10,183	$ 11,625
Unrealized losses of securities in a continuous unrealized loss position total	$ (958)	$ (1,777)

Securities Securities (Schedule

Securities Securities (Schedule of Amounts from Sales of Securities) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Gain (Loss) on Securities [Line Items]
Proceeds from sales		$ 11,877	$ 0	$ 0
Gross realized gains		0	0	0
Gross realized losses		(53)	0	0
Net realized losses on securities	[1]	$ (53)	$ 0	$ 0
[1]	As reported in the Consolidated Statements of Income.

Loans (Narrative) (Details)

Loans (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Net unamortized loan origination costs	$ 5,300	$ 4,700
Net unamortized premiums on purchased loans	995	703
Loans pledged as collateral	2,100,000	2,000,000
Residential loans in process of foreclosure	5,800	761
Nonaccrual loans	$ 11,500	$ 8,600

Loans (Summary of Loans) (Detai

Loans (Summary of Loans) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[1]	$ 3,892,999	$ 3,680,360
Percent of total loans	[1]	100.00%	100.00%
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[2]	$ 1,547,572	$ 1,392,408
Percent of total loans	[2]	40.00%	38.00%
Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[3]	$ 585,289	$ 620,704
Percent of total loans	[3]	15.00%	17.00%
Total Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 2,132,861	$ 2,013,112
Percent of total loans		55.00%	55.00%
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[4]	$ 1,449,090	$ 1,360,387
Percent of total loans	[4]	37.00%	37.00%
Home Equity [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 290,874	$ 280,626
Percent of total loans		7.00%	8.00%
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[5]	$ 20,174	$ 26,235
Percent of total loans	[5]	1.00%	0.00%
Total Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 311,048	$ 306,861
Percent of total loans		8.00%	8.00%
[1]	Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 .
[2]	Commercial real estate (“CRE”) consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings.
[3]	Commercial and industrial (“C&I”) consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans.

Loans (Past Due Loans) (Details

Loans (Past Due Loans) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Past due loans		$ 15,689	$ 13,622
Current loans		3,877,310	3,666,738
Total loans	[1]	3,892,999	3,680,360
Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		1,433	1,080
Current loans		1,546,139	1,391,328
Total loans	[2]	1,547,572	1,392,408
Commercial & Industrial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		1	0
Current loans		585,288	620,704
Total loans	[3]	585,289	620,704
Total Commercial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		1,434	1,080
Current loans		2,131,427	2,012,032
Total loans		2,132,861	2,013,112
Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		11,429	10,520
Current loans		1,437,661	1,349,867
Total loans	[4]	1,449,090	1,360,387
Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		2,696	1,989
Current loans		288,178	278,637
Total loans		290,874	280,626
Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		130	33
Current loans		20,044	26,202
Total loans	[5]	20,174	26,235
Total Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		2,826	2,022
Current loans		308,222	304,839
Total loans		311,048	306,861
30-59
Financing Receivable, Past Due [Line Items]
Past due loans		6,418	7,787
30-59 | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		830	155
30-59 | Commercial & Industrial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		1	0
30-59 | Total Commercial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		831	155
30-59 | Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		4,574	6,318
30-59 | Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		971	1,281
30-59 | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		42	33
30-59 | Total Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		1,013	1,314
60-89
Financing Receivable, Past Due [Line Items]
Past due loans		2,884	3,774
60-89 | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		0	925
60-89 | Commercial & Industrial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		0	0
60-89 | Total Commercial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		0	925
60-89 | Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		2,155	2,693
60-89 | Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		729	156
60-89 | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		0	0
60-89 | Total Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		729	156
Over 90
Financing Receivable, Past Due [Line Items]
Past due loans		6,387	2,061
Over 90 | Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		603	0
Over 90 | Commercial & Industrial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		0	0
Over 90 | Total Commercial [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		603	0
Over 90 | Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		4,700	1,509
Over 90 | Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		996	552
Over 90 | Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		88	0
Over 90 | Total Consumer [Member]
Financing Receivable, Past Due [Line Items]
Past due loans		$ 1,084	$ 552
[1]	Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 .
[2]	Commercial real estate (“CRE”) consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings.
[3]	Commercial and industrial (“C&I”) consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans.

Loans (Impaired Loans) (Details

Loans (Impaired Loans) (Details) - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	$ 15,527,000	$ 16,313,000
Collateral dependent impaired loans	[1]	2,257,000	523,000
Total Recorded Investment of Impaired Loans	[1]	17,784,000	16,836,000
Unpaid Principal of Impaired Loans with No Related Allowance		16,363,000	16,713,000
Unpaid Principal of Impaired Loans with Related Allowance		2,606,000	570,000
Total Unpaid Principal of Impaired Loans		18,969,000	17,283,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		968,000	127,000
Average Recorded Investment of Impaired Loans		16,122,000	17,349,000	$ 30,269,000
Interest Income Recognized on Impaired Loans		640,000	709,000	845,000
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	925,000
Collateral dependent impaired loans	[1]	603,000	0
Unpaid Principal of Impaired Loans with No Related Allowance		0	926,000
Unpaid Principal of Impaired Loans with Related Allowance		926,000	0
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	0
Average Recorded Investment of Impaired Loans		864,000	1,050,000	8,425,000
Interest Income Recognized on Impaired Loans		1,000	0	79,000
Commercial & Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	4,681,000
Collateral dependent impaired loans	[1]	657,000	52,000
Unpaid Principal of Impaired Loans with No Related Allowance		0	4,732,000
Unpaid Principal of Impaired Loans with Related Allowance		657,000	73,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		580,000	0
Average Recorded Investment of Impaired Loans		2,149,000	5,403,000	6,445,000
Interest Income Recognized on Impaired Loans		106,000	259,000	281,000
Total Commercial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	5,606,000
Collateral dependent impaired loans	[1]	1,260,000	52,000
Total Recorded Investment of Impaired Loans	[1]	1,260,000	5,658,000
Unpaid Principal of Impaired Loans with No Related Allowance		0	5,658,000
Unpaid Principal of Impaired Loans with Related Allowance		1,583,000	73,000
Total Unpaid Principal of Impaired Loans		1,583,000	5,731,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		580,000	0
Average Recorded Investment of Impaired Loans		3,013,000	6,453,000	14,870,000
Interest Income Recognized on Impaired Loans		107,000	259,000	360,000
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	13,968,000	9,347,000
Collateral dependent impaired loans	[1]	687,000	364,000
Total Recorded Investment of Impaired Loans	[1]	14,655,000	9,711,000
Unpaid Principal of Impaired Loans with No Related Allowance		14,803,000	9,695,000
Unpaid Principal of Impaired Loans with Related Allowance		714,000	390,000
Total Unpaid Principal of Impaired Loans		15,517,000	10,085,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		95,000	100,000
Average Recorded Investment of Impaired Loans		11,575,000	9,645,000	14,571,000
Interest Income Recognized on Impaired Loans		473,000	393,000	444,000
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	1,471,000	1,360,000
Collateral dependent impaired loans	[1]	292,000	85,000
Unpaid Principal of Impaired Loans with No Related Allowance		1,472,000	1,360,000
Unpaid Principal of Impaired Loans with Related Allowance		291,000	85,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		291,000	24,000
Average Recorded Investment of Impaired Loans		1,466,000	1,182,000	685,000
Interest Income Recognized on Impaired Loans		58,000	52,000	31,000
Other Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	88,000	0
Collateral dependent impaired loans	[1]	18,000	22,000
Unpaid Principal of Impaired Loans with No Related Allowance		88,000	0
Unpaid Principal of Impaired Loans with Related Allowance		18,000	22,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		2,000	3,000
Average Recorded Investment of Impaired Loans		68,000	69,000	143,000
Interest Income Recognized on Impaired Loans		2,000	5,000	10,000
Total Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	1,559,000	1,360,000
Collateral dependent impaired loans	[1]	310,000	107,000
Total Recorded Investment of Impaired Loans	[1]	1,869,000	1,467,000
Unpaid Principal of Impaired Loans with No Related Allowance		1,560,000	1,360,000
Unpaid Principal of Impaired Loans with Related Allowance		309,000	107,000
Total Unpaid Principal of Impaired Loans		1,869,000	1,467,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		293,000	27,000
Average Recorded Investment of Impaired Loans		1,534,000	1,251,000	828,000
Interest Income Recognized on Impaired Loans		$ 60,000	$ 57,000	$ 41,000
[1]	The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest.

Loans (Nonaccrual Loans) (Detai

Loans (Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 17,408	$ 11,707
Accruing loans 90 days or more past due	0	0
Current Payment Status [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans current on payment	5,900	3,100
Commercial Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	603	925
Commercial & Industrial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	657	0
Total Commercial [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,260	925
Residential Real Estate [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	14,297	9,346
Home Equity [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,763	1,436
Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	88	0
Total Consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 1,851	$ 1,436

Loans (Narrative - Troubled Deb

Loans (Narrative - Troubled Debt Restructurings) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)loan	Dec. 31, 2018USD ($)loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded investment	$ 869	$ 5,600
Specific reserves on troubled debt restructurings	$ 97	$ 103
Number of Loans Modified as a Troubled Debt Restructuring | loan	0	1
Pre-Modification Recorded Investment	$ 0	$ 608
Post-Modification Recorded Investment	$ 0	$ 608
Payment Default [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan	0	1
Recorded Investment on Modifications with Subsequent Default	$ 0	$ 608

Loans (Credit Quality Indicator

Loans (Credit Quality Indicators - Commercial) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	$ 1,546,139	$ 1,387,666
Pass [Member] | Commercial & Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	549,416	559,019
Pass [Member] | Total Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	2,095,555	1,946,685
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	830	205
Special Mention [Member] | Commercial & Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	24,961	50,426
Special Mention [Member] | Total Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	25,791	50,631
Classified [Member] | Commercial Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	603	4,537
Classified [Member] | Commercial & Industrial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	10,912	11,259
Classified [Member] | Total Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans by credit quality indicator	$ 11,515	$ 15,796

Loans (Credit Quality Indicat_2

Loans (Credit Quality Indicators - Residential, Consumer) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Current loans	$ 3,877,310	$ 3,666,738
Past due loans	15,689	13,622
Residential Real Estate [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current loans	1,437,661	1,349,867
Past due loans	11,429	10,520
Home Equity [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current loans	288,178	278,637
Past due loans	2,696	1,989
Other Consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current loans	20,044	26,202
Past due loans	130	33
Total Consumer [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Current loans	308,222	304,839
Past due loans	$ 2,826	$ 2,022

Loans (Analysis of Loan Servici

Loans (Analysis of Loan Servicing Rights) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loan Servicing Rights [Roll Forward]
Beginning balance	$ 3,651	$ 3,613	$ 3,493
Loan servicing rights capitalized	902	905	1,104
Amortization	(1,027)	(867)	(984)
Ending balance	3,526	3,651	3,613
Valuation Allowance [Roll Forward]
Beginning balance	0	0	0
Loan servicing rights capitalized	0	0	0
Amortization	0	0	0
Ending balance	0	0	0
Total Loan Servicing Rights [Roll Forward]
Beginning Balance	3,651	3,613	3,493
Loan servicing rights capitalized	902	905	1,104
Amortization	(1,027)	(867)	(984)
Ending balance	$ 3,526	$ 3,651	$ 3,613

Loans (Estimated Aggregate Amor

Loans (Estimated Aggregate Amortization Expense) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Receivables [Abstract]
Amortization Expense, Next Twelve Months	$ 825
Amortization Expense, Year Two	632
Amortization Expense, Year Three	484
Amortization Expense, Year Four	371
Amortization Expense, Year Five	284
Amortization Expense, Thereafter	930
Total estimated amortization expense	$ 3,526	$ 3,651	$ 3,613	$ 3,493

Loans (Loans Serviced for Other

Loans (Loans Serviced for Others, by Type of Loan) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	$ 746,944	$ 730,752
Residential Mortgages [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	586,996	588,534
Commercial Loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	$ 159,948	$ 142,218

Allowance for Loan Losses (Allo

Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 27,072	$ 26,488	$ 26,004
Charge-offs	(2,020)	(1,187)	(2,462)
Recoveries	387	221	346
Provision	1,575	1,550	2,600
Ending Balance	27,014	27,072	26,488
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	15,381	12,729	11,166
Charge-offs	(1,028)	(627)	(1,867)
Recoveries	125	25	82
Provision	263	3,254	3,348
Ending Balance	14,741	15,381	12,729
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	5,847	5,580	6,992
Charge-offs	(21)	(10)	(336)
Recoveries	168	119	169
Provision	(2,073)	158	(1,245)
Ending Balance	3,921	5,847	5,580
Total Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	21,228	18,309	18,158
Charge-offs	(1,049)	(637)	(2,203)
Recoveries	293	144	251
Provision	(1,810)	3,412	2,103
Ending Balance	18,662	21,228	18,309
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	3,987	5,427	5,252
Charge-offs	(486)	(250)	(74)
Recoveries	0	21	39
Provision	3,114	(1,211)	210
Ending Balance	6,615	3,987	5,427
Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,603	2,412	1,889
Charge-offs	(390)	(193)	(79)
Recoveries	72	29	33
Provision	105	(645)	569
Ending Balance	1,390	1,603	2,412
Other Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	254	340	705
Charge-offs	(95)	(107)	(106)
Recoveries	22	27	23
Provision	166	(6)	(282)
Ending Balance	347	254	340
Total Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,857	2,752	2,594
Charge-offs	(485)	(300)	(185)
Recoveries	94	56	56
Provision	271	(651)	287
Ending Balance	$ 1,737	$ 1,857	$ 2,752

Allowance for Loan Losses (Al_2

Allowance for Loan Losses (Allowance for Loan Losses by Segment & Impairment Methodology) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		$ 17,783	$ 16,816
Loans related allowance individually evaluated for impairment		968	127
Loans collectively evaluated for impairment		3,875,216	3,663,544
Loans related allowance collectively evaluated for impairment		26,046	26,945
Total loans	[1]	3,892,999	3,680,360
Allowance		27,014	27,072
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		603	925
Loans related allowance individually evaluated for impairment		0	0
Loans collectively evaluated for impairment		1,546,969	1,391,483
Loans related allowance collectively evaluated for impairment		14,741	15,381
Total loans	[2]	1,547,572	1,392,408
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		657	4,714
Loans related allowance individually evaluated for impairment		580	0
Loans collectively evaluated for impairment		584,632	615,990
Loans related allowance collectively evaluated for impairment		3,341	5,847
Total loans	[3]	585,289	620,704
Total Commercial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		1,260	5,639
Loans related allowance individually evaluated for impairment		580	0
Loans collectively evaluated for impairment		2,131,601	2,007,473
Loans related allowance collectively evaluated for impairment		18,082	21,228
Total loans		2,132,861	2,013,112
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		14,654	9,710
Loans related allowance individually evaluated for impairment		95	100
Loans collectively evaluated for impairment		1,434,436	1,350,677
Loans related allowance collectively evaluated for impairment		6,520	3,887
Total loans	[4]	1,449,090	1,360,387
Home Equity [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		1,763	1,445
Loans related allowance individually evaluated for impairment		291	24
Loans collectively evaluated for impairment		289,111	279,182
Loans related allowance collectively evaluated for impairment		1,099	1,579
Total loans		290,874	280,626
Other Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		106	22
Loans related allowance individually evaluated for impairment		2	3
Loans collectively evaluated for impairment		20,068	26,212
Loans related allowance collectively evaluated for impairment		345	251
Total loans	[5]	20,174	26,235
Total Consumer [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		1,869	1,467
Loans related allowance individually evaluated for impairment		293	27
Loans collectively evaluated for impairment		309,179	305,394
Loans related allowance collectively evaluated for impairment		1,444	1,830
Total loans		$ 311,048	$ 306,861
[1]	Includes net unamortized loan origination costs of $5.3 million and $4.7 million , respectively, at December 31, 2019 and 2018 and net unamortized premiums on purchased loans of $995 thousand and $703 thousand , respectively, at December 31, 2019 and 2018 .
[2]	Commercial real estate (“CRE”) consists of commercial mortgages primarily secured by income-producing property, as well as construction and development loans. Construction and development loans are made to businesses for land development or the on-site construction of industrial, commercial, or residential buildings.
[3]	Commercial and industrial (“C&I”) consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Residential real estate consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	Other consists of loans to individuals secured by general aviation aircraft and other personal installment loans.

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Land	$ 5,921	$ 6,020
Premises and Improvements	40,982	40,210
Furniture fixtures and equipment	24,760	24,798
Premises and equipment, gross	71,663	71,028
Less accumulated depreciation	42,963	42,023
Total premises and equipment, net	28,700	29,005
Depreciation expense	$ 3,300	$ 3,300	$ 3,500

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangibles	$ 943	$ 979	$ 1,035
Weston Financial acquisition [Member] | Advisory Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset useful life (in years)	20 years
Halsey acquisition [Member] | Advisory Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset useful life (in years)	15 years

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill	$ 63,909	$ 63,909
Commercial Banking [Member]
Goodwill [Line Items]
Goodwill	22,591	22,591
Wealth Management Services [Member]
Goodwill [Line Items]
Goodwill	$ 41,318	$ 41,318

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets (Schedule of Components of Intangible Assets) (Details) - Advisory Contracts [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 20,803	$ 20,803
Accumulated amortization	13,585	12,641
Net amount	$ 7,218	$ 8,162

Goodwill and Intangible Asset_5

Goodwill and Intangible Assets (Schedule of Amortization Annual Expense) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 914
Finite-Lived Intangible Assets, Amortization Expense, Year Two	890
Finite-Lived Intangible Assets, Amortization Expense, Year Three	860
Finite-Lived Intangible Assets, Amortization Expense, Year Four	843
Finite-Lived Intangible Assets, Amortization Expense, Year Five	826
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 2,885

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Adjustment to net deferred tax assets for enacted changes in federal tax law	$ 0	$ 0	$ 6,170
Unrecognized tax benefits	$ 0	$ 0

Income Taxes (Schedule of Compo

Income Taxes (Schedule of Components of Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current tax expense:
Federal									$ 17,298	$ 15,460	$ 23,827
State									3,254	2,863	2,201
Total current tax expense									20,552	18,323	26,028
Deferred tax (benefit) expense:
Federal									(1,294)	63	5,717
State									(197)	(126)	(30)
Total deferred (benefit) tax expense									(1,491)	(63)	5,687
Total income tax expense	$ 4,321	$ 5,236	$ 4,662	$ 4,842	$ 4,523	$ 4,741	$ 4,742	$ 4,254	$ 19,061	$ 18,260	$ 31,715

Income Taxes (Schedule of Incom

Income Taxes (Schedule of Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Tax expense at Federal statutory rate									$ 18,518	$ 18,205	$ 27,174
Federal statutory rate									21.00%	21.00%	35.00%
(Decrease) increase in taxes resulting from:
Tax-exempt income, net									$ (814)	$ (809)	$ (1,313)
Tax-exempt income, net, rate									(0.90%)	(0.90%)	(1.70%)
Dividends received deduction									$ (36)	$ (45)	$ (55)
Dividends received deduction, rate									0.00%	(0.10%)	(0.10%)
BOLI									$ (494)	$ (461)	$ (757)
BOLI, rate									(0.60%)	(0.50%)	(0.90%)
Share-based compensation									$ (221)	$ (444)	$ (481)
Share-based compensation, rate									(0.30%)	(0.50%)	(0.60%)
Federal tax credits									$ (364)	$ (364)	$ (364)
Federal tax credits, rate									(0.40%)	(0.40%)	(0.50%)
Change in fair value of contingent consideration									$ 0	$ (39)	$ (225)
Change in fair value of contingent consideration, rate									0.00%	(0.10%)	(0.30%)
State income tax expense, net of federal tax benefit									$ 2,417	$ 2,162	$ 1,411
State income tax expense, net of federal income tax benefit, rate									2.70%	2.50%	1.80%
Adjustment to net deferred tax assets for enacted changes in federal tax law									$ 0	$ 0	$ 6,170
Adjustment to net deferred tax asset for enacted changes in federal tax law, rate									0.00%	0.00%	7.90%
Other									$ 55	$ 55	$ 155
Other, rate									0.10%	0.10%	0.20%
Total income tax expense	$ 4,321	$ 5,236	$ 4,662	$ 4,842	$ 4,523	$ 4,741	$ 4,742	$ 4,254	$ 19,061	$ 18,260	$ 31,715
Effective tax rate									21.60%	21.10%	40.80%

Income Taxes (Schedule of Gross

Income Taxes (Schedule of Gross Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Allowance for loan losses	$ 6,348	$ 6,362
Operating lease liabilities	6,782	0
Defined benefit pension obligations	1,361	420
Deferred compensation	4,200	3,688
Deferred loan origination fees	1,505	1,410
Share-based compensation	1,358	1,124
Net unrealized losses on available for sale debt securities	0	5,149
Other	2,031	1,917
Deferred tax assets	23,585	20,070
Deferred tax liabilities:
Net unrealized gains on available for sale debt securities	(991)	0
Amortization of intangibles	(1,696)	(1,918)
Operating lease right-of-use assets	(6,296)	0
Deferred loan origination costs	(4,084)	(3,897)
Loan servicing rights	(829)	(858)
Other	(1,388)	(1,120)
Deferred tax liabilities	(15,284)	(7,793)
Net deferred tax asset	$ 8,301	$ 12,277

Deposits (Narrative) (Details)

Deposits (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Time Certificates of Deposit [Abstract]
Time deposits greater than FDIC limit	$ 147.3	$ 129.3

Deposits (Summary of Deposits)

Deposits (Summary of Deposits) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Deposits [Abstract]
Noninterest-bearing demand deposits		$ 609,924	$ 603,216
Interest-bearing demand deposits		159,938	178,733
NOW accounts		520,295	466,568
Money market accounts		765,899	646,878
Savings accounts		373,503	373,545
Time deposits	[1]	1,069,323	1,255,108
Total deposits		$ 3,498,882	$ 3,524,048
[1]	Includes wholesale brokered time deposits.

Deposits (Schedule of Time Cert

Deposits (Schedule of Time Certifcates of Deposit Maturities) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Schedule Maturity Abstract]
Time Deposits Scheduled Maturity, Next Twelve Months		$ 751,525
Time Deposits Scheduled Maturity, Year Two		161,034
Time Deposits Scheduled Maturity, Year Three		105,846
Time Deposits Scheduled Maturity, Year Four		32,462
Time Deposits Scheduled Maturity, Year Five		18,326
Time Deposits Scheduled Maturity, Thereafter		130
Time deposits	[1]	$ 1,069,323	$ 1,255,108
Weighted Average Rate [Abstract]
Time Deposits Weighted Average Rate, Next Twelve Months		1.95%
Time Deposits Weighted Average Rate, Year Two		2.27%
Time Deposits Weighted Average Rate, Year Three		2.42%
Time Deposits Weighted Average Rate, Year Four		2.04%
Time Deposits Weighted Average Rate, Year Five		1.58%
Time Deposits Weighted Average Rate, Thereafter		2.26%
Total Time Deposits Weighted Average Rate		2.04%
[1]	Includes wholesale brokered time deposits.

Deposits (Schedule of Time Ce_2

Deposits (Schedule of Time Certificates of Deposit $100 Thousand or More Maturities) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Deposits [Abstract]
Time Deposits $100,000 or More Maturing in Three Months or Less	$ 57,864
Time Deposits $100,000 or More Maturing in Three Months Through Six Months	106,574
Time Deposits $100,000 or More Maturing in Six Months Through Twelve Months	115,505
Time Deposits $100,000 or More Maturing After 12 Months	175,831
Time Deposits $100,000 or More Balance at Year End	$ 455,774

Borrowings (Narrative - Federal

Borrowings (Narrative - Federal Home Loan Bank Advances) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 1,141,464	$ 950,722
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank advances	1,141,464	950,700
Unused line of credit with Federal Home Loan Bank	40,000	40,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 535,000	$ 628,500

Borrowings (Narrative - Junior

Borrowings (Narrative - Junior Subordinated Debentures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Aug. 29, 2005
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures	$ 22,681	$ 22,681
Trust Preferred Securities [Member] | Trust I Capital Securities [Member] | Private Placement [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Amount of capital securities issued			$ 8,300
Description of variable rate basis	three-month LIBOR
Basis spread on variable rate	1.45%
Trust Preferred Securities [Member] | Trust I Debentures [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures			8,300
Description of variable rate basis	three-month LIBOR
Basis spread on variable rate	1.45%
Trust Preferred Securities [Member] | Trust II Capital Securities [Member] | Private Placement [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Amount of capital securities issued			14,400
Description of variable rate basis	three-month LIBOR
Basis spread on variable rate	1.45%
Trust Preferred Securities [Member] | Trust II Debentures [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures			$ 14,400
Description of variable rate basis	three-month LIBOR
Basis spread on variable rate	1.45%

Borrowings (Federal Home Loan B

Borrowings (Federal Home Loan Bank Advances Maturity Schedule) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Federal Home Loan Bank advances	$ 1,141,464	$ 950,722
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Scheduled Maturity, Next 12 months	974,033
Scheduled Maturity, Year Two	77,222
Scheduled Maturity, Year Three	813
Scheduled Maturity, Year Four	5,238
Scheduled Maturity, Year Five	40,900
Scheduled Maturity, Thereafter	43,258
Federal Home Loan Bank advances	$ 1,141,464	$ 950,700
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate of Amounts Due [Abstract]
Weighted Average Rate, Next 12 months	2.07%
Weighted Average Rate, Year Two	2.52%
Weighted Average Rate, Year Three	5.12%
Weighted Average Rate, Year Four	3.80%
Weighted Average Rate, Year Five	2.51%
Weighted Average Rate, Thereafter	3.29%
Weighted Average Rate, Total	2.17%

Borrowings (Certain Information

Borrowings (Certain Information of Federal Home Loan Bank of Boston Advances) (Details) - Federal Home Loan Bank of Boston [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Average amount outstanding during the period	$ 718,722	$ 484,090	$ 351,692
Amount outstanding at end of period	897,000	630,000	367,500
Highest month end balance during period	$ 897,000	$ 630,000	$ 417,500
Weighted-average interest rate at end of period	2.06%	2.67%	1.57%
Weighted-average interest rate during the period	2.59%	2.23%	1.20%

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Trust preferred securities included in Tier 1 Capital	$ 22	$ 22
Stock Repurchase Program:
Authorized amount (in shares)	850,000
Authorized amount as a percentage of total common stock	5.00%
Cumulative amount of shares purchased	0
Dividends:
Amount of additional dividends the bank could have declared	$ 257.1
Reserved Shares:
Reserved shares available for grant	1,696,991

Shareholders' Equity (Regulator

Shareholders' Equity (Regulatory Captial Requirements) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Parent Company [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital		$ 494,603	$ 455,699
Total Capital to Risk-Weighted Assets		12.94%	12.56%
Total Capital for Capital Adequacy Purposes		$ 305,728	$ 290,146
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets		8.00%	8.00%
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital		$ 467,296	$ 428,338
Tier 1 Capital to Risk Weighted-Assets		12.23%	11.81%
Tier 1 Capital Required For Capital Adequacy Purposes		$ 229,296	$ 217,609
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted-Assets		6.00%	6.00%
Common Equity Tier 1 Capital [Abstract]
Common Equity Tier 1 Capital		$ 445,298	$ 406,340
Common Equity Tier 1 Capital to Risk Weighted Assets		11.65%	11.20%
Common Equity Tier 1 Required for Capital Adequacy		$ 171,972	$ 163,207
Common Equity Tier 1 Capital for Capital Adequacy to Risk Weighted Assets		4.50%	4.50%
Tier 1 Capital (to Average Assets):
Tier 1 Leverage Capital		$ 467,296	$ 428,338
Tier 1 Leverage Capital to Average Assets	[1]	9.04%	8.89%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes		$ 206,682	$ 192,690
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	[1]	4.00%	4.00%
Bank [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital		$ 490,993	$ 453,033
Total Capital to Risk-Weighted Assets		12.85%	12.49%
Total Capital for Capital Adequacy Purposes		$ 305,693	$ 290,128
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets		8.00%	8.00%
Total Capital To Be Well Capitalized		$ 382,116	$ 362,660
Total Capital To Be Well Capitalized to Risk Weighted-Assets		10.00%	10.00%
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital		$ 463,686	$ 425,672
Tier 1 Capital to Risk Weighted-Assets		12.13%	11.74%
Tier 1 Capital Required For Capital Adequacy Purposes		$ 229,270	$ 217,596
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted-Assets		6.00%	6.00%
Tier 1 Capital Required To Be Well Capitalized		$ 305,693	$ 290,128
Tier 1 Capital Required To Be Well Capitalized to Risk Weighted-Assets		8.00%	8.00%
Common Equity Tier 1 Capital [Abstract]
Common Equity Tier 1 Capital		$ 463,686	$ 425,672
Common Equity Tier 1 Capital to Risk Weighted Assets		12.13%	11.74%
Common Equity Tier 1 Required for Capital Adequacy		$ 171,952	$ 163,197
Common Equity Tier 1 Capital for Capital Adequacy to Risk Weighted Assets		4.50%	4.50%
Common Equity Tier 1 Capital Required to be Well Capitalized		$ 248,375	$ 235,729
Common Equity Tier 1 Capital Required to be Well Capitalized to Risk Weighted Assets		6.50%	6.50%
Tier 1 Capital (to Average Assets):
Tier 1 Leverage Capital		$ 463,686	$ 425,672
Tier 1 Leverage Capital to Average Assets	[1]	8.98%	8.84%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes		$ 206,596	$ 192,652
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	[1]	4.00%	4.00%
Tier 1 Leverage Capital Required To Be Well Capitalized		$ 258,245	$ 240,815
Tier 1 Leverage Capital Required To Be Well Capitalized to Average Assets	[1]	5.00%	5.00%
[1]	Leverage ratio.

Derivative Financial Instrume_3

Derivative Financial Instruments (Narrative) (Details) $ in Thousands	Dec. 31, 2019USD ($)derivative_instrument	Dec. 31, 2018USD ($)derivative_instrument
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 60,000	$ 60,000
Interest rate swaps with customers [Member]
Derivatives, Fair Value [Line Items]
Notional amount	813,458	648,050
Mirror swaps with counterparties [Member]
Derivatives, Fair Value [Line Items]
Notional amount	813,458	648,050
Risk participation-in agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	72,866	46,510
Foreign exchange contracts [Member]
Derivatives, Fair Value [Line Items]
Notional amount	0	2,784
Interest rate lock commitments [Member]
Derivatives, Fair Value [Line Items]
Notional amount	51,439	30,766
Forward sale commitments [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 94,829	$ 61,993
Designated as Hedging Instrument [Member] | Interest rate caps [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments held | derivative_instrument	2	2
Notional amount	$ 22,700	$ 22,700
Interest rate cap strike	4.50%
Designated as Hedging Instrument [Member] | Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments held | derivative_instrument	2	2
Notional amount	$ 60,000	$ 60,000
Designated as Hedging Instrument [Member] | Interest rate floors [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments held | derivative_instrument	3	3
Notional amount	$ 300,000	$ 300,000
Interest rate floor strike	1.00%
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 813,500	648,000
Not Designated as Hedging Instrument [Member] | Mirror swaps with counterparties [Member]
Derivatives, Fair Value [Line Items]
Notional amount	813,500	648,000
Not Designated as Hedging Instrument [Member] | Risk participation-out agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	61,200	57,300
Not Designated as Hedging Instrument [Member] | Risk participation-in agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 72,900	46,500
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts [Member]
Derivatives, Fair Value [Line Items]
Notional amount		$ 2,800

Derivative Financial Instrume_4

Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Interest rate caps [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value		$ 0	$ 20
Interest rate caps [Member] | Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value		0	0
Interest rate swaps [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value		0	903
Interest rate swaps [Member] | Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value		730	0
Interest rate floors [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value		3	37
Interest rate floors [Member] | Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value		0	0
Interest rate swaps with customers [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		27,736	5,340
Interest rate swaps with customers [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		358	7,719
Mirror swaps with counterparties [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		351	7,592
Mirror swaps with counterparties [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		27,819	5,392
Risk participation agreements [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		1	0
Risk participation agreements [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		1	0
Foreign exchange contracts [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		0	0
Foreign exchange contracts [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		0	7
Interest rate lock commitments [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		1,097	806
Interest rate lock commitments [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		0	0
Forward sale commitments [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments		30	0
Forward sale commitments [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments		827	816
Derivative assets [Member]
Derivatives, Fair Value [Line Items]
Gross derivative assets		29,218	14,698
Less amounts offset in Consolidated Balance Sheets, derivative liabilities	[1]	354	10,732
Net amounts presented in Consolidated Balance Sheets, derivative assets		28,864	3,966
Less collateral pledged, derivatives assets	[2]	0	0
Net amounts		28,864	3,966
Derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross derivative liabilities		29,735	13,934
Less amounts offset in Consolidated Balance Sheets, derivative assets	[1]	354	10,732
Net amounts presented in Consolidated Balance Sheets, derivative liabilities		29,381	3,202
Less collateral pledged, derivative liabilities	[2]	27,105	1,460
Net amounts		$ 2,276	$ 1,742
[1]	Interest rate risk management contracts and loan related derivative contracts with counterparties are subject to master netting arrangements.
[2]	Collateral pledged to derivative counterparties is in the form of cash. Washington Trust may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions.

Derivative Financial Instrume_5

Derivative Financial Instruments (Derivatives in Cash Flow Hedging Relationships, Effect in Statements of Changes in Shareholders' Equity and Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	$ (984)	$ 619	$ (52)
Other Comprehensive Income (Loss) [Member] | Interest rate caps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	52	30	(64)
Other Comprehensive Income (Loss) [Member] | Interest rate swaps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	(1,232)	515	358
Other Comprehensive Income (Loss) [Member] | Interest rate floors [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	$ 196	$ 74	$ (346)

Derivative Financial Instrume_6

Derivative Financial Instruments (Derivatives not Designated as Hedging Instruments, Effect in Statements of Income) (Details) - Not Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 2,464	$ 3,319	$ 2,786
Interest rate swaps with customers [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	29,910	(290)	2,243
Mirror swaps with counterparties [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(26,043)	2,709	1,198
Risk participation agreements [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	97	(27)	(233)
Foreign exchange contracts [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	28	69	6
Interest rate lock commitments [Member] | Mortgage banking revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	290	(139)	(100)
Forward sale commitments [Member] | Mortgage banking revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ (1,818)	$ 997	$ (328)

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Write-down valuation adjustment on OREO	$ 1,000	$ 1,000
Mortgage Loans Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in fair value of mortgage loans held for sale under fair value option	167	(45)
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Allowance for loan loss on collateral dependent impaired loans	$ 871	$ 24

Fair Value Measurements (Mortga

Fair Value Measurements (Mortgage Loans Held For Sale, Fair Value Option) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Aggregate fair value	$ 27,833	$ 20,996
Aggregate principal balance	27,168	20,498
Difference between fair value and principal balance	$ 665	$ 498

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	$ 899,490	$ 927,810
Mortgage loans held for sale, fair value	27,833	20,996
Contingent consideration liability	0	0	$ 1,404
Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	157,648	242,683
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	719,080	660,793
Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		937
Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	12,579	11,772
Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	10,183	11,625
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value	27,833	20,996
Derivative assets	28,864	3,966
Total assets at fair value on a recurring basis	956,187	952,772
Derivative liabilities	29,381	3,202
Total liabilities at fair value on a recurring basis	29,381	3,202
Recurring [Member] | Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	157,648	242,683
Recurring [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	719,080	660,793
Recurring [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		937
Recurring [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	12,579	11,772
Recurring [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	10,183	11,625
Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value	0	0
Derivative assets	0	0
Total assets at fair value on a recurring basis	0	0
Derivative liabilities	0	0
Total liabilities at fair value on a recurring basis	0	0
Recurring [Member] | Level 1 [Member] | Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 1 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 1 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0
Recurring [Member] | Level 1 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 1 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value	27,833	20,996
Derivative assets	28,864	3,966
Total assets at fair value on a recurring basis	956,187	952,772
Derivative liabilities	29,381	3,202
Total liabilities at fair value on a recurring basis	29,381	3,202
Recurring [Member] | Level 2 [Member] | Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	157,648	242,683
Recurring [Member] | Level 2 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	719,080	660,793
Recurring [Member] | Level 2 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		937
Recurring [Member] | Level 2 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	12,579	11,772
Recurring [Member] | Level 2 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	10,183	11,625
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value	0	0
Derivative assets	0	0
Total assets at fair value on a recurring basis	0	0
Derivative liabilities	0	0
Total liabilities at fair value on a recurring basis	0	0
Recurring [Member] | Level 3 [Member] | Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 3 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 3 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0
Recurring [Member] | Level 3 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring [Member] | Level 3 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	$ 0	$ 0

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements (Change in contingent consideration) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 0	$ 1,404
Change in fair value of contingent consideration liability	0	(187)	$ (643)
Payments	0	(1,217)
Ending Balance	$ 0	$ 0	$ 1,404

Fair Value Measurements (Asse_2

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	[1]	$ 2,257	$ 523
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		1,448	883
Property acquired through foreclosure or repossession		1,109	2,142
Total assets at fair value on a recurring basis		2,557	3,025
Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		0	0
Property acquired through foreclosure or repossession		0	0
Total assets at fair value on a recurring basis		0	0
Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		0	0
Property acquired through foreclosure or repossession		0	0
Total assets at fair value on a recurring basis		0	0
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		1,448	883
Property acquired through foreclosure or repossession		1,109	2,142
Total assets at fair value on a recurring basis		$ 2,557	$ 3,025
[1]	The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest.

Fair Value Measurements (Qualit

Fair Value Measurements (Qualitative Information About Level 3 Assets Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans	[1]	$ 2,257	$ 523
Nonrecurring [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans		1,448	883
Property acquired through foreclosure or repossession		1,109	2,142
Nonrecurring [Member] | Level 3 [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans		1,448	883
Property acquired through foreclosure or repossession		$ 1,109	$ 2,142
Collateral Dependent Impaired Loans [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Minimum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		0.00%	0.00%
Appraisal adjustments		0.00%	0.00%
Collateral Dependent Impaired Loans [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Maximum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		20.00%	10.00%
Appraisal adjustments		100.00%	100.00%
Collateral Dependent Impaired Loans [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Weighted Average [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		5.00%	10.00%
Appraisal adjustments		67.00%	2.00%
Property Acquired Through Foreclosure Or Repossession [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Minimum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		12.00%	13.00%
Appraisal adjustments		22.00%	12.00%
Property Acquired Through Foreclosure Or Repossession [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Maximum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		12.00%	13.00%
Appraisal adjustments		22.00%	28.00%
Property Acquired Through Foreclosure Or Repossession [Member] | Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Weighted Average [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		12.00%	13.00%
Appraisal adjustments		22.00%	20.00%
[1]	The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest.

Fair Value Measurements (Carryi

Fair Value Measurements (Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands		Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost		$ 0	$ 10,415
Loans, net of allowance of loan losses		3,865,985	3,653,288
Time deposits	[1]	1,069,323	1,255,108
FHLB advances		1,141,464	950,722
Junior subordinated debentures		22,681	22,681
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost			10,415
Loans, net of allowance of loan losses		3,865,985	3,653,288
Time deposits		1,069,323	1,255,108
FHLB advances		1,141,464	950,722
Junior subordinated debentures		22,681	22,681
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost			10,316
Loans, net of allowance of loan losses		3,869,192	3,598,025
Time deposits		1,082,830	1,269,433
FHLB advances		1,145,242	950,691
Junior subordinated debentures		19,628	19,226
Estimate of Fair Value Measurement [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost			0
Loans, net of allowance of loan losses		0	0
Time deposits		0	0
FHLB advances		0	0
Junior subordinated debentures		0	0
Estimate of Fair Value Measurement [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost			10,316
Loans, net of allowance of loan losses		0	0
Time deposits		1,082,830	1,269,433
FHLB advances		1,145,242	950,691
Junior subordinated debentures		19,628	19,226
Estimate of Fair Value Measurement [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities, amortized cost			0
Loans, net of allowance of loan losses		3,869,192	3,598,025
Time deposits		0	0
FHLB advances		0	0
Junior subordinated debentures		$ 0	$ 0
[1]	Includes wholesale brokered time deposits.

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Receivables	$ 4,500	$ 4,800
Contract cost assets	$ 905	$ 458

Revenue from Contracts with C_4

Revenue from Contracts with Customers (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Net interest income		$ 31,994	$ 32,978	$ 33,858	$ 34,584	$ 33,878	$ 33,449	$ 33,111	$ 31,852	$ 133,414	[1]	$ 132,290	[1]	$ 119,531	[1]
Asset-based wealth management revenues	[1]									35,806		37,343		38,125
Transaction-based wealth management revenues	[1]									1,042		998		1,221
Total wealth management revenues	[1]									36,848		38,341		39,346
Mortgage banking revenues	[1]									14,795		10,381		11,392
Card interchange fees	[1]									4,214		3,768		3,502
Service charges on deposit accounts	[1]									3,684		3,628		3,672
Loan related derivative income	[1]									3,993		2,461		3,214
Income from bank-owned life insurance	[1]									2,354		2,196		2,161
Net realized losses on securities	[1]									(53)		0		0
Other income	[1]									1,245		1,339		1,522
Total noninterest income		$ 16,618	$ 18,342	$ 16,753	$ 15,367	$ 15,163	$ 15,215	$ 15,993	$ 15,743	67,080	[1]	62,114	[1]	64,809	[1]
Total revenues	[1]									200,494		194,404		184,340
Revenues from contracts with customers										45,930		47,066		47,989
Net Interest Income [Member]
Revenues from contracts with customers	[2]									0		0		0
Asset-based Wealth Management Revenues [Member]
Revenues from contracts with customers	[2]									35,806		37,343		38,125
Transaction-based Wealth Management Revenues [Member]
Revenues from contracts with customers	[2]									1,042		998		1,221
Investment Advisory, Management and Administrative Service [Member]
Revenues from contracts with customers	[2]									36,848		38,341		39,346
Mortgage Banking [Member]
Revenues from contracts with customers	[2]									0		0		0
Card Interchange Fees [Member]
Revenues from contracts with customers	[2]									4,214		3,768		3,502
Deposit Account [Member]
Revenues from contracts with customers	[2]									3,684		3,628		3,672
Loan Related Derivative Income [Member]
Revenues from contracts with customers	[2]									0		0		0
Income From Bank-owned Life Insurance [Member]
Revenues from contracts with customers	[2]									0		0		0
Net Realized Gain (Loss) on Securities [Member]
Revenues from contracts with customers	[2]									0		0		0
Other Noninterest Income [Member]
Revenues from contracts with customers	[2]									1,184		1,329		1,469
Total noninterest income in scope of Topic 606 [Member]
Revenues from contracts with customers	[2]									45,930		47,066		47,989
Total revenues in scope of Topic 606 [Member]
Revenues from contracts with customers	[2]									$ 45,930		$ 47,066		$ 47,989
[1]	As reported in the Consolidated Statements of Income.
[2]	Revenue from contracts with customers in scope of ASC 606.

Revenue from Contract with Cust

Revenue from Contract with Customers (Disaggregation by Timing of Revenue Recognition) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from contracts with customers		$ 45,930	$ 47,066	$ 47,989
Investment Advisory, Management and Administrative Service [Member]
Revenues from contracts with customers	[1]	36,848	38,341	39,346
Investment Advisory, Management and Administrative Service [Member] | Transferred over Time [Member]
Revenues from contracts with customers		36,848	38,341	39,346
Card Interchange Fees [Member]
Revenues from contracts with customers	[1]	4,214	3,768	3,502
Card Interchange Fees [Member] | Transferred at Point in Time [Member]
Revenues from contracts with customers		4,214	3,768	3,502
Deposit Account [Member]
Revenues from contracts with customers	[1]	3,684	3,628	3,672
Deposit Account [Member] | Transferred at Point in Time [Member]
Revenues from contracts with customers		2,850	2,802	2,899
Deposit Account [Member] | Transferred over Time [Member]
Revenues from contracts with customers		834	826	773
Other Noninterest Income [Member]
Revenues from contracts with customers	[1]	1,184	1,329	1,469
Other Noninterest Income [Member] | Transferred at Point in Time [Member]
Revenues from contracts with customers		989	958	1,122
Other Noninterest Income [Member] | Transferred over Time [Member]
Revenues from contracts with customers		$ 195	$ 371	$ 347
[1]	Revenue from contracts with customers in scope of ASC 606.

Employee Benefits (Narrative) (

Employee Benefits (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended			120 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution amounts	$ 2,700	$ 2,500	$ 2,300
Other incentive-based compensation expense	16,700	16,100	$ 16,900
Deferred compensation plan, accrued liability	$ 17,900	15,700
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution	3.00%
Qualified Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded (unfunded) status at end of period	$ 10,608	12,800
Accumulated benefit obligation	76,600	67,400
Estimated amortization of prior service cost (credit) from accumulated other comprehensive loss into net period benefit cost, next year	0
Estimated amortization of (gain) loss from accumulated other comprehensive loss into net period benefit cost, next year	$ 1,600
Fair value of equity securities, maximum percentage held by a single issuer	10.00%
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded (unfunded) status at end of period	$ (16,438)	(14,626)
Available-for-sale securities and other short-term investments, rabbi trusts	14,300	14,600
Accumulated benefit obligation	14,900	$ 13,200
Estimated amortization of prior service cost (credit) from accumulated other comprehensive loss into net period benefit cost, next year	0
Estimated amortization of (gain) loss from accumulated other comprehensive loss into net period benefit cost, next year	559
Estimated future employer contributions in next fiscal year	$ 898
Non-elective Employer Contribution [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution	4.00%
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Transition Period Pension Plan Amendment				10 years

Employee Benefits (Schedule of

Employee Benefits (Schedule of Net Funded (Unfunded) Status) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Qualified Pension Plan [Member]
Change in Benefit Obligation:
Benefit obligation at beginning of period		$ 73,380	$ 80,723
Service cost	[1]	2,037	2,244	$ 2,149
Interest cost	[2]	2,967	2,715	2,673
Actuarial (gain) loss		10,453	(7,830)
Benefits paid		(5,546)	(4,344)
Administrative expenses		(150)	(128)
Benefit obligation at end of period		83,141	73,380	80,723
Change in Plan Assets:
Fair value of plan assets at beginning of period		86,180	87,364
Actual return on plan assets		13,265	288
Employer contributions		0	3,000
Benefits paid		(5,546)	(4,344)
Administrative expenses		(150)	(128)
Fair value of plan assets at end of period		93,749	86,180	87,364
Funded (unfunded) status at end of period		10,608	12,800
Non-Qualified Retirement Plans [Member]
Change in Benefit Obligation:
Benefit obligation at beginning of period		14,626	15,203
Service cost	[1]	126	108	129
Interest cost	[2]	563	475	428
Actuarial (gain) loss		2,028	(252)
Benefits paid		(905)	(908)
Administrative expenses		0	0
Benefit obligation at end of period		16,438	14,626	15,203
Change in Plan Assets:
Fair value of plan assets at beginning of period		0	0
Actual return on plan assets		0	0
Employer contributions		905	908
Benefits paid		(905)	(908)
Administrative expenses		0	0
Fair value of plan assets at end of period		0	0	$ 0
Funded (unfunded) status at end of period		$ (16,438)	$ (14,626)
[1]	Included in salaries and employee benefits expense in the Consolidated Statements of Income.
[2]	Included in other expenses in the Consolidated Statements of Income.

Employee Benefits (Components o

Employee Benefits (Components of Accumulated Other Comprehensive Income(Loss)) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Qualified Pension Plan [Member]
Components of Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net actuarial loss	$ 10,343	$ 9,453
Prior service credit	0	(16)
Total pre-tax amounts recognized in accumulated other comprehensive income	10,343	9,437
Non-Qualified Retirement Plans [Member]
Components of Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net actuarial loss	7,405	5,785
Prior service credit	0	0
Total pre-tax amounts recognized in accumulated other comprehensive income	$ 7,405	$ 5,785

Employee Benefits (Components_2

Employee Benefits (Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net loss (gain)		$ 3,710	$ (3,098)	$ 1,591
Prior service credit	[1]	(12)	(18)	(15)
Recognized in other comprehensive income (loss)		(2,526)	4,981	(154)
Qualified Pension Plan [Member]
Net Periodic Benefit Cost:
Service cost	[2]	2,037	2,244	2,149
Interest cost	[3]	2,967	2,715	2,673
Expected return on plan assets	[3]	(4,495)	(5,272)	(4,942)
Amortization of prior service credit	[3]	(16)	(23)	(23)
Recognized net actuarial loss	[3]	792	1,496	1,114
Net periodic benefit cost		1,285	1,160	971
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net loss (gain)		890	(4,342)	(1,798)
Prior service credit		16	23	23
Recognized in other comprehensive income (loss)		906	(4,319)	(1,775)
Total recognized in net periodic benefit cost and other comprehensive income (loss)		2,191	(3,159)	(804)
Non-Qualified Retirement Plans [Member]
Net Periodic Benefit Cost:
Service cost	[2]	126	108	129
Interest cost	[3]	563	475	428
Expected return on plan assets	[3]	0	0	0
Amortization of prior service credit	[3]	0	(1)	(1)
Recognized net actuarial loss	[3]	408	411	347
Net periodic benefit cost		1,097	993	903
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net loss (gain)		1,620	(663)	1,928
Prior service credit		0	1	1
Recognized in other comprehensive income (loss)		1,620	(662)	1,929
Total recognized in net periodic benefit cost and other comprehensive income (loss)		$ 2,717	$ 331	$ 2,832
[1]	The pre-tax amounts are included in other expenses in the Consolidated Statements of Income.
[2]	Included in salaries and employee benefits expense in the Consolidated Statements of Income.
[3]	Included in other expenses in the Consolidated Statements of Income.

Employee Benefits (Weighted-Ave

Employee Benefits (Weighted-Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Qualified Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.42%	4.38%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Equivalent single discount rate for benefit obligations	4.38%	3.69%	4.18%
Equivalent single discount rate for service cost	4.44%	3.76%	4.29%
Equivalent single discount rate for interest cost	4.12%	3.42%	3.73%
Expected long-term return on plan assets	5.75%	6.75%	6.75%
Rate of compensation increase	3.75%	3.75%	3.75%
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	3.30%	4.30%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Equivalent single discount rate for benefit obligations	4.28%	3.58%	3.96%
Equivalent single discount rate for service cost	4.48%	3.79%	4.25%
Equivalent single discount rate for interest cost	3.98%	3.22%	3.36%
Rate of compensation increase	3.75%	3.75%	3.75%

Employee Benefits (Schedule o_2

Employee Benefits (Schedule of Fair Value of Qualified Pension Plan Assets) (Details) - Qualified Pension Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 93,749	$ 86,180	$ 87,364
Asset allocations by category	100.00%	100.00%
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 52,103	$ 51,435
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	41,646	34,745
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and cash equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 9,902	$ 25,986
Asset allocations by category	10.60%	30.20%
Cash and cash equivalents [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 9,902	$ 25,986
Cash and cash equivalents [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and cash equivalents [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of U.S government-sponsored enterprises [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	28,615	21,787
Obligations of U.S government-sponsored enterprises [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of U.S government-sponsored enterprises [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	28,615	21,787
Obligations of U.S government-sponsored enterprises [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of states and political subdivisions [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,998	2,597
Obligations of states and political subdivisions [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of states and political subdivisions [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,998	2,597
Obligations of states and political subdivisions [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10,033	10,361
Corporate bonds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	10,033	10,361
Corporate bonds [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,593	9,957
Common stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,593	9,957
Common stocks [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common stocks [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	27,608	15,492
Mutual funds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	27,608	15,492
Mutual funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual funds [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Fixed income securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations by category	44.40%	40.30%
Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Asset allocations by category	45.00%	29.50%

Employee Benefits (Estimated Fu

Employee Benefits (Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2019USD ($)
Qualified Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Expected Future Payments, Next Twelve Months	$ 4,748
Expected Future Payments, Year Two	3,803
Expected Future Payments, Year Three	4,083
Expected Future Payments, Year Four	4,574
Expected Future Payments, Year Five	4,588
Expected Future Payments, Thereafter	27,957
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan, Expected Future Benefit Payment [Abstract]
Expected Future Payments, Next Twelve Months	898
Expected Future Payments, Year Two	887
Expected Future Payments, Year Three	878
Expected Future Payments, Year Four	876
Expected Future Payments, Year Five	871
Expected Future Payments, Thereafter	$ 4,343

Share-Based Compensation Arra_3

Share-Based Compensation Arrangements (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Apr. 23, 2013	Apr. 28, 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$ 5,000
Weighted average recognition period (in years)	2 years 3 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options exercised total intrinsic value	$ 580	$ 833	$ 1,000
Cliff vesting period (years)	3 years	3 years	3 years
Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested share units	26,070	13,430	15,900
Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested share units	43,360
Cliff vesting period (years)		3 years	3 years
Performance share awards granted, grant date fair value	$ 52.84
Performance share awards, shares vesting percentages	138.00%
Performance share awards, shares vesting	108,964
Minimum [Member] | Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)	3 years	3 years	3 years
Minimum [Member] | Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)	3 years
Maximum [Member] | Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)	5 years		5 years
Maximum [Member] | Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)	5 years
2013 Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized				1,748,250
Amended and Restated 2003 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized					1,200,000
Amended and Restated 2003 Stock Incentive Plan [Member] | Stock Options and Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized					400,000

Share-Based Compensation Arra_4

Share-Based Compensation Arrangements (Compensation Cost for Share-based Compensation Arrangements) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Payment Arrangement [Abstract]
Tax benefit from stock option exercises and other equity awards		$ 248	$ 496	$ 508
Share-based compensation expense		3,124	2,602	2,577
Related income tax benefit	[1]	$ 982	$ 1,108	$ 1,114
[1]	Includes $248 thousand , $496 thousand , and $508 thousand , respectively, of excess tax benefits recognized upon the settlement of share-based compensation awards in 2019 , 2018 and 2017 .

Share-Based Compensation Arra_5

Share-Based Compensation Arrangements (Share Options Fair Value Assumptions) (Details) - Stock Options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	61,800	47,950	47,725
Cliff vesting period (years)	3 years	3 years	3 years
Expected term (years)	6 years 6 months	6 years 6 months	7 years
Expected dividend yield	3.40%	3.39%	3.57%
Weighted average expected volatility	23.05%	22.73%	27.10%
Weighted average risk-free interest rate	1.71%	3.14%	1.70%
Weighted average grant-date fair value	$ 7.44	$ 9.74	$ 10.60

Share-Based Compensation Arra_6

Share-Based Compensation Arrangements (Share Options Activity) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Number of Share Options:
Beginning of period	222,615
Granted	61,800	47,950	47,725
Exercised	(35,600)
Forfeited or expired	0
End of period	248,815	222,615
Options exercisable	95,240
Options expected to vest in future periods	153,575
Weighted Average Exercise Price (in dollars per share):
Beginning of period	$ 42.92
Granted	48.65
Exercised	35.70
Forfeited or expired	0
End of period	45.38	$ 42.92
Options exercisable	33.57
Options expected to vest in future periods	$ 52.70
Outstanding Weighted Average Remaining Contractual Term	7 years 3 months 7 days
Exercisable Weighted Average Remaining Contractual Term	4 years 8 months 15 days
Expected to Vest Weighted Average Remaining Contractual Term	8 years 10 months 6 days
Outstanding Aggregate Intrinsic Value	$ 2,308
Exercisable Aggregate Intrinsic Value	1,926
Expected to Vest Aggregate Intrinsic Value	$ 382

Share-Based Compensation Arra_7

Share-Based Compensation Arrangements (Stock Options Outstanding and Options Exercisable) (Details)	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options Outstanding, Number of Share Options | shares	248,815
Options Outstanding, Weighted Average Remaining Life (Years)	7 years 3 months 7 days
Options Outstanding, Weighted Average Exercise Price	$ 45.38
Options Exercisable, Number of Share Options | shares	95,240
Options Exercisable, Weighted Average Exercise Price	$ 33.57
$15.01 to $20.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	15.01
Exercise Price Ranges, Upper Range Limit	$ 20
Options Outstanding, Number of Share Options | shares	4,100
Options Outstanding, Weighted Average Remaining Life (Years)	5 months 1 day
Options Outstanding, Weighted Average Exercise Price	$ 17.52
Options Exercisable, Number of Share Options | shares	4,100
Options Exercisable, Weighted Average Exercise Price	$ 17.52
$20.01 to $25.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	20.01
Exercise Price Ranges, Upper Range Limit	$ 25
Options Outstanding, Number of Share Options | shares	22,015
Options Outstanding, Weighted Average Remaining Life (Years)	2 years 1 month 20 days
Options Outstanding, Weighted Average Exercise Price	$ 22.89
Options Exercisable, Number of Share Options | shares	22,015
Options Exercisable, Weighted Average Exercise Price	$ 22.89
$25.01 to $30.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	25.01
Exercise Price Ranges, Upper Range Limit	$ 30
Options Outstanding, Number of Share Options | shares	0
Options Outstanding, Weighted Average Remaining Life (Years)	0 years
Options Outstanding, Weighted Average Exercise Price	$ 0
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0
$30.01 to $35.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	30.01
Exercise Price Ranges, Upper Range Limit	$ 35
Options Outstanding, Number of Share Options | shares	19,775
Options Outstanding, Weighted Average Remaining Life (Years)	4 years 1 month 28 days
Options Outstanding, Weighted Average Exercise Price	$ 32.76
Options Exercisable, Number of Share Options | shares	19,775
Options Exercisable, Weighted Average Exercise Price	$ 32.76
$35.01 to $40.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	35.01
Exercise Price Ranges, Upper Range Limit	$ 40
Options Outstanding, Number of Share Options | shares	22,100
Options Outstanding, Weighted Average Remaining Life (Years)	5 years 8 months 19 days
Options Outstanding, Weighted Average Exercise Price	$ 39.22
Options Exercisable, Number of Share Options | shares	18,100
Options Exercisable, Weighted Average Exercise Price	$ 39.55
$40.01 to $45.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	40.01
Exercise Price Ranges, Upper Range Limit	$ 45
Options Outstanding, Number of Share Options | shares	31,250
Options Outstanding, Weighted Average Remaining Life (Years)	6 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 40.25
Options Exercisable, Number of Share Options | shares	31,250
Options Exercisable, Weighted Average Exercise Price	$ 40.25
$45.01 to $50.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	45.01
Exercise Price Ranges, Upper Range Limit	$ 50
Options Outstanding, Number of Share Options | shares	61,800
Options Outstanding, Weighted Average Remaining Life (Years)	9 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 48.65
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0
$50.01 to $55.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	50.01
Exercise Price Ranges, Upper Range Limit	$ 55
Options Outstanding, Number of Share Options | shares	47,950
Options Outstanding, Weighted Average Remaining Life (Years)	8 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 54.74
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0
$55.01 to $60.00 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	55.01
Exercise Price Ranges, Upper Range Limit	$ 60
Options Outstanding, Number of Share Options | shares	39,825
Options Outstanding, Weighted Average Remaining Life (Years)	7 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 58.05
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0

Share-Based Compensation Arra_8

Share-Based Compensation Arrangements (Nonvested Share Units Activity) (Details) - Time Based Nonvested Shares [Member] - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Number of Shares:
Beginning of period	45,350
Granted	26,070	13,430	15,900
Vested	(17,530)
Forfeited	0
End of period	53,890	45,350
Weighted Average Grant Date Fair Value (in dollars per share):
Beginning of period	$ 48.73
Granted	49.81
Vested	40.26
Forfeited	0
End of period	$ 52.01	$ 48.73

Share-Based Compensation Arra_9

Share-Based Compensation Arrangements (Nonvested Performance Share Unit Awards Outstanding) (Details) - Performance Based Nonvested Shares [Member]	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 52.84
Performance share awards, shares vesting percentages	138.00%
Performance share awards, shares vesting	108,964
2019 Grant [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards, shares vesting	43,360
2018 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 54.25
Performance share awards, shares vesting percentages	140.00%
Performance share awards, shares vesting	41,454
2016 Grant [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 51.85
Performance share awards, shares vesting percentages	150.00%
Performance share awards, shares vesting	24,150

Share-Based Compensation Arr_10

Share-Based Compensation Arrangements (Nonvested Performance Share Units Activity) (Details) - Performance Based Nonvested Shares [Member]	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Number of Shares:
Beginning of period | shares	93,604
Granted | shares	43,360
Vested | shares	(28,239)
Forfeited | shares	239
End of period | shares	108,964
Weighted Average Grant Date Fair Value (in dollars per share):
Beginning of period | $ / shares	$ 48.20
Granted | $ / shares	52.84
Vested | $ / shares	36.11
Forfeited | $ / shares	36.11
End of period | $ / shares	$ 53.16

Business Segments (Statement of

Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Segment Reporting Information [Line Items]
Net interest income (expense)	$ 31,994	$ 32,978	$ 33,858	$ 34,584	$ 33,878	$ 33,449	$ 33,111	$ 31,852	$ 133,414	[1]	$ 132,290	[1]	$ 119,531	[1]
Provision for loan losses	0	400	525	650	800	350	400	0	1,575		1,550		2,600
Net interest income (expense) after provision for loan losses	31,994	32,578	33,333	33,934	33,078	33,099	32,711	31,852	131,839		130,740		116,931
Noninterest income	16,618	18,342	16,753	15,367	15,163	15,215	15,993	15,743	67,080	[1]	62,114	[1]	64,809	[1]
Depreciation and amortization expense									4,234		4,261		4,489
Other noninterest expenses									106,506		101,901		99,611
Total noninterest expense	28,755	26,870	28,151	26,964	26,682	26,062	26,288	27,130	110,740		106,162		104,100
Income before income taxes	19,857	24,050	21,935	22,337	21,559	22,252	22,416	20,465	88,179		86,692		77,640
Income tax expense	4,321	5,236	4,662	4,842	4,523	4,741	4,742	4,254	19,061		18,260		31,715
Net income	15,536	$ 18,814	$ 17,273	$ 17,495	17,036	$ 17,511	$ 17,674	$ 16,211	69,118		68,432		45,925
Total assets at period end	5,292,659				5,010,766				5,292,659		5,010,766		4,529,850
Expenditures for long-lived assets									3,132		3,974		2,779
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									112,414		106,668		98,736
Provision for loan losses									1,575		1,550		2,600
Net interest income (expense) after provision for loan losses									110,839		105,118		96,136
Noninterest income									27,857		21,509		23,244
Depreciation and amortization expense									2,630		2,589		2,604
Other noninterest expenses									66,517		62,673		60,828
Total noninterest expense									69,147		65,262		63,432
Income before income taxes									69,549		61,365		55,948
Income tax expense									15,189		13,149		23,876
Net income									54,360		48,216		32,072
Total assets at period end	4,070,594				3,804,021				4,070,594		3,804,021		3,491,845
Expenditures for long-lived assets									2,521		3,415		2,224
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									(438)		(334)		(167)
Provision for loan losses									0		0		0
Net interest income (expense) after provision for loan losses									(438)		(334)		(167)
Noninterest income									36,856		38,341		39,346
Depreciation and amortization expense									1,445		1,501		1,689
Other noninterest expenses									26,057		26,222		26,718
Total noninterest expense									27,502		27,723		28,407
Income before income taxes									8,916		10,284		10,772
Income tax expense									2,308		2,577		3,795
Net income									6,608		7,707		6,977
Total assets at period end	74,990				71,254				74,990		71,254		66,083
Expenditures for long-lived assets									445		407		360
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									21,438		25,956		20,962
Provision for loan losses									0		0		0
Net interest income (expense) after provision for loan losses									21,438		25,956		20,962
Noninterest income									2,367		2,264		2,219
Depreciation and amortization expense									159		171		196
Other noninterest expenses									13,932		13,006		12,065
Total noninterest expense									14,091		13,177		12,261
Income before income taxes									9,714		15,043		10,920
Income tax expense									1,564		2,534		4,044
Net income									8,150		12,509		6,876
Total assets at period end	$ 1,147,075				$ 1,135,491				1,147,075		1,135,491		971,922
Expenditures for long-lived assets									$ 166		$ 152		$ 195
[1]	As reported in the Consolidated Statements of Income.

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Change in fair value of securities available for sale, before tax		$ 26,074		$ (12,063)	$ 986
Change in fair value of securities available for sale, tax		6,127		(2,835)	365
Change is fair value of securities available for sale		19,947		(9,228)	621
Net (gains) losses on securities classified into earnings, before tax		53	[1]	0	0
Net (gains) losses on securities classified into earnings, tax		12	[1]	0	0
Net (gains) losses on securities classified into earnings		41	[1]	0	0
Net change in fair value of securities available for sale, before tax		26,127		(12,063)	986
Net change in fair value of securities available for sale, tax		6,139		(2,835)	365
Net change in fair value of securities available for sale		19,988		(9,228)	621
Net change in fair value of cash flow hedges, before tax		(1,444)		639	(774)
Net change in fair value of cash flow hedges, tax		(339)		151	(223)
Change in fair value of cash flow hedges		(1,105)		488	(551)
Net cash flow hedge losses reclassified into earnings, before tax	[2]	159		170	792
Net cash flow hedge losses reclassified into earnings, tax	[2]	38		39	293
Net cash flow hedge losses reclassified into earnings	[2]	121		131	499
Change in fair value of cash flow hedges, before tax		(1,285)		809	18
Change in fair value of cash flow hedges, tax		(301)		190	70
Net change in fair value of cash flow hedges		(984)		619	(52)
Defined benefit plan obligation adjustment, before tax		(3,710)		3,098	(1,591)
Defined benefit plan obligation adjustment, tax		(872)		729	(594)
Defined benefit plan obligation adjustment		(2,838)		2,369	(997)
Amortization of net actuarial losses, before tax	[3]	1,200		1,907	1,461
Amortization of net actuarial losses, tax	[3]	282		448	546
Amortization of net actuarial losses	[3]	918		1,459	915
Amortization of net prior service credits, before tax	[3]	(16)		(24)	(24)
Amortization of net prior service credits, tax	[3]	(4)		(6)	(9)
Amortization of net prior service credits	[3]	(12)		(18)	(15)
Net change in defined benefit plan obligations, before tax		(2,526)		4,981	(154)
Net change in defined benefit plan obligations, tax		(594)		1,171	(57)
Net change in defined benefit plan obligations		(1,932)		3,810	(97)
Total other comprehensive income (loss), before tax		22,316		(6,273)	850
Total other comprehensive income (loss), tax		5,244		(1,474)	378
Total other comprehensive income (loss), net of tax		17,072		(4,799)	472
Net Unrealized Gains (Losses) on AFS Securities [Member]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Total other comprehensive income (loss), net of tax		$ 19,988		$ (9,228)	$ 621
[1]	The pre-tax amount is reported as net realized losses on securities in the Consolidated Statements of Income.
[2]	The pre-tax amounts are included in interest expense on FHLB advances, interest expense on junior subordinated debentures and interest and fees on loans in the Consolidated Statements of Income.
[3]	The pre-tax amounts are included in other expenses in the Consolidated Statements of Income.

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated other comprehensive income (loss), beginning balance	$ (28,309)
Net other comprehensive income (loss)	17,072	$ (4,799)	$ 472
Reclassification of income tax effects due to the adoption of ASU 2018-02			0
Accumulated other comprehensive income (loss), ending balance	(11,237)	(28,309)
Net Unrealized Gains (Losses) on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance	(16,762)	(7,534)	(6,825)
Other comprehensive income (loss) before reclassifications, net of tax	19,947	(9,228)	621
Amounts reclassified from accumulated other comprehensive income, net of tax	41	0	0
Net other comprehensive income (loss)	19,988	(9,228)	621
Reclassification of income tax effects due to the adoption of ASU 2018-02			(1,330)
Accumulated other comprehensive income (loss), ending balance	3,226	(16,762)	(7,534)
Net Unrealized Gains (Losses) on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance	191	(428)	(300)
Other comprehensive income (loss) before reclassifications, net of tax	(1,105)	488	(551)
Amounts reclassified from accumulated other comprehensive income, net of tax	121	131	499
Net other comprehensive income (loss)	(984)	619	(52)
Reclassification of income tax effects due to the adoption of ASU 2018-02			(76)
Accumulated other comprehensive income (loss), ending balance	(793)	191	(428)
Defined Benefit Pension Plan Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance	(11,738)	(15,548)	(12,632)
Other comprehensive income (loss) before reclassifications, net of tax	(2,838)	2,369	(741)
Amounts reclassified from accumulated other comprehensive income, net of tax	906	1,441	644
Net other comprehensive income (loss)	(1,932)	3,810	(97)
Reclassification of income tax effects due to the adoption of ASU 2018-02			(2,819)
Accumulated other comprehensive income (loss), ending balance	(13,670)	(11,738)	(15,548)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss), beginning balance	(28,309)	(23,510)	(19,757)
Other comprehensive income (loss) before reclassifications, net of tax	16,004	(6,371)	(671)
Amounts reclassified from accumulated other comprehensive income, net of tax	1,068	1,572	1,143
Net other comprehensive income (loss)	17,072	(4,799)	472
Reclassification of income tax effects due to the adoption of ASU 2018-02			(4,225)
Accumulated other comprehensive income (loss), ending balance	$ (11,237)	$ (28,309)	$ (23,510)

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Net income	$ 15,536	$ 18,814	$ 17,273	$ 17,495	$ 17,036	$ 17,511	$ 17,674	$ 16,211	$ 69,118	$ 68,432	$ 45,925
Less dividends and undistributed earnings allocated to participating securities									(139)	(144)	(108)
Net income available to common shareholders									$ 68,979	$ 68,288	$ 45,817
Weighted average common shares outstanding - basic	17,351,000	17,338,000	17,330,000	17,304,000	17,297,000	17,283,000	17,272,000	17,234,000	17,331,000	17,272,000	17,207,000
Basic earnings per common share (in dollars per share)	$ 0.89	$ 1.08	$ 0.99	$ 1.01	$ 0.98	$ 1.01	$ 1.02	$ 0.94	$ 3.98	$ 3.95	$ 2.66
Less dividends and undistributed earnings allocated to participating securities									$ (139)	$ (144)	$ (108)
Net income available to common shareholders	$ 15,502	$ 18,778	$ 17,238	$ 17,461	$ 17,004	$ 17,475	$ 17,636	$ 16,173	$ 68,979	$ 68,288	$ 45,817
Dilutive effect of common stock equivalents (in shares)									83,000	119,000	131,000
Weighted average common shares outstanding - diluted (in shares)	17,436,000	17,414,000	17,405,000	17,401,000	17,385,000	17,382,000	17,387,000	17,345,000	17,414,000	17,391,000	17,338,000
Diluted earnings per common share (in dollars per share)	$ 0.89	$ 1.08	$ 0.99	$ 1	$ 0.98	$ 1.01	$ 1.01	$ 0.93	$ 3.96	$ 3.93	$ 2.64
Antidilutive common stock equivalents									100,643	55,821	11,572

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019		Dec. 31, 2018	Jan. 01, 2019
Operating Lease, Weighted Average Remaining Lease Term	14 years
Lease, Cost	$ 3,773		$ 3,700
Operating lease right-of-use assets	26,792		0	$ 28,900
Operating lease liabilities	$ 28,861	[1]	$ 0	$ 30,900
Operating Lease, Weighted Average Discount Rate, Percent	3.67%
Number of operating leases not yet commenced	1
Minimum [Member]
Lease Expiration Period	4 months		5 months
Lessee, Operating Lease, Renewal Term	1 year
Maximum [Member]
Lease Expiration Period	21 years		22 years
Lessee, Operating Lease, Renewal Term	5 years
[1]	Includes short-term operating lease liabilities of $2.5 million .

Leases (Schedule of Operating L

Leases (Schedule of Operating Lease Payments) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019		Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease minimum payments, Next Twelve Months		$ 3,493
Operating lease minimum payments, Year Two		3,291
Operating lease minimum payments, Year Three		3,165
Operating lease minimum payments, Year Four		3,097
Operating lease minimum payments, Year Five		2,904
Operating lease minimum payments, Thereafter		21,818
Total operating lease payments	[1]	37,768
Less interest		8,907
Present value of operating lease liabilities		28,861	[2]	$ 30,900	$ 0
Reasonably certain to renew lease option		2,400
Short-term operating leases		$ 2,500
[1]	Includes $2.4 million related to options to extend lease terms that are reasonably certain of being exercised.
[2]	Includes short-term operating lease liabilities of $2.5 million .

Leases (Lease Cost and Cash Pai

Leases (Lease Cost and Cash Paid) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease expense		$ 3,724
Variable lease expense		49
Total lease expense		3,773	$ 3,700
Cash paid reducing operating lease liabilities	[1]	$ 3,586
[1]	Included in net occupancy expenses in the Consolidated Income Statement.

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Future minimum lease payments, Next Twelve Months		$ 3,544
Future minimum lease payments, Two Years		2,980
Future minimum lease payments, Three Years		2,677
Future minimum lease payments, Four Years		2,293
Future minimum lease payments, Five Years		2,059
Future minimum lease payments, Thereafter		22,648
Total future minimum lease payments		$ 36,201
Maximum [Member]
Lease Expiration Period	21 years	22 years
Lease Expiration Period, Renewal Option		5 years
Minimum [Member]
Lease Expiration Period	4 months	5 months
Lease Expiration Period, Renewal Option		1 year

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Line Items]
Standby letters of credit extension period	1 year
Unpaid principal balance of loans repurchased	$ 1,700	$ 1,200
Reserve for loans repurchases	170	140
Commitments to extend credit on standby letters of credit [Member] | Commitments to Extend Credit [Member]
Commitments and Contingencies Disclosure [Line Items]
Contract amount	$ 13,710	$ 7,706

Commitments and Contingencies_3

Commitments and Contingencies (Financial Instruments with Off Balance Sheet Risk) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 51,439	$ 30,766
Forward sale commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	94,829	61,993
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	813,458	648,050
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	813,458	648,050
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	72,866	46,510
Foreign exchange contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	0	2,784
Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	60,000	60,000
Commitments to Extend Credit [Member] | Commitments to extend credit on commerical loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	471,338	533,884
Commitments to Extend Credit [Member] | Commitments to extend credit on home equity lines [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	295,687	270,462
Commitments to Extend Credit [Member] | Commitments to extend credit on other loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	88,613	46,698
Commitments to Extend Credit [Member] | Commitments to extend credit on standby letters of credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	$ 13,710	$ 7,706

Parent Company Financial Stat_3

Parent Company Financial Statements (Balance Sheet) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets:
Other assets	$ 100,934	$ 77,175
Total assets	5,292,659	5,010,766	$ 4,529,850
Liabilities:
Junior subordinated debentures	22,681	22,681
Contingent consideration liability	0	0	1,404
Other liabilities	97,279	65,131
Total liabilities	4,789,167	4,562,582
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares; issued and outstanding 17,363,455 shares in 2019 and 17,302,037 in 2018	1,085	1,081
Paid-in capital	123,281	119,888
Retained earnings	390,363	355,524
Accumulated other comprehensive loss	(11,237)	(28,309)
Total shareholders’ equity	503,492	448,184	$ 413,284	$ 390,804
Total liabilities and shareholders’ equity	$ 5,292,659	$ 5,010,766
Common stock, par value (in dollars per share)	$ 0.0625	$ 0.0625
Common stock, shares authorized (in shares)	60,000,000	60,000,000
Common stock, shares issued (in shares)	17,363,455	17,302,037
Common stock, shares outstanding (in shares)	17,363,455	17,302,037
Parent Company [Member]
Assets:
Cash on deposit with bank subsidiary	$ 1,838	$ 1,912
Dividends receivable from bank subsidiary	9,575	7,762
Other assets	232	190
Total assets	535,496	479,390
Liabilities:
Junior subordinated debentures	22,681	22,681
Dividends payable	9,252	8,439
Other liabilities	71	86
Total liabilities	32,004	31,206
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares; issued and outstanding 17,363,455 shares in 2019 and 17,302,037 in 2018	1,085	1,081
Paid-in capital	123,281	119,888
Retained earnings	390,363	355,524
Accumulated other comprehensive loss	(11,237)	(28,309)
Total shareholders’ equity	503,492	448,184
Total liabilities and shareholders’ equity	535,496	479,390
Bank [Member]
Assets:
Investment in subsidiaries at equity value:	521,969	467,657
Non-bank [Member]
Assets:
Investment in subsidiaries at equity value:	$ 1,882	$ 1,869

Parent Company Financial Stat_4

Parent Company Financial Statements (Statement of Income) (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income:
Total income	[1]									$ 200,494	$ 194,404	$ 184,340
Expenses:
Interest on junior subordinated debentures										980	869	613
Legal and professional fees										2,535	2,427	2,294
Change in fair value of contingent consideration										0	(187)	(643)
Income before income taxes		$ 19,857	$ 24,050	$ 21,935	$ 22,337	$ 21,559	$ 22,252	$ 22,416	$ 20,465	88,179	86,692	77,640
Income tax benefit		(4,321)	(5,236)	(4,662)	(4,842)	(4,523)	(4,741)	(4,742)	(4,254)	(19,061)	(18,260)	(31,715)
Net income		$ 15,536	$ 18,814	$ 17,273	$ 17,495	$ 17,036	$ 17,511	$ 17,674	$ 16,211	69,118	68,432	45,925
Parent Company [Member]
Income:
Total income										36,823	32,418	27,918
Expenses:
Interest on junior subordinated debentures										980	869	613
Legal and professional fees										147	187	169
Change in fair value of contingent consideration										0	(187)	(643)
Other										337	324	298
Total expenses										1,464	1,193	437
Income before income taxes										35,359	31,225	27,481
Income tax benefit										301	284	340
Income before equity in undistributed earnings (losses) of subsidiaries										35,660	31,509	27,821
Net income										69,118	68,432	45,925
Bank [Member]
Income:
Dividends from subsidiaries										36,796	32,394	27,900
Expenses:
Equity in undistributed earnings (losses) of subsidiaries										33,445	36,876	18,193
Non-bank [Member]
Income:
Dividends from subsidiaries										27	24	18
Expenses:
Equity in undistributed earnings (losses) of subsidiaries										$ 13	$ 47	$ (89)
[1]	As reported in the Consolidated Statements of Income.

Parent Company Financial Stat_5

Parent Company Financial Statements (Statements of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income	$ 15,536	$ 18,814	$ 17,273	$ 17,495	$ 17,036	$ 17,511	$ 17,674	$ 16,211	$ 69,118	$ 68,432	$ 45,925
Adjustments to reconcile net income to net cash provided by operating activities:
(Increase) decrease in other assets									(27,961)	(7,456)	(8,794)
Change in fair value of contingent consideration liability									0	(187)	(643)
Tax benefit from stock option exercises and other equity awards									248	496	508
Net cash provided by (used in) operating activities									73,435	82,876	59,385
Cash flows from investing activities:
Net cash provided by (used in) investing activities									(160,115)	(481,831)	(179,706)
Cash flows from financing activities:
Payment of contingent consideration liability									0	(1,217)	0
Net proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered									273	(671)	366
Cash dividends paid									(34,189)	(29,312)	(26,300)
Net cash provided by (used in) financing activities									131,660	409,507	95,447
Net increase (decrease) in cash and cash equivalents									44,980	10,552	(24,874)
Cash and cash equivalents at beginning of year				93,475	93,475			82,923	93,475	82,923	107,797
Cash and cash equivalents at end of year	138,455				93,475	$ 93,475			138,455	93,475	82,923
Parent Company [Member]
Cash flows from operating activities:
Net income									69,118	68,432	45,925
Adjustments to reconcile net income to net cash provided by operating activities:
(Increase) decrease in dividend receivable									(1,813)	8	(1,252)
(Increase) decrease in other assets									(43)	70	72
Increase (decrease) in accrued expenses and other liabilities									(15)	17	22
Change in fair value of contingent consideration liability									0	(187)	(643)
Tax benefit from stock option exercises and other equity awards									248	496	508
Other, net									(195)	(465)	(673)
Net cash provided by (used in) operating activities									33,842	31,448	25,855
Cash flows from financing activities:
Payment of contingent consideration liability									0	(1,217)	0
Net proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered									273	(671)	366
Cash dividends paid									(34,189)	(29,312)	(26,300)
Net cash provided by (used in) financing activities									(33,916)	(31,200)	(25,934)
Net increase (decrease) in cash and cash equivalents									(74)	248	(79)
Cash and cash equivalents at beginning of year				$ 1,912				$ 1,664	1,912	1,664	1,743
Cash and cash equivalents at end of year	$ 1,838				$ 1,912				1,838	1,912	1,664
Bank [Member]
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings (losses) of subsidiaries									(33,445)	(36,876)	(18,193)
Non-bank [Member]
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings (losses) of subsidiaries									$ (13)	$ (47)	$ 89

Selected Quarterly Consolidat_3

Selected Quarterly Consolidated Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interest and dividend income	$ 47,383	$ 49,527	$ 50,559	$ 50,194	$ 47,517	$ 45,164	$ 43,286	$ 40,440	$ 197,663		$ 176,407		$ 149,586
Interest expense	15,389	16,549	16,701	15,610	13,639	11,715	10,175	8,588	64,249		44,117		30,055
Net interest income	31,994	32,978	33,858	34,584	33,878	33,449	33,111	31,852	133,414	[1]	132,290	[1]	119,531	[1]
Provision for loan losses	0	400	525	650	800	350	400	0	1,575		1,550		2,600
Net interest income after provision for loan losses	31,994	32,578	33,333	33,934	33,078	33,099	32,711	31,852	131,839		130,740		116,931
Noninterest income	16,618	18,342	16,753	15,367	15,163	15,215	15,993	15,743	67,080	[1]	62,114	[1]	64,809	[1]
Noninterest expense	28,755	26,870	28,151	26,964	26,682	26,062	26,288	27,130	110,740		106,162		104,100
Income before income taxes	19,857	24,050	21,935	22,337	21,559	22,252	22,416	20,465	88,179		86,692		77,640
Income tax expense	4,321	5,236	4,662	4,842	4,523	4,741	4,742	4,254	19,061		18,260		31,715
Net income	15,536	18,814	17,273	17,495	17,036	17,511	17,674	16,211	69,118		68,432		45,925
Net income available to common shareholders	$ 15,502	$ 18,778	$ 17,238	$ 17,461	$ 17,004	$ 17,475	$ 17,636	$ 16,173	$ 68,979		$ 68,288		$ 45,817
Weighted average common shares outstanding - basic	17,351	17,338	17,330	17,304	17,297	17,283	17,272	17,234	17,331		17,272		17,207
Weighted average common shares outstanding - diluted	17,436	17,414	17,405	17,401	17,385	17,382	17,387	17,345	17,414		17,391		17,338
Basic earnings per common share (in dollars per share)	$ 0.89	$ 1.08	$ 0.99	$ 1.01	$ 0.98	$ 1.01	$ 1.02	$ 0.94	$ 3.98		$ 3.95		$ 2.66
Diluted earnings per common share (in dollars per share)	0.89	1.08	0.99	1	0.98	1.01	1.01	0.93	3.96		3.93		2.64
Cash dividends declared per share (in dollars per share)	$ 0.51	$ 0.51	$ 0.51	$ 0.47	$ 0.47	$ 0.43	$ 0.43	$ 0.43	$ 2		$ 1.76		$ 1.54
[1]	As reported in the Consolidated Statements of Income.