Washington Trust Bancorp (WASH) 10-Q 4 Nov 19 2019 Q3 Quarterly report Financial data

Cover Page

Cover Page - shares	9 Months Ended
	Sep. 30, 2019	Oct. 31, 2019
Cover page.
Entity Address, Address Line One	23 Broad Street
Entity Address, City or Town	Westerly,
Entity Address, State or Province	RI
Entity Incorporation, State or Country Code	RI
Document Transition Report	false
Document Quarterly Report	true
Entity Registrant Name	Washington Trust Bancorp Inc
Entity Central Index Key	0000737468
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Entity File Number	001-32991
City Area Code	401
Local Phone Number	348-1200
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Title of 12(g) Security	COMMON STOCK, $.0625 PAR VALUE PER SHARE
Trading Symbol	WASH
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		17,350,703
Entity Tax Identification Number	05-0404671
Entity Address, Postal Zip Code	02891

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands		Sep. 30, 2019		Dec. 31, 2018
Assets:
Cash and due from banks		$ 141,768		$ 89,923
Short-term investments		4,336		3,552
Mortgage loans held for sale		44,657		20,996
Securities:
Available for sale debt securities, at fair value		887,020		927,810
Held to maturity debt securities, at amortized cost		0		10,415
Total securities		887,020		938,225
Federal Home Loan Bank stock, at cost		45,030		46,068
Loans:
Total loans	[1]	3,778,106		3,680,360
Less allowance for loan losses		26,997		27,072
Net loans		3,751,109		3,653,288
Premises and equipment, net		29,293		29,005
Operating lease right-of-use assets		27,500		0
Investment in bank-owned life insurance		81,920		80,463
Goodwill		63,909		63,909
Identifiable intangible assets, net		7,448		8,162
Other assets		114,888		77,175
Total assets		5,198,878		5,010,766
Liabilities:
Noninterest-bearing deposits		619,839		603,216
Interest-bearing deposits		2,966,314		2,920,832
Total deposits		3,586,153		3,524,048
Federal Home Loan Bank advances		956,786		950,722
Junior subordinated debentures		22,681		22,681
Operating lease liabilities		29,541	[2]	0
Other liabilities		105,892		65,131
Total liabilities		4,701,053		4,562,582
Commitments and contingencies (Note 18)
Shareholders' Equity:
Common stock		1,084		1,081
Paid-in capital		121,900		119,888
Retained earnings		383,765		355,524
Unrealized losses on held to maturity securities, net of tax		(8,924)		(28,309)
Total shareholders' equity		497,825		448,184
Total liabilities and shareholders’ equity		$ 5,198,878		$ 5,010,766
[1]	Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 .
[2]	Includes short-term operating lease liabilities of $2.3 million .

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Held to maturity debt securities, fair value	$ 0	$ 10,316
Common stock, par value	$ 0.0625	$ 0.0625
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares issued	17,338,348	17,302,037
Common stock, shares outstanding	17,338,348	17,302,037

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Interest income:
Interest and fees on loans	$ 41,558	$ 38,493	$ 125,440	$ 109,633
Interest and Fee Income, Loans Held-for-sale, Mortgages	410	384	878	923
Taxable interest on securities	6,318	5,383	20,550	15,859
Nontaxable interest on securities	1	9	18	52
Dividends on Federal Home Loan Bank stock	747	634	2,162	1,700
Other interest income	493	261	1,232	723
Total interest and dividend income	49,527	45,164	150,280	128,890
Interest expense:
Deposits	9,792	6,546	27,957	16,222
Federal Home Loan Bank advances	6,512	4,937	20,153	13,627
Junior subordinated debentures	245	232	750	629
Total interest expense	16,549	11,715	48,860	30,478
Net interest income	32,978	33,449	101,420	98,412
Provision for loan losses	400	350	1,575	750
Net interest income after provision for loan losses	32,578	33,099	99,845	97,662
Noninterest income:
Wealth management revenues	9,153	9,454	27,954	29,329
Mortgage banking revenues	4,840	2,624	11,126	8,403
Card interchange fees	1,099	983	3,114	2,791
Service charges on deposit accounts	939	885	2,743	2,651
Loan related derivative income	1,407	278	2,877	1,087
Income from bank-owned life insurance	569	572	1,784	1,624
Net realized losses on securities	0	0	(80)	0
Other income	335	419	944	1,066
Total noninterest income	18,342	15,215	50,462	46,951
Noninterest expense:
Salaries and employee benefits	18,332	17,283	54,387	52,359
Outsourced services	2,722	1,951	7,846	6,174
Net occupancy	1,933	2,013	5,835	5,945
Equipment	1,046	1,080	3,085	3,329
Legal, audit and professional fees	645	559	1,843	1,840
FDIC deposit insurance costs	(460)	410	509	1,236
Advertising and promotion	368	440	1,132	946
Amortization of intangibles	236	245	714	740
Other expenses	2,048	2,081	6,634	6,911
Total noninterest expense	26,870	26,062	81,985	79,480
Income before income taxes	24,050	22,252	68,322	65,133
Income tax expense	5,236	4,741	14,740	13,737
Net income	18,814	17,511	53,582	51,396
Net income applicable to common shareholders	$ 18,778	$ 17,475	$ 53,477	$ 51,284
Weighted average common shares outstanding - basic	17,338	17,283	17,324	17,263
Weighted average common shares outstanding - diluted	17,414	17,382	17,406	17,392
Per share information:
Basic earnings per common share	$ 1.08	$ 1.01	$ 3.09	$ 2.97
Diluted earnings per common share	1.08	1.01	3.07	2.95
Cash dividends declared per share	$ 0.51	$ 0.43	$ 1.49	$ 1.29

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 18,814	$ 17,511	$ 53,582	$ 51,396
Other comprehensive income (loss), net of tax:
Net change in fair value of available for sale debt securities	2,886	(4,531)	19,940	(18,057)
Net change in fair value of cash flow hedges	(171)	155	(1,235)	1,409
Net change in defined benefit plan obligations	227	361	680	1,081
Total other comprehensive income (loss), net of tax	2,942	(4,015)	19,385	(15,567)
Total comprehensive income	$ 21,756	$ 13,496	$ 72,967	$ 35,829

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) - 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, 2017		17,227,000
Shareholders' Equity, Beginning Balance at Dec. 31, 2017	$ 413,284	$ 1,077	$ 117,961	$ 317,756	$ (23,510)
Net income	51,396			51,396
Total other comprehensive income (loss), net of tax	(15,567)				(15,567)
Cash dividends declared	(22,467)			(22,467)
Share-based compensation	1,977		1,977
Exercise of stock options and issuance of other compensation-related equity awards, shares		63,000
Exercise of stock options and issuance of other compensation-related equity awards, value	(714)	$ 4	(718)
Common Stock, Shares Outstanding, Ending Balance at Sep. 30, 2018		17,290,000
Shareholders' Equity, Ending Balance at Sep. 30, 2018	427,909	$ 1,081	119,220	346,685	(39,077)
Common Stock, Shares Outstanding, Beginning Balance at Jun. 30, 2018		17,278,000
Shareholders' Equity, Beginning Balance at Jun. 30, 2018	421,571	$ 1,080	118,883	336,670	(35,062)
Net income	17,511			17,511
Total other comprehensive income (loss), net of tax	(4,015)				(4,015)
Cash dividends declared	(7,496)			(7,496)
Share-based compensation	658		658
Exercise of stock options and issuance of other compensation-related equity awards, shares		12,000
Exercise of stock options and issuance of other compensation-related equity awards, value	(320)	$ 1	(321)
Common Stock, Shares Outstanding, Ending Balance at Sep. 30, 2018		17,290,000
Shareholders' Equity, Ending Balance at Sep. 30, 2018	$ 427,909	$ 1,081	119,220	346,685	(39,077)
Common Stock, Shares Outstanding, Beginning Balance at Dec. 31, 2018	17,302,037	17,302,000
Shareholders' Equity, Beginning Balance at Dec. 31, 2018	$ 448,184	$ 1,081	119,888	355,524	(28,309)
Net income	53,582			53,582
Total other comprehensive income (loss), net of tax	19,385				19,385
Cash dividends declared	(26,063)			(26,063)
Share-based compensation	2,295		2,295
Exercise of stock options and issuance of other compensation-related equity awards, shares		36,000
Exercise of stock options and issuance of other compensation-related equity awards, value	$ (280)	$ 3	(283)
Common Stock, Shares Outstanding, Ending Balance at Sep. 30, 2019	17,338,348	17,338,000
Shareholders' Equity, Ending Balance at Sep. 30, 2019	$ 497,825	$ 1,084	121,900	383,765	(8,924)
Common Stock, Shares Outstanding, Beginning Balance at Jun. 30, 2019		17,336,000
Shareholders' Equity, Beginning Balance at Jun. 30, 2019	484,205	$ 1,083	121,115	373,873	(11,866)
Net income	18,814			18,814
Total other comprehensive income (loss), net of tax	2,942				2,942
Cash dividends declared	(8,922)			(8,922)
Share-based compensation	792		792
Exercise of stock options and issuance of other compensation-related equity awards, shares		2,000
Exercise of stock options and issuance of other compensation-related equity awards, value	$ (6)	$ 1	(7)
Common Stock, Shares Outstanding, Ending Balance at Sep. 30, 2019	17,338,348	17,338,000
Shareholders' Equity, Ending Balance at Sep. 30, 2019	$ 497,825	$ 1,084	$ 121,900	$ 383,765	$ (8,924)

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Unaudited) (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per share	$ 0.51	$ 0.43	$ 1.49	$ 1.29

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 53,582	$ 51,396
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	1,575	750
Depreciation of premises and equipment	2,478	2,454
Net amortization of premium and discount on securities and loans	3,113	2,157
Amortization of intangibles	714	740
Share-based compensation	2,295	1,977
Tax benefit from stock option exercises and other equity awards	202	454
Income from bank-owned life insurance	(1,784)	(1,624)
Net gains on loan sales and commissions on loans originated for others, including fair value adjustments	(10,749)	(7,950)
Net realized losses on securities	80	0
Proceeds from sales of loans	365,057	306,095
Loans originated for sale	(380,635)	(296,367)
(Increase) decrease in operating lease right-of-use assets	1,422	0
Increase (decrease) in operating lease liabilities	(1,312)	0
(Increase) decrease in other assets	(41,239)	(20,903)
Increase (decrease) in other liabilities	42,575	19,256
Net cash provided by (used in) operating activities	37,374	58,435
Cash flows from investing activities:
Purchases of mortgage-backed securities available for sale	(72,262)	(96,867)
Purchases of other investment securities available for sale	(10,507)	(30,964)
Proceeds from sale of other investment securities available for sale	9,920	0
Maturities and principal payments of mortgage-backed securities available for sale	96,521	63,918
Maturities and principal payments of other investment securities available for sale	51,135	6,795
Maturities and principal payments of mortgage-backed securities held to maturity	0	1,603
Remittance (purchases) of Federal Home Loan Bank stock	1,038	(4,008)
Net (increase) decrease in loans	(92,135)	(181,853)
Purchases of loans	(7,324)	(1,750)
Proceeds from the sale of property acquired through foreclosure or repossession	0	49
Purchases of premises and equipment	(2,768)	(2,320)
Purchases of bank-owned life insurance	0	(5,000)
Proceeds from surrender of bank-owned life insurance	326	0
Equity investment in real estate limited partnership	(1,256)	0
Net cash provided by (used in) investing activities	(27,312)	(250,397)
Cash flows from financing activities:
Net increase (decrease) in deposits	62,105	171,641
Proceeds from Federal Home Loan Bank advances	1,334,000	1,462,500
Repayment of Federal Home Loan Bank advances	(1,327,936)	(1,425,464)
Payment of contingent consideration liability	0	(1,217)
Net proceeds from stock option exercises and issuance of other equity awards	(280)	(714)
Cash dividends paid	(25,322)	(21,856)
Net cash provided by (used in) financing activities	42,567	184,890
Net increase (decrease) in cash and cash equivalents	52,629	(7,072)
Cash and cash equivalents at beginning of period	93,475	82,923
Cash and cash equivalents at end of period	146,104	75,851
Noncash Investing and Financing Activities:
Loans charged off	1,888	889
Loans transferred to property acquired through foreclosure or repossession	2,000	3,074
Operating lease right-of-use assets	28,923	0
Operating lease liabilities	30,853	0
Fair value of debt securities transferred from held-to-maturity to available for sale	10,316	0
Supplemental Disclosures:
Interest Payments	47,168	28,596
Income tax payments	$ 14,531	$ 12,585

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General Information	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; its automated teller machines (“ATMs”); telephone banking; mobile banking and its internet website (www.washtrust.com). The Unaudited 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. Certain previously reported amounts have been reclassified to conform to current year’s presentation. 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 Unaudited Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is included in the Unaudited 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. The Unaudited Consolidated Financial Statements of the Corporation presented herein have been prepared pursuant to the rules of the Securities and Exchange Commission (“SEC”) for quarterly reports on Form 10-Q and do not include all of the information and note disclosures required by GAAP. In the opinion of management, all adjustments (consisting of normal recurring adjustments) and disclosures considered necessary for the fair presentation of the accompanying Unaudited Consolidated Financial Statements have been included. Interim results are not necessarily indicative of the results of the entire year. The accompanying Unaudited Consolidated Financial Statements should be read in conjunction with the Audited Consolidated Financial Statements and notes thereto included in the Annual Report on Form 10-K for the fiscal year ended December 31, 2018 .

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	9 Months Ended
	Sep. 30, 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. Management assembled a project team to address the changes pursuant to Topic 842. The project team identified and reviewed all lease agreements in scope of Topic 842. 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. 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 on the Corporation’s consolidated financial statements associated with our 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 all expected 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 on January 1, 2020 and continues to evaluate the effect that this ASU will have on the consolidated financial statements and disclosures. 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” (“ASU 2019-04”) was issued to provide additional clarification on the scope and disclosure requirements of Topic 326. ASU 2019-04 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 May 2019, Accounting Standards Update No. 2019-05, “Financial Instruments - Credit Losses (Topic 326); Targeted Transition Relief” (“ASU 2019-05”) was issued to allow an entity to make an irrevocable fair value option election on instruments within the scope of Topic 326 that are measured at amortized cost, except for held to maturity debt securities. This election can be applied on an instrument-by-instrument basis upon the adoption of Topic 326. The effective dates of ASU 2019-04 and ASU 2019-05 are the same as the effective date of ASU 2016-13. To prepare for the adoption of ASU 2016-13 and related updates, the Corporation assembled a cross-functional project team that meets regularly to address the additional data requirements necessary, to determine the approach for implementation and to identify new internal controls over enhanced accounting processes that will be put into place for estimating the ACL. This has included assessing the adequacy of existing loan and loss data, as well as validating models for default and loss estimates. The Corporation has substantially completed the development of its Topic 326 compliant methodology. The new methodology will include models that contain additional assumptions used 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. 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. Based on the credit quality of our existing available for sale debt securities portfolio, the Corporation does not expect the adoption of ASU 2016-13, as it relates to debt securities, to be significant. The project team continues to review the output from “trial” runs and is in the process of assessing qualitative factors. The Corporation is also updating its accounting processes and policies and internal controls associated with the Topic 326 compliant methodology. The Corporation plans to finalize its Topic 326 compliant methodology, accounting policies and internal controls in the fourth quarter of 2019. Upon adoption, an increase to the ACL will be recorded with a corresponding one-time cumulative-effect adjustment to retained earnings. The FDIC approved a final rule that provides banking organizations the option to phase in over a three-year period the day-one adverse effects on regulatory capital that may result from the adoption of the new accounting standard. The Corporation is planning on adopting the capital transition relief over the permissible three-year period. 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 adoption of ASU 2018-13 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 adoption of ASU 2018-15 is not expected to have a material impact on the Corporation’s consolidated financial statements.

Cash and Due from Banks

Cash and Due from Banks	9 Months Ended
	Sep. 30, 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 Federal Reserve System (the “FRB”). Some or all of these reserve requirements may be satisfied with vault cash. Reserve balances am ounted to $27.6 million at September 30, 2019 and $21.6 million at December 31, 2018 and were included in cash and due from banks in the Unaudited Consolidated Balance Sheets. As of September 30, 2019 and December 31, 2018 , cash and due from banks included interest-bearing deposits in other banks of $81.9 million and $33.7 million , respectively.

Securities

Securities	9 Months Ended
	Sep. 30, 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) September 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $196,734 $927 ($337 ) $197,324 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 659,096 8,614 (2,805 ) 664,905 Individual name issuer trust preferred debt securities 13,320 — (899 ) 12,421 Corporate bonds 13,715 32 (1,377 ) 12,370 Total available for sale debt securities $882,865 $9,573 ($5,418 ) $887,020 Total securities $882,865 $9,573 ($5,418 ) $887,020 (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. As of September 30, 2019 and December 31, 2018 , debt securities with a fair value of $435.3 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 7 for additional disclosure on 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) Available for Sale September 30, 2019 Amortized Cost Fair Value Due in one year or less $105,671 $106,401 Due after one year to five years 340,179 342,582 Due after five years to ten years 289,520 290,083 Due after ten years 147,495 147,954 Total debt securities $882,865 $887,020 Included in the above table are debt securities with an amortized cost balance of $222.5 million and a fair value of $220.8 million at September 30, 2019 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 3 months to 17 years, with call features ranging from 1 month to 3 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 September 30, 2019 # Fair Unrealized # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises 3 $20,331 ($169 ) 4 $50,832 ($168 ) 7 $71,163 ($337 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 2 692 (1 ) 25 239,550 (2,804 ) 27 240,242 (2,805 ) Individual name issuer trust preferred debt securities — — — 5 12,421 (899 ) 5 12,421 (899 ) Corporate bonds — — — 3 10,425 (1,377 ) 3 10,425 (1,377 ) Total temporarily impaired securities 5 $21,023 ($170 ) 37 $313,228 ($5,248 ) 42 $334,251 ($5,418 ) (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 September 30, 2019 . Individual Name Issuer Trust Preferred Debt Securities Included in debt securities in an unrealized loss position at September 30, 2019 were five trust preferred securities issued by four individual companies in the banking sector. Management believes the unrealized losses on these debt security 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 September 30, 2019 , individual name issuer trust preferred debt securities with an amortized cost of $6.1 million and unrealized losses of $458 thousand were rated below investment grade by Standard & Poors, Inc. (“S&P”). Management reviewed the collectibility 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 September 30, 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 September 30, 2019 . Corporate Bonds At September 30, 2019 , the Corporation had three corporate bond holdings with unrealized losses totaling $1.4 million . These investment grade corporate bonds were issued by large corporations, primarily in the financial services industry. Management believes the unrealized losses on these bonds 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. 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 September 30, 2019 . The following table summarizes amounts relating to sales of securities: (Dollars in thousands) Three Months Nine Months For the periods ended September 30, 2019 2018 2019 2018 Proceeds from sales $— $— $9,920 $— Gross realized gains $— $— $— $— Gross realized losses — — (80 ) — Net realized losses on securities $— $— ($80 ) $—

Loans

Loans	9 Months Ended
	Sep. 30, 2019
Receivables [Abstract]
Loans	Loans The following is a summary of loans: (Dollars in thousands) September 30, December 31, 2018 Commercial: Commercial real estate (1) $1,517,320 $1,392,408 Commercial & industrial (2) 566,426 620,704 Total commercial 2,083,746 2,013,112 Residential Real Estate: Residential real estate (3) 1,378,518 1,360,387 Consumer: Home equity 294,250 280,626 Other (4) 21,592 26,235 Total consumer 315,842 306,861 Total loans (5) $3,778,106 $3,680,360 (1) 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) Consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (3) Consists of mortgage and homeowner construction loans secured by one- to four-family residential properties. (4) Consists of loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 . As of both September 30, 2019 and December 31, 2018 , loans amounting to $2.0 billion were pledged as collateral to the FHLB under a blanket pledge agreement and to the FRB for the discount window. See Note 7 for additional disclosure regarding borrowings. Past Due Loans Past due status is based on the contractual payment terms of the loan. The following tables present an age analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due September 30, 2019 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $— $— $684 $684 $1,516,636 $1,517,320 Commercial & industrial 1 — — 1 566,425 566,426 Total commercial 1 — 684 685 2,083,061 2,083,746 Residential Real Estate: Residential real estate 4,333 2,506 4,760 11,599 1,366,919 1,378,518 Consumer: Home equity 744 417 812 1,973 292,277 294,250 Other 11 — 88 99 21,493 21,592 Total consumer 755 417 900 2,072 313,770 315,842 Total loans $5,089 $2,923 $6,344 $14,356 $3,763,750 $3,778,106 (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 September 30, 2019 and December 31, 2018 , were nonaccrual loans of $9.8 million and $8.6 million , respectively. All loans 90 days or more past due at September 30, 2019 and December 31, 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 Sep 30, Dec 31, Sep 30, Dec 31, Sep 30, Dec 31, No Related Allowance Recorded Commercial: Commercial real estate $684 $925 $926 $926 $— $— Commercial & industrial — 4,681 — 4,732 — — Total commercial 684 5,606 926 5,658 — — Residential Real Estate: Residential real estate 12,531 9,347 13,368 9,695 — — Consumer: Home equity 1,379 1,360 1,379 1,360 — — Other 88 — 88 — — — Total consumer 1,467 1,360 1,467 1,360 — — Subtotal 14,682 16,313 15,761 16,713 — — With Related Allowance Recorded Commercial: Commercial real estate $— $— $— $— $— $— Commercial & industrial — 52 — 73 — — Total commercial — 52 — 73 — — Residential Real Estate: Residential real estate 360 364 386 390 96 100 Consumer: Home equity 220 85 220 85 220 24 Other 19 22 19 22 5 3 Total consumer 239 107 239 107 225 27 Subtotal 599 523 625 570 321 127 Total impaired loans $15,281 $16,836 $16,386 $17,283 $321 $127 Total: Commercial $684 $5,658 $926 $5,731 $— $— Residential real estate 12,891 9,711 13,754 10,085 96 100 Consumer 1,706 1,467 1,706 1,467 225 27 Total impaired loans $15,281 $16,836 $16,386 $17,283 $321 $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 tables present 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 Three months ended September 30, 2019 2018 2019 2018 Commercial: Commercial real estate $886 $— $— $— Commercial & industrial — 5,324 — 62 Total commercial 886 5,324 — 62 Residential Real Estate: Residential real estate 12,017 9,265 109 96 Consumer: Home equity 1,414 1,424 16 22 Other 108 25 3 — Total consumer 1,522 1,449 19 22 Totals $14,425 $16,038 $128 $180 (Dollars in thousands) Average Recorded Investment Interest Income Recognized Nine months ended September 30, 2019 2018 2019 2018 Commercial: Commercial real estate $929 $1,352 $1 $— Commercial & industrial 2,835 5,599 103 201 Total commercial 3,764 6,951 104 201 Residential Real Estate: Residential real estate 10,972 9,709 331 293 Consumer: Home equity 1,409 1,045 43 41 Other 55 85 2 5 Total consumer 1,464 1,130 45 46 Totals $16,200 $17,790 $480 $540 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. The following is a summary of nonaccrual loans, segregated by class of loans: (Dollars in thousands) Sep 30, Dec 31, Commercial: Commercial real estate $684 $925 Commercial & industrial — — Total commercial 684 925 Residential Real Estate: Residential real estate 12,531 9,346 Consumer: Home equity 1,599 1,436 Other 88 — Total consumer 1,687 1,436 Total nonaccrual loans $14,902 $11,707 Accruing loans 90 days or more past due $— $— As of September 30, 2019 and December 31, 2018 , loans secured by one- to four-family residential property amounting to $5.9 million and $761 thousand , respectively, were in process of foreclosure. Nonaccrual loans of $5.1 million and $3.1 million , respectively, were current as to the payment of principal and interest at September 30, 2019 and December 31, 2018 . There were no significant commitments to lend additional funds to borrowers whose loans were on nonaccrual status at September 30, 2019 . Troubled Debt Restructurings 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. 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 $876 thousand and $5.6 million , respectively, at September 30, 2019 and December 31, 2018 . The allowance for loan losses included specific reserves for these troubled debt restructurings of $101 thousand and $103 thousand , respectively, at September 30, 2019 and December 31, 2018 . For the three and nine months ended September 30, 2019 , there were no loans modified as a troubled debt restructuring. For the three months ended September 30, 2018 , there were no loans modified as a troubled debt restructuring. For the nine months ended September 30, 2018 , there was one 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. For the three and nine months ended September 30, 2019 there were no payment defaults on troubled debt restructured loans modified within the previous 12 months. For the three and nine months ended September 30, 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 September 30, 2019 , there were no significant commitments to lend additional funds to borrowers whose loans had been 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 Sep 30, Dec 31, Sep 30, Dec 31, Sep 30, Dec 31, Commercial: Commercial real estate $1,498,212 $1,387,666 $18,224 $205 $884 $4,537 Commercial & industrial 529,219 559,019 25,679 50,426 11,528 11,259 Total commercial $2,027,431 $1,946,685 $43,903 $50,631 $12,412 $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 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 loan type and credit quality indicator: (Dollars in thousands) Current Past Due Sep 30, Dec 31, Sep 30, Dec 31, Residential Real Estate: Self-originated mortgages $1,261,364 $1,238,402 $10,503 $9,079 Purchased mortgages 105,555 111,465 1,096 1,441 Total residential real estate $1,366,919 $1,349,867 $11,599 $10,520 Consumer: Home equity $292,277 $278,637 $1,973 $1,989 Other 21,493 26,202 99 33 Total consumer $313,770 $304,839 $2,072 $2,022

Allowance for Loan Losses

Allowance for Loan Losses	9 Months Ended
	Sep. 30, 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 three months ended September 30, 2019 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $16,882 $4,453 $21,335 $4,857 $913 $293 $1,206 $27,398 Charge-offs (947 ) (1 ) (948 ) — — (18 ) (18 ) (966 ) Recoveries — 123 123 — 36 6 42 165 Provision 866 (1,128 ) (262 ) 554 64 44 108 400 Ending Balance $16,801 $3,447 $20,248 $5,411 $1,013 $325 $1,338 $26,997 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the nine months ended September 30, 2019 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) 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 (947 ) (19 ) (966 ) (486 ) (372 ) (64 ) (436 ) (1,888 ) Recoveries — 151 151 — 71 16 87 238 Provision 2,367 (2,532 ) (165 ) 1,910 (289 ) 119 (170 ) 1,575 Ending Balance $16,801 $3,447 $20,248 $5,411 $1,013 $325 $1,338 $26,997 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the three months ended September 30, 2018 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $12,443 $6,642 $19,085 $5,314 $1,375 $400 $1,775 $26,174 Charge-offs — (1 ) (1 ) (68 ) — (27 ) (27 ) (96 ) Recoveries — 71 71 — 2 8 10 81 Provision 1,052 535 1,587 (1,131 ) 12 (118 ) (106 ) 350 Ending Balance $13,495 $7,247 $20,742 $4,115 $1,389 $263 $1,652 $26,509 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the nine months ended September 30, 2018 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) 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 ) (8 ) (635 ) (73 ) (111 ) (70 ) (181 ) (889 ) Recoveries 25 104 129 — 12 19 31 160 Provision 1,368 1,571 2,939 (1,239 ) (924 ) (26 ) (950 ) 750 Ending Balance $13,495 $7,247 $20,742 $4,115 $1,389 $263 $1,652 $26,509 (1) Commercial real estate loans. (2) Commercial & industrial loans. 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) September 30, 2019 December 31, 2018 Loans Related Allowance Loans Related Allowance Loans Individually Evaluated for Impairment Commercial: Commercial real estate $684 $— $925 $— Commercial & industrial — — 4,714 — Total commercial 684 — 5,639 — Residential Real Estate: Residential real estate 12,890 96 9,710 100 Consumer: Home equity 1,599 220 1,445 24 Other 107 5 22 3 Total consumer 1,706 225 1,467 27 Subtotal 15,280 321 16,816 127 Loans Collectively Evaluated for Impairment Commercial: Commercial real estate 1,516,636 16,801 1,391,483 15,381 Commercial & industrial 566,426 3,447 615,990 5,847 Total commercial 2,083,062 20,248 2,007,473 21,228 Residential Real Estate: Residential real estate 1,365,628 5,315 1,350,677 3,887 Consumer: Home equity 292,651 793 279,182 1,579 Other 21,485 320 26,212 251 Total consumer 314,136 1,113 305,394 1,830 Subtotal 3,762,826 26,676 3,663,544 26,945 Total $3,778,106 $26,997 $3,680,360 $27,072

Federal Home Loan Bank Advances

Federal Home Loan Bank Advances	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Borrowings	Federal Home Loan Bank Advances Advances payable to the FHLB amounted to $956.8 million and $950.7 million , respectively, at September 30, 2019 and December 31, 2018 . As of September 30, 2019 and December 31, 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 $601.5 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 September 30, 2019 : (Dollars in thousands) Scheduled Weighted Average Rate October 1, 2019 to December 31, 2019 $355,822 2.56 % 2020 444,533 2.34 2021 86,222 2.73 2022 55,447 3.65 2023 9,428 4.01 2024 and thereafter 5,334 5.06 Balance at September 30, 2019 $956,786 2.56 % In October 2019, FHLB advances totaling $78.8 million were modified to lower interest rates and the maturities of these advances were extended. Original maturity dates ranging from 2021 to 2023 were modified to 2024 to 2026. The original weighted average interest rate was 3.52% and was revised to 2.76%

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 30, 2019
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Regulatory Capital Requirements	Shareholders' Equity Regulatory Capital Requirements Capital levels at September 30, 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 Provisions Amount Ratio Amount Ratio Amount Ratio September 30, 2019 Total Capital (to Risk-Weighted Assets): Corporation $486,454 12.94 % $300,835 8.00 % N/A N/A Bank 483,783 12.87 300,790 8.00 $375,988 10.00 % Tier 1 Capital (to Risk-Weighted Assets): Corporation 459,140 12.21 225,627 6.00 N/A N/A Bank 456,469 12.14 225,593 6.00 300,790 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 437,142 11.62 169,220 4.50 N/A N/A Bank 456,469 12.14 169,195 4.50 244,392 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 459,140 8.97 204,810 4.00 N/A N/A Bank 456,469 8.92 204,722 4.00 255,903 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 included 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 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 September 30, 2019 and December 31, 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 FRB’s capital adequacy guidelines.

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
	Sep. 30, 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 September 30, 2019 and December 31, 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 September 30, 2019 and December 31, 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 September 30, 2019 and December 31, 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 September 30, 2019 and December 31, 2018 , Washington Trust had interest rate swap contracts with commercial loan borrowers with notional amounts of $729.9 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 September 30, 2019 , the notional amounts of risk participation-out agreements and risk participation-in agreements were $44.5 million and $73.0 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. The Corporation uses these foreign exchange contracts on a limited basis to reduce its exposure to fluctuations in currency exchange rates associated with a commercial loan that is denominated in a foreign currency. These derivatives 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. As of September 30, 2019 and December 31, 2018 , the notional amount of foreign exchange contracts was $2.6 million and $2.8 million , respectively. 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 September 30, 2019 , the notional amounts of interest rate lock commitments and forward sale commitments were $84.8 million and $156.6 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 Unaudited Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet Location Sep 30, 2019 Dec 31, 2018 Balance Sheet Location Sep 30, 2019 Dec 31, 2018 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 2 903 Other liabilities 1,000 — Interest rate floors Other assets 69 37 Other liabilities — — Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Other assets 37,765 5,340 Other liabilities 80 7,719 Mirror swaps with counterparties Other assets 80 7,592 Other liabilities 37,913 5,392 Risk participation agreements Other assets 1 — Other liabilities 3 — Foreign exchange contracts Other assets 6 — Other liabilities — 7 Forward loan commitments: Interest rate lock commitments Other assets 1,762 806 Other liabilities 1 — Forward sale commitments Other assets 393 — Other liabilities 977 816 Gross amounts 40,078 14,698 39,974 13,934 Less amounts offset in Consolidated Balance Sheets (1) 157 10,732 157 10,732 Net amounts presented in Consolidated Balance Sheets 39,921 3,966 39,817 3,202 Less collateral pledged (2) — — 37,695 1,460 Net amounts $39,921 $3,966 $2,122 $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 Unaudited Consolidated Statements of Changes in Shareholders’ Equity and Unaudited Consolidated Statements of Income: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps $18 $17 $32 $66 Interest rate swaps (211 ) 189 (1,442 ) 1,322 Interest rate floors 22 (51 ) 175 21 Total ($171 ) $155 ($1,235 ) $1,409 For derivatives designated as cash flow hedging instruments, see Note 15 for additional disclosure pertaining to the amounts and location of reclassifications from accumulated other comprehensive income into earnings. (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Nine Months Periods ended September 30, Statement of Income Location 2019 2018 2019 2018 Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income $12,284 ($3,178 ) 39,568 (15,374 ) Mirror swaps with counterparties Loan related derivative income (11,108 ) 3,415 (36,958 ) 16,384 Risk participation agreements Loan related derivative income 213 25 213 25 Foreign exchange contracts Loan related derivative income 18 16 54 52 Forward loan commitments: Interest rate lock commitments Mortgage banking revenues (340 ) (504 ) $955 ($327 ) Forward sale commitments Mortgage banking revenues (101 ) 316 (1,969 ) 1,552 Total $966 $90 $1,863 $2,312

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 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) September 30, December 31, Aggregate fair value $44,657 $20,996 Aggregate principal balance 43,696 20,498 Difference between fair value and principal balance $961 $498 Changes in fair value of mortgage loans held for sale accounted for under the fair value option election amounted to a decrease of $82 thousand and an increase of $462 thousand in the three and nine months ended September 30, 2019 , respectively, compared to decreases of $352 thousand and $240 thousand in the three and nine months ended September 30, 2018 , respectively. 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 Unaudited Consolidated Statements of Income. There were no mortgage loans held for sale 90 days or more past due as of September 30, 2019 and December 31, 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 debt securities held at September 30, 2019 and December 31, 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 debt securities held at September 30, 2019 and December 31, 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 Unaudited 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 September 30, 2019 and December 31, 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. 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. One of the two earn-out periods associated with this contingent consideration liability ended December 31, 2017 and a payment of $1.2 million was made by the Corporation in the first quarter of 2018. The likelihood of payout on the remaining earn-out period had been deemed remote and as a result the fair value of the contingent consideration liability was reduced to zero in the fourth quarter of 2018 . There have been no changes to the fair value of the contingent consideration liability for the three and nine months ended September 30, 2019 . 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 (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2019 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $197,324 $— $197,324 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 664,905 — 664,905 — Individual name issuer trust preferred debt securities 12,421 — 12,421 — Corporate bonds 12,370 — 12,370 — Mortgage loans held for sale 44,657 — 44,657 — Derivative assets 39,921 — 39,921 — Total assets at fair value on a recurring basis $971,598 $— $971,598 $— Liabilities: Derivative liabilities $39,817 $— $39,817 $— Total liabilities at fair value on a recurring basis $39,817 $— $39,817 $— (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs 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 nine months ended September 30, 2019 and 2018 . Items Recorded at Fair Value on a Nonrecurring Basis The following table presents the carrying value of assets held at September 30, 2019 , which were written down to fair value during the nine months ended September 30, 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 $1,451 $— $— $1,451 Property acquired through foreclosure or repossession 2,000 — — 2,000 Total assets at fair value on a nonrecurring basis $3,451 $— $— $3,451 The allowance for loan losses on collateral dependent impaired loans amounted to $221 thousand at September 30, 2019 . 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 . 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) September 30, 2019 Collateral dependent impaired loans $1,451 Appraisals of collateral Discount for costs to sell 0% - 18% (13%) Appraisal adjustments (1) 0% - 100% (19%) Property acquired through foreclosure or repossession $2,000 Appraisals of collateral Discount for costs to sell 20% Appraisal adjustments (1) 13% (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) September 30, 2019 Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: Loans, net of allowance for loan losses $3,751,109 $3,749,391 $— $— $3,749,391 Financial Liabilities: Time deposits $1,223,662 $1,239,646 $— $1,239,646 $— FHLB advances 956,786 962,160 — 962,160 — Junior subordinated debentures 22,681 19,265 — 19,265 — (Dollars in thousands) December 31, 2018 Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs 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	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue from Contracts with Customers	Revenue from Contracts with Customers The following tables summarize total revenues as presented in the Unaudited Consolidated Statements of Income and the related amounts which are from contracts with customers within the scope of Topic 606. As shown below, a substantial portion of our revenues are specifically excluded from the scope of Topic 606. For the three months ended September 30, 2019 2018 (Dollars in thousands) As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 Net interest income $32,978 $— $33,449 $— Noninterest income: Asset-based wealth management revenues 9,013 9,013 9,322 9,322 Transaction-based wealth management revenues 140 140 132 132 Total wealth management revenues 9,153 9,153 9,454 9,454 Mortgage banking revenues 4,840 — 2,624 — Card interchange fees 1,099 1,099 983 983 Service charges on deposit accounts 939 939 885 885 Loan related derivative income 1,407 — 278 — Income from bank-owned life insurance 569 — 572 — Net realized losses on securities — — — — Other income 335 323 419 419 Total noninterest income 18,342 11,514 15,215 11,741 Total revenues $51,320 $11,514 $48,664 $11,741 For the nine months ended September 30, 2019 2018 (Dollars in thousands) As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 Net interest income $101,420 $— $98,412 $— Noninterest income: Asset-based wealth management revenues 27,075 27,075 28,413 28,413 Transaction-based wealth management revenues 879 879 916 916 Total wealth management revenues 27,954 27,954 29,329 29,329 Mortgage banking revenues 11,126 — 8,403 — Card interchange fees 3,114 3,114 2,791 2,791 Service charges on deposit accounts 2,743 2,743 2,651 2,651 Loan related derivative income 2,877 — 1,087 — Income from bank-owned life insurance 1,784 — 1,624 — Net realized losses on securities (80 ) — — — Other income 944 917 1,066 1,051 Total noninterest income 50,462 34,728 46,951 35,822 Total revenues $151,882 $34,728 $145,363 $35,822 The following table presents revenue from contracts with customers based on the timing of revenue recognition: (Dollars in thousands) Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Revenue recognized at a point in time: Card interchange fees $1,099 $983 $3,114 $2,791 Service charges on deposit accounts 728 670 2,109 2,045 Other income 268 258 771 732 Revenue recognized over time: Wealth management revenues 9,153 9,454 27,954 29,329 Service charges on deposit accounts 211 215 634 606 Other income 55 161 146 319 Total revenues from contracts in scope of Topic 606 $11,514 $11,741 $34,728 $35,822 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 $4.8 million at both September 30, 2019 and December 31, 2018 and were included in other assets in the Unaudited Consolidated Balance Sheets. Deferred revenues, which are considered contract liabilities under Topic 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 September 30, 2019 and December 31, 2018 and were included in other liabilities in the Unaudited Consolidated Balance Sheets. For commissions and incentives that are in-scope of Topic 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 $683 thousand at September 30, 2019 , compared to $458 thousand at December 31, 2018 and were included in other assets in the Unaudited Consolidated Balance Sheets.

Defined Benefit Pension Plans

Defined Benefit Pension Plans	9 Months Ended
	Sep. 30, 2019
Defined Benefit Plan [Abstract]
Defined Benefit Pension Plans	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. 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 Three Months Nine Months Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net Periodic Benefit Cost: Service cost (1) $510 $561 $1,528 $1,683 $31 $27 $94 $81 Interest cost (2) 741 679 2,225 2,036 140 119 422 356 Expected return on plan assets (2) (1,124 ) (1,318 ) (3,371 ) (3,954 ) — — — — Amortization of prior service credit (2) (4 ) (6 ) (12 ) (17 ) — — — — Recognized net actuarial loss (2) 198 374 594 1,122 104 103 307 308 Net periodic benefit cost $321 $290 $964 $870 $275 $249 $823 $745 (1) Included in salaries and employee benefits expense in the Unaudited Consolidated Statements of Income. (2) Included in other expenses in the Unaudited Consolidated Statements of Income. The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost: Qualified Pension Plan Non-Qualified Retirement Plans For the nine months ended September 30, 2019 2018 2019 2018 Measurement date Dec 31, 2018 Dec 31, 2017 Dec 31, 2018 Dec 31, 2017 Equivalent single discount rate for benefit obligations 4.38% 3.69% 4.28% 3.58% Equivalent single discount rate for service cost 4.44 3.76 4.48 3.79 Equivalent single discount rate for interest cost 4.12 3.42 3.98 3.22 Expected long-term return on plan assets 5.75 6.75 N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75

Share-Based Compensation Arrang

Share-Based Compensation Arrangements	9 Months Ended
	Sep. 30, 2019
Share-based Payment Arrangement [Abstract]
Share-Based Compensation Arrangements	Share-Based Compensation Arrangements During the nine months ended September 30, 2019 , the Corporation granted performance share unit awards and nonvested share unit awards. Performance share awards were granted to certain executive and non-executive officers to provide them with the opportunity to earn shares of common stock of the Corporation. The performance share awards were valued at fair market value as determined by the closing price of the Corporation’s common stock on the award date. The weighted average fair value of the performance share awards was $52.83 . The number of shares to be vested will be contingent upon the Corporation’s attainment of certain performance measures as detailed in the performance share award agreements. The performance share awards will earned over a 3 -year performance period and the current performance assumption results in 43,360 shares being earned. The Corporation granted to non-executive officers and directors 10,870 nonvested share units, with 3 -year cliff vesting. The weighted average grant date fair value of the nonvested share units was $51.43 .

Business Segments

Business Segments	9 Months Ended
	Sep. 30, 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. 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 support unit expenses such as technology, operations and other support functions. 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 bank-owned life insurance (“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 table presents the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Commercial Banking Wealth Management Services Corporate Consolidated Total Three months ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net interest income (expense) $28,515 $27,036 ($114 ) ($90 ) $4,577 $6,503 $32,978 $33,449 Provision for loan losses 400 350 — — — — 400 350 Net interest income (expense) after provision for loan losses 28,115 26,686 (114 ) (90 ) 4,577 6,503 32,578 33,099 Noninterest income 8,607 5,174 9,153 9,454 582 587 18,342 15,215 Noninterest expenses: Depreciation and amortization expense 642 654 360 371 40 44 1,042 1,069 Other noninterest expenses 16,255 15,599 6,217 6,194 3,356 3,200 25,828 24,993 Total noninterest expenses 16,897 16,253 6,577 6,565 3,396 3,244 26,870 26,062 Income before income taxes 19,825 15,607 2,462 2,799 1,763 3,846 24,050 22,252 Income tax expense 4,347 3,344 646 710 243 687 5,236 4,741 Net income $15,478 $12,263 $1,816 $2,089 $1,520 $3,159 $18,814 $17,511 Total assets at period end $3,994,458 $3,694,991 $78,812 $69,494 $1,125,608 $1,006,187 $5,198,878 $4,770,672 Expenditures for long-lived assets 662 612 87 14 48 19 797 645 (Dollars in thousands) Commercial Banking Wealth Management Services Corporate Consolidated Total Nine months ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net interest income (expense) $83,684 $79,656 ($361 ) ($225 ) $18,097 $18,981 $101,420 $98,412 Provision for loan losses 1,575 750 — — — — 1,575 750 Net interest income (expense) after provision for loan losses 82,109 78,906 (361 ) (225 ) 18,097 18,981 99,845 97,662 Noninterest income 20,753 15,947 27,961 29,329 1,748 1,675 50,462 46,951 Noninterest expenses: Depreciation and amortization expense 1,985 1,928 1,089 1,137 118 129 3,192 3,194 Other noninterest expenses 48,676 46,574 19,631 19,986 10,486 9,726 78,793 76,286 Total noninterest expenses 50,661 48,502 20,720 21,123 10,604 9,855 81,985 79,480 Income before income taxes 52,201 46,351 6,880 7,981 9,241 10,801 68,322 65,133 Income tax expense 11,371 9,834 1,845 2,008 1,524 1,895 14,740 13,737 Net income $40,830 $36,517 $5,035 $5,973 $7,717 $8,906 $53,582 $51,396 Total assets at period end $3,994,458 $3,694,991 $78,812 $69,494 $1,125,608 $1,006,187 $5,198,878 $4,770,672 Expenditures for long-lived assets 2,259 1,864 379 327 130 129 2,768 2,320

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	9 Months Ended
	Sep. 30, 2019
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) The following tables present the activity in other comprehensive income (loss): Three months ended September 30, 2019 2018 (Dollars in thousands) Pre-tax Amounts Income Taxes Net of Tax Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $3,772 $886 $2,886 ($5,924 ) ($1,393 ) ($4,531 ) Net losses on debt securities reclassified into earnings (1) — — — — — — Net change in fair value of available for sale debt securities 3,772 886 2,886 (5,924 ) (1,393 ) (4,531 ) Cash flow hedges: Change in fair value of cash flow hedges (283 ) (66 ) (217 ) (626 ) (148 ) (478 ) Net cash flow hedge losses reclassified into earnings (2) 60 14 46 830 197 633 Net change in fair value of cash flow hedges (223 ) (52 ) (171 ) 204 49 155 Defined benefit plan obligations: Amortization of net actuarial losses (3) 300 70 230 477 112 365 Amortization of net prior service credits (3) (4 ) (1 ) (3 ) (6 ) (2 ) (4 ) Net change in defined benefit plan obligations 296 69 227 471 110 361 Total other comprehensive income (loss) $3,845 $903 $2,942 ($5,249 ) ($1,234 ) ($4,015 ) (1) The pre-tax amount is reported as net realized losses on securities in the Unaudited 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 Unaudited Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Unaudited Consolidated Statements of Income. Nine months ended September 30, 2019 2018 (Dollars in thousands) Pre-tax Amounts Income Taxes Net of Tax Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $25,985 $6,106 $19,879 ($23,605 ) ($5,548 ) ($18,057 ) Net losses on debt securities reclassified into earnings (1) 80 19 61 — — — Net change in fair value of available for sale debt securities 26,065 6,125 19,940 (23,605 ) (5,548 ) (18,057 ) Cash flow hedges: Change in fair value of cash flow hedges (1,653 ) (388 ) (1,265 ) 632 50 582 Net cash flow hedge losses reclassified into earnings (2) 39 9 30 1,082 255 827 Net change in fair value of cash flow hedges (1,614 ) (379 ) (1,235 ) 1,714 305 1,409 Defined benefit plan obligations: Amortization of net actuarial losses (3) 900 211 689 1,430 337 1,093 Amortization of net prior service credits (3) (12 ) (3 ) (9 ) (17 ) (5 ) (12 ) Net change in defined benefit plan obligations 888 208 680 1,413 332 1,081 Total other comprehensive (loss) income $25,339 $5,954 $19,385 ($20,478 ) ($4,911 ) ($15,567 ) (1) The pre-tax amount is reported as net realized losses on securities in the Unaudited 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 Unaudited Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Unaudited 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 (Losses) Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total For the three months ended September 30, 2019 Balance at July 1, 2019 $292 ($873 ) ($11,285 ) ($11,866 ) Other comprehensive income (loss) before reclassifications 2,886 (217 ) — 2,669 Amounts reclassified from accumulated other comprehensive income — 46 227 273 Net other comprehensive income (loss) 2,886 (171 ) 227 2,942 Balance at September 30, 2019 $3,178 ($1,044 ) ($11,058 ) ($8,924 ) (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 For the nine months ended September 30, 2019 Balance at January 1, 2019 ($16,762 ) $191 ($11,738 ) ($28,309 ) Other comprehensive income (loss) before reclassifications 19,879 (1,265 ) — 18,614 Amounts reclassified from accumulated other comprehensive income 61 30 680 771 Net other comprehensive income (loss) 19,940 (1,235 ) 680 19,385 Balance at September 30, 2019 $3,178 ($1,044 ) ($11,058 ) ($8,924 ) (Dollars in thousands) Net Unrealized Losses on Available For Sale Debt Securities Net Unrealized Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total For the three months ended September 30, 2018 Balance at July 1, 2018 ($21,060 ) $826 ($14,828 ) ($35,062 ) Other comprehensive loss before reclassifications (4,531 ) (478 ) — (5,009 ) Amounts reclassified from accumulated other comprehensive income — 633 361 994 Net other comprehensive (loss) income (4,531 ) 155 361 (4,015 ) Balance at September 30, 2018 ($25,591 ) $981 ($14,467 ) ($39,077 ) (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 For the nine months ended September 30, 2018 Balance at January 1, 2018 ($7,534 ) ($428 ) ($15,548 ) ($23,510 ) Other comprehensive (loss) income before reclassifications (18,057 ) 582 — (17,475 ) Amounts reclassified from accumulated other comprehensive income — 827 1,081 1,908 Net other comprehensive (loss) income (18,057 ) 1,409 1,081 (15,567 ) Balance at September 30, 2018 ($25,591 ) $981 ($14,467 ) ($39,077 )

Earnings Per Common Share

Earnings Per Common Share	9 Months Ended
	Sep. 30, 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) Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Earnings per common share - basic: Net income $18,814 $17,511 $53,582 $51,396 Less dividends and undistributed earnings allocated to participating securities (36 ) (36 ) (105 ) (112 ) Net income available to common shareholders $18,778 $17,475 $53,477 $51,284 Weighted average common shares 17,338 17,283 17,324 17,263 Earnings per common share - basic $1.08 $1.01 $3.09 $2.97 Earnings per common share - diluted: Net income $18,814 $17,511 $53,582 $51,396 Less dividends and undistributed earnings allocated to participating securities (36 ) (36 ) (105 ) (112 ) Net income available to common shareholders $18,778 $17,475 $53,477 $51,284 Weighted average common shares 17,338 17,283 17,324 17,263 Dilutive effect of common stock equivalents 76 99 82 129 Weighted average diluted common shares 17,414 17,382 17,406 17,392 Earnings per common share - diluted $1.08 $1.01 $3.07 $2.95 Weighted average common stock equivalents, not included in common stock equivalents above because they were anti-dilutive, totaled 93,075 and 87,775 , respectively for the three and nine months ended September 30, 2019 , compared to 41,525 and 46,692 , respectively, for the same periods in 2018 .

Leases

Leases	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
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. The Corporation adopted the provisions of ASU 2016-02 (Topic 842) on January 1, 2019. Operating lease right-of-use (“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. Upon adoption, operating lease ROU assets totaling $28.9 million and operating lease liabilities totaling $30.9 million were recognized in our Unaudited Consolidated Balance Sheets for leases that existed at the adoption date, based on the present value of lease payments over the remaining lease term. Operating leases entered into after the adoption date will be recognized as an operating lease ROU asset and operating lease liability at the commencement date of the new lease. The Corporation’s leases do not provide an implicit interest rate, therefore the Corporation used its incremental collateralized borrowing rates commensurate with the underlying lease terms to determine the present value of operating lease liabilities. The weighted average discount rate used to discount operating lease liabilities at September 30, 2019 was 3.66% . 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 Unaudited 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. As of September 30, 2019 , the Corporation has one lease that has not yet commenced. At September 30, 2019 , lease expiration dates ranged from 2 months to 21 years, with additional renewal options on certain leases ranging from 1 to 5 years. At September 30, 2019 , the weighted average remaining lease term for the Corporation’s operating leases was 14.1 years. Rental expense for operating leases is recognized on a straight-line basis over the lease term and amounted to $944 thousand and $2.8 million , respectively, for the three and nine months ended September 30, 2019 , compared to $942 thousand and $2.8 million , respectively, for the same periods in 2018 . Variable lease components, such as consumer price index adjustments, are expensed as incurred and not included in ROU assets and operating lease liabilities. The following table presents the undiscounted annual lease payments under the terms of the Corporation’s operating leases at September 30, 2019 , including a reconciliation to the present value of operating lease liabilities recognized in the Corporation’s Unaudited Consolidated Balance Sheets: (Dollars in thousands) October 1, 2019 to December 31, 2019 $930 2020 3,515 2021 3,312 2022 3,165 2023 3,090 2024 and thereafter 24,716 Total operating lease payments (1) 38,728 Less interest 9,187 Present value of operating lease liabilities (2) $29,541 (1) Includes $4.2 million related to options to extend lease terms that are reasonably certain of being exercised. (2) Includes short-term operating lease liabilities of $2.3 million . The following table presents the components of total lease expense and operating cash flows: (Dollars in thousands) Periods ended September 30, 2019 Three Months Nine Months Lease Expense: Operating lease expense $931 $2,787 Variable lease expense 13 36 Total lease expense (1) $944 $2,823 Cash Paid: Cash paid reducing operating lease liabilities $926 $2,677 (1) Included in net occupancy expenses in the Unaudited 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	9 Months Ended
	Sep. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Financial Instruments with Off-Balance Sheet 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 Unaudited 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) Sep 30, Dec 31, Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $481,350 $533,884 Home equity lines 290,442 270,462 Other loans 74,931 46,698 Standby letters of credit 9,343 7,706 Financial instruments whose notional amounts exceed the amount of credit risk: Forward loan commitments: Interest rate lock commitments 84,820 30,766 Forward sale commitments 156,594 61,993 Loan related derivative contracts: Interest rate swaps with customers 729,913 648,050 Mirror swaps with counterparties 729,913 648,050 Risk participation-in agreements 73,040 46,510 Foreign exchange contracts 2,648 2,784 Interest rate risk management contracts: Interest rate swaps 60,000 60,000 See Note 9 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 $9.3 million and $7.7 million , respectively, as of September 30, 2019 and December 31, 2018 . At September 30, 2019 and December 31, 2018 , there were no liabilities to beneficiaries resulting from standby letters of credit. Fee income on standby letters of credit was insignificant for the three and nine months ended September 30, 2019 and 2018 . Forward 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.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Consolidation	The Unaudited 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. Certain previously reported amounts have been reclassified to conform to current year’s presentation. 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 Unaudited Consolidated Balance Sheets. Interest expense on the junior subordinated debentures is included in the Unaudited Consolidated Statements of Income.
Basis of Accounting	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.
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.

Leases (Policies)

Leases (Policies)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
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. The Corporation adopted the provisions of ASU 2016-02 (Topic 842) on January 1, 2019. Operating lease right-of-use (“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. Upon adoption, operating lease ROU assets totaling $28.9 million and operating lease liabilities totaling $30.9 million were recognized in our Unaudited Consolidated Balance Sheets for leases that existed at the adoption date, based on the present value of lease payments over the remaining lease term. Operating leases entered into after the adoption date will be recognized as an operating lease ROU asset and operating lease liability at the commencement date of the new lease. The Corporation’s leases do not provide an implicit interest rate, therefore the Corporation used its incremental collateralized borrowing rates commensurate with the underlying lease terms to determine the present value of operating lease liabilities. The weighted average discount rate used to discount operating lease liabilities at September 30, 2019 was 3.66% . 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 Unaudited 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. As of September 30, 2019 , the Corporation has one lease that has not yet commenced. At September 30, 2019 , lease expiration dates ranged from 2 months to 21 years, with additional renewal options on certain leases ranging from 1 to 5 years. At September 30, 2019 , the weighted average remaining lease term for the Corporation’s operating leases was 14.1 years. Rental expense for operating leases is recognized on a straight-line basis over the lease term and amounted to $944 thousand and $2.8 million , respectively, for the three and nine months ended September 30, 2019 , compared to $942 thousand and $2.8 million , respectively, for the same periods in 2018 . Variable lease components, such as consumer price index adjustments, are expensed as incurred and not included in ROU assets and operating lease liabilities.

Securities (Tables)

Securities (Tables)	9 Months Ended
	Sep. 30, 2019
Investments, Debt and Equity Securities [Abstract]
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) September 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Available for Sale Debt Securities: Obligations of U.S. government-sponsored enterprises $196,734 $927 ($337 ) $197,324 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 659,096 8,614 (2,805 ) 664,905 Individual name issuer trust preferred debt securities 13,320 — (899 ) 12,421 Corporate bonds 13,715 32 (1,377 ) 12,370 Total available for sale debt securities $882,865 $9,573 ($5,418 ) $887,020 Total securities $882,865 $9,573 ($5,418 ) $887,020 (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) Available for Sale September 30, 2019 Amortized Cost Fair Value Due in one year or less $105,671 $106,401 Due after one year to five years 340,179 342,582 Due after five years to ten years 289,520 290,083 Due after ten years 147,495 147,954 Total debt securities $882,865 $887,020
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 September 30, 2019 # Fair Unrealized # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government-sponsored enterprises 3 $20,331 ($169 ) 4 $50,832 ($168 ) 7 $71,163 ($337 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 2 692 (1 ) 25 239,550 (2,804 ) 27 240,242 (2,805 ) Individual name issuer trust preferred debt securities — — — 5 12,421 (899 ) 5 12,421 (899 ) Corporate bonds — — — 3 10,425 (1,377 ) 3 10,425 (1,377 ) Total temporarily impaired securities 5 $21,023 ($170 ) 37 $313,228 ($5,248 ) 42 $334,251 ($5,418 ) (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) Three Months Nine Months For the periods ended September 30, 2019 2018 2019 2018 Proceeds from sales $— $— $9,920 $— Gross realized gains $— $— $— $— Gross realized losses — — (80 ) — Net realized losses on securities $— $— ($80 ) $—

Loans (Tables)

Loans (Tables)	9 Months Ended
	Sep. 30, 2019
Receivables [Abstract]
Summary of Loans	The following is a summary of loans: (Dollars in thousands) September 30, December 31, 2018 Commercial: Commercial real estate (1) $1,517,320 $1,392,408 Commercial & industrial (2) 566,426 620,704 Total commercial 2,083,746 2,013,112 Residential Real Estate: Residential real estate (3) 1,378,518 1,360,387 Consumer: Home equity 294,250 280,626 Other (4) 21,592 26,235 Total consumer 315,842 306,861 Total loans (5) $3,778,106 $3,680,360 (1) 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) Consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (3) Consists of mortgage and homeowner construction loans secured by one- to four-family residential properties. (4) Consists of loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 .
Past Due Loans	The following tables present an age analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due September 30, 2019 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Commercial real estate $— $— $684 $684 $1,516,636 $1,517,320 Commercial & industrial 1 — — 1 566,425 566,426 Total commercial 1 — 684 685 2,083,061 2,083,746 Residential Real Estate: Residential real estate 4,333 2,506 4,760 11,599 1,366,919 1,378,518 Consumer: Home equity 744 417 812 1,973 292,277 294,250 Other 11 — 88 99 21,493 21,592 Total consumer 755 417 900 2,072 313,770 315,842 Total loans $5,089 $2,923 $6,344 $14,356 $3,763,750 $3,778,106 (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 Sep 30, Dec 31, Sep 30, Dec 31, Sep 30, Dec 31, No Related Allowance Recorded Commercial: Commercial real estate $684 $925 $926 $926 $— $— Commercial & industrial — 4,681 — 4,732 — — Total commercial 684 5,606 926 5,658 — — Residential Real Estate: Residential real estate 12,531 9,347 13,368 9,695 — — Consumer: Home equity 1,379 1,360 1,379 1,360 — — Other 88 — 88 — — — Total consumer 1,467 1,360 1,467 1,360 — — Subtotal 14,682 16,313 15,761 16,713 — — With Related Allowance Recorded Commercial: Commercial real estate $— $— $— $— $— $— Commercial & industrial — 52 — 73 — — Total commercial — 52 — 73 — — Residential Real Estate: Residential real estate 360 364 386 390 96 100 Consumer: Home equity 220 85 220 85 220 24 Other 19 22 19 22 5 3 Total consumer 239 107 239 107 225 27 Subtotal 599 523 625 570 321 127 Total impaired loans $15,281 $16,836 $16,386 $17,283 $321 $127 Total: Commercial $684 $5,658 $926 $5,731 $— $— Residential real estate 12,891 9,711 13,754 10,085 96 100 Consumer 1,706 1,467 1,706 1,467 225 27 Total impaired loans $15,281 $16,836 $16,386 $17,283 $321 $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 tables present 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 Three months ended September 30, 2019 2018 2019 2018 Commercial: Commercial real estate $886 $— $— $— Commercial & industrial — 5,324 — 62 Total commercial 886 5,324 — 62 Residential Real Estate: Residential real estate 12,017 9,265 109 96 Consumer: Home equity 1,414 1,424 16 22 Other 108 25 3 — Total consumer 1,522 1,449 19 22 Totals $14,425 $16,038 $128 $180 (Dollars in thousands) Average Recorded Investment Interest Income Recognized Nine months ended September 30, 2019 2018 2019 2018 Commercial: Commercial real estate $929 $1,352 $1 $— Commercial & industrial 2,835 5,599 103 201 Total commercial 3,764 6,951 104 201 Residential Real Estate: Residential real estate 10,972 9,709 331 293 Consumer: Home equity 1,409 1,045 43 41 Other 55 85 2 5 Total consumer 1,464 1,130 45 46 Totals $16,200 $17,790 $480 $540
Nonaccrual Loans	The following is a summary of nonaccrual loans, segregated by class of loans: (Dollars in thousands) Sep 30, Dec 31, Commercial: Commercial real estate $684 $925 Commercial & industrial — — Total commercial 684 925 Residential Real Estate: Residential real estate 12,531 9,346 Consumer: Home equity 1,599 1,436 Other 88 — Total consumer 1,687 1,436 Total nonaccrual loans $14,902 $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 Sep 30, Dec 31, Sep 30, Dec 31, Sep 30, Dec 31, Commercial: Commercial real estate $1,498,212 $1,387,666 $18,224 $205 $884 $4,537 Commercial & industrial 529,219 559,019 25,679 50,426 11,528 11,259 Total commercial $2,027,431 $1,946,685 $43,903 $50,631 $12,412 $15,796
Credit Quality Indicators Residential & Consumer	The following table presents the residential and consumer loan portfolios, segregated by loan type and credit quality indicator: (Dollars in thousands) Current Past Due Sep 30, Dec 31, Sep 30, Dec 31, Residential Real Estate: Self-originated mortgages $1,261,364 $1,238,402 $10,503 $9,079 Purchased mortgages 105,555 111,465 1,096 1,441 Total residential real estate $1,366,919 $1,349,867 $11,599 $10,520 Consumer: Home equity $292,277 $278,637 $1,973 $1,989 Other 21,493 26,202 99 33 Total consumer $313,770 $304,839 $2,072 $2,022

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	9 Months Ended
	Sep. 30, 2019
Receivables [Abstract]
Allowance for Loan Losses Rollforward Analysis	The following table presents the activity in the allowance for loan losses for the three months ended September 30, 2019 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $16,882 $4,453 $21,335 $4,857 $913 $293 $1,206 $27,398 Charge-offs (947 ) (1 ) (948 ) — — (18 ) (18 ) (966 ) Recoveries — 123 123 — 36 6 42 165 Provision 866 (1,128 ) (262 ) 554 64 44 108 400 Ending Balance $16,801 $3,447 $20,248 $5,411 $1,013 $325 $1,338 $26,997 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the nine months ended September 30, 2019 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) 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 (947 ) (19 ) (966 ) (486 ) (372 ) (64 ) (436 ) (1,888 ) Recoveries — 151 151 — 71 16 87 238 Provision 2,367 (2,532 ) (165 ) 1,910 (289 ) 119 (170 ) 1,575 Ending Balance $16,801 $3,447 $20,248 $5,411 $1,013 $325 $1,338 $26,997 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the three months ended September 30, 2018 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) Total Commercial Residential Real Estate Home Equity Other Total Consumer Total Beginning Balance $12,443 $6,642 $19,085 $5,314 $1,375 $400 $1,775 $26,174 Charge-offs — (1 ) (1 ) (68 ) — (27 ) (27 ) (96 ) Recoveries — 71 71 — 2 8 10 81 Provision 1,052 535 1,587 (1,131 ) 12 (118 ) (106 ) 350 Ending Balance $13,495 $7,247 $20,742 $4,115 $1,389 $263 $1,652 $26,509 (1) Commercial real estate loans. (2) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the nine months ended September 30, 2018 : (Dollars in thousands) Commercial Consumer CRE (1) C&I (2) 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 ) (8 ) (635 ) (73 ) (111 ) (70 ) (181 ) (889 ) Recoveries 25 104 129 — 12 19 31 160 Provision 1,368 1,571 2,939 (1,239 ) (924 ) (26 ) (950 ) 750 Ending Balance $13,495 $7,247 $20,742 $4,115 $1,389 $263 $1,652 $26,509 (1) Commercial real estate loans. (2) Commercial & industrial loans.
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) September 30, 2019 December 31, 2018 Loans Related Allowance Loans Related Allowance Loans Individually Evaluated for Impairment Commercial: Commercial real estate $684 $— $925 $— Commercial & industrial — — 4,714 — Total commercial 684 — 5,639 — Residential Real Estate: Residential real estate 12,890 96 9,710 100 Consumer: Home equity 1,599 220 1,445 24 Other 107 5 22 3 Total consumer 1,706 225 1,467 27 Subtotal 15,280 321 16,816 127 Loans Collectively Evaluated for Impairment Commercial: Commercial real estate 1,516,636 16,801 1,391,483 15,381 Commercial & industrial 566,426 3,447 615,990 5,847 Total commercial 2,083,062 20,248 2,007,473 21,228 Residential Real Estate: Residential real estate 1,365,628 5,315 1,350,677 3,887 Consumer: Home equity 292,651 793 279,182 1,579 Other 21,485 320 26,212 251 Total consumer 314,136 1,113 305,394 1,830 Subtotal 3,762,826 26,676 3,663,544 26,945 Total $3,778,106 $26,997 $3,680,360 $27,072

Federal Home Loan Bank Advance

Federal Home Loan Bank Advance (Tables)	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
Federal Home Loan Bank Advances Maturity Summary	The following table presents maturities and weighted average interest rates on FHLB advances outstanding as of September 30, 2019 : (Dollars in thousands) Scheduled Weighted Average Rate October 1, 2019 to December 31, 2019 $355,822 2.56 % 2020 444,533 2.34 2021 86,222 2.73 2022 55,447 3.65 2023 9,428 4.01 2024 and thereafter 5,334 5.06 Balance at September 30, 2019 $956,786 2.56 %
Federal Home Loan Bank Advances Maturity Summary Modification	The table below presents the original terms as of September 30, 2019 , as well as the revised terms associated with these FHLB advances: (Dollars in thousands) Original Terms Revised Terms Scheduled Weighted Scheduled Weighted 2021 $20,000 3.07 % $— — % 2022 54,634 3.63 — — 2023 4,190 4.27 — — 2024 — — 40,000 2.45 2025 — — — — 2026 — — 38,824 3.09 Total $78,824 3.52 % $78,824 2.76 %

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2019
Broker-Dealer, Net Capital Requirement, SEC Regulation [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 Provisions Amount Ratio Amount Ratio Amount Ratio September 30, 2019 Total Capital (to Risk-Weighted Assets): Corporation $486,454 12.94 % $300,835 8.00 % N/A N/A Bank 483,783 12.87 300,790 8.00 $375,988 10.00 % Tier 1 Capital (to Risk-Weighted Assets): Corporation 459,140 12.21 225,627 6.00 N/A N/A Bank 456,469 12.14 225,593 6.00 300,790 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 437,142 11.62 169,220 4.50 N/A N/A Bank 456,469 12.14 169,195 4.50 244,392 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 459,140 8.97 204,810 4.00 N/A N/A Bank 456,469 8.92 204,722 4.00 255,903 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)	9 Months Ended
	Sep. 30, 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 Unaudited Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value Balance Sheet Location Sep 30, 2019 Dec 31, 2018 Balance Sheet Location Sep 30, 2019 Dec 31, 2018 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 2 903 Other liabilities 1,000 — Interest rate floors Other assets 69 37 Other liabilities — — Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Other assets 37,765 5,340 Other liabilities 80 7,719 Mirror swaps with counterparties Other assets 80 7,592 Other liabilities 37,913 5,392 Risk participation agreements Other assets 1 — Other liabilities 3 — Foreign exchange contracts Other assets 6 — Other liabilities — 7 Forward loan commitments: Interest rate lock commitments Other assets 1,762 806 Other liabilities 1 — Forward sale commitments Other assets 393 — Other liabilities 977 816 Gross amounts 40,078 14,698 39,974 13,934 Less amounts offset in Consolidated Balance Sheets (1) 157 10,732 157 10,732 Net amounts presented in Consolidated Balance Sheets 39,921 3,966 39,817 3,202 Less collateral pledged (2) — — 37,695 1,460 Net amounts $39,921 $3,966 $2,122 $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 Unaudited Consolidated Statements of Changes in Shareholders’ Equity and Unaudited Consolidated Statements of Income: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate caps $18 $17 $32 $66 Interest rate swaps (211 ) 189 (1,442 ) 1,322 Interest rate floors 22 (51 ) 175 21 Total ($171 ) $155 ($1,235 ) $1,409 For derivatives designated as cash flow hedging instruments, see Note 15 for additional disclosure pertaining to the amounts and location of reclassifications from accumulated other comprehensive income into earnings. (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivatives Three Months Nine Months Periods ended September 30, Statement of Income Location 2019 2018 2019 2018 Derivatives not Designated as Hedging Instruments: Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income $12,284 ($3,178 ) 39,568 (15,374 ) Mirror swaps with counterparties Loan related derivative income (11,108 ) 3,415 (36,958 ) 16,384 Risk participation agreements Loan related derivative income 213 25 213 25 Foreign exchange contracts Loan related derivative income 18 16 54 52 Forward loan commitments: Interest rate lock commitments Mortgage banking revenues (340 ) (504 ) $955 ($327 ) Forward sale commitments Mortgage banking revenues (101 ) 316 (1,969 ) 1,552 Total $966 $90 $1,863 $2,312

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 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) September 30, December 31, Aggregate fair value $44,657 $20,996 Aggregate principal balance 43,696 20,498 Difference between fair value and principal balance $961 $498
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 (Level 2) Significant Unobservable Inputs (Level 3) September 30, 2019 Assets: Available for sale debt securities: Obligations of U.S. government-sponsored enterprises $197,324 $— $197,324 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 664,905 — 664,905 — Individual name issuer trust preferred debt securities 12,421 — 12,421 — Corporate bonds 12,370 — 12,370 — Mortgage loans held for sale 44,657 — 44,657 — Derivative assets 39,921 — 39,921 — Total assets at fair value on a recurring basis $971,598 $— $971,598 $— Liabilities: Derivative liabilities $39,817 $— $39,817 $— Total liabilities at fair value on a recurring basis $39,817 $— $39,817 $— (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs 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 $—
Items Recorded at Fair Value on a Nonrecurring Basis	The following table presents the carrying value of assets held at September 30, 2019 , which were written down to fair value during the nine months ended September 30, 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 $1,451 $— $— $1,451 Property acquired through foreclosure or repossession 2,000 — — 2,000 Total assets at fair value on a nonrecurring basis $3,451 $— $— $3,451 The allowance for loan losses on collateral dependent impaired loans amounted to $221 thousand at September 30, 2019 . 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 .
Quantitative 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) September 30, 2019 Collateral dependent impaired loans $1,451 Appraisals of collateral Discount for costs to sell 0% - 18% (13%) Appraisal adjustments (1) 0% - 100% (19%) Property acquired through foreclosure or repossession $2,000 Appraisals of collateral Discount for costs to sell 20% Appraisal adjustments (1) 13% (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 and Estimated Fair Values 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) September 30, 2019 Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Financial Assets: Loans, net of allowance for loan losses $3,751,109 $3,749,391 $— $— $3,749,391 Financial Liabilities: Time deposits $1,223,662 $1,239,646 $— $1,239,646 $— FHLB advances 956,786 962,160 — 962,160 — Junior subordinated debentures 22,681 19,265 — 19,265 — (Dollars in thousands) December 31, 2018 Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs 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)	9 Months Ended
	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables summarize total revenues as presented in the Unaudited Consolidated Statements of Income and the related amounts which are from contracts with customers within the scope of Topic 606. As shown below, a substantial portion of our revenues are specifically excluded from the scope of Topic 606. For the three months ended September 30, 2019 2018 (Dollars in thousands) As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 Net interest income $32,978 $— $33,449 $— Noninterest income: Asset-based wealth management revenues 9,013 9,013 9,322 9,322 Transaction-based wealth management revenues 140 140 132 132 Total wealth management revenues 9,153 9,153 9,454 9,454 Mortgage banking revenues 4,840 — 2,624 — Card interchange fees 1,099 1,099 983 983 Service charges on deposit accounts 939 939 885 885 Loan related derivative income 1,407 — 278 — Income from bank-owned life insurance 569 — 572 — Net realized losses on securities — — — — Other income 335 323 419 419 Total noninterest income 18,342 11,514 15,215 11,741 Total revenues $51,320 $11,514 $48,664 $11,741 For the nine months ended September 30, 2019 2018 (Dollars in thousands) As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 As reported in Consolidated Statements of Income Revenue from contracts in scope of Topic 606 Net interest income $101,420 $— $98,412 $— Noninterest income: Asset-based wealth management revenues 27,075 27,075 28,413 28,413 Transaction-based wealth management revenues 879 879 916 916 Total wealth management revenues 27,954 27,954 29,329 29,329 Mortgage banking revenues 11,126 — 8,403 — Card interchange fees 3,114 3,114 2,791 2,791 Service charges on deposit accounts 2,743 2,743 2,651 2,651 Loan related derivative income 2,877 — 1,087 — Income from bank-owned life insurance 1,784 — 1,624 — Net realized losses on securities (80 ) — — — Other income 944 917 1,066 1,051 Total noninterest income 50,462 34,728 46,951 35,822 Total revenues $151,882 $34,728 $145,363 $35,822 The following table presents revenue from contracts with customers based on the timing of revenue recognition: (Dollars in thousands) Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Revenue recognized at a point in time: Card interchange fees $1,099 $983 $3,114 $2,791 Service charges on deposit accounts 728 670 2,109 2,045 Other income 268 258 771 732 Revenue recognized over time: Wealth management revenues 9,153 9,454 27,954 29,329 Service charges on deposit accounts 211 215 634 606 Other income 55 161 146 319 Total revenues from contracts in scope of Topic 606 $11,514 $11,741 $34,728 $35,822

Defined Benefit Pension Plans (

Defined Benefit Pension Plans (Tables)	9 Months Ended
	Sep. 30, 2019
Defined Benefit Plan [Abstract]
Components of Net Periodic Benefit Cost	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 Three Months Nine Months Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net Periodic Benefit Cost: Service cost (1) $510 $561 $1,528 $1,683 $31 $27 $94 $81 Interest cost (2) 741 679 2,225 2,036 140 119 422 356 Expected return on plan assets (2) (1,124 ) (1,318 ) (3,371 ) (3,954 ) — — — — Amortization of prior service credit (2) (4 ) (6 ) (12 ) (17 ) — — — — Recognized net actuarial loss (2) 198 374 594 1,122 104 103 307 308 Net periodic benefit cost $321 $290 $964 $870 $275 $249 $823 $745 (1) Included in salaries and employee benefits expense in the Unaudited Consolidated Statements of Income. (2) Included in other expenses in the Unaudited 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 net periodic benefit cost: Qualified Pension Plan Non-Qualified Retirement Plans For the nine months ended September 30, 2019 2018 2019 2018 Measurement date Dec 31, 2018 Dec 31, 2017 Dec 31, 2018 Dec 31, 2017 Equivalent single discount rate for benefit obligations 4.38% 3.69% 4.28% 3.58% Equivalent single discount rate for service cost 4.44 3.76 4.48 3.79 Equivalent single discount rate for interest cost 4.12 3.42 3.98 3.22 Expected long-term return on plan assets 5.75 6.75 N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75

Business Segments (Tables)

Business Segments (Tables)	9 Months Ended
	Sep. 30, 2019
Segment Reporting [Abstract]
Statement of Operations and Total Assets by Reportable Segment	The following table presents the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Commercial Banking Wealth Management Services Corporate Consolidated Total Three months ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net interest income (expense) $28,515 $27,036 ($114 ) ($90 ) $4,577 $6,503 $32,978 $33,449 Provision for loan losses 400 350 — — — — 400 350 Net interest income (expense) after provision for loan losses 28,115 26,686 (114 ) (90 ) 4,577 6,503 32,578 33,099 Noninterest income 8,607 5,174 9,153 9,454 582 587 18,342 15,215 Noninterest expenses: Depreciation and amortization expense 642 654 360 371 40 44 1,042 1,069 Other noninterest expenses 16,255 15,599 6,217 6,194 3,356 3,200 25,828 24,993 Total noninterest expenses 16,897 16,253 6,577 6,565 3,396 3,244 26,870 26,062 Income before income taxes 19,825 15,607 2,462 2,799 1,763 3,846 24,050 22,252 Income tax expense 4,347 3,344 646 710 243 687 5,236 4,741 Net income $15,478 $12,263 $1,816 $2,089 $1,520 $3,159 $18,814 $17,511 Total assets at period end $3,994,458 $3,694,991 $78,812 $69,494 $1,125,608 $1,006,187 $5,198,878 $4,770,672 Expenditures for long-lived assets 662 612 87 14 48 19 797 645 (Dollars in thousands) Commercial Banking Wealth Management Services Corporate Consolidated Total Nine months ended September 30, 2019 2018 2019 2018 2019 2018 2019 2018 Net interest income (expense) $83,684 $79,656 ($361 ) ($225 ) $18,097 $18,981 $101,420 $98,412 Provision for loan losses 1,575 750 — — — — 1,575 750 Net interest income (expense) after provision for loan losses 82,109 78,906 (361 ) (225 ) 18,097 18,981 99,845 97,662 Noninterest income 20,753 15,947 27,961 29,329 1,748 1,675 50,462 46,951 Noninterest expenses: Depreciation and amortization expense 1,985 1,928 1,089 1,137 118 129 3,192 3,194 Other noninterest expenses 48,676 46,574 19,631 19,986 10,486 9,726 78,793 76,286 Total noninterest expenses 50,661 48,502 20,720 21,123 10,604 9,855 81,985 79,480 Income before income taxes 52,201 46,351 6,880 7,981 9,241 10,801 68,322 65,133 Income tax expense 11,371 9,834 1,845 2,008 1,524 1,895 14,740 13,737 Net income $40,830 $36,517 $5,035 $5,973 $7,717 $8,906 $53,582 $51,396 Total assets at period end $3,994,458 $3,694,991 $78,812 $69,494 $1,125,608 $1,006,187 $5,198,878 $4,770,672 Expenditures for long-lived assets 2,259 1,864 379 327 130 129 2,768 2,320

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 2019
Equity [Abstract]
Activity in Other Comprehensive Income (Loss)	The following tables present the activity in other comprehensive income (loss): Three months ended September 30, 2019 2018 (Dollars in thousands) Pre-tax Amounts Income Taxes Net of Tax Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $3,772 $886 $2,886 ($5,924 ) ($1,393 ) ($4,531 ) Net losses on debt securities reclassified into earnings (1) — — — — — — Net change in fair value of available for sale debt securities 3,772 886 2,886 (5,924 ) (1,393 ) (4,531 ) Cash flow hedges: Change in fair value of cash flow hedges (283 ) (66 ) (217 ) (626 ) (148 ) (478 ) Net cash flow hedge losses reclassified into earnings (2) 60 14 46 830 197 633 Net change in fair value of cash flow hedges (223 ) (52 ) (171 ) 204 49 155 Defined benefit plan obligations: Amortization of net actuarial losses (3) 300 70 230 477 112 365 Amortization of net prior service credits (3) (4 ) (1 ) (3 ) (6 ) (2 ) (4 ) Net change in defined benefit plan obligations 296 69 227 471 110 361 Total other comprehensive income (loss) $3,845 $903 $2,942 ($5,249 ) ($1,234 ) ($4,015 ) (1) The pre-tax amount is reported as net realized losses on securities in the Unaudited 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 Unaudited Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Unaudited Consolidated Statements of Income. Nine months ended September 30, 2019 2018 (Dollars in thousands) Pre-tax Amounts Income Taxes Net of Tax Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of available for sale debt securities $25,985 $6,106 $19,879 ($23,605 ) ($5,548 ) ($18,057 ) Net losses on debt securities reclassified into earnings (1) 80 19 61 — — — Net change in fair value of available for sale debt securities 26,065 6,125 19,940 (23,605 ) (5,548 ) (18,057 ) Cash flow hedges: Change in fair value of cash flow hedges (1,653 ) (388 ) (1,265 ) 632 50 582 Net cash flow hedge losses reclassified into earnings (2) 39 9 30 1,082 255 827 Net change in fair value of cash flow hedges (1,614 ) (379 ) (1,235 ) 1,714 305 1,409 Defined benefit plan obligations: Amortization of net actuarial losses (3) 900 211 689 1,430 337 1,093 Amortization of net prior service credits (3) (12 ) (3 ) (9 ) (17 ) (5 ) (12 ) Net change in defined benefit plan obligations 888 208 680 1,413 332 1,081 Total other comprehensive (loss) income $25,339 $5,954 $19,385 ($20,478 ) ($4,911 ) ($15,567 ) (1) The pre-tax amount is reported as net realized losses on securities in the Unaudited 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 Unaudited Consolidated Statements of Income. (3) The pre-tax amounts are included in other expenses in the Unaudited Consolidated Statements of Income.
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 (Losses) Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total For the three months ended September 30, 2019 Balance at July 1, 2019 $292 ($873 ) ($11,285 ) ($11,866 ) Other comprehensive income (loss) before reclassifications 2,886 (217 ) — 2,669 Amounts reclassified from accumulated other comprehensive income — 46 227 273 Net other comprehensive income (loss) 2,886 (171 ) 227 2,942 Balance at September 30, 2019 $3,178 ($1,044 ) ($11,058 ) ($8,924 ) (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 For the nine months ended September 30, 2019 Balance at January 1, 2019 ($16,762 ) $191 ($11,738 ) ($28,309 ) Other comprehensive income (loss) before reclassifications 19,879 (1,265 ) — 18,614 Amounts reclassified from accumulated other comprehensive income 61 30 680 771 Net other comprehensive income (loss) 19,940 (1,235 ) 680 19,385 Balance at September 30, 2019 $3,178 ($1,044 ) ($11,058 ) ($8,924 ) (Dollars in thousands) Net Unrealized Losses on Available For Sale Debt Securities Net Unrealized Gains on Cash Flow Hedges Defined Benefit Pension Plan Adjustment Total For the three months ended September 30, 2018 Balance at July 1, 2018 ($21,060 ) $826 ($14,828 ) ($35,062 ) Other comprehensive loss before reclassifications (4,531 ) (478 ) — (5,009 ) Amounts reclassified from accumulated other comprehensive income — 633 361 994 Net other comprehensive (loss) income (4,531 ) 155 361 (4,015 ) Balance at September 30, 2018 ($25,591 ) $981 ($14,467 ) ($39,077 ) (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 For the nine months ended September 30, 2018 Balance at January 1, 2018 ($7,534 ) ($428 ) ($15,548 ) ($23,510 ) Other comprehensive (loss) income before reclassifications (18,057 ) 582 — (17,475 ) Amounts reclassified from accumulated other comprehensive income — 827 1,081 1,908 Net other comprehensive (loss) income (18,057 ) 1,409 1,081 (15,567 ) Balance at September 30, 2018 ($25,591 ) $981 ($14,467 ) ($39,077 )

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Calculation of Earnings Per Share	The following table presents the calculation of earnings per common share: (Dollars and shares in thousands, except per share amounts) Three Months Nine Months Periods ended September 30, 2019 2018 2019 2018 Earnings per common share - basic: Net income $18,814 $17,511 $53,582 $51,396 Less dividends and undistributed earnings allocated to participating securities (36 ) (36 ) (105 ) (112 ) Net income available to common shareholders $18,778 $17,475 $53,477 $51,284 Weighted average common shares 17,338 17,283 17,324 17,263 Earnings per common share - basic $1.08 $1.01 $3.09 $2.97 Earnings per common share - diluted: Net income $18,814 $17,511 $53,582 $51,396 Less dividends and undistributed earnings allocated to participating securities (36 ) (36 ) (105 ) (112 ) Net income available to common shareholders $18,778 $17,475 $53,477 $51,284 Weighted average common shares 17,338 17,283 17,324 17,263 Dilutive effect of common stock equivalents 76 99 82 129 Weighted average diluted common shares 17,414 17,382 17,406 17,392 Earnings per common share - diluted $1.08 $1.01 $3.07 $2.95

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 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 September 30, 2019 , including a reconciliation to the present value of operating lease liabilities recognized in the Corporation’s Unaudited Consolidated Balance Sheets: (Dollars in thousands) October 1, 2019 to December 31, 2019 $930 2020 3,515 2021 3,312 2022 3,165 2023 3,090 2024 and thereafter 24,716 Total operating lease payments (1) 38,728 Less interest 9,187 Present value of operating lease liabilities (2) $29,541 (1) Includes $4.2 million related to options to extend lease terms that are reasonably certain of being exercised. (2) Includes short-term operating lease liabilities of $2.3 million .
Schedule of total lease expense	The following table presents the components of total lease expense and operating cash flows: (Dollars in thousands) Periods ended September 30, 2019 Three Months Nine Months Lease Expense: Operating lease expense $931 $2,787 Variable lease expense 13 36 Total lease expense (1) $944 $2,823 Cash Paid: Cash paid reducing operating lease liabilities $926 $2,677 (1) Included in net occupancy expenses in the Unaudited Consolidated Income Statement.
Schedule of future minimum 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)	9 Months Ended
	Sep. 30, 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) Sep 30, Dec 31, Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $481,350 $533,884 Home equity lines 290,442 270,462 Other loans 74,931 46,698 Standby letters of credit 9,343 7,706 Financial instruments whose notional amounts exceed the amount of credit risk: Forward loan commitments: Interest rate lock commitments 84,820 30,766 Forward sale commitments 156,594 61,993 Loan related derivative contracts: Interest rate swaps with customers 729,913 648,050 Mirror swaps with counterparties 729,913 648,050 Risk participation-in agreements 73,040 46,510 Foreign exchange contracts 2,648 2,784 Interest rate risk management contracts: Interest rate swaps 60,000 60,000

Recently Issued Accounting Pr_2

Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Sep. 30, 2019		Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 28,900	$ 27,500			$ 0
Operating lease liabilities	30,900	29,541	[1]		0
Rent-related liabilities	2,900
Cumulative effect on retained earnings, tax	222
Cumulative effect on retained earnings, net of tax	722
Held to maturity debt securities, at amortized cost		0			10,415
Held to maturity debt securities, fair value		0			10,316
Unrealized losses on held to maturity securities, net of tax		$ (8,924)		$ (11,866)	$ (28,309)	$ (39,077)	$ (35,062)	$ (23,510)
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect on retained earnings, net of tax	$ 722
[1]	Includes short-term operating lease liabilities of $2.3 million .

Cash and Due from Banks (Narrat

Cash and Due from Banks (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Abstract]
Average reserve deposited with the Board of Governors of the Federal Reserve Bank	$ 27.6	$ 21.6
Interest-bearing deposits in other banks	$ 81.9	$ 33.7

Securities (Narrative) (Details

Securities (Narrative) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2019USD ($)security	Jun. 30, 2019USD ($)	Jan. 01, 2019USD ($)	Dec. 31, 2018USD ($)security	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2017USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Held to maturity debt securities, at amortized cost	$ 0			$ 10,415
Held to maturity debt securities, fair value	0			10,316
Unrealized losses on held to maturity securities, net of tax	(8,924)	$ (11,866)		(28,309)	$ (39,077)	$ (35,062)	$ (23,510)
Fair value of available for sale and held to maturity securities pledged as collateral	435,300			$ 439,700
Amortized cost of callable debt securities	222,500
Fair value of callable debt securities	$ 220,800
Number of securities in a continuous unrealized loss position total | security	42			90
Unrealized losses of securities in a continuous unrealized loss position total	$ (5,418)			$ (24,396)
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Number of securities in a continuous unrealized loss position total | security	5			5
Securities in unrealized loss position, number of companies issuing securities | security	4
Amortized cost of trust preferred securities of individual name issuers that are below investment grade	$ 6,100
Unrealized losses of trust preferred securities of individual name issuers that are below investment grade	458
Unrealized losses of securities in a continuous unrealized loss position total	$ (899)			$ (1,535)
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty 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	$ (1,377)			$ (1,777)
Minimum [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Maturity period of callable debt securities	3 months
Call features of callable debt securities	1 month
Maximum [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Maturity period of callable debt securities	17 years
Call features of callable debt securities	3 years
Adjustments for Change in Accounting Principle [Domain]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Held to maturity debt securities, at amortized cost			$ 10,400
Held to maturity debt securities, fair value			10,300
Unrealized losses on held to maturity securities, net of tax			$ (75)

Securities (Summary of Investme

Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	$ 882,865	$ 949,720
Available for sale debt securities unrealized gains	9,573	2,387
Available for sale debt securities unrealized losses	(5,418)	(24,297)
Available for sale debt securities, at fair value	887,020	927,810
Held to maturity debt securities	0	10,415
Held to maturity debt securities unrealized gains		0
Held to maturity debt securities unrealized losses		(99)
Held to maturity debt securities, fair value	0	10,316
Total securities amortized cost	882,865	960,135
Total securities unrealized gains	9,573	2,387
Total securities unrealized losses	(5,418)	(24,396)
Total securities fair value	887,020	938,126
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	196,734	246,708
Available for sale debt securities unrealized gains	927	442
Available for sale debt securities unrealized losses	(337)	(4,467)
Available for sale debt securities, at fair value	197,324	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 Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	659,096	675,368
Available for sale debt securities unrealized gains	8,614	1,943
Available for sale debt securities unrealized losses	(2,805)	(16,518)
Available for sale debt securities, at fair value	664,905	660,793
Held to maturity debt securities		10,415
Held to maturity debt securities unrealized gains		0
Held to maturity debt securities unrealized losses		(99)
Held to maturity debt securities, fair value		10,316
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	0	935
Available for sale debt securities unrealized gains	0	2
Available for sale debt securities unrealized losses	0	0
Available for sale debt securities, at fair value	0	937
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	13,320	13,307
Available for sale debt securities unrealized gains	0	0
Available for sale debt securities unrealized losses	(899)	(1,535)
Available for sale debt securities, at fair value	12,421	11,772
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities amortized cost basis	13,715	13,402
Available for sale debt securities unrealized gains	32	0
Available for sale debt securities unrealized losses	(1,377)	(1,777)
Available for sale debt securities, at fair value	$ 12,370	$ 11,625

Securities (Securities by Contr

Securities (Securities by Contractual Maturity) (Details) $ in Thousands	Sep. 30, 2019USD ($)
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale debt securities maturities within 1 year amortized cost	$ 105,671
Available for sale debt securities maturities 1-5 years amortized cost	340,179
Available for sale debt securities maturities 5-10 years amortized cost	289,520
Available for sale debt securities maturities after 10 years amortized cost	147,495
Available for sale debt securities maturities total amortized cost	882,865
Available for sale debt securities maturities within 1 year fair value	106,401
Available for sale debt securities maturities 1-5 years fair value	342,582
Available for sale debt securities maturities 5-10 years fair value	290,083
Available for sale debt securities maturities after 10 years fair value	147,954
Available for sale debt securities fair value	$ 887,020

Securities (Securities in a Con

Securities (Securities in a Continuous Unrealized Loss Position) (Details) $ in Thousands	Sep. 30, 2019USD ($)security	Dec. 31, 2018USD ($)security
Debt Securities, Available-for-sale [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	5	13
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 21,023	$ 48,258
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (170)	$ (448)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	37	77
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 313,228	$ 617,932
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (5,248)	$ (23,948)
Number of securities in a continuous unrealized loss position total | security	42	90
Fair value of securities in a continuous unrealized loss position total	$ 334,251	$ 666,190
Unrealized losses of securities in a continuous unrealized loss position total	$ (5,418)	$ (24,396)
Obligations of U.S. government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [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	$ 20,331	$ 0
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (169)	$ 0
Number of securities in a continuous unrealized loss position for 12 months or longer | security	4	16
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 50,832	$ 157,032
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (168)	$ (4,467)
Number of securities in a continuous unrealized loss position total | security	7	16
Fair value of securities in a continuous unrealized loss position total	$ 71,163	$ 157,032
Unrealized losses of securities in a continuous unrealized loss position total	$ (337)	$ (4,467)
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Debt Securities, Available-for-sale [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	2	10
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 692	$ 47,060
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (1)	$ (439)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	25	51
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 239,550	$ 438,701
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (2,804)	$ (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	$ 240,242	$ 485,761
Unrealized losses of securities in a continuous unrealized loss position total	$ (2,805)	$ (16,617)
Individual name issuer trust preferred debt securities
Debt Securities, Available-for-sale [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	$ 12,421	$ 11,772
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (899)	$ (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	$ 12,421	$ 11,772
Unrealized losses of securities in a continuous unrealized loss position total	$ (899)	$ (1,535)
Corporate bonds [Member]
Debt Securities, Available-for-sale [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	$ 10,425	$ 10,427
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (1,377)	$ (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	$ 10,425	$ 11,625
Unrealized losses of securities in a continuous unrealized loss position total	$ (1,377)	$ (1,777)

Securities Schedule of Amounts

Securities Schedule of Amounts from Sales of Securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Gain (Loss) on Securities [Line Items]
Proceeds from sales	$ 0	$ 0	$ 9,920	$ 0
Gross realized gains	0	0	0	0
Gross realized losses	0	0	(80)	0
Net realized losses on securities	$ 0	$ 0	$ (80)	$ 0

Loans (Narrative) (Details)

Loans (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Loans Receivable Net Deferred Cost Originated	$ 5,700	$ 4,700
Loans Receivable Net Deferred Premium on Purchased Loans	575	703
Loans Pledged as Collateral	2,000,000	2,000,000
Past due loans included in nonaccrual loans	9,800	8,600
Mortgage Loans in Process of Foreclosure	$ 5,900	$ 761

Loans (Summary of Loans) (Detai

Loans (Summary of Loans) (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[1]	$ 3,778,106	$ 3,680,360
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[2]	1,517,320	1,392,408
Commercial & Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[3]	566,426	620,704
Total Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		2,083,746	2,013,112
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[4]	1,378,518	1,360,387
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		294,250	280,626
Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[5]	21,592	26,235
Total Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 315,842	$ 306,861
[1]	Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 .
[2]	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]	Consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	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		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Total past due		$ 14,356	$ 13,622
Current		3,763,750	3,666,738
Total loans	[1]	3,778,106	3,680,360
30-59
Financing Receivable, Past Due [Line Items]
Total past due		5,089	7,787
60-89
Financing Receivable, Past Due [Line Items]
Total past due		2,923	3,774
Over 90
Financing Receivable, Past Due [Line Items]
Total past due		6,344	2,061
Commercial Real Estate
Financing Receivable, Past Due [Line Items]
Total past due		684	1,080
Current		1,516,636	1,391,328
Total loans	[2]	1,517,320	1,392,408
Commercial Real Estate | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		0	155
Commercial Real Estate | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		0	925
Commercial Real Estate | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		684	0
Commercial & Industrial
Financing Receivable, Past Due [Line Items]
Total past due		1	0
Current		566,425	620,704
Total loans	[3]	566,426	620,704
Commercial & Industrial | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		1	0
Commercial & Industrial | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		0	0
Commercial & Industrial | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		0	0
Total Commercial
Financing Receivable, Past Due [Line Items]
Total past due		685	1,080
Current		2,083,061	2,012,032
Total loans		2,083,746	2,013,112
Total Commercial | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		1	155
Total Commercial | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		0	925
Total Commercial | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		684	0
Residential Real Estate
Financing Receivable, Past Due [Line Items]
Total past due		11,599	10,520
Current		1,366,919	1,349,867
Total loans	[4]	1,378,518	1,360,387
Residential Real Estate | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		4,333	6,318
Residential Real Estate | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		2,506	2,693
Residential Real Estate | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		4,760	1,509
Home Equity
Financing Receivable, Past Due [Line Items]
Total past due		1,973	1,989
Current		292,277	278,637
Total loans		294,250	280,626
Home Equity | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		744	1,281
Home Equity | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		417	156
Home Equity | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		812	552
Other
Financing Receivable, Past Due [Line Items]
Total past due		99	33
Current		21,493	26,202
Total loans	[5]	21,592	26,235
Other | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		11	33
Other | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		0	0
Other | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		88	0
Total Consumer
Financing Receivable, Past Due [Line Items]
Total past due		2,072	2,022
Current		313,770	304,839
Total loans		315,842	306,861
Total Consumer | 30-59
Financing Receivable, Past Due [Line Items]
Total past due		755	1,314
Total Consumer | 60-89
Financing Receivable, Past Due [Line Items]
Total past due		417	156
Total Consumer | Over 90
Financing Receivable, Past Due [Line Items]
Total past due		$ 900	$ 552
[1]	Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 .
[2]	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]	Consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	Consists of loans to individuals secured by general aviation aircraft and other personal installment loans.

Loans (Impaired Loans) (Details

Loans (Impaired Loans) (Details) - USD ($)		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	$ 14,682,000	$ 16,313,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	599,000	523,000
Total Recorded Investment of Impaired Loans	[1]	15,281,000	16,836,000
Unpaid Principal of Impaired Loans with No Related Allowance		15,761,000	16,713,000
Unpaid Principal of Impaired Loans with Related Allowance		625,000	570,000
Total Unpaid Principal of Impaired Loans		16,386,000	17,283,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		321,000	127,000
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	684,000	925,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	0	0
Unpaid Principal of Impaired Loans with No Related Allowance		926,000	926,000
Unpaid Principal of Impaired Loans with Related Allowance		0	0
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	0
Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	4,681,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	0	52,000
Unpaid Principal of Impaired Loans with No Related Allowance		0	4,732,000
Unpaid Principal of Impaired Loans with Related Allowance		0	73,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	0
Total Commercial
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	684,000	5,606,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	0	52,000
Total Recorded Investment of Impaired Loans	[1]	684,000	5,658,000
Unpaid Principal of Impaired Loans with No Related Allowance		926,000	5,658,000
Unpaid Principal of Impaired Loans with Related Allowance		0	73,000
Total Unpaid Principal of Impaired Loans		926,000	5,731,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	0
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	12,531,000	9,347,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	360,000	364,000
Total Recorded Investment of Impaired Loans	[1]	12,891,000	9,711,000
Unpaid Principal of Impaired Loans with No Related Allowance		13,368,000	9,695,000
Unpaid Principal of Impaired Loans with Related Allowance		386,000	390,000
Total Unpaid Principal of Impaired Loans		13,754,000	10,085,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		96,000	100,000
Home Equity
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	1,379,000	1,360,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	220,000	85,000
Unpaid Principal of Impaired Loans with No Related Allowance		1,379,000	1,360,000
Unpaid Principal of Impaired Loans with Related Allowance		220,000	85,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		220,000	24,000
Other
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	88,000	0
Recorded Investment of Impaired Loans with Related Allowance	[1]	19,000	22,000
Unpaid Principal of Impaired Loans with No Related Allowance		88,000	0
Unpaid Principal of Impaired Loans with Related Allowance		19,000	22,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		5,000	3,000
Total Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	1,467,000	1,360,000
Recorded Investment of Impaired Loans with Related Allowance	[1]	239,000	107,000
Total Recorded Investment of Impaired Loans	[1]	1,706,000	1,467,000
Unpaid Principal of Impaired Loans with No Related Allowance		1,467,000	1,360,000
Unpaid Principal of Impaired Loans with Related Allowance		239,000	107,000
Total Unpaid Principal of Impaired Loans		1,706,000	1,467,000
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		$ 225,000	$ 27,000
[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 (Impaired Loans Interest

Loans (Impaired Loans Interest Income Recognized) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	$ 14,425	$ 16,038	$ 16,200	$ 17,790
Interest Income Recognized on Impaired Loans	128	180	480	540
Commercial Real Estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	886	0	929	1,352
Interest Income Recognized on Impaired Loans	0	0	1	0
Commercial & Industrial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	0	5,324	2,835	5,599
Interest Income Recognized on Impaired Loans	0	62	103	201
Total Commercial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	886	5,324	3,764	6,951
Interest Income Recognized on Impaired Loans	0	62	104	201
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	12,017	9,265	10,972	9,709
Interest Income Recognized on Impaired Loans	109	96	331	293
Home Equity
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	1,414	1,424	1,409	1,045
Interest Income Recognized on Impaired Loans	16	22	43	41
Other
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	108	25	55	85
Interest Income Recognized on Impaired Loans	3	0	2	5
Total Consumer
Financing Receivable, Impaired [Line Items]
Average Recorded Investment of Impaired Loans	1,522	1,449	1,464	1,130
Interest Income Recognized on Impaired Loans	$ 19	$ 22	$ 45	$ 46

Loans (Nonaccrual Loans) (Detai

Loans (Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 14,902	$ 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	5,100	3,100
Commercial Real Estate
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	684	925
Commercial & Industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	0	0
Total Commercial
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	684	925
Residential Real Estate
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	12,531	9,346
Home Equity
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	1,599	1,436
Other Consumer [Member]
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	88	0
Total Consumer
Financing Receivable, Past Due [Line Items]
Nonaccrual loans	$ 1,687	$ 1,436

Loans (Narrative - Troubled Deb

Loans (Narrative - Troubled Debt Restructurings) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Recorded investment in Troubled Debt Restructuring, Recorded Investment	$ 876	$ 5,600
Specific Reserves on Troubled Debt Restructurings	$ 101	$ 103

Loans Loans (Troubled Debt Rest

Loans Loans (Troubled Debt Restructurings Type of Modification) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)loan	Sep. 30, 2018USD ($)loan	Sep. 30, 2019USD ($)loan	Sep. 30, 2018USD ($)loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans modified as a troubled debt restructuring | loan	0	0	0	1
Troubled debt restructuring, pre-modification recorded investment	$ 0	$ 0	$ 0	$ 608
Troubled debt restructuring, post-modification recorded investment	$ 0	$ 0	$ 0	$ 608

Loans Loans (Troubled Debt Re_2

Loans Loans (Troubled Debt Restructurings Subsequent Default) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019USD ($)loan	Sep. 30, 2018USD ($)loan	Sep. 30, 2019USD ($)loan	Sep. 30, 2018USD ($)loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans modified as a troubled debt restructuring	0	0	0	1
Payment Default [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of loans modified as a troubled debt restructuring	0	1	0	1
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 0	$ 608	$ 0	$ 608

Loans (Credit Quality Indicator

Loans (Credit Quality Indicators - Commercial) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Commercial Real Estate | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	$ 1,498,212	$ 1,387,666
Commercial Real Estate | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	18,224	205
Commercial Real Estate | Classified [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	884	4,537
Commercial & Industrial | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	529,219	559,019
Commercial & Industrial | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	25,679	50,426
Commercial & Industrial | Classified [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	11,528	11,259
Total Commercial | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	2,027,431	1,946,685
Total Commercial | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	43,903	50,631
Total Commercial | Classified [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans Receivable	$ 12,412	$ 15,796

Loans (Credit Quality Indicat_2

Loans (Credit Quality Indicators - Residential, Consumer) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Current	$ 3,763,750	$ 3,666,738
Total past due	14,356	13,622
Self-originated Mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1,261,364	1,238,402
Total past due	10,503	9,079
Purchased Mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Current	105,555	111,465
Total past due	1,096	1,441
Residential Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current	1,366,919	1,349,867
Total past due	11,599	10,520
Home Equity
Financing Receivable, Credit Quality Indicator [Line Items]
Current	292,277	278,637
Total past due	1,973	1,989
Other
Financing Receivable, Credit Quality Indicator [Line Items]
Current	21,493	26,202
Total past due	99	33
Total Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Current	313,770	304,839
Total past due	$ 2,072	$ 2,022

Allowance for Loan Losses (All

Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		$ 27,398	$ 26,174	$ 27,072	$ 26,488
Charge-offs		(966)	(96)	(1,888)	(889)
Recoveries		165	81	238	160
Provision		400	350	1,575	750
Allowance, Ending Balance		26,997	26,509	26,997	26,509
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	[1]	16,882	12,443	15,381	12,729
Charge-offs	[1]	(947)	0	(947)	(627)
Recoveries	[1]	0	0	0	25
Provision	[1]	866	1,052	2,367	1,368
Allowance, Ending Balance	[1]	16,801	13,495	16,801	13,495
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance	[2]	4,453	6,642	5,847	5,580
Charge-offs	[2]	(1)	(1)	(19)	(8)
Recoveries	[2]	123	71	151	104
Provision	[2]	(1,128)	535	(2,532)	1,571
Allowance, Ending Balance	[2]	3,447	7,247	3,447	7,247
Total Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		21,335	19,085	21,228	18,309
Charge-offs		(948)	(1)	(966)	(635)
Recoveries		123	71	151	129
Provision		(262)	1,587	(165)	2,939
Allowance, Ending Balance		20,248	20,742	20,248	20,742
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		4,857	5,314	3,987	5,427
Charge-offs		0	(68)	(486)	(73)
Recoveries		0	0	0	0
Provision		554	(1,131)	1,910	(1,239)
Allowance, Ending Balance		5,411	4,115	5,411	4,115
Home Equity
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		913	1,375	1,603	2,412
Charge-offs		0	0	(372)	(111)
Recoveries		36	2	71	12
Provision		64	12	(289)	(924)
Allowance, Ending Balance		1,013	1,389	1,013	1,389
Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		293	400	254	340
Charge-offs		(18)	(27)	(64)	(70)
Recoveries		6	8	16	19
Provision		44	(118)	119	(26)
Allowance, Ending Balance		325	263	325	263
Total Consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Allowance, Beginning Balance		1,206	1,775	1,857	2,752
Charge-offs		(18)	(27)	(436)	(181)
Recoveries		42	10	87	31
Provision		108	(106)	(170)	(950)
Allowance, Ending Balance		$ 1,338	$ 1,652	$ 1,338	$ 1,652
[1]	Commercial real estate loans.
[2]	Commercial & industrial loans.

Allowance for Loan Losses (Allo

Allowance for Loan Losses (Allowance for Loan Losses by Segment & Impairment Methodology) (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		$ 15,280	$ 16,816
Loans related allowance individually evaluated for impairment		321	127
Loans collectively evaluated for impairment		3,762,826	3,663,544
Loans related allowance collectively evaluated for impairment		26,676	26,945
Total loans	[1]	3,778,106	3,680,360
Allowance		26,997	27,072
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		684	925
Loans related allowance individually evaluated for impairment		0	0
Loans collectively evaluated for impairment		1,516,636	1,391,483
Loans related allowance collectively evaluated for impairment		16,801	15,381
Total loans	[2]	1,517,320	1,392,408
Commercial & Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		0	4,714
Loans related allowance individually evaluated for impairment		0	0
Loans collectively evaluated for impairment		566,426	615,990
Loans related allowance collectively evaluated for impairment		3,447	5,847
Total loans	[3]	566,426	620,704
Total Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		684	5,639
Loans related allowance individually evaluated for impairment		0	0
Loans collectively evaluated for impairment		2,083,062	2,007,473
Loans related allowance collectively evaluated for impairment		20,248	21,228
Total loans		2,083,746	2,013,112
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		12,890	9,710
Loans related allowance individually evaluated for impairment		96	100
Loans collectively evaluated for impairment		1,365,628	1,350,677
Loans related allowance collectively evaluated for impairment		5,315	3,887
Total loans	[4]	1,378,518	1,360,387
Home Equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		1,599	1,445
Loans related allowance individually evaluated for impairment		220	24
Loans collectively evaluated for impairment		292,651	279,182
Loans related allowance collectively evaluated for impairment		793	1,579
Total loans		294,250	280,626
Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		107	22
Loans related allowance individually evaluated for impairment		5	3
Loans collectively evaluated for impairment		21,485	26,212
Loans related allowance collectively evaluated for impairment		320	251
Total loans	[5]	21,592	26,235
Total Consumer
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans individually evaluated for impairment		1,706	1,467
Loans related allowance individually evaluated for impairment		225	27
Loans collectively evaluated for impairment		314,136	305,394
Loans related allowance collectively evaluated for impairment		1,113	1,830
Total loans		$ 315,842	$ 306,861
[1]	Includes net unamortized loan origination costs of $5.7 million and $4.7 million , respectively, at September 30, 2019 and December 31, 2018 and net unamortized premiums on purchased loans of $575 thousand and $703 thousand , respectively, at September 30, 2019 and December 31, 2018 .
[2]	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]	Consists of loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[4]	Consists of mortgage and homeowner construction loans secured by one- to four-family residential properties.
[5]	Consists of loans to individuals secured by general aviation aircraft and other personal installment loans.

Federal Home Loan Bank Advanc_2

Federal Home Loan Bank Advances (Narrative Federal Home Loan Bank Advances) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Federal Home Loan Bank advances	$ 956,786	$ 950,722
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Federal Home Loan Bank advances	956,786	950,700
Unused line of credit with FHLBB	40,000	40,000
Unused remaining available borrowing capacity with FHLBB	$ 601,500	$ 628,500
Total weighted average rate	2.56%
Original Terms of FHLBB Advance Restructuring [Member] | Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Federal Home Loan Bank advances	$ 78,824
Total weighted average rate	3.52%
Revised Terms of FHLBB Advance Restructuring [Member] | Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Federal Home Loan Bank advances	$ 78,824
Total weighted average rate	2.76%

Federal Home Loan Bank Advanc_3

Federal Home Loan Bank Advances (Federal Home Loan Bank Advances Maturity Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Federal Home Loan Bank advances	$ 956,786	$ 950,722
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLBB Bank [Line Items]
Scheduled maturity through the end of the current year	$ 355,822
Weighted average rate for scheduled maturity through the end of the current year	2.56%
Scheduled maturity in year two	$ 444,533
Weighted average rate for scheduled maturity in year two	2.34%
Scheduled maturity in year three	$ 86,222
Weighted average rate for scheduled maturity in year three	2.73%
Scheduled maturity in year four	$ 55,447
Weighted average rate for scheduled maturity in year four	3.65%
Scheduled maturity in year five	$ 9,428
Weighted average rate for scheduled maturity in year five	4.01%
Scheduled maturity after year five	$ 5,334
Weighted average rate for scheduled maturity after year five	5.06%
Federal Home Loan Bank advances	$ 956,786	$ 950,700
Total weighted average rate	2.56%

Federal Home Loan Bank Advanc_4

Federal Home Loan Bank Advances (Federal Home Loan Bank Advances Modification Maturity Schedule) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Federal Home Loan Bank, Advances [Line Items]
Federal Home Loan Bank advances	$ 956,786	$ 950,722
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances [Line Items]
Scheduled maturity in year three	$ 86,222
Weighted average rate for scheduled maturity in year three	2.73%
Scheduled maturity in year four	$ 55,447
Weighted average rate for scheduled maturity in year four	3.65%
Scheduled maturity in year five	$ 9,428
Weighted average rate for scheduled maturity in year five	4.01%
Federal Home Loan Bank advances	$ 956,786	$ 950,700
Total weighted average rate	2.56%
Original Terms of FHLBB Advance Restructuring [Member] | Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances [Line Items]
Scheduled maturity in year three	$ 20,000
Weighted average rate for scheduled maturity in year three	3.07%
Scheduled maturity in year four	$ 54,634
Weighted average rate for scheduled maturity in year four	3.63%
Scheduled maturity in year five	$ 4,190
Weighted average rate for scheduled maturity in year five	4.27%
Scheduled maturity in year six	$ 0
Weighted average rate for schedule maturity in year six	0.00%
Scheduled maturity in year seven	$ 0
Weighted average rate for schedule maturity in year seven	0.00%
Scheduled maturity in year eight	$ 0
Weighted average rate for schedule maturity in year eight	0.00%
Federal Home Loan Bank advances	$ 78,824
Total weighted average rate	3.52%
Revised Terms of FHLBB Advance Restructuring [Member] | Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances [Line Items]
Scheduled maturity in year three	$ 0
Weighted average rate for scheduled maturity in year three	0.00%
Scheduled maturity in year four	$ 0
Weighted average rate for scheduled maturity in year four	0.00%
Scheduled maturity in year five	$ 0
Weighted average rate for scheduled maturity in year five	0.00%
Scheduled maturity in year six	$ 40,000
Weighted average rate for schedule maturity in year six	2.45%
Scheduled maturity in year seven	$ 0
Weighted average rate for schedule maturity in year seven	0.00%
Scheduled maturity in year eight	$ 38,824
Weighted average rate for schedule maturity in year eight	3.09%
Federal Home Loan Bank advances	$ 78,824
Total weighted average rate	2.76%

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Trust preferred securities included in Tier 1 Capital	$ 22	$ 22

Shareholders' Equity (Regulator

Shareholders' Equity (Regulatory Captial Requirements) (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Corporation [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital		$ 486,454	$ 455,699
Total Capital to Risk-Weighted Assets		12.94%	12.56%
Total Capital for Capital Adequacy Purposes		$ 300,835	$ 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		$ 459,140	$ 428,338
Tier 1 Capital to Risk Weighted-Assets		12.21%	11.81%
Tier 1 Capital Required For Capital Adequacy Purposes		$ 225,627	$ 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		$ 437,142	$ 406,340
Common Equity Tier 1 Capital to Risk Weighted Assets		11.62%	11.20%
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 169,220	$ 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	[1]	$ 459,140	$ 428,338
Tier 1 Leverage Capital to Average Assets	[1]	8.97%	8.89%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	[1]	$ 204,810	$ 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		$ 483,783	$ 453,033
Total Capital to Risk-Weighted Assets		12.87%	12.49%
Total Capital for Capital Adequacy Purposes		$ 300,790	$ 290,128
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets		8.00%	8.00%
Total Capital To Be Well Capitalized		$ 375,988	$ 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		$ 456,469	$ 425,672
Tier 1 Capital to Risk Weighted-Assets		12.14%	11.74%
Tier 1 Capital Required For Capital Adequacy Purposes		$ 225,593	$ 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		$ 300,790	$ 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		$ 456,469	$ 425,672
Common Equity Tier 1 Capital to Risk Weighted Assets		12.14%	11.74%
Common Equity Tier 1 Capital Required for Capital Adequacy		$ 169,195	$ 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		$ 244,392	$ 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	[1]	$ 456,469	$ 425,672
Tier 1 Leverage Capital to Average Assets	[1]	8.92%	8.84%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	[1]	$ 204,722	$ 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	[1]	$ 255,903	$ 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	Sep. 30, 2019USD ($)derivative_instrument	Dec. 31, 2018USD ($)derivative_instrument
Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 60,000	$ 60,000
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	729,913	648,050
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	729,913	648,050
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	73,040	46,510
Foreign exchange contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	2,648	2,784
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	84,820	30,766
Forward sale commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	156,594	61,993
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate caps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 22,700	$ 22,681
Number of instruments held | derivative_instrument	2	2
Interest rate cap interest rate	4.50%	4.50%
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 60,000	$ 60,000
Number of instruments held | derivative_instrument	2	2
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate floors [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 300,000	$ 300,000
Number of instruments held | derivative_instrument	3	3
Interest rate floor interest rate	1.00%	1.00%
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 729,900	$ 648,000
Not Designated as Hedging Instrument [Member] | Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	729,913	648,049
Not Designated as Hedging Instrument [Member] | Risk participation-out agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	44,500	57,300
Not Designated as Hedging Instrument [Member] | Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	73,000	46,500
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 2,600	$ 2,800

Derivative Financial Instrume_4

Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Derivative Financial Instruments, Assets [Member]
Derivatives, Fair Value [Line Items]
Gross derivative positions		$ 40,078	$ 14,698
Amounts offset in balance sheet	[1]	157	10,732
Net amounts presented in balance sheet		39,921	3,966
Collateral pledged	[2]	0	0
Net amounts		39,921	3,966
Derivative Financial Instruments, Liabilities [Member]
Derivatives, Fair Value [Line Items]
Gross derivative positions		39,974	13,934
Amounts offset in balance sheet	[1]	157	10,732
Net amounts presented in balance sheet		39,817	3,202
Collateral pledged	[2]	37,695	1,460
Net amounts		2,122	1,742
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate caps [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets designated as a cash flow hedge		0	20
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate caps [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities designated as a cash flow hedge		0	0
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate swaps [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets designated as a cash flow hedge		2	903
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate swaps [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities designated as a cash flow hedge		1,000	0
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate floors [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets designated as a cash flow hedge		69	37
Derivatives Designated as Cash Flow Hedging Instruments [Member] | Interest rate floors [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities designated as a cash flow hedge		0	0
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		37,765	5,340
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		80	7,719
Not Designated as Hedging Instrument [Member] | Mirror swaps with counterparties [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		80	7,592
Not Designated as Hedging Instrument [Member] | Mirror swaps with counterparties [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		37,913	5,392
Not Designated as Hedging Instrument [Member] | Risk participation agreements [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		1	0
Not Designated as Hedging Instrument [Member] | Risk participation agreements [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		3	0
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		6	0
Not Designated as Hedging Instrument [Member] | Foreign exchange contracts [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		0	7
Not Designated as Hedging Instrument [Member] | Interest rate lock commitments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		1,762	806
Not Designated as Hedging Instrument [Member] | Interest rate lock commitments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		1	0
Not Designated as Hedging Instrument [Member] | Forward sale commitments [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets not designated		393	0
Not Designated as Hedging Instrument [Member] | Forward sale commitments [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities not designated		$ 977	$ 816
[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 Income and Changes in Shareholders' Equity) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	$ (171)	$ 155	$ (1,235)	$ 1,409
Interest rate caps [Member] | Cash Flow Hedge [Member] | Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	18	17	32	66
Interest rate swaps [Member] | Cash Flow Hedge [Member] | Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	(211)	189	(1,442)	1,322
Interest rate floors [Member] | Cash Flow Hedge [Member] | Other Comprehensive Income (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net change in fair value of cash flow hedges	$ 22	$ (51)	$ 175	$ 21

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	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	$ 966	$ 90	$ 1,863	$ 2,312
Interest rate swaps with customers [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	12,284	(3,178)	39,568	(15,374)
Mirror swaps with counterparties [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	(11,108)	3,415	(36,958)	16,384
Risk participation agreements [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	213	25	213	25
Foreign exchange contracts [Member] | Loan related derivative income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	18	16	54	52
Interest rate lock commitments [Member] | Mortgage banking revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	(340)	(504)	955	(327)
Forward sale commitments [Member] | Mortgage banking revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income	$ (101)	$ 316	$ (1,969)	$ 1,552

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands		Aug. 01, 2015	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payment of contingent consideration liability			$ 0	$ 1,217
Contingent consideration liability					$ 0
Recorded Investment of Impaired Loans with Related Allowance	[1]		599		523
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Recorded Investment of Impaired Loans with Related Allowance			1,451		883
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Recorded Investment of Impaired Loans with Related Allowance			1,451		883
Allowance For Loan Loss Allocation on Collateral Dependent Impaired Loans			$ 221		$ 24
Contingent Consideration [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earn-out period post acquisition		5 years
[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 (Fair V

Fair Value Measurements (Fair Value Mortgage Loans Held For Sale Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Mortgage loans held for sale, measured at fair value	$ 44,657		$ 44,657		$ 20,996
Mortgage loans held for sale, amortized cost	43,696		43,696		20,498
Mortgage loans held for sale, difference between fair value and amortized cost	961		961		$ 498
Mortgage Loans Held for Sale [Member]
Change in fair value under fair value option election	$ (82)	$ (352)	$ 462	$ (240)

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	$ 887,020	$ 927,810
Mortgage loans held for sale, measured at fair value	44,657	20,996
Obligations of U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	197,324	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 debt securities, at fair value	664,905	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 debt securities, at fair value	0	937
Individual name issuer trust preferred debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	12,421	11,772
Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	12,370	11,625
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, measured at fair value	44,657	20,996
Derivative assets	39,921	3,966
Total assets at fair value on a recurring basis	971,598	952,772
Derivative liabilities	39,817	3,202
Total liabilities at fair value on a recurring basis	39,817	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 debt securities, at fair value	197,324	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 debt securities, at fair value	664,905	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 debt securities, at fair value	0	937
Recurring [Member] | Individual name issuer trust preferred debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	12,421	11,772
Recurring [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	12,370	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, measured at 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 debt securities, at fair value	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 debt securities, at fair value	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 debt securities, at fair value	0	0
Recurring [Member] | Level 1 [Member] | Individual name issuer trust preferred debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	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 debt securities, at fair value	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, measured at fair value	44,657	20,996
Derivative assets	39,921	3,966
Total assets at fair value on a recurring basis	971,598	952,772
Derivative liabilities	39,817	3,202
Total liabilities at fair value on a recurring basis	39,817	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 debt securities, at fair value	197,324	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 debt securities, at fair value	664,905	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 debt securities, at fair value		937
Recurring [Member] | Level 2 [Member] | Individual name issuer trust preferred debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	12,421	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 debt securities, at fair value	12,370	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, measured at 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 debt securities, at fair value	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 debt securities, at fair value	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 debt securities, at fair value	0	0
Recurring [Member] | Level 3 [Member] | Individual name issuer trust preferred debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale debt securities, at fair value	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 debt securities, at fair value	$ 0	$ 0

Fair Value Measurements (Asset

Fair Value Measurements (Asset and Liabilities Measured on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	[1]	$ 599	$ 523
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		1,451	883
Property acquired through foreclosure or repossession		2,000	2,142
Total assets at fair value on a nonrecurring basis		3,451	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 nonrecurring 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 nonrecurring 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		1,451	883
Property acquired through foreclosure or repossession		2,000	2,142
Total assets at fair value on a nonrecurring basis		$ 3,451	$ 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		9 Months Ended	12 Months Ended
		Sep. 30, 2019	Dec. 31, 2018
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans	[1]	$ 599	$ 523
Nonrecurring [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans		1,451	883
Property acquired through foreclosure or repossession		2,000	2,142
Nonrecurring [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans		1,451	883
Property acquired through foreclosure or repossession		$ 2,000	$ 2,142
Nonrecurring [Member] | Minimum [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		0.00%
Nonrecurring [Member] | Minimum [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	0.00%
Appraisal adjustments	[2]	0.00%
Nonrecurring [Member] | Minimum [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		20.00%	13.00%
Appraisal adjustments	[2]	13.00%	12.00%
Nonrecurring [Member] | Maximum [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		100.00%
Nonrecurring [Member] | Maximum [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		18.00%	10.00%
Appraisal adjustments	[2]	100.00%
Nonrecurring [Member] | Maximum [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		20.00%	13.00%
Appraisal adjustments	[2]	13.00%	28.00%
Nonrecurring [Member] | Weighted Average [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		2.00%
Nonrecurring [Member] | Weighted Average [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		13.00%	10.00%
Appraisal adjustments	[2]	19.00%
Nonrecurring [Member] | Weighted Average [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		20.00%	13.00%
Appraisal adjustments	[2]	13.00%	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.
[2]	Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property.

Fair Value Measurements (Carryi

Fair Value Measurements (Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity debt securities	$ 0	$ 10,415
Loans, net of allowance of loan losses	3,751,109	3,653,288
Federal Home Loan Bank advances	956,786	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 debt securities		10,415
Loans, net of allowance of loan losses	3,751,109	3,653,288
Time deposits	1,223,662	1,255,108
Federal Home Loan Bank advances	956,786	950,722
Junior subordinated debentures	22,681	22,681
Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity debt securities		10,316
Loans, net of allowance of loan losses	3,749,391	3,598,025
Time deposits	1,239,646	1,269,433
Federal Home Loan Bank advances	962,160	950,691
Junior subordinated debentures	19,265	19,226
Fair Value Measurement [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity debt securities		0
Loans, net of allowance of loan losses	0	0
Time deposits	0	0
Federal Home Loan Bank advances	0	0
Junior subordinated debentures	0	0
Fair Value Measurement [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity debt securities		10,316
Loans, net of allowance of loan losses	0	0
Time deposits	1,239,646	1,269,433
Federal Home Loan Bank advances	962,160	950,691
Junior subordinated debentures	19,265	19,226
Fair Value Measurement [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity debt securities		0
Loans, net of allowance of loan losses	3,749,391	3,598,025
Time deposits	0	0
Federal Home Loan Bank advances	0	0
Junior subordinated debentures	$ 0	$ 0

Revenue from Contracts with C_3

Revenue from Contracts with Customers (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Receivables from contracts with customers	$ 4,800	$ 4,800
Contract cost assets	$ 683	$ 458

Revenue from Contracts with C_4

Revenue from Contracts with Customers (Disaggregation of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Net interest income	$ 32,978	$ 33,449	$ 101,420	$ 98,412
Asset-based wealth management revenues	9,013	9,322	27,075	28,413
Transaction-based wealth management revenues	140	132	879	916
Wealth management revenues	9,153	9,454	27,954	29,329
Mortgage banking revenues	4,840	2,624	11,126	8,403
Card interchange fees	1,099	983	3,114	2,791
Service charges on deposit accounts	939	885	2,743	2,651
Loan related derivative income	1,407	278	2,877	1,087
Income from bank-owned life insurance	569	572	1,784	1,624
Net realized losses on securities	0	0	(80)	0
Other income	335	419	944	1,066
Total noninterest income	18,342	15,215	50,462	46,951
Total revenues	51,320	48,664	151,882	145,363
Revenue from contracts in scope of Topic 606	11,514	11,741	34,728	35,822
Net Interest Income
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	0	0	0	0
Asset-based Wealth Management Revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	9,013	9,322	27,075	28,413
Transaction-based Wealth Management Revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	140	132	879	916
Total Wealth Management Revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	9,153	9,454	27,954	29,329
Mortgage Banking Revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	0	0	0	0
Card Interchange Fees
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	1,099	983	3,114	2,791
Service Charges on Deposit Accounts
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	939	885	2,743	2,651
Loan Related Derivative Income
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	0	0	0	0
Income From Bank-owned Life Insurance
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	0	0	0	0
Net Realized Gains (Losses) on Securities
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	0	0	0	0
Other Income
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	323	419	917	1,051
Total Noninterest Income
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	11,514	11,741	34,728	35,822
Total Revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts in scope of Topic 606	$ 11,514	$ 11,741	$ 34,728	$ 35,822

Revenue from Contracts with C_5

Revenue from Contracts with Customers (Disaggregation by Timing of Revenue Recognition) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue from contracts in scope of Topic 606	$ 11,514	$ 11,741	$ 34,728	$ 35,822
Wealth Management Revenues
Revenue from contracts in scope of Topic 606	9,153	9,454	27,954	29,329
Wealth Management Revenues | Transferred over Time [Member]
Revenue from contracts in scope of Topic 606	9,153	9,454	27,954	29,329
Card Interchange Fees
Revenue from contracts in scope of Topic 606	1,099	983	3,114	2,791
Card Interchange Fees | Transferred at Point in Time [Member]
Revenue from contracts in scope of Topic 606	1,099	983	3,114	2,791
Service Charges on Deposit Accounts
Revenue from contracts in scope of Topic 606	939	885	2,743	2,651
Service Charges on Deposit Accounts | Transferred at Point in Time [Member]
Revenue from contracts in scope of Topic 606	728	670	2,109	2,045
Service Charges on Deposit Accounts | Transferred over Time [Member]
Revenue from contracts in scope of Topic 606	211	215	634	606
Other Income
Revenue from contracts in scope of Topic 606	323	419	917	1,051
Other Income | Transferred at Point in Time [Member]
Revenue from contracts in scope of Topic 606	268	258	771	732
Other Income | Transferred over Time [Member]
Revenue from contracts in scope of Topic 606	$ 55	$ 161	$ 146	$ 319

Defined Benefit Pension Plans_2

Defined Benefit Pension Plans (Narrative) (Details)	120 Months Ended
	Dec. 30, 2023
Forecast [Member]
Transition Period Pension Plan Amendment	10 years

Defined Benefit Pension Plans_3

Defined Benefit Pension Plans (Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Qualified Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	[1]	$ 510	$ 561	$ 1,528	$ 1,683
Interest cost	[2]	741	679	2,225	2,036
Expected return on plan assets	[2]	(1,124)	(1,318)	(3,371)	(3,954)
Amortization of prior service (credit) cost	[2]	(4)	(6)	(12)	(17)
Recognized net actuarial loss	[2]	198	374	594	1,122
Net periodic benefit cost		321	290	964	870
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	[1]	31	27	94	81
Interest cost	[2]	140	119	422	356
Expected return on plan assets	[2]	0	0	0	0
Amortization of prior service (credit) cost	[2]	0	0	0	0
Recognized net actuarial loss	[2]	104	103	307	308
Net periodic benefit cost		$ 275	$ 249	$ 823	$ 745
[1]	Included in salaries and employee benefits expense in the Unaudited Consolidated Statements of Income.
[2]	Included in other expenses in the Unaudited Consolidated Statements of Income.

Defined Benefit Pension Plans_4

Defined Benefit Pension Plans (Weighted-Average Assumptions Used) (Details)	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Qualified Pension Plan [Member]
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%
Equivalent single discount rate for service cost	4.44%	3.76%
Equivalent single discount rate for interest cost	4.12%	3.42%
Expected long-term return on plan assets	5.75%	6.75%
Rate of compensation increase	3.75%	3.75%
Non-Qualified Retirement Plans [Member]
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%
Equivalent single discount rate for service cost	4.48%	3.79%
Equivalent single discount rate for interest cost	3.98%	3.22%
Rate of compensation increase	3.75%	3.75%

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details)	9 Months Ended
	Sep. 30, 2019$ / sharesshares
Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards, grant date fair value | $ / shares	$ 52.83
Award vesting period	3 years
Performance share awards, shares vesting | shares	43,360
Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Nonvested share units granted | shares	10,870
Nonvested share units weighted average grant date fair value | $ / shares	$ 51.43

Business Segments (Statement of

Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net interest income (expense)	$ 32,978	$ 33,449	$ 101,420	$ 98,412
Provision for loan losses	400	350	1,575	750
Net interest income after provision for loan losses	32,578	33,099	99,845	97,662
Noninterest income	18,342	15,215	50,462	46,951
Depreciation and amortization expense	1,042	1,069	3,192	3,194
Other noninterest expenses related to segments	25,828	24,993	78,793	76,286
Total noninterest expense	26,870	26,062	81,985	79,480
Income before income taxes	24,050	22,252	68,322	65,133
Income tax expense	5,236	4,741	14,740	13,737
Net income	18,814	17,511	53,582	51,396
Total assets	5,198,878	4,770,672	5,198,878	4,770,672	$ 5,010,766
Expenditures for long-lived assets	797	645	2,768	2,320
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	28,515	27,036	83,684	79,656
Provision for loan losses	400	350	1,575	750
Net interest income after provision for loan losses	28,115	26,686	82,109	78,906
Noninterest income	8,607	5,174	20,753	15,947
Depreciation and amortization expense	642	654	1,985	1,928
Other noninterest expenses related to segments	16,255	15,599	48,676	46,574
Total noninterest expense	16,897	16,253	50,661	48,502
Income before income taxes	19,825	15,607	52,201	46,351
Income tax expense	4,347	3,344	11,371	9,834
Net income	15,478	12,263	40,830	36,517
Total assets	3,994,458	3,694,991	3,994,458	3,694,991
Expenditures for long-lived assets	662	612	2,259	1,864
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	(114)	(90)	(361)	(225)
Provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	(114)	(90)	(361)	(225)
Noninterest income	9,153	9,454	27,961	29,329
Depreciation and amortization expense	360	371	1,089	1,137
Other noninterest expenses related to segments	6,217	6,194	19,631	19,986
Total noninterest expense	6,577	6,565	20,720	21,123
Income before income taxes	2,462	2,799	6,880	7,981
Income tax expense	646	710	1,845	2,008
Net income	1,816	2,089	5,035	5,973
Total assets	78,812	69,494	78,812	69,494
Expenditures for long-lived assets	87	14	379	327
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)	4,577	6,503	18,097	18,981
Provision for loan losses	0	0	0	0
Net interest income after provision for loan losses	4,577	6,503	18,097	18,981
Noninterest income	582	587	1,748	1,675
Depreciation and amortization expense	40	44	118	129
Other noninterest expenses related to segments	3,356	3,200	10,486	9,726
Total noninterest expense	3,396	3,244	10,604	9,855
Income before income taxes	1,763	3,846	9,241	10,801
Income tax expense	243	687	1,524	1,895
Net income	1,520	3,159	7,717	8,906
Total assets	1,125,608	1,006,187	1,125,608	1,006,187
Expenditures for long-lived assets	$ 48	$ 19	$ 130	$ 129

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Changes in fair value of available for sale debt securities, before tax		$ 3,772	$ (5,924)	$ 25,985	$ (23,605)
Changes in fair value of available for sale debt securities, tax		886	(1,393)	6,106	(5,548)
Changes in fair value of available for sale debt securities		2,886	(4,531)	19,879	(18,057)
Net gains (losses) on debt securities reclassified into earnings, before tax	[1]	0	0	(80)	0
Net gains (losses) on debt securities reclassified into earnings, tax	[1]	0	0	(19)	0
Net gains (losses) on debt securities reclassified into earnings	[1]	0	0	(61)	0
Net change in fair value of available for sale debt securities, before tax		3,772	(5,924)	26,065	(23,605)
Net change in fair value of available for sale debt securities, tax		886	(1,393)	6,125	(5,548)
Net change in fair value of available for sale debt securities		2,886	(4,531)	19,940	(18,057)
Change in fair value of cash flow hedges, before tax		(283)	(626)	(1,653)	632
Change in fair value of cash flow hedges, tax		(66)	(148)	(388)	50
Change in fair value of cash flow hedges		(217)	(478)	(1,265)	582
Net cash flow hedge losses reclassified into earnings, before tax	[2]	60	830	39	1,082
Net cash flow hedge losses reclassified into earnings, tax	[2]	14	197	9	255
Net cash flow hedge losses reclassified into earnings	[2]	46	633	30	827
Net change in fair value of cash flow hedges, before tax		(223)	204	(1,614)	1,714
Net change in fair value of cash flow hedges, tax		(52)	49	(379)	305
Net change in fair value of cash flow hedges		(171)	155	(1,235)	1,409
Amortization of net actuarial losses, before tax	[3]	300	477	900	1,430
Amortization of net actuarial losses, tax	[3]	70	112	211	337
Amortization of net actuarial losses	[3]	230	365	689	1,093
Amortization of net prior service credits, before tax	[3]	(4)	(6)	(12)	(17)
Amortization of net prior service credits, tax	[3]	(1)	(2)	(3)	(5)
Amortization of net prior service credits	[3]	(3)	(4)	(9)	(12)
Net change in defined benefit plan obligations, before tax		296	471	888	1,413
Net change in defined benefit plan obligations, tax		69	110	208	332
Net change in defined benefit plan obligations		227	361	680	1,081
Total other comprehensive income (loss), before tax		3,845	(5,249)	25,339	(20,478)
Total other comprehensive income (loss), tax		903	(1,234)	5,954	(4,911)
Total other comprehensive income (loss), net of tax		$ 2,942	$ (4,015)	$ 19,385	$ (15,567)
[1]	The pre-tax amount is reported as net realized losses on securities in the Unaudited 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 Unaudited Consolidated Statements of Income.
[3]	The pre-tax amounts are included in other expenses in the Unaudited Consolidated Statements of Income.

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accumulated other comprehensive income (loss), beginning balance	$ (11,866)	$ (35,062)	$ (28,309)	$ (23,510)
Other comprehensive income (loss) before reclassifications	2,669	(5,009)	18,614	(17,475)
Amounts reclassed from accumulated other comprehensive income (loss)	273	994	771	1,908
Total other comprehensive income (loss), net of tax	2,942	(4,015)	19,385	(15,567)
Accumulated other comprehensive income (loss), ending balance	(8,924)	(39,077)	(8,924)	(39,077)
Net Unrealized Gains (Losses) on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance	292	(21,060)	(16,762)	(7,534)
Other comprehensive income (loss) before reclassifications	2,886	(4,531)	19,879	(18,057)
Amounts reclassed from accumulated other comprehensive income (loss)	0	0	61	0
Total other comprehensive income (loss), net of tax	2,886	(4,531)	19,940	(18,057)
Accumulated other comprehensive income (loss), ending balance	3,178	(25,591)	3,178	(25,591)
Net Unrealized Losses on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance	(873)	826	191	(428)
Other comprehensive income (loss) before reclassifications	(217)	(478)	(1,265)	582
Amounts reclassed from accumulated other comprehensive income (loss)	46	633	30	827
Total other comprehensive income (loss), net of tax	(171)	155	(1,235)	1,409
Accumulated other comprehensive income (loss), ending balance	(1,044)	981	(1,044)	981
Pension Benefit Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance	(11,285)	(14,828)	(11,738)	(15,548)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassed from accumulated other comprehensive income (loss)	227	361	680	1,081
Total other comprehensive income (loss), net of tax	227	361	680	1,081
Accumulated other comprehensive income (loss), ending balance	$ (11,058)	$ (14,467)	$ (11,058)	$ (14,467)

Earning Per Common Share (Calcu

Earning Per Common Share (Calculation of Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Net income	$ 18,814	$ 17,511	$ 53,582	$ 51,396
Less dividends and undistributed earnings allocated to participating securities	(36)	(36)	(105)	(112)
Net income applicable to common shareholders	$ 18,778	$ 17,475	$ 53,477	$ 51,284
Weighted average common shares outstanding - basic	17,338,000	17,283,000	17,324,000	17,263,000
Basic earnings per common share	$ 1.08	$ 1.01	$ 3.09	$ 2.97
Less dividends and undistributed earnings allocated to participating securities	$ (36)	$ (36)	$ (105)	$ (112)
Net income applicable to common shareholders	$ 18,778	$ 17,475	$ 53,477	$ 51,284
Dilutive effect of common stock equivalents	76,000	99,000	82,000	129,000
Weighted average common shares outstanding - diluted	17,414,000	17,382,000	17,406,000	17,392,000
Diluted earnings per common share	$ 1.08	$ 1.01	$ 3.07	$ 2.95
Antidilutive common stock equivalents	93,075	41,525	87,775	46,692

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended			12 Months Ended
		Sep. 30, 2019		Sep. 30, 2018	Sep. 30, 2019		Sep. 30, 2018	Dec. 31, 2018	Jan. 01, 2019
Operating lease right-of-use assets		$ 27,500			$ 27,500			$ 0	$ 28,900
Operating lease liabilities		$ 29,541	[1]		$ 29,541	[1]		$ 0	$ 30,900
Operating lease weighted average discount rate		3.66%			3.66%
Number of operating leases not yet commenced		1			1
Operating leases, weighted average lease term		14 years 1 month 6 days			14 years 1 month 6 days
Operating lease rent expense	[2]	$ 944		$ 942	$ 2,823		$ 2,800
Options to extend reasonably certain of being exercised					4,200
Short-term operating lease liabilities		$ 2,300			$ 2,300
Minimum [Member]
Lease expiration period					2 months			5 months
Operating lease renewal term		1 year			1 year
Lease expiration period, renewal option								1 year
Maximum [Member]
Lease expiration period					21 years			22 years
Operating lease renewal term		5 years			5 years
Lease expiration period, renewal option								5 years
[1]	Includes short-term operating lease liabilities of $2.3 million .
[2]	Included in net occupancy expenses in the Unaudited Consolidated Income Statement.

Leases (Schedule of Operating L

Leases (Schedule of Operating Lease Payments) (Details) - USD ($) $ in Thousands		Sep. 30, 2019		Jan. 01, 2019	Dec. 31, 2018
Leases [Abstract]
Operating lease minimum payments, Due Current Year		$ 930
Operating lease minimum payments, Due Year Two		3,515
Operating lease minimum payments, Due Year Three		3,312
Operating lease minimum payments, Due Year Four		3,165
Operating lease minimum payments, Due Year Five		3,090
Operating lease minimum payments, Due after Year Five		24,716
Total operating lease payments	[1]	38,728
Interest		9,187
Present value of operating lease liabilities		$ 29,541	[2]	$ 30,900	$ 0
[1]	Includes $4.2 million related to options to extend lease terms that are reasonably certain of being exercised.
[2]	Includes short-term operating lease liabilities of $2.3 million .

Leases (Lease Cost and Cash Pai

Leases (Lease Cost and Cash Paid) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Leases [Abstract]
Operating lease cost		$ 931		$ 2,787
Variable lease cost		13		36
Total lease cost	[1]	944	$ 942	2,823	$ 2,800
Cash paid reducing operating lease liabilities		$ 926		$ 2,677
[1]	Included in net occupancy expenses in the Unaudited Consolidated Income Statement.

Leases (Future Minimum Lease Pa

Leases (Future Minimum Lease Payments) (Details) $ in Thousands	Dec. 31, 2018USD ($)
Leases [Abstract]
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 minimum lease payments	$ 36,201

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Commitments to extend credit on standby letters of credit [Member] | Commitments to extend credit [Member]
Commitments and Contingencies Disclosure [Line Items]
Contract amount	$ 9,343	$ 7,706

Commitments and Contingencies_3

Commitments and Contingencies (Financial Instruments with Off Balance Sheet Risk) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 84,820	$ 30,766
Forward sale commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	156,594	61,993
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	729,913	648,050
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	729,913	648,050
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	73,040	46,510
Foreign exchange contracts [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	2,648	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 on commerical loans [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	481,350	533,884
Commitments to extend credit on home equity lines [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	290,442	270,462
Commitments to extend credit on other loans [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	74,931	46,698
Commitments to extend credit on standby letters of credit [Member] | Commitments to extend credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract amount	$ 9,343	$ 7,706