Washington Trust Bancorp (WASH) 10-K 6 Mar 17 2016 Q4 Annual report Financial data

DOCUMENT AND ENTITY INFORMATION

DOCUMENT AND ENTITY INFORMATION - USD ($)	12 Months Ended
	Dec. 31, 2016	Feb. 28, 2017	Jun. 30, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	Washington Trust Bancorp Inc
Entity Central Index Key	737,468
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q4
Amendment Flag	false
Entity Common Stock, Shares Outstanding		17,191,070
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 559,496,756

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Assets:
Cash and due from banks		$ 106,185	$ 93,222
Short-term investments		1,612	4,409
Mortgage loans held for sale (including $29,434 in 2016 and $33,969 in 2015 measured at fair value)		29,434	38,554
Securities:
Available for sale, at fair value		739,912	375,044
Held to maturity, at amortized cost (fair value $15,920 in 2016 and $20,516 in 2015)		15,633	20,023
Total securities		755,545	395,067
Federal Home Loan Bank stock, at cost		43,129	24,316
Loans:
Total loans	[1]	3,234,371	3,013,127
Less allowance for loan losses		26,004	27,069
Net loans		3,208,367	2,986,058
Premises and equipment, net		29,020	29,593
Investment in bank-owned life insurance		71,105	65,501
Goodwill		64,059	64,059
Identifiable intangible assets, net		10,175	11,460
Other assets		62,484	59,365
Total assets		4,381,115	3,771,604
Liabilities:
Demand deposits		585,960	537,298
NOW accounts		427,707	412,602
Money market accounts		730,075	823,490
Savings accounts		358,397	326,967
Time deposits		961,613	833,898
Total deposits		3,063,752	2,934,255
Federal Home Loan Bank advances		848,930	378,973
Junior subordinated debentures		22,681	22,681
Other liabilities		54,948	60,307
Total liabilities		3,990,311	3,396,216
Commitments and contingencies
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares at December 31, 2016 and 30,000,000 at December 31, 2015; issued and outstanding 17,170,820 shares at December 31, 2016 and 17,019,578 shares at December 31, 2015		1,073	1,064
Paid-in capital		115,123	110,949
Retained earnings		294,365	273,074
Accumulated other comprehensive loss		(19,757)	(9,699)
Total shareholders’ equity		390,804	375,388
Total liabilities and shareholders’ equity		4,381,115	3,771,604
Commercial [Member]
Loans:
Total loans		1,771,666	1,654,547
Residential Real Estate [Member]
Loans:
Total loans		1,122,748	1,013,555
Consumer [Member]
Loans:
Total loans		$ 339,957	$ 345,025
[1]	Includes net unamortized loan origination costs of $3.0 million and $2.6 million, respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand, respectively, at December 31, 2016 and 2015.

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Mortgage loans held for sale, fair value	$ 29,434	$ 33,969
Securities held to maturity, fair value	$ 15,920	$ 20,516
Common stock, par value (in dollars per share)	$ 0.0625	$ 0.0625
Common stock, shares authorized (in shares)	60,000,000	30,000,000
Common stock, shares issued (in shares)	17,170,820	17,019,578
Common stock, shares outstanding (in shares)	17,170,820	17,019,578

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest income:
Interest and fees on loans	$ 119,491	$ 114,229	$ 107,842
Taxable interest on securities	11,584	8,875	10,437
Nontaxable interest on securities	982	1,555	2,149
Dividends on corporate stock and Federal Home Loan Bank stock	1,091	953	561
Other interest income	322	138	128
Total interest and dividend income	133,470	125,750	121,117
Interest expense:
Deposits	12,504	13,142	12,937
Federal Home Loan Bank advances	9,992	7,746	7,698
Junior subordinated debentures	491	871	964
Other interest expense	5	9	13
Total interest expense	22,992	21,768	21,612
Net interest income	110,478	103,982	99,505
Provision for loan losses	5,650	1,050	1,850
Net interest income after provision for loan losses	104,828	102,932	97,655
Noninterest income:
Wealth management revenues	37,569	35,416	33,378
Merchant processing fees	0	0	1,291
Mortgage banking revenues	13,183	9,901	7,152
Service charges on deposit accounts	3,702	3,865	3,395
Card interchange fees	3,385	3,199	3,057
Income from bank-owned life insurance	2,659	1,982	1,846
Loan related derivative income	3,243	2,441	1,136
Equity in earnings (losses) of unconsolidated subsidiaries	(354)	(293)	(276)
Net gain on sale of business line	0	0	6,265
Other income	1,742	1,829	1,771
Total noninterest income	65,129	58,340	59,015
Noninterest expense:
Salaries and employee benefits	67,221	63,024	58,530
Net occupancy	7,151	7,000	6,312
Equipment	6,208	5,533	4,903
Merchant processing costs	0	0	1,050
Outsourced services	5,222	5,111	4,483
Legal, audit and professional fees	2,579	2,741	2,336
FDIC deposit insurance costs	1,878	1,846	1,762
Advertising and promotion	1,458	1,526	1,546
Amortization of intangibles	1,284	904	644
Debt prepayment penalties	431	0	6,294
Acquisition related expenses	0	989	0
Change in fair value of contingent consideration	(898)	41	0
Other expenses	8,569	8,214	8,987
Total noninterest expense	101,103	96,929	96,847
Income before income taxes	68,854	64,343	59,823
Income tax expense	22,373	20,878	18,999
Net income	$ 46,481	$ 43,465	$ 40,824
Weighted average common shares outstanding - basic	17,081	16,879	16,689
Weighted average common shares outstanding - diluted	17,208	17,067	16,872
Per share information:
Basic earnings per common share (in dollars per share)	$ 2.72	$ 2.57	$ 2.44
Diluted earnings per common share (in dollars per share)	2.70	2.54	2.41
Cash dividends declared per share (in dollars per share)	$ 1.46	$ 1.36	$ 1.22

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 46,481	$ 43,465	$ 40,824
Other comprehensive (loss) income, net of tax:
Net change in fair value of securities available for sale	(7,876)	(3,171)	1,021
Net change in fair value of cash flow hedges	(257)	244	331
Net change in defined benefit plan obligation adjustment	(1,925)	2,037	(8,608)
Total other comprehensive (loss) income, net of tax	(10,058)	(890)	(7,256)
Total comprehensive income	$ 36,423	$ 42,575	$ 33,568

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Common stock, shares outstanding, beginning balance at Dec. 31, 2013		16,614,000
Stockholders' equity, beginning balance at Dec. 31, 2013	$ 329,646	$ 1,038	$ 97,566	$ 232,595	$ (1,553)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	40,824			40,824
Total other comprehensive income (loss), net of tax	(7,256)				(7,256)
Cash dividends declared	(20,582)			(20,582)
Share-based compensation	1,880		1,880
Common stock issued for acquisition	0
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit, shares		132,000
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit	1,767	$ 9	1,758
Common stock, shares outstanding, ending balance at Dec. 31, 2014		16,746,000
Stockholders' equity, ending balance at Dec. 31, 2014	346,279	$ 1,047	101,204	252,837	(8,809)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	43,465			43,465
Total other comprehensive income (loss), net of tax	(890)				(890)
Cash dividends declared	(23,228)			(23,228)
Share-based compensation	2,074		2,074
Common stock issued for acquisition, shares		137,000
Common stock issued for acquisition	5,430	$ 8	5,422
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit, shares		137,000
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit	$ 2,258	$ 9	2,249
Common stock, shares outstanding, ending balance at Dec. 31, 2015	17,019,578	17,020,000
Stockholders' equity, ending balance at Dec. 31, 2015	$ 375,388	$ 1,064	110,949	273,074	(9,699)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,481			46,481
Total other comprehensive income (loss), net of tax	(10,058)				(10,058)
Cash dividends declared	(25,190)			(25,190)
Share-based compensation	2,190		2,190
Common stock issued for acquisition	0
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit, shares		151,000
Exercise of stock options, issuance of other compensation-related equity instruments and related tax benefit	$ 1,993	$ 9	1,984
Common stock, shares outstanding, ending balance at Dec. 31, 2016	17,170,820	17,171,000
Stockholders' equity, ending balance at Dec. 31, 2016	$ 390,804	$ 1,073	$ 115,123	$ 294,365	$ (19,757)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 46,481	$ 43,465	$ 40,824
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	5,650	1,050	1,850
Depreciation of premises and equipment	3,651	3,381	3,133
Net amortization of premium and discount	2,779	1,568	999
Amortization of intangibles	1,284	904	644
Share–based compensation	2,190	2,074	1,880
Deferred income tax expense	868	1,820	1,847
Income from bank-owned life insurance	(2,659)	(1,982)	(1,846)
Net gain on sale of business line	0	0	(6,265)
Net gains on loan sales and commissions on loans originated for others	(13,137)	(9,826)	(6,802)
Net gain on sale of portfolio loans	(135)	0	0
Equity in (earnings) losses of unconsolidated subsidiaries	354	293	276
Proceeds from sales of loans	551,788	477,616	257,244
Loans originated for sale	(532,950)	(462,663)	(285,938)
Change in fair value of contingent consideration	(898)	41	0
Decrease (increase) in other assets	630	(4,458)	(8,250)
(Decrease) increase in other liabilities	(7,163)	(1,717)	3,052
Net cash provided by operating activities	58,733	51,566	2,648
Cash flows from investing activities:
Purchases of mortgage-backed securities available for sale	(431,662)	(44,682)	(53,051)
Purchases of other investment securities available for sale	(121,679)	(88,784)	(31,208)
Proceeds from sale of other investment securities available for sale	0	0	547
Maturities and principal payments of mortgage-backed securities available for sale	65,673	50,083	76,703
Maturities and principal payments of other investment securities available for sale	108,256	60,085	43,012
Maturities and principal payments of mortgage-backed securities held to maturity	4,193	4,960	4,445
(Purchases) remittance of Federal Home Loan Bank stock	(18,813)	13,414	0
Net proceeds from the sale of business line	0	0	7,205
Net increase in loans	(112,966)	(152,306)	(389,649)
Proceeds from sale of portfolio loans	510	0	1,200
Purchases of loans	(113,562)	(3,085)	(8,119)
Proceeds from the sale of property acquired through foreclosure or repossession	731	1,580	1,769
Purchases of premises and equipment	(3,112)	(5,479)	(5,226)
Purchases of bank-owned life insurance	(5,000)	0	(5,000)
Proceeds from Life Insurance Policies	2,054	0	0
Cash used in business combination, net of cash acquired	0	(1,671)	0
Net cash used in investing activities	(625,377)	(165,885)	(357,372)
Cash flows from financing activities:
Net increase in deposits	129,497	179,437	249,497
Proceeds from Federal Home Loan Bank advances	1,428,750	495,500	602,499
Repayment of Federal Home Loan Bank advances	(958,793)	(522,824)	(484,284)
Proceeds from stock option exercises and issuance of other equity instruments	977	1,563	1,189
Tax benefit from stock option exercises and other equity instruments	1,016	694	578
Cash dividends paid	(24,637)	(22,770)	(19,722)
Net cash provided by financing activities	576,810	131,600	349,757
Net increase (decrease) in cash and cash equivalents	10,166	17,281	(4,967)
Cash and cash equivalents at beginning of year	97,631	80,350	85,317
Cash and cash equivalents at end of year	107,797	97,631	80,350
Noncash Investing and Financing Activities:
Loans charged off	7,012	2,305	1,949
Loans transferred to property acquired through foreclosure or repossession	1,075	1,206	1,961
In conjunction with the purchase acquisition detailed in Note 3 to the Consolidated Financial Statements, assets were acquired and liabilities were assumed as follows:
Common stock issued for acquisition	0	5,430	0
Fair value of assets acquired, net of cash acquired	0	14,315	0
Fair value of liabilities assumed	0	7,214	0
Supplemental Disclosures:
Interest payments	22,267	21,947	21,862
Income tax payments	$ 19,822	$ 20,213	$ 15,515

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation Washington Trust Bancorp, Inc. (the “Bancorp”) is a publicly-owned registered bank holding company that has elected to be a financial holding company. The Bancorp owns all of the outstanding common stock of The Washington Trust Company, of Westerly (the “Bank”), a Rhode Island chartered commercial bank founded in 1800. Through its subsidiaries, the Bancorp offers a complete product line of financial services including commercial, residential and consumer lending, retail and commercial deposit products, and wealth management services through its offices in Rhode Island, eastern Massachusetts and Connecticut. The consolidated financial statements include the accounts of the Bancorp and its subsidiaries (collectively, the “Corporation” or “Washington Trust”). All significant intercompany transactions have been eliminated. Certain previously reported amounts have been reclassified to conform to current year’s presentation. The accounting and reporting policies of the Corporation conform to GAAP and to general practices of the banking industry. In preparing the financial statements, management is required to make estimates and assumptions that affect the reported amounts of assets and liabilities as of the date of the balance sheet and revenues and expenses for the period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to change are the determination of the allowance for loan losses, the valuation of goodwill and identifiable intangible assets, the assessment of investment securities for impairment and accounting for defined benefit pension plans. Short-term Investments Short-term investments consist of highly liquid investments with a maturity date of three months or less when purchased and are considered to be cash equivalents. The Corporation’s short-term investments may be comprised of overnight federal funds sold, securities purchased under resale agreements, money market mutual funds and U.S. Treasury bills. Securities Investments in debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and carried at amortized cost. Management determines the appropriate classification of securities at the time of purchase. Investments not classified as held to maturity are classified as available for sale. Securities available for sale consist of debt securities that are available for sale to respond to changes in market interest rates, liquidity needs, changes in funding sources and other similar factors. These assets are specifically identified and are carried at fair value. Changes in fair value of available for sale securities, net of applicable income taxes, are reported as a separate component of shareholders’ equity. Washington Trust does not have a trading portfolio. Premiums and discounts are amortized and accreted over the term of the securities on a method that approximates the level yield method. The amortization and accretion is included in interest income on securities. Interest income is recognized when earned. Realized gains or losses from sales of securities are determined using the specific identification method. The fair values of securities may be based on either quoted market prices or third party pricing services. When the fair value of an investment security is less than its amortized cost basis, the Corporation assesses whether the decline in value is other-than-temporary. The Corporation considers whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for impairment, the severity and duration of the impairment, changes in the value subsequent to the reporting date, forecasted performance of the issuer, changes in the dividend or interest payment practices of the issuer, changes in the credit rating of the issuer or the specific security, and the general market condition in the geographic area or industry in which the issuer operates. In determining whether an other-than-temporary impairment has occurred for debt securities, the Corporation compares the present value of cash flows expected to be collected from the security with the amortized cost of the security. If the present value of expected cash flows is less than the amortized cost of the security, then the entire amortized cost of the security will not be recovered; that is, a credit loss exists, and an other-than-temporary impairment shall be considered to have occurred. The credit loss component of an other-than-temporary impairment write-down for debt securities is recorded in earnings while the remaining portion of the impairment loss is recognized, net of tax, in other comprehensive income provided that the Corporation does not intend to sell the underlying debt security and it is more-likely-than-not that the Corporation would not have to sell the debt security prior to recovery of the unrealized loss, which may be to maturity. If the Corporation intended to sell any securities with an unrealized loss or it is more-likely-than-not that the Corporation would be required to sell the investment securities, before recovery of their amortized cost basis, then the entire unrealized loss would be recorded in earnings. See Note 5 for further discussion on the Corporation’s investment securities portfolio. Federal Home Loan Bank Stock The Bank is a member of the Federal Home Loan Bank of Boston (“FHLBB”). The FHLBB is a cooperative that provides services, including funding in the form of advances, to its member banking institutions. As a requirement of membership, the Bank must own a minimum amount of FHLBB stock, calculated periodically based primarily on its level of borrowings from the FHLBB. No market exists for shares of the FHLBB and therefore, they are carried at par value. FHLBB stock may be redeemed at par value 5 years following termination of FHLBB membership, subject to limitations which may be imposed by the FHLBB or its regulator, the Federal Housing Finance Board, to maintain capital adequacy of the FHLBB. While the Corporation currently has no intentions to terminate its FHLBB membership, the ability to redeem its investment in FHLBB stock would be subject to the conditions imposed by the FHLBB. The Corporation monitors its investment to determine if impairment exists. Based on the capital adequacy and the liquidity position of the FHLBB, management believes there is no impairment related to the carrying amount of the Corporation’s FHLBB stock as of December 31, 2016 . Mortgage Banking Activities Mortgage Loans Held for Sale - Residential mortgage loans originated and intended for sale in the secondary market are classified as held for sale. The Corporation has elected the fair value option pursuant to Accounting Standards Codification (“ASC”) 825, “Financial Instruments” for certain closed loans intended for sale. ASC 825 allows for the irrevocable option to elect fair value accounting for the initial and subsequent measurement for certain financial assets and liabilities on a contract-by-contract basis that may otherwise not be required to be measured at fair value under other accounting standards. Washington Trust elected the fair value option for certain residential real estate mortgage loans held for sale pursuant to forward sale commitments in order to better match changes in fair values of the loans with changes in the fair value of the derivative forward loan sale contracts used to economically hedge them. Changes in the fair value of loans held for sale are recorded in earnings and are offset by changes in fair value relating to forward sale commitments and interest rate lock commitments. For residential mortgage loans intended for sale that are not accounted for under the fair value option, lower of cost or market (“LOCOM”) accounting is applied. Such loans are carried at lower of aggregate cost, net of unamortized deferred loan origination fees and costs, or fair value. Gains and losses on residential loan sales are recognized at the time of sale and included in mortgage banking revenues. Commissions received on mortgage loans brokered to various investors are recognized when received and included in mortgage banking revenues. Loan Servicing Rights - Rights to service mortgage loans for others are recognized as an asset, including rights acquired through both purchases and originations. Upon the sale of mortgage loans, a mortgage servicing asset is established, which represents the current estimated fair value based on the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, ancillary income, prepayment speeds, and default rates and losses. Capitalized loan servicing rights are included in other assets. Mortgage servicing rights are amortized as an offset to mortgage banking revenues over the period of estimated net servicing income. They are periodically evaluated for impairment based on their fair value. Impairment is measured on an aggregated basis by stratifying the rights based on homogeneous characteristics such as note rate and loan type. The fair value is estimated based on the present value of expected cash flows, incorporating assumptions for discount rate, prepayment speed and servicing cost. Any impairment is recognized through a valuation allowance and as a reduction to mortgage banking revenues. Loans Portfolio Loans - Loans held in the portfolio are stated at the principal amount outstanding, net of unamortized deferred loan origination fees and costs. Interest income is accrued on a level yield basis based on principal amounts outstanding. Deferred loan origination fees and costs are amortized as an adjustment to yield over the life of the related loans. Nonaccrual Loans - Loans, with the exception of certain well-secured loans that are in the process of collection, are placed on nonaccrual status and interest recognition is suspended when such loans are 90 days or more overdue with respect to principal and/or interest or sooner if considered appropriate by management. Well-secured loans are permitted to remain on accrual status provided that full collection of principal and interest is assured and the loan is in the process of collection. Loans are also placed on nonaccrual status when, in the opinion of management, full collection of principal and interest is doubtful. 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. Impaired Loans - Impaired loans are loans for which it is probable that the Corporation will not be able to collect all amounts due according to the contractual terms of the loan agreements and loans restructured in a troubled debt restructuring. Impairment is measured on a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or if the loan is collateral dependent, at the fair value. 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. Interest income on nonaccrual impaired loans is recognized as described above under the caption “Nonaccrual Loans.” Impaired accruing loans consist of those troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt. Troubled Debt Restructured Loans - Loans are considered to be troubled debt restructurings when the Corporation has granted concessions to a borrower due to the borrower’s financial condition that it otherwise would not have considered. These concessions may include modifications of the terms of the debt such as deferral of payments, extension of maturity, reduction of principal balance, reduction of the stated interest rate other than normal market rate adjustments, or a combination of these concessions. Debt may be bifurcated with separate terms for each tranche of the restructured debt. Restructuring of a loan in lieu of aggressively enforcing the collection of the loan may benefit the Corporation by increasing the ultimate probability of collection. Restructured loans are classified as accruing or non-accruing based on management’s assessment of the collectability of the loan. Loans which are already on nonaccrual status at the time of the restructuring generally remain on nonaccrual status for approximately 6 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. Allowance for Loan Losses The allowance for loan losses is management’s best estimate of the risk of loss inherent in the loan portfolio as of the balance sheet date. The allowance is increased by provisions charged to earnings and by recoveries of amounts previously charged off, and is reduced by charge-offs on loans. Loan charge-offs are recognized when management believes the collectability of the principal balance outstanding is unlikely. Full or partial charge-offs on collateral dependent impaired loans are generally recognized when the collateral is deemed to be insufficient to support the carrying value of the loan. The level of the allowance is based on management’s ongoing review of the growth and composition of the loan portfolio, historical loss experience, estimated loss emergence period (the period from the event that triggers the eventual default until the actual loss is recognized with a charge-off), current economic conditions, analysis of asset quality and credit quality levels and trends, the performance of individual loans in relation to contract terms and other pertinent factors. A methodology is used to systematically measure the amount of estimated loan loss exposure inherent in the loan portfolio for the purposes of establishing a sufficient allowance for loan losses. The methodology includes: (1) the identification of loss allocations for individual loans deemed to be impaired and (2) the application of loss allocation factors for non-impaired loans based on historical loss experience and estimated loss emergence period, with adjustments for various exposures that management believes are not adequately represented by historical loss experience. Loss allocations for loans deemed to be impaired are measured on a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or, if the loan is collateral dependent, at the fair value of the collateral. For collateral dependent loans for which repayment is dependent on the sale of the collateral, management adjusts the fair value for estimated costs to sell. For collateral dependent loans for which repayment is dependent on the operation of the collateral, such as accruing troubled debt restructured loans, estimated costs to sell are not incorporated into the measurement. Management may also adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of circumstances associated with the property. For loans that are collectively evaluated, loss allocation factors are derived by analyzing historical loss experience by loan segment over an established look-back period deemed to be relevant to the inherent risk of loss in the portfolios. Loans are segmented by loan type, collateral type, delinquency status and loan risk rating, where applicable. These loss allocation factors are adjusted to reflect the loss emergence period. These amounts are supplemented by certain qualitative risk factors reflecting management’s view of how losses may vary from those represented by historical loss rates. These qualitative risk factors include: 1) changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; 2) changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; 3) changes in the nature and volume of the portfolio and in the terms of loans; 4) changes in the experience, ability, and depth of lending management and other relevant staff; 5) changes in the volume and severity of past due loans, the volume of nonaccrual loans, and the volume and severity of adversely classified or rated loans; 6) changes in the quality of the institution’s loan review system; 7) changes in the value of underlying collateral for collateral dependent loans; 8) the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and 9) the effect of other external factors such as legal and regulatory requirements on the level of estimated credit losses in the institution’s existing portfolio. Because the methodology is based upon historical experience and trends, current economic data, as well as management’s judgment, factors may arise that result in different estimations. Adversely different conditions or assumptions could lead to increases in the allowance. In addition, various regulatory agencies periodically review the allowance for loan losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination. The allowance is an estimate, and ultimate losses may vary from management’s estimate. Changes in the estimate are recorded in the results of operations in the period in which they become known, along with provisions for estimated losses incurred during that period. Premises and Equipment Premises and equipment are stated at cost less accumulated depreciation. Depreciation for financial reporting purposes is calculated on the straight-line method over the estimated useful lives of assets. Expenditures for major additions and improvements are capitalized while the costs of current maintenance and repairs are charged to operating expenses. The estimated useful lives of premises and improvements range from 5 to 40 years. For furniture, fixtures and equipment, the estimated useful lives range from 3 to 20 years. Goodwill and Other Identifiable Intangible Assets The Corporation allocated the cost of an acquired entity to the assets acquired and liabilities assumed based on their estimated fair values at the date of acquisition. Other intangible assets identified in acquisitions primarily consist of wealth management advisory contracts. The value attributed to other intangible assets was based on the time period over which they are expected to generate economic benefits. The excess of the purchase price for acquisitions over the fair value of the net assets acquired, including other intangible assets, was recorded as goodwill. Goodwill is not amortized but is tested for impairment at the reporting unit level, defined as the segment level, at least annually in the fourth quarter or more frequently whenever events or circumstances occur that indicate that it is more-likely-than-not that an impairment loss has occurred. In assessing impairment, the Corporation has the option to perform a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of such events or circumstances, we determine it is not more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, then we would not be required to perform a two-step impairment test. The Corporation has not opted to perform this qualitative analysis. Goodwill is tested for impairment using the two-step quantitative impairment analysis described below. The first step (“Step 1”) of the quantitative impairment analysis requires a comparison of each reporting unit’s fair value to its carrying value to identify potential impairment. The second step (“Step 2”) of the analysis is necessary only if a reporting unit’s carrying amount exceeds its fair value. Step 2 is a more detailed analysis, which involves measuring the excess of the fair value of the reporting unit, as determined in Step 1, over the aggregate fair value of the individual assets, liabilities, and identifiable intangibles as if the reporting unit was being acquired in a business combination. Goodwill impairment exists when a reporting unit’s carrying value of goodwill exceeds its implied fair value. Significant judgment is applied when goodwill is assessed for impairment. This judgment includes, but may not be limited to, the selection of appropriate discount rates, the identification of relevant market comparables and the development of cash flow projections. The selection and weighting of the various fair value techniques may result in a higher or lower fair value. Judgment is applied in determining the weightings that are most representative of fair value. Other intangible assets with definite lives are tested for impairment whenever events or circumstances occur that indicate that the carrying amount may not be recoverable. If applicable, the Corporation tests each of the intangibles by comparing the carrying value of the intangible asset to the sum of undiscounted cash flows expected to be generated by the asset. If the carrying amount of the asset exceeded its undiscounted cash flows, then an impairment loss would be recognized for the amount by which the carrying amount exceeds its fair value. Impairment of Long - Lived Assets Other than Goodwill Long-lived assets are reviewed for impairment whenever events or changes in business circumstances indicate that the the carrying amount may not be fully recoverable. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal. Property Acquired through Foreclosure or Repossession Property acquired through foreclosure or repossession is carried at the lower of cost or fair value less estimated costs to sell. Fair value of such assets is determined based on independent appraisals and other relevant factors. Any write-down to fair value at the time of foreclosure or repossession is charged to the allowance for loan losses. A valuation allowance is maintained for declines in market value and for estimated selling expenses. Increases to the valuation allowance, expenses associated with ownership of these properties, and gains and losses from their sale are included in foreclosed property costs. Loans that are substantively repossessed include only those loans for which the Corporation has obtained control of the collateral, but has not completed legal foreclosure proceedings. Bank-Owned Life Insurance The investment in BOLI represents the cash surrender value of life insurance policies on the lives of certain employees who have provided positive consent allowing the Bank to be the beneficiary of such policies. Increases in the cash value of the policies, as well as insurance proceeds received, are recorded in noninterest income, and are not subject to income taxes. The financial strength of the insurance carrier is reviewed prior to the purchase of BOLI and annually thereafter. Investment in Real Estate Limited Partnership Washington Trust has a 99.9% ownership interest in two real estate limited partnerships that renovate, own and operate two low-income housing complexes. Washington Trust neither actively participates nor has a controlling interest in these limited partnerships and accounts for its investments under the equity method of accounting. The carrying value of the investments is recorded in other assets on the Consolidated Balance Sheet. Net losses generated by the partnership are recorded as a reduction to Washington Trust’s investment and as a reduction of noninterest income in the Consolidated Statements of Income. Tax credits generated by the partnership are recorded as a reduction in the income tax provision in the year they are allowed for tax reporting purposes. The results of operations of the real estate limited partnerships are periodically reviewed to determine if the partnership generates sufficient operating cash flow to fund its current obligations. In addition, the current value of the underlying properties is compared to the outstanding debt obligations. If it is determined that the investment is permanently impaired, the carrying value will be written down to the estimated realizable value. Transfers and Servicing of Assets and Extinguishments of Liabilities The accounting for transfers and servicing of financial assets and extinguishments of liabilities is based on consistent application of a financial components approach that focuses on control. This approach distinguishes transfers of financial assets that are sales from transfers that are secured borrowings. After a transfer of financial assets, the Corporation recognizes all financial and servicing assets it controls and liabilities it has incurred and derecognizes financial assets it no longer controls and liabilities that have been extinguished. This financial components approach focuses on the assets and liabilities that exist after the transfer. Many of these assets and liabilities are components of financial assets that existed prior to the transfer. If a transfer does not meet the criteria for a sale, the transfer is accounted for as a secured borrowing with a pledge of collateral. Fee Revenue Wealth management revenues include asset-based revenues (trust and investment advisory fees and mutual fund fees) that are primarily accrued as earned based upon a percentage of asset values under administration. Also included in wealth management revenues are transaction-based revenues (financial planning fees, commissions and other service fees), which are recognized as revenue to the extent that services have been completed. Fee revenue from deposit service charges is generally recognized when earned. Pension Costs Pension benefits are accounted for using the net periodic benefit cost method, which recognizes the compensation cost of an employee’s pension benefit over that employee’s approximate service period. Pension benefit costs and benefit obligations incorporate various actuarial and other assumptions, including discount rates, mortality, rates of return on plan assets and compensation increases. Washington Trust evaluates these assumptions on an annual basis and makes modifications to the assumptions based on current rates and trends when it is appropriate to so do. The effect of modifications to those assumptions is recorded in other comprehensive income (loss) and amortized to net periodic cost over future periods. Washington Trust believes that the assumptions utilized in recording its obligations under its plans are reasonable based on its experience and market conditions. The funded status of defined benefit pension plans, measured as the difference between the fair value of plan assets and the projected benefit obligation, is recognized in the Consolidated Balance Sheet. The changes in the funded status of the defined benefit plans, including actuarial gains and losses and prior service costs and credits, are recognized in comprehensive income in the year in which the changes occur. Share-Based Compensation Share-based compensation plans provide for awards of stock options and other equity incentives, including nonvested share units and nonvested performance share units. Compensation expense for awards is recognized over the service period based on the fair value at the date of grant. The Corporation estimates grant date fair value for stock options using the Black-Scholes option-pricing model. Awards of nonvested share units and nonvested performance share units are valued at the fair market value of the Bancorp’s common stock as of the award date. Nonvested performance share unit compensation expense is based on the most recent performance assumption available and is adjusted as assumptions change. If the goals are not met, no compensation cost will be recognized and any recognized compensation costs will be reversed. Excess tax benefits (expenses) related to stock option exercises and issuance of other compensation-related equity instruments are reflected on the Consolidated Statements of Cash Flows as financing activity. Income Taxes Income tax expense is determined based on the asset and liability method, whereby deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Corporation recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Corporation records interest related to unrecognized tax benefits in income tax expense. Penalties, if incurred, would be recognized as a component of income tax expense. Segment Reporting 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. The methodologies and organizational hierarchies that define the business segments are periodically reviewed and revised. Results may be restated, when necessary, to reflect changes in organizational structure or allocation methodology. Any changes in estimates and allocations that may affect the reported results of any business segment will not affect the consolidated financial position or results of operations of Washington Trust as a whole. Management uses certain methodologies to allocate income and expenses to the business lines. A funds transfer pricing 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. Certain indirect expenses are allocated to segments. These include support unit expenses such as technology, operations and other support functions. Earnings Per Share (“EPS”) The Corporation utilizes the two-class method earnings allocation formula to determine earnings per share of each class of stock according to dividends and participation rights in undistributed earnings. Share based payments that entitle holders to receive non-forfeitable dividends before vesting are considered participating securities and included in earnings allocation for computing basic earnings per sha

Recently Issued Accounting Pron

Recently Issued Accounting Pronouncements	12 Months Ended
	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements Revenue from Contracts with Customers - Topic 606 Accounting Standards Update No. 2014-09, “Revenue from Contracts with Customers” (“ASU 2014-09”), was issued in May 2014 and provides a revenue recognition framework for any entity that either enters into contracts with customers to transfer goods or services or enters into contracts for the transfer of non-financial assets unless those contracts are within the scope of other accounting standards. As issued, ASU 2014-09 was effective for annual periods beginning after December 15, 2016, including interim periods within that reporting period with early adoption not permitted. The standard permits the use of either the retrospective or cumulative effect transition method. In August 2015, Accounting Standards Update No. 2015-14, “Deferral of the Effective Date” (“ASU 2015-14”) was issued and delayed the effective date of ASU 2014-09 to annual and interim periods in fiscal years beginning after December 15, 2017. In 2016, Accounting Standards Update No. 2016-08, “Principal versus Agent Considerations” (“ASU 2016-08”), Accounting Standards Update No. 2016-10, “Identifying Performance Obligations and Licensing” (“ASU 2016-10”) and Accounting Standards Update No. 2016-12, “Narrow-Scope Improvements and Practical Expedients” (“ASU 2016-12”) were issued. These ASUs do not change the core principle for revenue recognition in Topic 606; instead, the amendments provide more detailed guidance in a few areas and additional implementation guidance and examples, which are expected to reduce the degree of judgment necessary to comply with Topic 606. The effective date and transition requirements for ASU 2016-08, ASU 2016-10 and ASU 2016-12 are the same as those provided by ASU 2015-14. Management has assembled a project team to address the changes pursuant to Topic 606. The project team has made an initial scope assessment and additional progress is expected to be made in the second quarter of 2017. The Corporation has not yet determined the impact this ASU will have on its consolidated financial statements. Financial Instruments - Topic 825 Accounting Standards Update No. 2016-01, “Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”), was issued in January 2016 and provides revised guidance related to the accounting for and reporting of financial instruments. Some of the main provisions include: requiring most equity securities to be reported at fair value with unrealized gains and losses reported in the income statement; requiring separate presentation of financial assets and liabilities by measurement category and form (i.e. securities or loans); clarifying that entities must assess valuation allowances on a deferred tax asset related to available for sale debt securities in combination with their other deferred tax assets; and eliminating the requirement to disclose the method and significant assumptions used to estimate fair value for financial instruments measured at amortized cost on the balance sheet. ASU 2016-01 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2017. Management has met to discuss the impact and will assemble a project team to assess the steps required for adoption. The Corporation has not yet determined the impact ASU 2016-01 will have on its consolidated financial statements. 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 will depend on its classification as a finance or operating lease. ASU 2016-02 requires a modified retrospective transition, with a number of practical expedients that entities may elect to apply. ASU 2016-02 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2018. Early adoption is permitted. Washington Trust expects to adopt the provisions of ASU 2016-02 effective January 1, 2019. Management has met to discuss the impact and will assemble a project team to assess steps required for adoption. The Corporation has not yet determined the impact ASU 2016-02 will have on its consolidated financial statements. Derivatives and Hedging - Topic 815 Accounting Standards Update No. 2016-05, “Effect of Derivative Contract Novations on Existing Hedge Accounting Relationships” (“ASU 2016-05”), was issued in March 2016. ASU 2016-05 clarifies that a change in the counterparty to a derivative instrument that has been designated as the hedging instrument does not, in and of itself, require de-designation of that hedging relationship provided that all other hedge accounting criteria continue to be met. ASU 2016-05 allows for either a prospective approach or modified retrospective approach for adoption. ASU 2016-05 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2016. ASU 2016-05 will not have a material impact on the Corporation’s consolidated financial statements. Accounting Standards Update No. 2016-06, “Contingent Put and Call Options in Debt Instruments” (“ASU 2016-06”), was issued in March 2016. ASU 2016-06 clarifies the requirements for assessing whether contingent call or put options that can accelerate the payment of principal on debt instruments are clearly and closely related to their debt hosts by providing a four-step decision sequence to assess whether the economic characteristics of the embedded call and put options are clearly and closely related to the economic characteristics of their debt hosts. ASU 2016-06 allows for a modified retrospective approach for adoption. ASU 2016-06 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2016. ASU 2016-06 will not have a material impact on the Corporation’s consolidated financial statements. Stock Compensation - Topic 718 Accounting Standards Update No. 2016-09, “Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”), was issued in March 2016. ASU 2016-09 includes multiple provisions intended to simplify several aspects of the accounting for share-based payment transactions, including income tax consequences and the classification of certain tax-related transactions on the statement of cash flows. ASU 2016-09 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2016. Early adoption was permitted in any interim or annual period. Provisions should be applied using the appropriate transition method as detailed by the provisions of ASU 2016-09. Management adopted the provisions of this ASU on January 1, 2017. For Washington Trust, the most significant provision of this ASU pertained to the accounting of excess tax benefits or tax deficiencies on share based award exercises and vestings. ASU 2016-09 requires that excess tax benefits or tax deficiencies be recognized as income tax benefit or expense in the Consolidated Statements of Income in the period that they occur. The ASU also requires that the excess tax benefits or tax deficiencies be reported as an operating activity in the Consolidated Statement of Cash Flows. In accordance with the ASU, management utilized the prospective approach in adopting this provision. It is difficult to predict the amount of excess tax benefit or tax deficiency that may occur upon the exercise or vesting of a share award. The average annual excess tax benefit that the Corporation recognized as additional paid in capital over the last three years was approximately $760 thousand . The remaining provisions of ASU 2016-09 will not have a material impact on the consolidated financial statements. 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 held at the reporting date 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. Early adoption is permitted, for annual periods and interim periods within those annual periods, beginning after December 15, 2018. Management has assembled a project team that meets regularly to evaluate the provisions of this ASU, identify additional data requirements necessary and determine an approach for implementation. The Corporation has not yet determined if it will early adopt ASU 2016-13 or the impact it will have on its consolidated financial statements. Statement of Cash Flows - Topic 230 Accounting Standards Update No. 2016-15, “Classification of Certain Cash Receipts and Cash Payments” (“ASU 2016-15”), was issued in August 2016. ASU 2016-15 provides classification guidance on certain cash receipts and cash payments, including, but not limited to, debt prepayment costs, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, proceeds from the settlement of bank-owned life insurance policies and distributions received from equity method investees. The adoption of ASU 2016-15 requires a retrospective transition method applied to each period presented. This ASU is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted. The adoption of ASU 2016-15 is not expected to have a material impact on the Corporation’s consolidated financial statements. Accounting Standards Update No. 2016-18, “Restricted Cash” (“ASU 2016-18”), was issued in November 2016. ASU 2016-18 requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash. Restricted cash should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. The adoption of ASU 2016-18 requires a retrospective transition method applied to each period presented. This ASU is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted. The adoption of ASU 2016-18 is not expected to have a material impact on the Corporation’s consolidated financial statements. Intangibles - Goodwill and Other - Topic 350 Accounting Standards Update No. 2017-04, “Simplifying the Test for Goodwill Impairment” (“ASU 2017-04”), was issued in January 2017 and eliminates Step 2 of the annual goodwill impairment test. Step 2 is a more detailed analysis, which involves measuring the excess of the fair value of the reporting unit, as determined in Step 1, over the aggregate fair value of the individual assets, liabilities, and identifiable intangibles as if the reporting unit was being acquired in a business combination. Under ASU 2017-04, an impairment charge would be recognized for the amount by which the carrying amount exceeded the reporting unit’s fair value under Step 1. ASU 2015-16 is effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2019 and the provisions should be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The adoption of ASU 2017-04 is not expected to have a material impact on the Corporation’s consolidated financial statements.

Acquisition

Acquisition	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Acquisition	Acquisition On August 1, 2015, Washington Trust completed the acquisition of Halsey Associates, Inc., a registered investment adviser firm located in New Haven, Connecticut. Halsey specializes in providing investment counseling services to high-net-worth families, corporations, foundations and endowment clients. The primary reason for the acquisition was to expand the geographic reach of Washington Trust’s wealth management business. The cost to acquire Halsey included $1.7 million in cash, $5.4 million in the form of 136,543 shares of Washington Trust Bancorp, Inc. common stock and a $2.9 million contingent consideration liability for the estimated present value of future earn-outs to be paid, based on the future revenue growth of the acquired business during the 5-year period following the acquisition. See Note 16 for additional disclosure on the contingent consideration liability. The following table presents the estimated fair value of identifiable assets acquired and liabilities assumed as of the date of acquisition, August 1, 2015: (Dollars in thousands) Fair Value Assets: Cash $10 Deferred tax assets 653 Goodwill 5,945 Identifiable intangible assets 7,515 Other assets 202 Total assets acquired $14,325 Liabilities: Contingent consideration liability $2,904 Deferred tax liabilities 2,803 Other liabilities 1,507 Total liabilities assumed $7,214 Net assets acquired $7,111

Cash and Due from Banks

Cash and Due from Banks	12 Months Ended
	Dec. 31, 2016
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 (“FRB”). Some or all of these reserve requirements may be satisfied with vault cash. Reserve balances amounted to $11.5 million and $10.5 million , respectively, at December 31, 2016 and 2015 and were included in cash and due from banks in the Consolidated Balance Sheets. As of December 31, 2016 and 2015 , cash and due from banks includes interest-bearing deposits in other banks of $60.3 million and $48.2 million , respectively.

Securities

Securities	12 Months Ended
	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Securities	Securities The following tables present the amortized cost, gross unrealized holding gains, gross unrealized holding losses, and fair value of securities by major security type and class of security: (Dollars in thousands) December 31, 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Securities Available for Sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $111,483 $7 ($3,050 ) $108,440 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 592,833 4,923 (9,671 ) 588,085 Obligations of states and political subdivisions 14,423 62 — 14,485 Individual name issuer trust preferred debt securities 29,851 — (3,115 ) 26,736 Corporate bonds 2,155 16 (5 ) 2,166 Total securities available for sale $750,745 $5,008 ($15,841 ) $739,912 Held to Maturity: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $15,633 $287 $— $15,920 Total securities held to maturity 15,633 287 — 15,920 Total securities $766,378 $5,295 ($15,841 ) $755,832 (Dollars in thousands) December 31, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Securities Available for Sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $77,330 $73 ($388 ) $77,015 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 228,908 6,398 (450 ) 234,856 Obligations of states and political subdivisions 35,353 727 — 36,080 Individual name issuer trust preferred debt securities 29,815 — (4,677 ) 25,138 Corporate bonds 1,970 5 (20 ) 1,955 Total securities available for sale $373,376 $7,203 ($5,535 ) $375,044 Held to Maturity: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $20,023 $493 $— $20,516 Total securities held to maturity 20,023 493 — 20,516 Total securities $393,399 $7,696 ($5,535 ) $395,560 At December 31, 2016 and 2015 , securities available for sale and held to maturity with a fair value of $736.2 million and $346.1 million , respectively, were pledged as collateral for FHLBB borrowings, potential borrowings with the FRB, certain public deposits and for other purposes. See Note 12 for additional discussion of FHLBB borrowings. The schedule of maturities of debt securities available for sale and held to maturity 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 Held to Maturity December 31, 2016 Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $75,499 $74,921 $2,605 $2,653 Due after one year to five years 254,974 252,489 7,157 7,288 Due after five years to ten years 239,622 236,175 4,414 4,495 Due after ten years 180,650 176,327 1,457 1,484 Total securities $750,745 $739,912 $15,633 $15,920 Included in the above table were debt securities with an amortized cost balance of $155.6 million and a fair value of $149.5 million at December 31, 2016 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 2 months to 20 years, with call features ranging from 1 month to 5 years. Other-Than-Temporary Impairment Assessment Washington Trust assesses whether the decline in fair value of investment securities is other-than-temporary on a regular basis. Unrealized losses on debt securities may occur from current market conditions, increases in interest rates since the time of purchase, a structural change in an investment, volatility of earnings of a specific issuer, or deterioration in credit quality of the issuer. Management evaluates impairments in value both qualitatively and quantitatively to assess whether they are other-than-temporary. The following tables summarize temporarily impaired securities, segregated by length of time the securities have been in a continuous unrealized loss position: (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2016 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government agencies and U.S. government-sponsored enterprises 10 $98,433 ($3,050 ) — $— $— 10 $98,433 ($3,050 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 35 407,073 (9,671 ) — — — 35 407,073 (9,671 ) Individual name issuer trust preferred debt securities — — — 10 26,736 (3,115 ) 10 26,736 (3,115 ) Corporate bonds 2 400 (5 ) — — — 2 400 (5 ) Total temporarily impaired securities 47 $505,906 ($12,726 ) 10 $26,736 ($3,115 ) 57 $532,642 ($15,841 ) (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2015 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government agencies and U.S. government-sponsored enterprises 4 $34,767 ($388 ) — $— $— 4 $34,767 ($388 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 9 61,764 (450 ) — — — 9 61,764 (450 ) Individual name issuer trust preferred debt securities — — — 10 25,138 (4,677 ) 10 25,138 (4,677 ) Corporate bonds 3 1,235 (20 ) — — — 3 1,235 (20 ) Total temporarily impaired securities 16 $97,766 ($858 ) 10 $25,138 ($4,677 ) 26 $122,904 ($5,535 ) Further deterioration in credit quality of the underlying issuers of the securities, further 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. U.S. Government Agency and U.S. Government-Sponsored Enterprise Securities, including Mortgage-Backed Securities The gross unrealized losses on these 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. Based on the assessment of these factors, 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 Washington Trust will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at December 31, 2016 . Trust Preferred Debt Securities of Individual Name Issuers Included in debt securities in an unrealized loss position at December 31, 2016 were 10 trust preferred security holdings issued by 7 individual companies in the banking sector. Management believes the unrealized loss position in these holdings was attributable to the general widening of spreads for this category of debt securities issued by financial services companies since the time these securities were purchased. Based on the information available through the filing date of this report, all individual name trust preferred debt securities held in our portfolio continue to accrue and make payments as expected with no payment deferrals or defaults on the part of the issuers. As of December 31, 2016 , individual name issuers trust preferred debt securities with an amortized cost of $10.9 million and unrealized losses of $1.3 million were rated below investment grade by Standard & Poors, Inc. (“S&P”). Management reviewed the collectability of these securities taking into consideration such factors as the financial condition of the issuers, reported regulatory capital ratios of the issuers, credit ratings, including ratings in effect as of the reporting period date as well as credit rating changes between the reporting period date and the filing date of this report, and other information. We noted no additional downgrades to below investment grade between December 31, 2016 and the filing date of this report. Based on these analyses, management concluded that it expects to recover the entire amortized cost basis of these securities. Furthermore, Washington Trust does not intend to sell these securities and it is not more-likely-than-not that Washington Trust will be required to sell these securities before recovery of their cost basis, which may be maturity. Therefore, management does not consider these investments to be other-than-temporarily impaired at December 31, 2016 .

Loans

Loans	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Loans	Loans The following is a summary of loans: (Dollars in thousands) December 31, 2016 December 31, 2015 Amount % Amount % Commercial: Mortgages (1) $1,074,186 33 % $931,953 31 % Construction & development (2) 121,371 4 122,297 4 Commercial & industrial (3) 576,109 18 600,297 20 Total commercial 1,771,666 55 1,654,547 55 Residential real estate: Mortgages 1,094,824 34 984,437 33 Homeowner construction 27,924 1 29,118 1 Total residential real estate 1,122,748 35 1,013,555 34 Consumer: Home equity lines 264,200 8 255,565 8 Home equity loans 37,272 1 46,649 2 Other (4) 38,485 1 42,811 1 Total consumer 339,957 10 345,025 11 Total loans (5) $3,234,371 100 % $3,013,127 100 % (1) Loans primarily secured by income producing property. (2) Loans for construction of commercial properties, loans to developers for construction of residential properties and loans for land development. (3) Loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (4) Loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $3.0 million and $2.6 million , respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand , respectively, at December 31, 2016 and 2015 . At December 31, 2016 and 2015 , there were $1.4 billion and $1.3 billion , respectively, of loans pledged as collateral to the FHLBB under a blanket pledge agreement and to the FRB for the discount window. See Note 12 for additional disclosure regarding borrowings. Concentrations of Credit Risk A significant portion of our loan portfolio is concentrated among borrowers in southern New England and a substantial portion of the portfolio is collateralized by real estate in this area. The ability of single family residential and consumer borrowers to honor their repayment commitments is generally dependent on the level of overall economic activity within the market area and real estate values. The ability of commercial borrowers to honor their repayment commitments is dependent on the general economy as well as the health of the real estate economic sector in the Corporation’s market area. 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. Interest previously accrued but not collected on such loans 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) December 31, 2016 2015 Commercial: Mortgages $7,811 $5,711 Construction & development — — Commercial & industrial 1,337 3,018 Residential real estate: Mortgages 11,736 10,666 Homeowner construction — — Consumer: Home equity lines — 528 Home equity loans 1,058 1,124 Other 116 — Total nonaccrual loans $22,058 $21,047 Accruing loans 90 days or more past due $— $— As of December 31, 2016 and 2015 , loans secured by one- to four-family residential property amounting to $5.7 million and $2.6 million , respectively, were in process of foreclosure. Nonaccrual loans of $3.5 million and $7.4 million , respectively, were current as to the payment of principal and interest as of December 31, 2016 and 2015 . There were no significant commitments to lend additional funds to borrowers whose loans were on nonaccrual status at December 31, 2016 . Interest income that would have been recognized had nonaccrual loans been current in accordance with their original terms was approximately $1.6 million , $1.5 million and $1.3 million in 2016 , 2015 and 2014 , respectively. Interest income included in the Consolidated Statements of Income on nonaccrual loans amounted to approximately $640 thousand , $522 thousand and $455 thousand , respectively, in 2016 , 2015 and 2014 . Past Due Loans Past due status is based on the contractual payment terms of the loan. The following tables present an aging analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due December 31, 2016 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Mortgages $901 $— $7,807 $8,708 $1,065,478 $1,074,186 Construction & development — — — — 121,371 121,371 Commercial & industrial 409 — 745 1,154 574,955 576,109 Residential real estate: Mortgages 5,381 652 6,193 12,226 1,082,598 1,094,824 Homeowner construction — — — — 27,924 27,924 Consumer: Home equity lines 655 26 — 681 263,519 264,200 Home equity loans 776 76 658 1,510 35,762 37,272 Other 32 1 110 143 38,342 38,485 Total loans $8,154 $755 $15,513 $24,422 $3,209,949 $3,234,371 (Dollars in thousands) Days Past Due December 31, 2015 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Mortgages $51 $— $4,504 $4,555 $927,398 $931,953 Construction & development — — — — 122,297 122,297 Commercial & industrial 405 9 48 462 599,835 600,297 Residential real estate: Mortgages 3,028 2,964 3,294 9,286 975,151 984,437 Homeowner construction — — — — 29,118 29,118 Consumer: Home equity lines 883 373 518 1,774 253,791 255,565 Home equity loans 748 490 222 1,460 45,189 46,649 Other 22 — — 22 42,789 42,811 Total loans $5,137 $3,836 $8,586 $17,559 $2,995,568 $3,013,127 Included in past due loans as of December 31, 2016 and 2015 , were nonaccrual loans of $18.6 million and $13.6 million , respectively. All loans 90 days or more past due at December 31, 2016 and 2015 were classified as nonaccrual. Impaired Loans Impaired loans are loans for which it is probable that the Corporation will not be able to collect all amounts due according to the contractual terms of the loan agreements and loans restructured in a troubled debt restructuring. The following is a summary of impaired loans: (Dollars in thousands) Recorded Investment (1) Unpaid Principal Related Allowance December 31, 2016 2015 2016 2015 2016 2015 No Related Allowance Recorded: Commercial: Mortgages $4,676 $4,292 $9,019 $5,101 $— $— Construction & development — — — — — — Commercial & industrial 6,458 1,849 6,550 1,869 — — Residential real estate: Mortgages 14,385 8,441 14,569 8,826 — — Homeowner construction — — — — — — Consumer: Home equity lines — 6 — 64 — — Home equity loans 1,137 530 1,177 539 — — Other 116 — 116 — — — Subtotal 26,772 15,118 31,431 16,399 — — With Related Allowance Recorded: Commercial: Mortgages 5,104 10,873 6,087 10,855 448 1,633 Construction & development — — — — — — Commercial & industrial 662 2,024 699 2,248 3 771 Residential real estate: Mortgages 1,285 2,895 1,310 2,941 151 156 Homeowner construction — — — — — — Consumer: Home equity lines — 522 — 522 — 2 Home equity loans — 679 — 783 — 21 Other 28 145 29 144 4 — Subtotal 7,079 17,138 8,125 17,493 606 2,583 Total impaired loans $33,851 $32,256 $39,556 $33,892 $606 $2,583 Total: Commercial $16,900 $19,038 $22,355 $20,073 $451 $2,404 Residential real estate 15,670 11,336 15,879 11,767 151 156 Consumer 1,281 1,882 1,322 2,052 4 23 Total impaired loans $33,851 $32,256 $39,556 $33,892 $606 $2,583 (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 impaired accruing loans (troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt), the recorded investment also includes accrued interest. The following table presents the average recorded investment balance of impaired loans and interest income recognized on impaired loans segregated by loan class: (Dollars in thousands) Average Recorded Investment Interest Income Recognized Years ended December 31, 2016 2015 2014 2016 2015 2014 Commercial: Mortgages $13,201 $14,847 $22,971 $239 $327 $658 Construction & development — — — — — — Commercial & industrial 3,540 3,415 2,499 99 130 126 Residential real estate: Mortgages 12,848 5,423 4,006 322 147 101 Homeowner construction — — — — — — Consumer: Home equity lines 354 228 97 10 1 2 Home equity loans 1,233 487 100 38 11 4 Other 147 210 119 11 10 8 Totals $31,323 $24,610 $29,792 $719 $626 $899 Troubled Debt Restructurings Loans are considered restructured in a troubled debt restructuring 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 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 collectibility of the loan. Loans which are already on nonaccrual status at the time of the restructuring generally remain on nonaccrual status for approximately 6 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. Troubled debt restructurings are classified as impaired loans. The Corporation identifies loss allocations for impaired loans on an individual loan basis. The recorded investment in troubled debt restructurings was $22.3 million and $18.5 million , respectively, at December 31, 2016 and 2015 . These amounts included insignificant balances of accrued interest. The allowance for loan losses included specific reserves for these troubled debt restructurings of $567 thousand and $1.8 million , respectively, at December 31, 2016 and 2015 . As of December 31, 2016 , there were no significant commitments to lend additional funds to borrowers whose loans were restructured. The following table presents loans modified as a troubled debt restructuring: (Dollars in thousands) Outstanding Recorded Investment (1) # of Loans Pre-Modifications Post-Modifications Years ended December 31, 2016 2015 2016 2015 2016 2015 Commercial: Mortgages 1 1 $776 $1,190 $776 $1,190 Construction & development — — — — — — Commercial & industrial 9 3 6,229 584 6,229 584 Residential real estate: Mortgages 3 3 4,386 619 4,386 619 Homeowner construction — — — — — — Consumer: Home equity lines — — — — — — Home equity loans — 1 — 70 — 70 Other — 1 — 35 — 35 Totals 13 9 $11,391 $2,498 $11,391 $2,498 (1) 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 following table provides information on how loans were modified as a troubled debt restructuring: (Dollars in thousands) Years ended December 31, 2016 2015 Below-market interest rate concession $— $335 Payment deferral 1,111 903 Maturity / amortization concession 683 70 Interest only payments 4,326 — Combination (1) 5,271 1,190 Total $11,391 $2,498 (1) Loans included in this classification were modified with a combination of any two of the concessions listed in this table. In 2016 and 2015 , payment defaults on troubled debt restructured loans modified within the previous 12 months occurred on 7 loans totaling $1.6 million and 2 loans totaling $290 thousand , respectively. 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. As of December 31, 2016 and 2015 , the weighted average risk rating of the Corporation’s commercial loan portfolio was 4.68 and 4.68 , respectively. 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 7 for additional information. A description of the commercial loan categories are 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 collectibility. A “doubtful” loan is placed on non-accrual 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. The criticized loan portfolio, which generally consists of commercial loans that are risk-rated special mention or worse, and other selected loans are reviewed by management on a quarterly basis, focusing on the current status and strategies to improve the credit. An annual loan review program is conducted by a third party to provide an independent evaluation of the creditworthiness of the commercial loan portfolio, the quality of the underwriting and credit risk management practices and the appropriateness of the risk rating classifications. This review is supplemented with selected targeted internal reviews of the commercial loan portfolio. The following table presents the commercial loan portfolio, segregated by category of credit quality indicator: (Dollars in thousands) Pass Special Mention Classified December 31, 2016 2015 2016 2015 2016 2015 Mortgages $1,065,358 $914,774 $776 $3,035 $8,052 $14,144 Construction & development 121,371 122,297 — — — — Commercial & industrial 559,416 577,036 8,938 12,012 7,755 11,249 Total commercial loans $1,746,145 $1,614,107 $9,714 $15,047 $15,807 $25,393 Residential and Consumer The residential and consumer portfolios are monitored on an ongoing basis by the Corporation using delinquency information and loan type as credit quality indicators. These credit quality indicators are assessed on an aggregate basis in these relatively homogeneous portfolios. For non-impaired loans, the Corporation assigns loss allocation factors to each respective loan type. See Note 7 for additional information. Various other techniques are utilized to monitor indicators of credit deterioration in the portfolios of residential real estate mortgages and home equity lines and loans. Among these techniques is the periodic tracking of loans with an updated 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 mortgage and home equity consumer credits. See Note 7 for additional information. The following table presents the residential and consumer loan portfolios, segregated by category of credit quality indicator: (Dollars in thousands) Current and Under 90 Days Past Due Over 90 Days Past Due December 31, 2016 2015 2016 2015 Residential real estate: Accruing mortgages $1,083,088 $973,771 $— $— Nonaccrual mortgages 5,543 7,372 6,193 3,294 Homeowner construction 27,924 29,118 — — Total residential loans $1,116,555 $1,010,261 $6,193 $3,294 Consumer: Home equity lines $264,200 $255,047 $— $518 Home equity loans 36,614 46,427 658 222 Other 38,375 42,811 110 — Total consumer loans $339,189 $344,285 $768 $740 Loan Servicing Activities The following table presents an analysis of loan servicing rights: (Dollars in thousands) Loan Servicing Rights Valuation Allowance Total Balance at December 31, 2013 $2,767 ($69 ) $2,698 Loan servicing rights capitalized 869 — 869 Amortization (647 ) — (647 ) Decrease in impairment reserve — 67 67 Balance at December 31, 2014 2,989 (2 ) 2,987 Loan servicing rights capitalized 1,406 — 1,406 Amortization (1,047 ) — (1,047 ) Decrease in impairment reserve — 1 1 Balance at December 31, 2015 3,348 (1 ) 3,347 Loan servicing rights capitalized 1,412 — 1,412 Amortization (1,267 ) — (1,267 ) Decrease in impairment reserve — 1 1 Balance at December 31, 2016 $3,493 $— $3,493 The following table presents estimated aggregate amortization expense related to loan servicing assets: (Dollars in thousands) Years ending December 31: 2017 $1,137 2018 767 2019 517 2020 349 2021 235 Thereafter 488 Total estimated amortization expense $3,493 Mortgage loans and other loans sold to others are serviced on a fee basis under various agreements. Loans serviced for others are not included in the Consolidated Balance Sheets. The following table presents the balance of loans serviced for others, by type of loan: (Dollars in thousands) December 31, 2016 2015 Residential mortgages $522,766 $458,629 Commercial loans 101,317 109,173 Total $624,083 $567,802

Allowance for Loan Losses

Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Allowance for Loan Losses	Allowance for Loan Losses The allowance for loan losses is management’s best estimate of inherent risk of loss 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. Prior to December 31, 2015, an unallocated allowance was maintained for measurement imprecision associated with impaired and nonaccrual loans. As a result of further enhancement and refinement of the allowance methodology to provide a more precise quantification of probable losses in the loan portfolio, management concluded that the potential risks anticipated by the unallocated allowance had been incorporated into the allocated component of the methodology, eliminating the need for the unallocated allowance in the fourth quarter of 2015. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2016 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Total Beginning Balance $9,140 $1,758 $8,202 $19,100 $5,460 $2,509 $27,069 Charge-offs (5,816 ) — (759 ) (6,575 ) (200 ) (237 ) (7,012 ) Recoveries 56 — 156 212 11 74 297 Provision 6,591 (563 ) (607 ) 5,421 (19 ) 248 5,650 Ending Balance $9,971 $1,195 $6,992 $18,158 $5,252 $2,594 $26,004 (1) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2015 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Unallocated Total Beginning Balance $8,202 $1,300 $7,987 $17,489 $5,430 $2,713 $2,391 $28,023 Charge-offs (809 ) — (671 ) (1,480 ) (207 ) (618 ) — (2,305 ) Recoveries 92 — 87 179 28 94 — 301 Provision 1,655 458 799 2,912 209 320 (2,391 ) 1,050 Ending Balance $9,140 $1,758 $8,202 $19,100 $5,460 $2,509 $— $27,069 (1) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2014 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Unallocated Total Beginning Balance $8,022 $383 $7,835 $16,240 $6,450 $2,511 $2,685 $27,886 Charge-offs (977 ) — (558 ) (1,535 ) (132 ) (282 ) — (1,949 ) Recoveries 24 — 86 110 51 75 — 236 Provision 1,133 917 624 2,674 (939 ) 409 (294 ) 1,850 Ending Balance $8,202 $1,300 $7,987 $17,489 $5,430 $2,713 $2,391 $28,023 (1) 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) December 31, 2016 December 31, 2015 Related Allowance Related Allowance Loans Loans Loans Individually Evaluated For Impairment: Commercial: Mortgages $9,776 $448 $15,141 $1,633 Construction & development — — — — Commercial & industrial 7,098 3 3,871 771 Residential Real Estate 15,661 151 11,333 156 Consumer 1,280 4 1,881 23 Subtotal 33,815 606 32,226 2,583 Loans Collectively Evaluated For Impairment: Commercial: Mortgages 1,064,410 9,523 916,812 7,507 Construction & development 121,371 1,195 122,297 1,758 Commercial & industrial 569,011 6,989 596,426 7,431 Residential Real Estate 1,107,087 5,101 1,002,222 5,304 Consumer 338,677 2,590 343,144 2,486 Subtotal 3,200,556 25,398 2,980,901 24,486 Total $3,234,371 $26,004 $3,013,127 $27,069

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment The following presents a summary of premises and equipment: (Dollars in thousands) December 31, 2016 2015 Land and improvements $6,020 $6,020 Premises and improvements 37,913 36,358 Furniture, fixtures and equipment 28,383 27,420 Total premises and equipment 72,316 69,798 Less accumulated depreciation 43,296 40,205 Total premises and equipment, net $29,020 $29,593 Depreciation of premises and equipment amounted to $3.7 million , $3.4 million and $3.1 million , respectively, for the years ended December 31, 2016 , 2015 , and 2014 .

Goodwill and Other Intangibles

Goodwill and Other Intangibles	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangibles	Goodwill and Other Intangibles The following table presents the carrying value of goodwill at the reporting unit (or business segment) level: (Dollars in thousands) December 31, 2016 December 31, 2015 Commercial Banking Segment $22,591 $22,591 Wealth Management Services Segment 41,468 41,468 Total $64,059 $64,059 The balance of goodwill in the Commercial Banking segment at December 31, 2016 represents goodwill that arose from the acquisition of First Financial Corp. in 2002. The balance of goodwill in the Wealth Management Services segment at December 31, 2016 represents goodwill of $35.5 million that arose from the 2005 acquisition of Weston Financial and goodwill of $5.9 million resulting from the 2015 acquisition of Halsey. Intangible assets consist of wealth management advisory contracts and non-compete agreements. The following table presents the components of intangible assets: (Dollars in thousands) December 31, 2016 December 31, 2015 Advisory Contracts Non-compete Agreements Advisory Contracts Non-compete Agreements Gross carrying amount $20,803 $369 $20,803 $369 Accumulated amortization 10,648 349 9,610 102 Net amount $10,155 $20 $11,193 $267 The balance of intangible assets at December 31, 2016 includes wealth management advisory contracts resulting from the Weston Financial acquisition in 2005, as well as wealth management advisory contracts and non-compete agreements resulting from the acquisition of Halsey in 2015. The wealth management advisory contracts resulting from the Weston Financial acquisition are being amortized over a 20 -year life using a declining balance method, based on expected attrition for the current customer base derived from historical runoff data. The wealth management advisory contracts and non-compete agreements resulting from the acquisition of Halsey are being amortized on a straight-line basis over a 15 -year and 18 -month life, respectively. Amortization expense for the years ended December 31, 2016 , 2015 , and 2014 , amounted to $1.3 million , $904 thousand and $644 thousand , respectively. The following table presents estimated annual amortization expense for intangible assets at December 31, 2016 : (Dollars in thousands) Advisory Contracts Non-compete Agreements Total Years ending December 31, 2017 $1,014 $20 $1,034 2018 979 — 979 2019 943 — 943 2020 914 — 914 2021 891 — 891 2022 and thereafter 5,414 — 5,414

Income Tax Expense

Income Tax Expense	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Tax Expense	Income Tax Expense The following table presents the components of income tax expense: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Current tax expense: Federal $19,444 $17,864 $16,286 State 2,061 1,194 866 Total current tax expense 21,505 19,058 17,152 Deferred tax expense (benefit): Federal 796 2,003 1,820 State 72 (183 ) 27 Total deferred tax expense 868 1,820 1,847 Total income tax expense $22,373 $20,878 $18,999 Total income tax expense varies from the amount determined by applying the Federal income tax rate to income before income taxes. The following table presents the reasons for the differences: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Tax expense at Federal statutory rate $24,099 $22,520 $20,938 (Decrease) increase in taxes resulting from: Tax-exempt income (1,599 ) (1,604 ) (1,540 ) Dividends received deduction (58 ) (57 ) (29 ) BOLI (930 ) (694 ) (646 ) Federal tax credits (364 ) (364 ) (364 ) Change in fair value of contingent consideration (314 ) — — Acquisition related expenses — 318 — State income tax expense, net of federal income tax benefit 1,387 658 581 Other 152 101 59 Total income tax expense $22,373 $20,878 $18,999 The following table presents the approximate tax effects of temporary differences that give rise to deferred tax assets and deferred tax liabilities: (Dollars in thousands) December 31, 2016 2015 Deferred tax assets: Allowance for loan losses $9,621 $10,015 Defined benefit pension obligations 3,804 3,447 Deferred compensation 3,991 3,181 Deferred loan origination fees 1,999 2,001 Stock based compensation 1,519 1,772 Net unrealized losses on securities available for sale 4,008 — Other 3,495 3,547 Deferred tax assets 28,437 23,963 Deferred tax liabilities: Net unrealized gains on securities available for sale — (617 ) Amortization of intangibles (3,765 ) (4,240 ) Deferred loan origination costs (5,156 ) (5,089 ) Loan servicing rights (1,293 ) (1,238 ) Other (1,419 ) (1,009 ) Deferred tax liabilities (11,633 ) (12,193 ) Net deferred tax asset $16,804 $11,770 The Corporation’s net deferred tax asset is included in other assets in the Consolidated Balance Sheets. Management has determined that a valuation allowance is not required for any of the deferred tax assets since it is more-likely-than-not that these assets will be realized primarily through future reversals of existing taxable temporary differences, carryback to taxable income in prior years or by offsetting projected future taxable income. The Corporation had no unrecognized tax benefits as of December 31, 2016 and 2015 . The Corporation files income tax returns in the U.S. federal jurisdiction and various state jurisdictions. The Corporation is no longer subject to U.S. federal and state income tax examinations by tax authorities for years before 2013 .

Time Certificates of Deposit

Time Certificates of Deposit	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Time Certificates of Deposit	Time Certificates of Deposit The following table presents scheduled maturities of time certificates of deposit: (Dollars in thousands) Scheduled Maturity Weighted Average Rate Years ending December 31: 2017 $409,292 0.73 % 2018 188,978 1.12 2019 216,245 1.54 2020 85,922 1.61 2021 60,752 1.77 2022 and thereafter 424 1.89 Balance at December 31, 2016 $961,613 1.13 % The following table presents the amount of time certificates of deposit in denominations of $100 thousand or more at December 31, 2016 , maturing during the periods indicated: (Dollars in thousands) January 1, 2017 to March 31, 2017 $82,626 April 1, 2017 to June 30, 2017 33,443 July 1, 2017 to December 31, 2017 35,301 January 1, 201 and beyond 126,372 Balance at December 31, 2016 $277,742 Time certificates of deposit in denominations of $250 thousand or more totaled $53.4 million and $45.1 million , respectively, at December 31, 2016 and 2015 .

Borrowings

Borrowings	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Borrowings	Borrowings Federal Home Loan Bank Advances Advances payable to FHLBB amounted to $848.9 million and $379.0 million , respectively, at December 31, 2016 and 2015 . The following table presents scheduled maturities and weighted average interest rates on FHLBB advances outstanding as of December 31, 2016 : (Dollars in thousands) Scheduled Maturity Weighted Average Rate 2017 $420,075 0.89 % 2018 98,134 1.36 2019 137,258 1.65 2020 72,033 1.95 2021 51,222 2.50 2022 and thereafter 70,208 3.81 Total $848,930 1.49 % As of December 31, 2016 and 2015 , the Bank had access to a $40.0 million unused line of credit with the FHLBB and also had remaining available borrowing capacity of $594.5 million and $644.8 million , respectively. The Bank pledges certain qualified investment securities and loans as collateral to the FHLBB. Advances payable to FHLBB include short-term advances with original maturity due dates of one year or less. The following table presents certain information concerning short-term FHLBB advances: (Dollars in thousands) As of and for the years ended December 31, 2016 2015 2014 Average amount outstanding during the period $275,533 $155,874 $70,693 Amount outstanding at end of period $352,500 $107,500 $200,000 Highest month end balance during period $367,500 $229,500 $200,000 Weighted-average interest rate at end of period 0.79 % 0.55 % 0.37 % Weighted-average interest rate during the period 0.73 % 0.38 % 0.35 % Junior Subordinated Debentures Junior subordinated debentures amounted to $22.7 million at December 31, 2016 and 2015 . The Bancorp sponsored the creation of WT Capital Trust I (“Trust I”) and WT Capital Trust II (“Trust II”), Delaware statutory trusts created for the sole purpose of issuing trust preferred securities and investing the proceeds in junior subordinated debentures of the Bancorp. The Bancorp is the owner of all of the common securities of the trusts. In accordance with GAAP, the trusts are treated as unconsolidated subsidiaries. The common stock investment in the statutory trusts is included in “Other Assets” in the Consolidated Balance Sheet. On August 29, 2005, Trust I issued $8.3 million of capital securities (“Trust I Capital Securities”) in a private placement of trust preferred securities. The Trust I Capital Securities mature in September 2035, are redeemable at the Bancorp’s option beginning after five years, and require quarterly distributions by Trust I to the holder of the Trust I Capital Securities, at a rate of 5.97% until September 15, 2010, and thereafter at a rate equal to the three-month LIBOR rate plus 1.45% . The Bancorp has guaranteed the Trust I Capital Securities and, to the extent not paid by Trust I, accrued and unpaid distributions on the Trust I Capital Securities, as well as the redemption price payable to the Trust I Capital Securities holders. The proceeds of the Trust I Capital Securities, along with proceeds from the issuance of common securities by Trust I to the Bancorp, were used to purchase $8.3 million of the Bancorp’s junior subordinated deferrable interest notes (the “Trust I Debentures”) and constitute the primary asset of Trust I. Like the Trust I Capital Securities, the Trust I Debentures bear interest at a rate of 5.97% until September 15, 2010, and thereafter at a rate equal to the three-month LIBOR rate plus 1.45% . The Trust I Debentures mature on September 15, 2035, but may be redeemed at par at the Bancorp’s option, subject to the approval of the applicable banking regulator to the extent required under applicable guidelines or policies, at any time on or after September 15, 2010, or upon the occurrence of certain special qualifying events. On August 29, 2005, Trust II issued $14.4 million of capital securities (“Trust II Capital Securities”) in a private placement of trust preferred securities. The Trust II Capital Securities mature in November 2035, are redeemable at the Bancorp’s option beginning after five years, and require quarterly distributions by Trust II to the holder of the Trust II Capital Securities, at a rate of 5.96% until November 23, 2010, and thereafter at a rate equal to the three-month LIBOR rate plus 1.45% . The Bancorp has guaranteed the Trust II Capital Securities and, to the extent not paid by Trust II, accrued and unpaid distributions on the Trust II Capital Securities, as well as the redemption price payable to the Trust II Capital Securities holders. The proceeds of the Trust II Capital Securities, along with proceeds from the issuance of common securities by Trust II to the Bancorp, were used to purchase $14.4 million of the Bancorp’s junior subordinated deferrable interest notes (the “Trust II Debentures”) and constitute the primary asset of Trust II. Like the Trust II Capital Securities, the Trust II Debentures bear interest at a rate of 5.96% until November 23, 2010, and thereafter at a rate equal to the three-month LIBOR rate plus 1.45% . The Trust II Debentures mature on November 23, 2035, but may be redeemed at par at the Bancorp’s option, subject to the approval of the applicable banking regulator to the extent required under applicable guidelines or policies, at any time on or after November 23, 2010, or upon the occurrence of certain special qualifying events.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Shareholders' Equity	Shareholders’ Equity 2006 Stock Repurchase Plan In December 2006, the Bancorp’s Board of Directors approved the 2006 Stock Repurchase Plan authorizing the repurchase of up to 400,000 shares, or approximately 3% , of the Corporation’s common stock in open market transactions. This authority may be exercised from time to time and in such amounts as market conditions warrant, and subject to regulatory considerations. The repurchased shares would be held as treasury stock to be used for general corporate purposes. As of December 31, 2016 , a cumulative total of 185,400 shares have been repurchased, all of which were repurchased in 2007 at a total cost of $4.8 million . Dividends The primary source of liquidity for the Bancorp is dividends received from the Bank. The Bancorp and the Bank are regulated enterprises and their abilities to pay dividends are subject to regulatory review and restriction. Certain regulatory and statutory restrictions exist regarding dividends, loans, and advances from the Bank to the Bancorp. Generally, the Bank has the ability to pay dividends to the Bancorp subject to minimum regulatory capital requirements. The FDIC and the FRB have the authority to use their enforcement powers to prohibit a bank or bank holding company, respectively, from paying dividends if, in their opinion, the payment of dividends would constitute an unsafe or unsound practice. Under the most restrictive of these requirements, the Bank could have declared aggregate additional dividends of $195.4 million as of December 31, 2016 . Dividend Reinvestment Under the Amended and Restated Dividend Reinvestment and Stock Purchase Plan, 607,500 shares of the Corporation’s common stock were originally reserved to be issued for dividends reinvested and cash payments to the plan. Reserved Shares As of December 31, 2016 , a total of 2,071,309 common stock shares were reserved for issuance under the 2003 Plan, 2013 Plan and the Amended and Restated Dividend Reinvestment and Stock Purchase Plan. Regulatory Capital Requirements The Bancorp and the Bank are subject to various regulatory capital requirements administered by the FRB and the FDIC, respectively. Regulatory authorities can initiate certain mandatory actions if Bancorp or the Bank fail to meet minimum capital requirements, which could have a direct material effect on the Corporation’s financial statements. Capital adequacy guidelines and, additionally for banks, prompt corrective action regulations involve quantitative measures of assets, liabilities, and certain off-balance sheet items calculated under regulatory accounting practices. These quantitative measures, to ensure capital adequacy, require minimum amounts and ratios. Capital levels at December 31, 2016 exceeded the regulatory minimum levels to be considered “well capitalized.” The following table presents the Corporation’s and the Bank’s actual capital amounts and ratios, as well as the corresponding minimum and well capitalized regulatory amounts and ratios that were in effect during the respective periods: (Dollars in thousands) Actual For Capital Adequacy Purposes To Be “Well Capitalized” Under Prompt Corrective Action Regulations Amount Ratio Amount Ratio Amount Ratio December 31, 2016 Total Capital (to Risk-Weighted Assets): Corporation $390,867 12.26 % $255,093 8.00 % N/A N/A Bank 389,840 12.23 255,050 8.00 318,813 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 364,655 11.44 191,320 6.00 N/A N/A Bank 363,628 11.41 191,288 6.00 255,050 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 342,656 10.75 143,490 4.50 N/A N/A Bank 363,628 11.41 143,466 4.50 207,228 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 364,655 8.67 168,271 4.00 N/A N/A Bank 363,628 8.65 168,207 4.00 210,259 5.00 December 31, 2015 Total Capital (to Risk-Weighted Assets): Corporation 367,443 12.58 233,739 8.00 N/A N/A Bank 366,676 12.55 233,676 8.00 292,095 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 340,130 11.64 175,304 6.00 N/A N/A Bank 339,363 11.62 175,257 6.00 233,676 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 318,131 10.89 131,478 4.50 N/A N/A Bank 339,363 11.62 131,443 4.50 189,861 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 340,130 9.37 145,191 4.00 N/A N/A Bank 339,363 9.36 145,103 4.00 181,378 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 0.625% on January 1, 2016 and will increase by 0.625% each year until it reaches 2.5% on January 1, 2019.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2016
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 v alue of derivatives depends on the intended use of the derivative and resulting designation. Interest Rate Risk Management Agreements Interest rate swaps and caps 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 represent options purchased by the Corporation to manage the interest rate paid throughout the term of the option contract. The credit risk associated with these transactions is the risk of default by the counterparty. To minimize this risk, the Corporation enters into interest rate agreements only with highly rated counterparties that management believes to be creditworthy. The notional amounts of these agreements do not represent amounts exchanged by the parties and, thus, are not a measure of the potential loss exposure. Cash Flow Hedging Instruments As of December 31, 2016 and 2015 , the Bancorp had 2 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. In the fourth quarter of 2015 , the Bancorp entered into the interest rate cap contracts and paid a premium totaling $257 thousand to obtain the right to receive the difference between 3-month LIBOR and a 4.5% strike for both of the interest rate caps. The caps mature in 2020. Prior to December 31, 2015 , the Bancorp had 2 interest rate swap contracts designated as cash flow hedges to hedge the interest rate risk associated with the junior subordinated debentures noted above. During 2015 , both interest rate swaps contracts matured. During 2016 , the Bank executed 2 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. The effective portion of the changes in fair value of derivatives designated as cash flow hedges is recorded in other comprehensive income and subsequently reclassified to earnings when gains or losses are realized. The ineffective portion of changes in fair value of the derivatives is recognized directly in earnings as interest expense. 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 allows them to convert floating-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 floating-rate loan payments. We retain the risk that is associated with the potential failure of counterparties and the risk inherent in originating loans. As of December 31, 2016 and 2015 , Washington Trust had interest rate swap contracts with commercial loan borrowers with notional amounts of $428.7 million and $302.1 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 participating in commercial loan arrangements. Participating banks guarantee the performance on borrower-related interest rate swap contracts. These derivatives are not designated as hedges and therefore, changes in fair value are recognized in earnings. Under a risk participation-out agreement, a derivative asset, the Corporation participates out a portion of the credit risk associated with the interest rate swap position executed with the commercial borrower, for a fee paid to the participating bank. Under a risk participation-in agreement, a derivative liability, the Corporation assumes, or participates in, a portion of the credit risk associated with the interest rate swap position with the commercial borrower, for a fee received from the other bank. As of December 31, 2016 , the notional amounts of the risk participation-out agreements and risk participation-in agreements were $38.3 million and $28.5 million , respectively, compared to $25.3 million and $21.5 million , respectively, as of December 31, 2015 . Loan Commitments Interest rate lock commitments are extended to borrowers and relate to the origination of residential real estate mortgage loans held for sale. To mitigate the interest rate risk inherent in these rate locks, as well as closed residential real estate mortgage loans held for sale, forward commitments are established to sell individual residential real estate mortgage loans. Both interest rate lock commitments and commitments to sell residential real estate mortgage loans are derivative financial instruments, but do not meet criteria for hedge accounting and, as such the changes in fair value of these commitments are reflected in earnings. The Corporation has elected to carry certain closed residential real estate mortgage loans held for sale at fair value, as changes in fair value in these loans held for sale generally offset changes in interest rate lock and forward sale commitments. The following table presents the fair values of derivative instruments in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value December 31, Balance Sheet Location 2016 2015 Balance Sheet Location 2016 2015 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate swaps Other assets $— $— Other liabilities $378 $— Interest rate caps Other assets 134 187 Other liabilities — — Derivatives not Designated as Hedging Instruments: Forward loan commitments: Interest rate lock commitments Other assets 1,133 1,220 Other liabilities 88 — Commitments to sell mortgage loans Other assets 279 — Other liabilities 1,349 2,012 Loan related derivative contracts: Interest rate swaps with customers Other assets 2,036 8,027 Other liabilities — — Mirror swaps with counterparties Other assets — — Other liabilities 2,228 8,266 Risk participation agreements Other assets — 56 Other liabilities — 69 Total $3,582 $9,490 $4,043 $10,347 The following tables present the effect of derivative instruments in the Corporations’ Consolidated Statements of Income and Changes in Shareholders’ Equity: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax (Effective Portion) Location of Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) Gain (Loss) Recognized in Income (Ineffective Portion) Years ended December 31, 2016 2015 2014 2016 2015 2014 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate swaps ($224 ) $288 $331 Interest Expense $— $— $— Interest rate caps (33 ) (44 ) — Interest Expense — — — Total ($257 ) $244 $331 $— $— $— (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivative Years ended December 31, Statement of Income Location 2016 2015 2014 Derivatives not Designated as Hedging Instruments: Forward loan commitments: Interest rate lock commitments Mortgage banking revenues ($175 ) $28 $800 Commitments to sell mortgage loans Mortgage banking revenues 942 3 (1,442 ) Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income (598 ) 7,569 4,989 Mirror swaps with counterparties Loan related derivative income 3,854 (4,904 ) (3,853 ) Risk participation agreements Loan related derivative income (13 ) (224 ) — Total $4,010 $2,472 $494

Balance Sheet Offsetting

Balance Sheet Offsetting	12 Months Ended
	Dec. 31, 2016
Balance Sheet Offsetting [Abstract]
Balance Sheet Offsetting	Balance Sheet Offsetting For interest rate risk management contracts and loan-related derivative contracts, the Corporation records derivative assets and derivative liabilities on a net basis. The interest rate risk management contracts and loan-related derivative contracts with counterparties are subject to master netting agreements. The following tables present the Corporation’s derivative asset and derivative liability positions and the effect of netting arrangements on the Consolidated Balance Sheets: (Dollars in thousands) Gross Derivative Positions Offsetting Derivative Positions Net Amounts Presented in Balance Sheet Cash Collateral Pledged Net Amount December 31, 2016 Derivative Assets: Interest rate risk management contracts: Interest rate caps $134 $— $134 $— $134 Loan-related derivative contracts: Interest rate swaps with customers 4,920 2,884 2,036 — 2,036 Mirror swaps with counterparties 2,758 2,758 — — — Total $7,812 $5,642 $2,170 $— $2,170 Derivative Liabilities: Interest rate risk management contracts: Interest rate swaps $378 $— $378 $133 $245 Loan-related derivative contracts: Interest rate swaps with customers 2,884 2,884 — — — Mirror swaps with counterparties 4,986 2,758 2,228 1,295 933 Total $8,248 $5,642 $2,606 $1,428 $1,178 (Dollars in thousands) Gross Derivative Positions Offsetting Derivative Positions Net Amounts Presented in Balance Sheet Cash Collateral Pledged Net Amount December 31, 2015 Derivative Assets: Interest rate risk management contracts: Interest rate caps $187 $— $187 $— $187 Loan-related derivative contracts: Interest rate swaps with customers 8,027 — 8,027 — 8,027 Mirror swaps with counterparties — — — — — Total $8,214 $— $8,214 $— $8,214 Derivative Liabilities: Loan-related derivative contracts: Interest rate swaps with customers $— $— $— $— $— Mirror swaps with counterparties 8,266 — 8,266 8,343 (77 ) Total $8,266 $— $8,266 $8,343 ($77 ) As of December 31, 2016 and 2015 , Washington Trust pledged collateral to derivative counterparties in the form of cash totaling $1.4 million and $8.3 million , respectively. Washington Trust may need to post additional collateral in the future in proportion to potential increases in unrealized loss positions.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Corporation uses fair value measurements to record fair value adjustments to certain assets and liabilities and to determine fair value disclosures. As of December 31, 2016 and 2015 , securities available for sale, certain residential real estate mortgage loans held for sale, derivatives and the contingent consideration liability are recorded at fair value on a recurring basis. 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, certain residential real estate mortgage loans held for sale 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 certain residential real estate mortgage loans held for sale to better match changes in fair value of the loans with changes in the fair value of the derivative loan sale contracts used to economically hedge them. The aggregate principal amount of the residential real estate mortgage loans held for sale recorded at fair value was $29.4 million and $33.2 million , respectively, at December 31, 2016 and 2015 . The aggregate fair value of these loans as of the same dates was $29.4 million and $34.0 million , respectively. As of December 31, 2016 and 2015 , the aggregate fair value of residential real estate mortgage loans held for sale exceeded the aggregate principal amount by $40 thousand and $731 thousand , respectively. There were no residential real estate mortgage loans held for sale 90 days or more past due as of December 31, 2016 and 2015 . The following table presents the changes in fair value related to mortgage loans held for sale, interest rate lock commitments and commitments to sell residential real estate mortgage loans, for which the fair value option was elected. Changes in fair values are reported as a component of mortgage banking revenues in the Consolidated Statements of Income. (Dollars in thousands) Years ended December 31, 2016 2015 2014 Mortgage loans held for sale ($691 ) ($48 ) $598 Interest rate lock commitments (175 ) 28 800 Commitments to sell 942 3 (1,442 ) Total changes in fair value $76 ($17 ) ($44 ) Valuation Techniques Securities Securities available for sale are recorded at fair value on a recurring basis. When available, the Corporation uses quoted market prices to determine the fair value of securities; such items are classified as Level 1. There were no Level 1 securities held at December 31, 2016 and 2015 . Level 2 securities include debt securities with quoted prices, which 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 agencies and 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. Securities not actively traded whose fair value is determined through the use of cash flows utilizing inputs that are unobservable are classified as Level 3. There were no Level 3 securities held at December 31, 2016 and 2015 . 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. Loan Servicing Rights Loans sold with the retention of servicing result in the recognition of loan servicing rights. Loan servicing rights are included in other assets in the Consolidated Balance Sheets and are amortized as an offset to mortgage banking revenues over the estimated period of servicing. Loan servicing rights are evaluated quarterly for impairment based on their fair value. Impairment exists if the carrying value exceeds the estimated fair value. Impairment is measured on an aggregated basis by stratifying the loan servicing rights based on homogeneous characteristics such as note rate and loan type. The fair value is estimated using an independent valuation model that estimates the present value of expected cash flows, incorporating assumptions for discount rates and prepayment rates. Any impairment is recognized through a valuation allowance and as a reduction to mortgage banking revenues. Loan servicing rights are categorized as Level 3. Property Acquired Through Foreclosure or Repossession Property acquired through foreclosure or repossession included in other assets in the Consolidated Balance Sheets is adjusted to fair value less costs to sell upon transfer out of loans through a charge to allowance for loan losses. Subsequently, it is carried at the lower of carrying value or fair value less costs to sell. Such subsequent valuation charges are charged through earnings. Fair value is generally based upon appraised values of the collateral. Management may adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of the property, and such property is categorized as Level 3. Derivatives Interest rate swap and cap 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, Washington Trust considers factors such as the likelihood of default by the Corporation and its counterparties, its net exposures and remaining contractual life, among other factors, 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. Although the Corporation has determined that the majority of the inputs used to value its interest rate swap and cap contracts fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with interest rate contracts and risk participation agreements utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by the Corporation and its counterparties. However, as of December 31, 2016 and December 31, 2015 , 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 commitments to sell residential real estate mortgages) are estimated based on current market prices for similar assets in the secondary market and therefore are classified as Level 2 assets. Contingent Consideration Liability A contingent consideration liability was recognized upon the completion of the Halsey Associates, Inc. acquisition on August 1, 2015 and represents the estimated present value of future earn-outs to be paid based on the future revenue growth of the acquired business during the 5 -year period following the acquisition. The fair value measurement is based upon unobservable inputs, therefore, the contingent liability is classified within Level 3 of the fair value hierarchy. The unobservable inputs include probability estimates regarding the likelihood of achieving revenue growth targets and the discount rates utilized the discounted cash flow calculations applied to the estimates earn-outs to be paid. The discount rates used ranged from 3% to 4% . The contingent consideration liability is 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 are included in noninterest expenses in the Consolidated Statements of Income. The fair value of the contingency represents the estimated price to transfer the liability between market participants at the measurement date under current market conditions. Items Recorded at Fair Value on a Recurring Basis The following tables present the balances of assets and liabilities reported at fair value on a recurring basis: (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2016 Assets: Securities available for sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $108,440 $— $108,440 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 588,085 — 588,085 — Obligations of states and political subdivisions 14,485 — 14,485 — Individual name issuer trust preferred debt securities 26,736 — 26,736 — Corporate bonds 2,166 — 2,166 — Mortgage loans held for sale 29,434 — 29,434 — Derivative assets 3,582 — 3,582 — Total assets at fair value on a recurring basis $772,928 $— $772,928 $— Liabilities: Derivative liabilities $4,043 $— $4,043 $— Contingent consideration liability (1) 2,047 — — 2,047 Total liabilities at fair value on a recurring basis $6,090 $— $4,043 $2,047 (1) The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets. (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2015 Assets: Securities available for sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $77,015 $— $77,015 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 234,856 — 234,856 — Obligations of states and political subdivisions 36,080 — 36,080 — Individual name issuer trust preferred debt securities 25,138 — 25,138 — Corporate bonds 1,955 — 1,955 — Mortgage loans held for sale 33,969 — 33,969 — Derivative assets 9,490 — 9,490 — Total assets at fair value on a recurring basis $418,503 $— $418,503 $— Liabilities: Derivative liabilities $10,347 $— $10,347 $— Contingent consideration liability (1) 2,945 — — 2,945 Total liabilities at fair value on a recurring basis $13,292 $— $10,347 $2,945 (1) The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets. It is the Corporation’s policy to review and reflect transfers between Levels as of the financial statement reporting date. There were no transfers in and/or out of Level 1, 2 or 3 during the years ended December 31, 2016 and 2015 . The following table presents the change in the contingent consideration liability, a Level 3 liability measured at fair value on a recurring basis: (Dollars in thousands) Years ended December 31, 2016 2015 Beginning Balance $2,945 $— Initial recognition — 2,904 Change in fair value (898 ) 41 Payments — — Ending Balance $2,047 $2,945 Items Recorded at Fair Value on a Nonrecurring Basis The following table presents the carrying value of assets held at December 31, 2016 , which were written down to fair value during the year ended December 31, 2016 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $3,828 $— $— $3,828 Property acquired through foreclosure or repossession 605 — — 605 Total assets at fair value on a nonrecurring basis $4,433 $— $— $4,433 The allowance for loan losses on the collateral dependent impaired loans amounted to $469 thousand at December 31, 2016 . The following table summarizes the carrying value of assets held at December 31, 2015 , which were written down to fair value during the year ended December 31, 2015 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $10,545 $— $— $10,545 Property acquired through foreclosure or repossession 270 — — 270 Total assets at fair value on a nonrecurring basis $10,815 $— $— $10,815 The allowance for loan losses on the collateral dependent impaired loans amounted to $2.4 million at December 31, 2015 . The following tables present valuation techniques and unobservable inputs for assets measured at fair value on a nonrecurring basis for which the Corporation has utilized Level 3 inputs to determine fair value: (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2016 Collateral dependent impaired loans $3,828 Appraisals of collateral Discount for costs to sell 10% - 20% (15%) Appraisal adjustments (1) 0% - 10% (9%) Property acquired through foreclosure or repossession 605 Appraisals of collateral Discount for costs to sell 10% - 12% (11%) Appraisal adjustments (1) 6% - 50% (24%) (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, 2015 Collateral dependent impaired loans $10,545 Appraisals of collateral Discount for costs to sell 0% - 20% (2%) Property acquired through foreclosure or repossession 270 Appraisals of collateral Discount for costs to sell 12% Appraisal adjustments (1) 32% (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property. Valuation of Other Financial Instruments The methodologies for estimating the fair value of financial instruments that are measured at fair value on a recurring or nonrecurring basis are discussed above. The methodologies for other financial instruments are discussed below. Loans Fair values are estimated for categories of loans with similar financial characteristics. Loans are segregated by type and are then further segmented into fixed-rate and adjustable-rate interest terms to determine their fair value. The fair value of fixed-rate commercial and consumer loans is calculated by discounting scheduled cash flows through the estimated maturity of the loan using interest rates offered at the measurement date that reflect the credit and interest rate risk inherent in the loan. The estimate of maturity is based on the Corporation’s historical repayment experience. For residential mortgages, fair value is estimated by using market prices for sales of similar loans on the secondary market. The fair value of floating rate commercial and consumer loans approximates carrying value. Fair value for impaired loans is estimated using a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or if the loan is collateral dependent, at the fair value of the collateral. Loans are classified within Level 3 of the fair value hierarchy. Time Deposits The discounted values of cash flows using the rates currently offered for deposits of similar remaining maturities were used to estimate the fair value of time deposits. Time deposits are classified within Level 2 of the fair value hierarchy. Federal Home Loan Bank Advances Rates currently available to the Corporation for advances with similar terms and remaining maturities are used to estimate fair value of existing advances. FHLBB advances are categorized as Level 2. Junior Subordinated Debentures The fair value of the junior subordinated debentures is estimated using rates currently available to the Corporation for debentures with similar terms and maturities. Junior subordinated debentures are categorized as Level 2. The following tables present the carrying amount, estimated fair value and placement in the fair value hierarchy of the Corporation’s financial instruments. The tables exclude financial instruments for which the carrying value approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, FHLBB stock, accrued interest receivable and bank-owned life insurance. Financial liabilities for which the fair value approximates carrying value include non-maturity deposits and accrued interest payable. (Dollars in thousands) Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2016 Financial Assets: Securities held to maturity $15,633 $15,920 $— $15,920 $— Loans, net of allowance for loan losses 3,208,367 3,218,651 — — 3,218,651 Financial Liabilities: Time deposits $961,613 $962,374 $— $962,374 $— FHLBB advances 848,930 852,888 — 852,888 — Junior subordinated debentures 22,681 16,970 — 16,970 — (Dollars in thousands) Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2015 Financial Assets: Securities held to maturity $20,023 $20,516 $— $20,516 $— Loans, net of allowance for loan losses 2,986,058 3,004,782 — — 3,004,782 Financial Liabilities: Time deposits $833,898 $834,574 $— $834,574 $— FHLBB advances 378,973 388,275 — 388,275 — Junior subordinated debentures 22,681 16,468 — 16,468 —

Employee Benefits

Employee Benefits	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Benefits	Employee Benefits Defined Benefit Pension Plans The Corporation maintains a tax-qualified defined benefit pension plan for the benefit of certain eligible employees who were hired prior to October 1, 2007. The Corporation 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 defined benefit pension plan is funded on a current basis, in compliance with the requirements of ERISA. The non-qualified retirement plans provide for the designation of assets in rabbi trusts. Securities available for sale and other short-term investments designated for this purpose, with the carrying value of $11.7 million and $12.3 million are included in the Consolidated Balance Sheets at December 31, 2016 and 2015 , respectively. Pension benefit costs and benefit obligations incorporate various actuarial and other assumptions, including discount rates, mortality, rates of return on plan assets and compensation increases. Washington Trust evaluates these assumptions annually. Prior to 2016, a single weighted-average discount rate was used to calculate interest and service cost components of net periodic benefit cost. For 2016, Washington Trust utilized a "spot rate approach" in the calculation of interest and service cost. The spot rate approach applies separate discount rates for each projected benefit payment in the calculation of interest and service cost. This approach provides a more precise measurement of service and interest cost by improving the correlation between projected benefit cash flows and their corresponding spot rates. The following table presents the plans’ projected benefit obligations, fair value of plan assets and funded (unfunded)status: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2016 2015 2016 2015 Change in Benefit Obligation: Benefit obligation at beginning of period $67,550 $73,149 $13,015 $13,097 Service cost 2,148 2,459 122 78 Interest cost 2,576 2,928 432 490 Actuarial (gain) loss 3,888 (5,410 ) 374 88 Benefits paid (3,072 ) (5,430 ) (789 ) (738 ) Administrative expenses (139 ) (146 ) — — Benefit obligation at end of period 72,951 67,550 13,154 13,015 Change in Plan Assets: Fair value of plan assets at beginning of period 65,710 67,613 — — Actual return on plan assets 4,788 673 — — Employer contributions 8,500 3,000 789 738 Benefits paid (3,072 ) (5,430 ) (789 ) (738 ) Administrative expenses (139 ) (146 ) — — Fair value of plan assets at end of period 75,787 65,710 — — Funded (unfunded) status at end of period $2,836 ($1,840 ) ($13,154 ) ($13,015 ) As of December 31, 2016 , the funded status of the qualified defined benefit pension plan amounted to $2.8 million and was included in other assets in the Consolidated Balance Sheet. As of December 31, 2015 , the unfunded status of this qualified plan amounted to $1.8 million and was included in other liabilities in the Consolidated Balance Sheet. The unfunded status of the non-qualified defined benefit retirement plans was $13.2 million and $13.0 million , respectively, at December 31, 2016 and December 31, 2015 and was included in other liabilities in the Consolidated Balance Sheets. The following table presents components of accumulated other comprehensive income related to the qualified pension plan and non-qualified retirement plans, on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2016 2015 2016 2015 Net actuarial loss $15,593 $12,688 $4,519 $4,392 Prior service credit (62 ) (84 ) (1 ) (2 ) Total pre-tax amounts recognized in accumulated other comprehensive income $15,531 $12,604 $4,518 $4,390 The accumulated benefit obligation for the qualified pension plan was $65.8 million and $60.3 million at December 31, 2016 and 2015 , respectively. The accumulated benefit obligation for the non-qualified retirement plans amounted to $12.0 million and $11.7 million at December 31, 2016 and 2015 , respectively. The following table presents components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss), on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ended December 31, 2016 2015 2014 2016 2015 2014 Net Periodic Benefit Cost: Service cost $2,148 $2,459 $2,152 $122 $78 $46 Interest cost 2,576 2,928 2,891 432 490 478 Expected return on plan assets (4,633 ) (4,515 ) (4,063 ) — — — Amortization of prior service credit (23 ) (23 ) (23 ) (1 ) (1 ) (1 ) Recognized net actuarial loss 828 1,249 461 247 245 70 Net periodic benefit cost 896 2,098 1,418 800 812 593 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (on a pre-tax basis): Net (gain) loss 2,904 (2,816 ) 10,993 127 (156 ) 2,476 Prior service cost 23 23 23 1 1 1 Recognized in other comprehensive (loss) income 2,927 (2,793 ) 11,016 128 (155 ) 2,477 Total recognized in net periodic benefit cost and other comprehensive (loss) income $3,823 ($695 ) $12,434 $928 $657 $3,070 For the qualified pension plan, an estimated prior service credit of $23 thousand and net losses of $1.1 million will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost during the year 2017 . For the non-qualified retirement plans, an estimated prior service credit of $1 thousand and net losses of $261 thousand will be amortized from accumulated other comprehensive income (loss) into net periodic benefit cost during the year 2017 . Assumptions The following table presents the measurement date and weighted-average assumptions used to determine benefit obligations at December 31, 2016 and 2015 : Qualified Pension Plan Non-Qualified Retirement Plans 2016 2015 2016 2015 Measurement date Dec 31, 2016 Dec 31, 2015 Dec 31, 2016 Dec 31, 2015 Discount rate 4.18% 4.48% 4.00% 4.20% Rate of compensation increase 3.75 3.75 3.75 3.75 The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31, 2016 , 2015 and 2014 : Qualified Pension Plan Non-Qualified Retirement Plans 2016 2015 2014 2016 2015 2014 Measurement date Dec 31, 2015 Dec 31, 2014 Dec 31, 2013 Dec 31, 2015 Dec 31, 2014 Dec 31, 2013 Discount rate N/A 4.125% 4.875% N/A 3.90% 4.60% Equivalent single discount rate for benefit obligations 4.48% N/A N/A 4.20% N/A N/A Equivalent single discount rate for service cost 4.63 N/A N/A 4.59 N/A N/A Equivalent single discount rate for interest cost 3.88 N/A N/A 3.44 N/A N/A Expected long-term return on plan assets 6.75 7.25 7.25 N/A N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75 3.75 3.75 The expected long-term rate of return on plan assets is based on what the Corporation believes is realistically achievable based on the types of assets held by the plan and the plan’s investment practices. The assumption is updated annually, taking into account the asset allocation, historical asset return trends on the types of assets held and the current and expected economic conditions. Future decreases in the long-term rate of return assumption on plan assets would increase pension costs and, in general, may increase the requirement to make funding contributions to the plans. Future increases in the long-term rate of return on plan assets would have the opposite effect. The discount rate assumption for defined benefit pension plans is reset on the measurement date. Discount rates are selected for each plan by matching expected future benefit payments stream to a yield curve based on a selection of high- quality fixed-income debt securities. Future decreases in discount rates would increase the present value of pension obligations and increase our pension costs, while future increases in discount rates would have the opposite effect. Plan Assets The following tables present the fair values of the qualified pension plan’s assets: (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2016 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $2,880 $— $— $2,880 Obligations of U.S. government agencies and U.S. government-sponsored enterprises — 4,233 — 4,233 Obligations of states and political subdivisions — 3,418 — 3,418 Corporate bonds — 13,775 — 13,775 Common stocks 33,893 — — 33,893 Mutual funds 17,588 — — 17,588 Total plan assets $54,361 $21,426 $— $75,787 (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2015 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $1,598 $— $— $1,598 Obligations of U.S. government agencies and U.S. government-sponsored enterprises — 3,306 — 3,306 Obligations of states and political subdivisions — 3,438 — 3,438 Corporate bonds — 12,955 — 12,955 Common stocks 29,433 — — 29,433 Mutual funds 14,980 — — 14,980 Total plan assets $46,011 $19,699 $— $65,710 The qualified pension plan uses fair value measurements to record fair value adjustments to the securities held in its investment portfolio. When available, the qualified pension plan uses quoted market prices to determine the fair value of securities; such items are classified as Level 1. This category includes cash equivalents, common stocks and mutual funds which are exchange-traded. Level 2 securities in the qualified pension plan include debt securities with quoted prices, which are traded less frequently than exchange-traded instruments, whose values are determined using matrix pricing with inputs that are observable in the market or can be derived principally from or corroborated by observable market data. This category includes obligations of U.S. government agencies and U.S. government-sponsored enterprises, obligations of states and political subdivisions and corporate bonds. In certain cases where there is limited activity or less transparency around inputs to the valuation, securities may be classified as Level 3. As of December 31, 2016 and 2015 , the qualified pension plan did not have any securities in the Level 3 category. The following table present the asset allocations of the qualified pension plan, by asset category: December 31, 2016 2015 Asset Category: Equity securities 63.8 % 63.4 % Fixed income securities 32.4 34.6 Cash and cash equivalents 3.8 2.0 Total 100.0 % 100.0 % The assets of the qualified defined benefit pension plan trust (the “Pension Trust”) are managed to balance the needs of cash flow requirements and long-term rate of return. Cash inflow is typically comprised of investment income from portfolio holdings and Bank contributions, while cash outflow is for the purpose of paying plan benefits and certain plan expenses. As early as possible each year, the trustee is advised of the projected schedule of employer contributions and estimations of benefit payments. As a general rule, the trustee shall invest the funds so as to produce sufficient income to cover benefit payments and maintain a funded status that exceeds the regulatory requirements for tax-qualified defined benefit plans. The investment philosophy used for the Pension Trust emphasizes consistency of results over an extended market cycle, while reducing the impact of the volatility of the security markets upon investment results. The assets of the Pension Trust should be protected by substantial diversification of investments, providing exposure to a wide range of quality investment opportunities in various asset classes, with a high degree of liquidity. The investment objective with respect to the Pension Trust assets is to provide capital appreciation with a current income component. At any time, the portfolio will typically be invested in the following ranges: 50% to 70% in equities; 30% to 50% in fixed income; and 0% to 10% in cash and cash equivalents. The trustee investment manager will have authorization to invest within these ranges, making decisions based upon market conditions. Fixed income bond investments should be limited to those in the top four categories used by the major credit rating agencies. High yield bond funds may be used to provide exposure to this asset class as a diversification tool provided they do not exceed 10% of the portfolio. In order to reduce the volatility of the annual rate of return of the bond portfolio, attention will be given to the maturity structure of the portfolio in the light of money market conditions and interest rate forecasts. The assets of the Pension Trust will typically have a laddered maturity structure, avoiding large concentrations in any single year. Equity holdings provide opportunities for dividend and capital appreciation returns. Holdings will be appropriately diversified by maintaining broad exposure to large-, mid- and small-cap stocks as well as international equities. Concentration in small-cap, mid-cap and international equities is limited to no more than 20% , 20% and 30% of the equity portfolio, respectively. Investment selection and mix of equity holdings should be influenced by forecasts of economic activity, corporate profits and allocation among different segments of the economy while ensuring efficient diversification. The fair value of equity securities of any one issuer will not be permitted to exceed 10% of the total fair value of equity holdings of the Pension Trust. Investments in publicly traded real estate investment trust securities and low-risk derivatives securities such as callable securities, floating rate notes, mortgage- backed securities and treasury inflation protected securities, are permitted. Cash Flows Contributions The Internal Revenue Code permits flexibility in plan contributions so that normally a range of contributions is possible. The Corporation’s current funding policy has been generally to contribute the minimum required contribution and additional amounts up to the maximum deductible contribution. The Corporation expects to contribute $3.0 million to the qualified pension plan in 2017 . In addition, the Corporation expects to contribute $779 thousand in benefit payments to the non-qualified retirement plans in 2017 . Estimated Future Benefit Payments The following table presents the benefit payments, which reflect expected future service, as appropriate, expected to be paid: (Dollars in thousands) Qualified Pension Plan Non-Qualified Plans 2017 $3,709 $779 2018 3,064 772 2019 3,169 801 2020 3,991 895 2021 3,682 881 Years 2022 - 2026 24,864 4,248 401(k) Plan The Corporation’s 401(k) Plan provides a specified match of employee contributions for substantially all employees. In addition, substantially all employees hired after September 30, 2007, who are ineligible for participation in the qualified defined benefit pension plan, receive a non-elective employer contribution of 4% . Total employer matching contributions under this plan amounted to $2.3 million , $1.8 million and $1.8 million in 2016 , 2015 and 2014 , respectively. Other Incentive Plans The Corporation maintains several non-qualified incentive compensation plans. Substantially all employees participate in one of the incentive compensation plans. Incentive plans provide for annual or more frequent payments based on individual, business line and/or corporate performance targets (measured in terms of the Corporation’s net income, earnings per share and return on equity.) Total incentive based compensation amounted to $16.0 million , $14.3 million and $13.8 million in 2016 , 2015 and 2014 , respectively. In general, the terms of incentive plans are subject to annual renewal and may be terminated at any time by the Compensation Committee of the Board of Directors. Deferred Compensation Plan The Amended and Restated Nonqualified Deferred Compensation Plan provides supplemental retirement and tax benefits to directors and certain officers. The plan is funded primarily through pre-tax contributions made by the participants. The assets and liabilities of the Deferred Compensation Plan are recorded at fair value in the Corporation’s Consolidated Balance Sheets. The participants in the plan bear the risk of market fluctuations of the underlying assets. The accrued liability related to this plan amounted to $10.8 million and $8.6 million at December 31, 2016 and 2015 , respectively, and is included in other liabilities on the accompanying Consolidated Balance Sheets. The corresponding invested assets are reported in other assets.

Share-Based Compensation Arrang

Share-Based Compensation Arrangements	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation Arrangements	Share-Based Compensation Arrangements Washington Trust’s share-based compensation plans are described below. The 2013 Stock Option and Incentive Plan (the “2013 Plan”) was approved by shareholders on April 23, 2013. Under the 2013 Plan, the maximum number of shares of the Bancorp’s common stock to be issued is 1,748,250 . The 2013 Plan permits the granting of stock options and other equity incentives to officers, employees, directors and other key persons. The 2003 Stock Incentive Plan (the “2003 Plan”) was amended and restated and approved by shareholders in April 2009. The 2003 Plan amendments included increasing the maximum number of shares of Bancorp’s common stock to be issued under the 2003 Plan from 600,000 shares to 1,200,000 shares and increasing the number of shares that can be issued in the form of awards other than stock options or stock appreciation rights from 200,000 to 400,000 . The 2003 Plan permits the granting of stock options and other equity incentives to officers, employees, directors and other key persons. The exercise price of each stock option may not be less than the fair market value of the Bancorp’s common stock on the date of grant, and options shall have a term of no more than ten years. Stock options are designated as either non-qualified or incentive stock options. In general, the stock option price is payable in cash, by the delivery of shares of common stock already owned by the grantee, or a combination thereof. With respect only to non-qualified stock option grants issued under the 2013 Plan, the exercise may also be accomplished by withholding the exercise price from the number of shares that would otherwise be delivered upon a cash exercise of the option. The fair value of stock options on the date of grant is estimated using the Black-Scholes Option-Pricing Model. Awards of nonvested share units and nonvested performance share units are valued at the fair market value of the Bancorp’s common stock as of the award date. Performance share awards are granted in order to provide certain officers of the Corporation the opportunity to earn shares of common stock, the number of which is determined pursuant to, and subject to the attainment of, performance goals during a specified measurement period. The number of shares earned will range from zero to 200% of the target number of shares dependent upon the Corporation’s core return on equity and core earnings per share growth ranking compared to an industry peer group. Vesting of stock options and share awards may accelerate or may be subject to proportional vesting if there is a change in control, disability, retirement or death (as defined in the 2013 Plan and the 2003 Plan). The following table presents share-based compensation expense and the related income tax benefit recognized in the Consolidated Statements of Income for stock options, nonvested share awards and nonvested performance shares: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Share-based compensation expense $2,190 $2,074 $1,880 Related income tax benefit $810 $767 $676 Compensation expense for awards is recognized over the service period based on the fair value at the date of grant. Nonvested performance share unit compensation expense is based on the most recent performance assumption available and is adjusted as assumptions change. If the goals are not met, no compensation cost will be recognized and any recognized compensation costs will be reversed. Stock Options Washington Trust uses historical data to estimate stock option exercise and employee departure behavior used in the option-pricing model. The expected term of options granted was derived from the output of the option valuation model and represents the period of time that options granted are expected to be outstanding. Expected volatility was based on historical volatility of Washington Trust shares. The risk-free rate for periods within the contractual life of the stock option was based on the U.S. Treasury yield curve in effect at the date of grant. The following presents the assumptions used in determining the grant date fair value of the stock option awards granted to certain key employees: 2016 2015 2014 Options granted 53,400 48,600 25,850 Cliff vesting period (years) 3 3-5 3 Expected term (years) 7.5 7.5 8 Expected dividend yield 3.89 % 3.94 % 3.83 % Weighted average expected volatility 29.99 % 40.76 % 41.84 % Weighted average risk-free interest rate 1.66 % 1.95 % 2.27 % Weighted average grant-date fair value $7.92 $11.15 $9.92 The following table presents a summary of the status of Washington Trust’s stock options outstanding as of and for the year ended December 31, 2016 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (000’s) Beginning of period 309,116 $26.84 Granted 53,400 40.25 Exercised (143,237 ) 22.87 Forfeited or expired — — End of period 219,279 $32.70 7.17 $5,121 At end of period: Options exercisable 89,954 $25.34 4.77 $2,763 Options expected to vest in future periods 129,325 $37.82 8.85 $2,358 The total intrinsic value is the amount by which the fair value of the underlying stock exceeds the exercise price of an option on the exercise date. The following table presents additional information concerning options outstanding and options exercisable at December 31, 2016 : Options Outstanding Options Exercisable Exercise Price Ranges Number of Shares Weighted Average Remaining Life (Years) Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $15.01 to $20.00 13,200 2.93 $17.52 13,200 $17.52 $20.01 to $25.00 54,090 4.52 23.08 47,090 22.84 $25.01 to $30.00 — — — — — $30.01 to $35.00 51,689 6.90 32.76 29,564 32.77 $35.01 to $40.00 46,900 8.74 39.39 100 39.55 $40.01 to $45.00 53,400 9.80 40.25 — — 219,279 7.17 $32.70 89,954 $25.34 The total intrinsic value of stock options exercised during the years ended December 31, 2016 , 2015 and 2014 was $3.2 million , $1.2 million and $1.0 million , respectively. Nonvested Shares In 2016 , the Corporation granted to directors and certain key employees 22,175 nonvested share units, with 3 -year cliff vesting. In 2015 , the Corporation granted to directors and certain key employees 16,275 nonvested share units, with 3 - to 5 -year cliff vesting. In 2014 , the Corporation granted to certain key employees 11,630 nonvested share units with 3 -year cliff vesting. The following table presents a summary of the status of Washington Trust’s nonvested shares as of and for the year ended December 31, 2016 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 47,225 $33.46 Granted 22,175 38.82 Vested (16,797 ) 29.24 Forfeited (2,928 ) 36.11 End of period 49,675 $37.12 Nonvested Performance Shares The Corporation grants performance share units to certain executive officers providing the opportunity to earn shares of common stock over a 3 -year performance period based on various profitability results of the Corporation in comparison to a peer group. The number of shares earned can range from zero to 200% of the target number of shares depending upon the Corporation’s core return on equity and core earnings per share growth ranking among an industry peer group. The following table presents a summary of the performance share awards as of December 31, 2016 : Grant Date Fair Value per Share Current Performance Assumption Expected Number of Shares Performance shares awarded in: 2016 $36.11 140% 47,532 2015 38.02 142% 37,683 2014 34.66 133% 16,783 Total 101,998 The following table presents a summary of the status of Washington Trust’s performance share awards as of and for the year ended December 31, 2016 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 110,891 $32.81 Granted 47,532 36.11 Vested (48,090 ) 27.30 Forfeited (8,335 ) 37.26 End of period 101,998 $36.58 As of December 31, 2016 , there was $1.7 million of total unrecognized compensation cost related to share-based compensation arrangements (including stock options, nonvested share awards and performance share awards) granted under the Plans. That cost is expected to be recognized over a weighted average period of 1.76 years.

Business Segments

Business Segments	12 Months Ended
	Dec. 31, 2016
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 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. 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; equity in losses of unconsolidated investments in real estate limited partnerships; 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 the net gain on sale of business line and income from BOLI, as well as administrative and executive expenses not allocated to the operating segments and the residual impact of methodology allocations such as funds transfer pricing offsets. The following tables present the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Year ended December 31, 2016 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $91,221 ($66 ) $19,323 $110,478 Provision for loan losses 5,650 — — 5,650 Net interest income (expense) after provision for loan losses 85,571 (66 ) 19,323 104,828 Noninterest income 24,783 37,569 2,777 65,129 Noninterest expenses: Depreciation and amortization expense 2,771 1,940 224 4,935 Other noninterest expenses 58,452 25,239 12,477 96,168 Total noninterest expenses 61,223 27,179 12,701 101,103 Income before income taxes 49,131 10,324 9,399 68,854 Income tax expense 16,790 3,692 1,891 22,373 Net income $32,341 $6,632 $7,508 $46,481 Total assets at period end $3,354,633 $64,625 $961,857 $4,381,115 Expenditures for long-lived assets 2,267 464 381 3,112 (Dollars in thousands) Year ended December 31, 2015 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $84,757 ($47 ) $19,272 $103,982 Provision for loan losses 1,050 — — 1,050 Net interest income (expense) after provision for loan losses 83,707 (47 ) 19,272 102,932 Noninterest income 20,618 35,416 2,306 58,340 Noninterest expenses: Depreciation and amortization expense 2,584 1,488 213 4,285 Other noninterest expenses 55,203 25,632 11,809 92,644 Total noninterest expenses 57,787 27,120 12,022 96,929 Income before income taxes 46,538 8,249 9,556 64,343 Income tax expense 15,330 3,475 2,073 20,878 Net income $31,208 $4,774 $7,483 $43,465 Total assets at period end $3,152,231 $63,801 $555,572 $3,771,604 Expenditures for long-lived assets 4,714 411 354 5,479 (Dollars in thousands) Year ended December 31, 2014 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income $80,500 ($24 ) $19,029 $99,505 Provision for loan losses 1,850 — — 1,850 Net interest income (expense) after provision for loan losses 78,650 (24 ) 19,029 97,655 Noninterest income 17,575 33,378 8,062 59,015 Noninterest expenses: Depreciation and amortization expense 2,447 1,127 203 3,777 Other noninterest expenses 52,639 22,386 18,045 93,070 Total noninterest expenses 55,086 23,513 18,248 96,847 Income before income taxes 41,139 9,841 8,843 59,823 Income tax expense 13,497 3,724 1,778 18,999 Net income $27,642 $6,117 $7,065 $40,824 Total assets at period end $2,986,453 $52,720 $547,701 $3,586,874 Expenditures for long-lived assets 3,474 1,578 174 5,226

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) The following tables present the activity in other comprehensive income (loss): (Dollars in thousands) Year ended December 31, 2016 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale ($12,502 ) ($4,626 ) ($7,876 ) Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale ($12,502 ) ($4,626 ) ($7,876 ) Cash flow hedges: Changes in fair value of cash flow hedges (403 ) (146 ) (257 ) Net cash flow hedge losses reclassified into earnings — — — Net change in the fair value of cash flow hedges (403 ) (146 ) (257 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (4,106 ) (1,518 ) (2,588 ) Amortization of net actuarial losses (1) 1,075 397 678 Amortization of net prior service credits (1) (24 ) (9 ) (15 ) Net change in defined benefit plan obligations (3,055 ) (1,130 ) (1,925 ) Total other comprehensive loss ($15,960 ) ($5,902 ) ($10,058 ) (1) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2015 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale ($4,926 ) ($1,755 ) ($3,171 ) Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale ($4,926 ) ($1,755 ) ($3,171 ) Cash flow hedges: Changes in fair value of cash flow hedges (102 ) (49 ) (53 ) Net cash flow hedge losses reclassified into earnings (1) 469 172 297 Net change in the fair value of cash flow hedges 367 123 244 Defined benefit plan obligations: Defined benefit plan obligation adjustment 1,478 376 1,102 Amortization of net actuarial losses (2) 1,494 542 952 Amortization of net prior service credits (2) (24 ) (7 ) (17 ) Net change in defined benefit plan obligations 2,948 911 2,037 Total other comprehensive loss ($1,611 ) ($721 ) ($890 ) (1) The pre-tax amount is included in interest expense on junior subordinated debentures in the Consolidated Statements of Income. (2) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2014 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale $1,601 $580 $1,021 Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale 1,601 580 1,021 Cash flow hedges: Changes in fair value of cash flow hedges (56 ) (18 ) (38 ) Net cash flow hedge losses reclassified into earnings (1) 577 208 369 Net change in the fair value of cash flow hedges 521 190 331 Defined benefit plan obligations: Defined benefit plan obligation adjustment (14,000 ) (5,067 ) (8,933 ) Amortization of net actuarial losses (2) 531 190 341 Amortization of net prior service credits (2) (24 ) (8 ) (16 ) Net change in defined benefit plan obligations (13,493 ) (4,885 ) (8,608 ) Total other comprehensive loss ($11,371 ) ($4,115 ) ($7,256 ) (1) The pre-tax amount is included in interest expense on junior subordinated debentures in the Consolidated Statements of Income. (2) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income. The following tables present the changes in accumulated other comprehensive income (loss) by component, net of tax: (Dollars in thousands) Net Unrealized Losses on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2015 $1,051 ($43 ) ($10,707 ) ($9,699 ) Other comprehensive loss before reclassifications (7,876 ) (257 ) (2,588 ) (10,721 ) Amounts reclassified from accumulated other comprehensive income — — 663 663 Net other comprehensive loss income (7,876 ) (257 ) (1,925 ) (10,058 ) Balance at December 31, 2016 ($6,825 ) ($300 ) ($12,632 ) ($19,757 ) (Dollars in thousands) Net Unrealized Gains on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2014 $4,222 ($287 ) ($12,744 ) ($8,809 ) Other comprehensive (loss) income before reclassifications (3,171 ) (53 ) 1,102 (2,122 ) Amounts reclassified from accumulated other comprehensive income — 297 935 1,232 Net other comprehensive (loss) income (3,171 ) 244 2,037 (890 ) Balance at December 31, 2015 $1,051 ($43 ) ($10,707 ) ($9,699 ) (Dollars in thousands) Net Unrealized Gains on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2013 $3,201 ($618 ) ($4,136 ) ($1,553 ) Other comprehensive income (loss) before reclassifications 1,021 (38 ) (8,933 ) (7,950 ) Amounts reclassified from accumulated other comprehensive income — 369 325 694 Net other comprehensive income (loss) 1,021 331 (8,608 ) (7,256 ) Balance at December 31, 2014 $4,222 ($287 ) ($12,744 ) ($8,809 )

Earnings Per Common Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings per Common Share The following table presents the calculation of earnings per common share: (Dollars and shares in thousands, except per share amounts) Years ended December 31, 2016 2015 2014 Earnings per common share - basic: Net income $46,481 $43,465 $40,824 Less dividends and undistributed earnings allocated to participating securities (97 ) (126 ) (152 ) Net income applicable to common shareholders 46,384 43,339 40,672 Weighted average common shares 17,081 16,879 16,689 Earnings per common share - basic $2.72 $2.57 $2.44 Earnings per common share - diluted: Net income $46,481 $43,465 $40,824 Less dividends and undistributed earnings allocated to participating securities (97 ) (126 ) (151 ) Net income applicable to common shareholders 46,384 43,339 40,673 Weighted average common shares 17,081 16,879 16,689 Dilutive effect of common stock equivalents 127 188 183 Weighted average diluted common shares 17,208 17,067 16,872 Earnings per common share - diluted $2.70 $2.54 $2.41 Weighted average common stock equivalents, not included in common stock equivalents above because they were anti-dilutive, totaled 59,158 , 34,850 and 59,234 for the years ended December 31, 2016 , 2015 and 2014 , respectively.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Financial Instruments with Off-Balance Risk The Corporation is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers and to manage the Corporation’s exposure to fluctuations in interest rates. These financial instruments include commitments to extend credit, standby letters of credit, forward loan commitments, loan-related derivative contracts and interest rate risk management contracts. These instruments involve, to varying degrees, elements of credit risk in excess of the amount recognized in the Corporation’s Consolidated Balance Sheets. The contract or notional amounts of these instruments reflect the extent of involvement the Corporation has in particular classes of financial instruments. The Corporation’s credit policies with respect to interest rate swap agreements with commercial borrowers, commitments to extend credit and financial guarantees are similar to those used for loans. The interest rate swaps with other counterparties are generally subject to bilateral collateralization terms. The following table presents the contractual and notional amounts of financial instruments with off-balance sheet risk: (Dollars in thousands) December 31, 2016 2015 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $430,710 $360,795 Home equity lines 232,375 219,427 Other loans 49,708 44,164 Standby letters of credit 6,250 5,629 Financial instruments whose notional amounts exceed the amount of credit risk: Forward loan commitments: Interest rate lock commitments 49,502 49,712 Commitments to sell mortgage loans 78,896 87,498 Loan related derivative contracts: Interest rate swaps with customers 428,723 302,142 Mirror swaps with counterparties 428,723 302,142 Risk participation-in agreements 28,460 21,474 Interest rate risk management contracts: Interest rate swaps 60,000 — 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 1 year. At December 31, 2016 and 2015 , the maximum potential amount of undiscounted future payments, not reduced by amounts that may be recovered, totaled $6.3 million and $5.6 million , respectively. At December 31, 2016 and 2015 , there were no liabilities to beneficiaries resulting from standby letters of credit. Fee income on standby letters of credit was insignificant for the years ended December 31, 2016 , 2015 and 2014 . At December 31, 2016 and 2015 , a substantial portion of the standby letters of credit were supported by pledged collateral. The collateral obtained is determined based on management’s credit evaluation of the customer. Should the Corporation be required to make payments to the beneficiary, repayment from the customer to the Corporation is required. Forward Loan Commitments Interest rate lock commitments are extended to borrowers and relate to the origination of residential real estate mortgage loans held for sale. To mitigate the interest rate risk inherent in these rate locks, as well as closed residential real estate mortgage loans held for sale, forward commitments are established to sell individual residential real estate mortgage loans. Both interest rate lock commitments and commitments to sell residential real estate mortgage loans are derivative financial instruments. Leases At December 31, 2016 , the Corporation was committed to rent premises used in banking operations under non-cancelable operating leases. Rental expense under the operating leases amounted to $4.0 million , $3.5 million and $3.1 million for December 31, 2016 , 2015 and 2014 , respectively. The following table presents the minimum annual lease payments under the terms of these leases, exclusive of renewal provisions: (Dollars in thousands) Years ending December 31: 2017 $3,448 2018 3,163 2019 2,889 2020 2,210 2021 1,914 2022 and thereafter 25,148 Total minimum lease payments $38,772 Lease expiration dates range from 3 months to 24 years, with additional renewal options on certain leases ranging from 3 months to 5 years. Other Contingencies Litigation The Corporation is involved in various claims and legal proceedings arising out of the ordinary course of business. Management is of the opinion, based on its review with counsel of the development of such matters to date, that the ultimate disposition of such matters will not materially affect the consolidated financial position or results of operations of the Corporation. Other When selling a residential real estate mortgage loan or acting as originating agent on behalf of a third party, Washington Trust generally makes various representations and warranties. The specific representations and warranties depend on the nature of the transaction and the requirements of the buyer. Contractual liability may arise when the representations and warranties are breached. In the event of a breach of these representations and warranties, Washington Trust may be required to either repurchase the residential real estate mortgage loan (generally at unpaid principal balance plus accrued interest) with the identified defects or indemnify (“make-whole”) the investor for its losses. In the case of a repurchase, the Corporation will bear any subsequent credit loss on the residential real estate mortgage loan. Washington Trust has experienced an insignificant number of repurchase demands over a period of many years. As of December 31, 2016 and 2015 , the carrying value of loans repurchased due to representation and warranty claims was $524 thousand and $534 thousand , respectively. Washington Trust has recorded a reserve for its exposure to losses for premium recapture and the obligation to repurchase previously sold residential real estate mortgage loans. The reserve balance amounted to $180 thousand at both December 31, 2016 and December 31, 2015 and is included in other liabilities in the Consolidated Balance Sheets. Any change in the estimate is recorded in mortgage banking revenues in the Consolidated Statements of Income.

Parent Company Financial Statem

Parent Company Financial Statements	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Financial Statements	Parent Company Financial Statements The following tables present parent company only financial statements of the Bancorp, reflecting the investment in the Bank on the equity basis of accounting. The Statements of Changes in Shareholders’ Equity for the parent company only are identical to the Consolidated Statements of Changes in Shareholders’ Equity and are therefore not presented. Balance Sheets (Dollars in thousands, except par value) December 31, 2016 2015 Assets: Cash on deposit with bank subsidiary $1,743 $3,169 Interest-bearing balances due from banks — — Investment in subsidiaries at equity value 413,613 398,520 Dividends receivable from subsidiaries 6,518 5,082 Other assets 332 377 Total assets $422,206 $407,148 Liabilities: Junior subordinated debentures $22,681 $22,681 Dividends payable 6,628 6,075 Contingent consideration liability 2,047 2,945 Other liabilities 46 59 Total liabilities 31,402 31,760 Shareholders’ Equity: Common stock of $.0625 par value; authorized 60,000,000 shares at December 31, 2016 and 30,000,000 at December 31, 2015; issued and outstanding 17,170,820 shares at December 31, 2016 and 17,019,578 shares at December 31, 2015 1,073 1,064 Paid-in capital 115,123 110,949 Retained earnings 294,365 273,074 Accumulated other comprehensive loss (19,757 ) (9,699 ) Total shareholders’ equity 390,804 375,388 Total liabilities and shareholders’ equity $422,206 $407,148 Statements of Income (Dollars in thousands) Years ended December 31, 2016 2015 2014 Income: Dividends from subsidiaries $24,542 $23,399 $20,116 Other income 15 13 13 Total income 24,557 23,412 20,129 Expenses: Interest on junior subordinated debentures 491 871 964 Legal and professional fees 98 134 96 Acquisition related expenses — 308 — Change in fair value of contingent consideration (898 ) 41 — Other 282 254 253 Total expenses (27 ) 1,608 1,313 Income before income taxes 24,584 21,804 18,816 Income tax (expense) benefit (15 ) 557 454 Income before equity in undistributed earnings of subsidiaries 24,569 22,361 19,270 Equity in undistributed earnings of subsidiaries 21,912 21,104 21,554 Net income $46,481 $43,465 $40,824 Statements of Cash Flows (Dollars in thousands) Years ended December 31, 2016 2015 2014 Cash flow from operating activities: Net income $46,481 $43,465 $40,824 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of subsidiary (21,912 ) (21,104 ) (21,554 ) (Increase) decrease in dividend receivable (1,436 ) 19 (495 ) Decrease (increase) in other assets 45 (67 ) 183 (Decrease) increase in accrued expenses and other liabilities (12 ) 2,425 (516 ) Change in fair value of contingent consideration liability (898 ) 41 — Other, net (1,051 ) (3,363 ) (245 ) Net cash provided by operating activities 21,217 21,416 18,197 Cash flows from investing activities: Cash used in business combination, net of cash acquired — (1,671 ) — Net cash used in investing activities — (1,671 ) — Cash flows from financing activities: Proceeds from stock option exercises and issuance of other equity instruments 978 1,563 1,189 Tax benefit from stock option exercises and other equity instrument issuances 1,016 694 578 Cash dividends paid (24,637 ) (22,770 ) (19,722 ) Net cash used in financing activities (22,643 ) (20,513 ) (17,955 ) Net (decrease) increase in cash (1,426 ) (768 ) 242 Cash at beginning of year 3,169 3,937 3,695 Cash at end of year $1,743 $3,169 $3,937

Selected Quarterly Consolidated

Selected Quarterly Consolidated Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Consolidated Financial Data (Unaudited)	Selected Quarterly Consolidated Financial Data (Unaudited) (Dollars and shares in thousands, except per share amounts) 2016 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $32,969 $32,190 $33,256 $35,055 Interest expense 5,234 5,414 5,877 6,467 Net interest income 27,735 26,776 27,379 28,588 Provision for loan losses 500 450 1,800 2,900 Net interest income after provision for loan losses 27,235 26,326 25,579 25,688 Noninterest income 14,634 15,914 17,261 17,320 Noninterest expense 25,450 26,030 24,650 24,973 Income before income taxes 16,419 16,210 18,190 18,035 Income tax expense 5,484 5,153 5,863 5,873 Net income $10,935 $11,057 $12,327 $12,162 Weighted average common shares outstanding - basic 17,023 17,067 17,090 17,142 Weighted average common shares outstanding - diluted 17,157 17,194 17,203 17,245 Per share information: Basic earnings per common share $0.64 $0.65 $0.72 $0.71 Diluted earnings per common share $0.64 $0.64 $0.72 $0.70 Cash dividends declared per share $0.36 $0.36 $0.37 $0.37 (Dollars and shares in thousands, except per share amounts) 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $31,237 $31,510 $31,526 $31,477 Interest expense 5,535 5,482 5,529 5,222 Net interest income 25,702 26,028 25,997 26,255 Provision for loan losses — 100 200 750 Net interest income after provision for loan losses 25,702 25,928 25,797 25,505 Noninterest income 14,020 15,261 13,913 15,146 Noninterest expense 23,531 24,299 24,538 24,561 Income before income taxes 16,191 16,890 15,172 16,090 Income tax expense 5,181 5,387 4,964 5,346 Net income $11,010 $11,503 $10,208 $10,744 Weighted average common shares outstanding - basic 16,759 16,811 16,939 17,004 Weighted average common shares outstanding - diluted 16,939 16,989 17,102 17,167 Per share information: Basic earnings per common share $0.65 $0.68 $0.60 $0.63 Diluted earnings per common share $0.65 $0.68 $0.60 $0.62 Cash dividends declared per share $0.34 $0.34 $0.34 $0.34

Sale of Business Line

Sale of Business Line	12 Months Ended
	Dec. 31, 2016
Sale of Business Line [Abstract]
Sale of Business Line	Sale of Business Line On March 1, 2014, the Corporation sold its merchant processing service business line to a third party, resulting in a net gain of $6.3 million ; after-tax $4.0 million , or 24 cents per diluted share. In connection with the sale, Washington Trust incurred divestiture related costs of $355 thousand ; after-tax $227 thousand , or 1 cent per diluted share, in the first quarter of 2014. The net proceeds received from the sale totaled $7.2 million , including $900 thousand of deferred revenue that can be earned over a 5-year period by providing business referrals to the buyer. We have earned and recognized annual revenue of $180 thousand in 2016 , 2015 and 2014 , which was included in other income in the Consolidated Statements of Income. As of December 31, 2016 , $360 thousand of deferred revenue remained to be earned under this arrangement.

Summary of Significant Accoun33

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Consolidation	Washington Trust Bancorp, Inc. (the “Bancorp”) is a publicly-owned registered bank holding company that has elected to be a financial holding company. The Bancorp owns all of the outstanding common stock of The Washington Trust Company, of Westerly (the “Bank”), a Rhode Island chartered commercial bank founded in 1800. Through its subsidiaries, the Bancorp offers a complete product line of financial services including commercial, residential and consumer lending, retail and commercial deposit products, and wealth management services through its offices in Rhode Island, eastern Massachusetts and Connecticut. The consolidated financial statements include the accounts of the Bancorp and its subsidiaries (collectively, the “Corporation” or “Washington Trust”). All significant intercompany transactions have been eliminated.
Basis of Accounting	Certain previously reported amounts have been reclassified to conform to current year’s presentation. The accounting and reporting policies of the Corporation conform to 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. Material estimates that are particularly susceptible to change are the determination of the allowance for loan losses, the valuation of goodwill and identifiable intangible assets, the assessment of investment securities for impairment and accounting for defined benefit pension plans.
Cash and Cash Equivalents	Short-term Investments Short-term investments consist of highly liquid investments with a maturity date of three months or less when purchased and are considered to be cash equivalents. The Corporation’s short-term investments may be comprised of overnight federal funds sold, securities purchased under resale agreements, money market mutual funds and U.S. Treasury bills. Cash Flows For purposes of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks, and other short-term investments.
Securities	Securities Investments in debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and carried at amortized cost. Management determines the appropriate classification of securities at the time of purchase. Investments not classified as held to maturity are classified as available for sale. Securities available for sale consist of debt securities that are available for sale to respond to changes in market interest rates, liquidity needs, changes in funding sources and other similar factors. These assets are specifically identified and are carried at fair value. Changes in fair value of available for sale securities, net of applicable income taxes, are reported as a separate component of shareholders’ equity. Washington Trust does not have a trading portfolio. Premiums and discounts are amortized and accreted over the term of the securities on a method that approximates the level yield method. The amortization and accretion is included in interest income on securities. Interest income is recognized when earned. Realized gains or losses from sales of securities are determined using the specific identification method. The fair values of securities may be based on either quoted market prices or third party pricing services. When the fair value of an investment security is less than its amortized cost basis, the Corporation assesses whether the decline in value is other-than-temporary. The Corporation considers whether evidence indicating the cost of the investment is recoverable outweighs evidence to the contrary. Evidence considered in this assessment includes the reasons for impairment, the severity and duration of the impairment, changes in the value subsequent to the reporting date, forecasted performance of the issuer, changes in the dividend or interest payment practices of the issuer, changes in the credit rating of the issuer or the specific security, and the general market condition in the geographic area or industry in which the issuer operates. In determining whether an other-than-temporary impairment has occurred for debt securities, the Corporation compares the present value of cash flows expected to be collected from the security with the amortized cost of the security. If the present value of expected cash flows is less than the amortized cost of the security, then the entire amortized cost of the security will not be recovered; that is, a credit loss exists, and an other-than-temporary impairment shall be considered to have occurred. The credit loss component of an other-than-temporary impairment write-down for debt securities is recorded in earnings while the remaining portion of the impairment loss is recognized, net of tax, in other comprehensive income provided that the Corporation does not intend to sell the underlying debt security and it is more-likely-than-not that the Corporation would not have to sell the debt security prior to recovery of the unrealized loss, which may be to maturity. If the Corporation intended to sell any securities with an unrealized loss or it is more-likely-than-not that the Corporation would be required to sell the investment securities, before recovery of their amortized cost basis, then the entire unrealized loss would be recorded in earnings. See Note 5 for further discussion on the Corporation’s investment securities portfolio.
Federal Home Loan Bank Stock	Federal Home Loan Bank Stock The Bank is a member of the Federal Home Loan Bank of Boston (“FHLBB”). The FHLBB is a cooperative that provides services, including funding in the form of advances, to its member banking institutions. As a requirement of membership, the Bank must own a minimum amount of FHLBB stock, calculated periodically based primarily on its level of borrowings from the FHLBB. No market exists for shares of the FHLBB and therefore, they are carried at par value. FHLBB stock may be redeemed at par value 5 years following termination of FHLBB membership, subject to limitations which may be imposed by the FHLBB or its regulator, the Federal Housing Finance Board, to maintain capital adequacy of the FHLBB. While the Corporation currently has no intentions to terminate its FHLBB membership, the ability to redeem its investment in FHLBB stock would be subject to the conditions imposed by the FHLBB. The Corporation monitors its investment to determine if impairment exists. Based on the capital adequacy and the liquidity position of the FHLBB, management believes there is no impairment related to the carrying amount of the Corporation’s FHLBB stock as of December 31, 2016 .
Mortgage Loans Held for Sale	Mortgage Loans Held for Sale - Residential mortgage loans originated and intended for sale in the secondary market are classified as held for sale. The Corporation has elected the fair value option pursuant to Accounting Standards Codification (“ASC”) 825, “Financial Instruments” for certain closed loans intended for sale. ASC 825 allows for the irrevocable option to elect fair value accounting for the initial and subsequent measurement for certain financial assets and liabilities on a contract-by-contract basis that may otherwise not be required to be measured at fair value under other accounting standards. Washington Trust elected the fair value option for certain residential real estate mortgage loans held for sale pursuant to forward sale commitments in order to better match changes in fair values of the loans with changes in the fair value of the derivative forward loan sale contracts used to economically hedge them. Changes in the fair value of loans held for sale are recorded in earnings and are offset by changes in fair value relating to forward sale commitments and interest rate lock commitments. For residential mortgage loans intended for sale that are not accounted for under the fair value option, lower of cost or market (“LOCOM”) accounting is applied. Such loans are carried at lower of aggregate cost, net of unamortized deferred loan origination fees and costs, or fair value. Gains and losses on residential loan sales are recognized at the time of sale and included in mortgage banking revenues. Commissions received on mortgage loans brokered to various investors are recognized when received and included in mortgage banking revenues.
Loan Servicing Rights	Loan Servicing Rights - Rights to service mortgage loans for others are recognized as an asset, including rights acquired through both purchases and originations. Upon the sale of mortgage loans, a mortgage servicing asset is established, which represents the current estimated fair value based on the present value of estimated future net servicing income. The valuation model incorporates assumptions that market participants would use in estimating future net servicing income, such as the cost to service, the discount rate, ancillary income, prepayment speeds, and default rates and losses. Capitalized loan servicing rights are included in other assets. Mortgage servicing rights are amortized as an offset to mortgage banking revenues over the period of estimated net servicing income. They are periodically evaluated for impairment based on their fair value. Impairment is measured on an aggregated basis by stratifying the rights based on homogeneous characteristics such as note rate and loan type. The fair value is estimated based on the present value of expected cash flows, incorporating assumptions for discount rate, prepayment speed and servicing cost. Any impairment is recognized through a valuation allowance and as a reduction to mortgage banking revenues.
Loans	Loans Portfolio Loans - Loans held in the portfolio are stated at the principal amount outstanding, net of unamortized deferred loan origination fees and costs. Interest income is accrued on a level yield basis based on principal amounts outstanding. Deferred loan origination fees and costs are amortized as an adjustment to yield over the life of the related loans. Nonaccrual Loans - Loans, with the exception of certain well-secured loans that are in the process of collection, are placed on nonaccrual status and interest recognition is suspended when such loans are 90 days or more overdue with respect to principal and/or interest or sooner if considered appropriate by management. Well-secured loans are permitted to remain on accrual status provided that full collection of principal and interest is assured and the loan is in the process of collection. Loans are also placed on nonaccrual status when, in the opinion of management, full collection of principal and interest is doubtful. 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. Impaired Loans - Impaired loans are loans for which it is probable that the Corporation will not be able to collect all amounts due according to the contractual terms of the loan agreements and loans restructured in a troubled debt restructuring. Impairment is measured on a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or if the loan is collateral dependent, at the fair value. 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. Interest income on nonaccrual impaired loans is recognized as described above under the caption “Nonaccrual Loans.” Impaired accruing loans consist of those troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt. Troubled Debt Restructured Loans - Loans are considered to be troubled debt restructurings when the Corporation has granted concessions to a borrower due to the borrower’s financial condition that it otherwise would not have considered. These concessions may include modifications of the terms of the debt such as deferral of payments, extension of maturity, reduction of principal balance, reduction of the stated interest rate other than normal market rate adjustments, or a combination of these concessions. Debt may be bifurcated with separate terms for each tranche of the restructured debt. Restructuring of a loan in lieu of aggressively enforcing the collection of the loan may benefit the Corporation by increasing the ultimate probability of collection. Restructured loans are classified as accruing or non-accruing based on management’s assessment of the collectability of the loan. Loans which are already on nonaccrual status at the time of the restructuring generally remain on nonaccrual status for approximately 6 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.
Allowance for Loan Losses	Allowance for Loan Losses The allowance for loan losses is management’s best estimate of the risk of loss inherent in the loan portfolio as of the balance sheet date. The allowance is increased by provisions charged to earnings and by recoveries of amounts previously charged off, and is reduced by charge-offs on loans. Loan charge-offs are recognized when management believes the collectability of the principal balance outstanding is unlikely. Full or partial charge-offs on collateral dependent impaired loans are generally recognized when the collateral is deemed to be insufficient to support the carrying value of the loan. The level of the allowance is based on management’s ongoing review of the growth and composition of the loan portfolio, historical loss experience, estimated loss emergence period (the period from the event that triggers the eventual default until the actual loss is recognized with a charge-off), current economic conditions, analysis of asset quality and credit quality levels and trends, the performance of individual loans in relation to contract terms and other pertinent factors. A methodology is used to systematically measure the amount of estimated loan loss exposure inherent in the loan portfolio for the purposes of establishing a sufficient allowance for loan losses. The methodology includes: (1) the identification of loss allocations for individual loans deemed to be impaired and (2) the application of loss allocation factors for non-impaired loans based on historical loss experience and estimated loss emergence period, with adjustments for various exposures that management believes are not adequately represented by historical loss experience. Loss allocations for loans deemed to be impaired are measured on a discounted cash flow method based upon the loan’s contractual effective interest rate, or at the loan’s observable market price, or, if the loan is collateral dependent, at the fair value of the collateral. For collateral dependent loans for which repayment is dependent on the sale of the collateral, management adjusts the fair value for estimated costs to sell. For collateral dependent loans for which repayment is dependent on the operation of the collateral, such as accruing troubled debt restructured loans, estimated costs to sell are not incorporated into the measurement. Management may also adjust appraised values to reflect estimated market value declines or apply other discounts to appraised values for unobservable factors resulting from its knowledge of circumstances associated with the property. For loans that are collectively evaluated, loss allocation factors are derived by analyzing historical loss experience by loan segment over an established look-back period deemed to be relevant to the inherent risk of loss in the portfolios. Loans are segmented by loan type, collateral type, delinquency status and loan risk rating, where applicable. These loss allocation factors are adjusted to reflect the loss emergence period. These amounts are supplemented by certain qualitative risk factors reflecting management’s view of how losses may vary from those represented by historical loss rates. These qualitative risk factors include: 1) changes in lending policies and procedures, including changes in underwriting standards and collection, charge-off, and recovery practices not considered elsewhere in estimating credit losses; 2) changes in international, national, regional, and local economic and business conditions and developments that affect the collectability of the portfolio, including the condition of various market segments; 3) changes in the nature and volume of the portfolio and in the terms of loans; 4) changes in the experience, ability, and depth of lending management and other relevant staff; 5) changes in the volume and severity of past due loans, the volume of nonaccrual loans, and the volume and severity of adversely classified or rated loans; 6) changes in the quality of the institution’s loan review system; 7) changes in the value of underlying collateral for collateral dependent loans; 8) the existence and effect of any concentrations of credit, and changes in the level of such concentrations; and 9) the effect of other external factors such as legal and regulatory requirements on the level of estimated credit losses in the institution’s existing portfolio. Because the methodology is based upon historical experience and trends, current economic data, as well as management’s judgment, factors may arise that result in different estimations. Adversely different conditions or assumptions could lead to increases in the allowance. In addition, various regulatory agencies periodically review the allowance for loan losses. Such agencies may require additions to the allowance based on their judgments about information available to them at the time of their examination. The allowance is an estimate, and ultimate losses may vary from management’s estimate. Changes in the estimate are recorded in the results of operations in the period in which they become known, along with provisions for estimated losses incurred during that period.
Premises and Equipment	Premises and Equipment Premises and equipment are stated at cost less accumulated depreciation. Depreciation for financial reporting purposes is calculated on the straight-line method over the estimated useful lives of assets. Expenditures for major additions and improvements are capitalized while the costs of current maintenance and repairs are charged to operating expenses. The estimated useful lives of premises and improvements range from 5 to 40 years. For furniture, fixtures and equipment, the estimated useful lives range from 3 to 20 years.
Goodwill and Other Identifiable Intangible Assets	Goodwill and Other Identifiable Intangible Assets The Corporation allocated the cost of an acquired entity to the assets acquired and liabilities assumed based on their estimated fair values at the date of acquisition. Other intangible assets identified in acquisitions primarily consist of wealth management advisory contracts. The value attributed to other intangible assets was based on the time period over which they are expected to generate economic benefits. The excess of the purchase price for acquisitions over the fair value of the net assets acquired, including other intangible assets, was recorded as goodwill. Goodwill is not amortized but is tested for impairment at the reporting unit level, defined as the segment level, at least annually in the fourth quarter or more frequently whenever events or circumstances occur that indicate that it is more-likely-than-not that an impairment loss has occurred. In assessing impairment, the Corporation has the option to perform a qualitative analysis to determine whether the existence of events or circumstances leads to a determination that it is more-likely-than-not that the fair value of the reporting unit is less than its carrying amount. If, after assessing the totality of such events or circumstances, we determine it is not more-likely-than-not that the fair value of a reporting unit is less than its carrying amount, then we would not be required to perform a two-step impairment test. The Corporation has not opted to perform this qualitative analysis. Goodwill is tested for impairment using the two-step quantitative impairment analysis described below. The first step (“Step 1”) of the quantitative impairment analysis requires a comparison of each reporting unit’s fair value to its carrying value to identify potential impairment. The second step (“Step 2”) of the analysis is necessary only if a reporting unit’s carrying amount exceeds its fair value. Step 2 is a more detailed analysis, which involves measuring the excess of the fair value of the reporting unit, as determined in Step 1, over the aggregate fair value of the individual assets, liabilities, and identifiable intangibles as if the reporting unit was being acquired in a business combination. Goodwill impairment exists when a reporting unit’s carrying value of goodwill exceeds its implied fair value. Significant judgment is applied when goodwill is assessed for impairment. This judgment includes, but may not be limited to, the selection of appropriate discount rates, the identification of relevant market comparables and the development of cash flow projections. The selection and weighting of the various fair value techniques may result in a higher or lower fair value. Judgment is applied in determining the weightings that are most representative of fair value. Other intangible assets with definite lives are tested for impairment whenever events or circumstances occur that indicate that the carrying amount may not be recoverable. If applicable, the Corporation tests each of the intangibles by comparing the carrying value of the intangible asset to the sum of undiscounted cash flows expected to be generated by the asset. If the carrying amount of the asset exceeded its undiscounted cash flows, then an impairment loss would be recognized for the amount by which the carrying amount exceeds its fair value.
Impairment of Long-Lived Assets Other than Goodwill	Impairment of Long - Lived Assets Other than Goodwill Long-lived assets are reviewed for impairment whenever events or changes in business circumstances indicate that the the carrying amount may not be fully recoverable. If impairment is determined to exist, any related impairment loss is calculated based on fair value. Impairment losses on assets to be disposed of, if any, are based on the estimated proceeds to be received, less costs of disposal.
Property Acquired through Foreclosure or Repossession	Property Acquired through Foreclosure or Repossession Property acquired through foreclosure or repossession is carried at the lower of cost or fair value less estimated costs to sell. Fair value of such assets is determined based on independent appraisals and other relevant factors. Any write-down to fair value at the time of foreclosure or repossession is charged to the allowance for loan losses. A valuation allowance is maintained for declines in market value and for estimated selling expenses. Increases to the valuation allowance, expenses associated with ownership of these properties, and gains and losses from their sale are included in foreclosed property costs. Loans that are substantively repossessed include only those loans for which the Corporation has obtained control of the collateral, but has not completed legal foreclosure proceedings.
Bank-Owned Life Insurance	Bank-Owned Life Insurance The investment in BOLI represents the cash surrender value of life insurance policies on the lives of certain employees who have provided positive consent allowing the Bank to be the beneficiary of such policies. Increases in the cash value of the policies, as well as insurance proceeds received, are recorded in noninterest income, and are not subject to income taxes. The financial strength of the insurance carrier is reviewed prior to the purchase of BOLI and annually thereafter.
Investment in Real Estate Limited Partnership	Investment in Real Estate Limited Partnership Washington Trust has a 99.9% ownership interest in two real estate limited partnerships that renovate, own and operate two low-income housing complexes. Washington Trust neither actively participates nor has a controlling interest in these limited partnerships and accounts for its investments under the equity method of accounting. The carrying value of the investments is recorded in other assets on the Consolidated Balance Sheet. Net losses generated by the partnership are recorded as a reduction to Washington Trust’s investment and as a reduction of noninterest income in the Consolidated Statements of Income. Tax credits generated by the partnership are recorded as a reduction in the income tax provision in the year they are allowed for tax reporting purposes. The results of operations of the real estate limited partnerships are periodically reviewed to determine if the partnership generates sufficient operating cash flow to fund its current obligations. In addition, the current value of the underlying properties is compared to the outstanding debt obligations. If it is determined that the investment is permanently impaired, the carrying value will be written down to the estimated realizable value.
Transfers and Servicing of Assets and Extinguishments of Liabilities	Transfers and Servicing of Assets and Extinguishments of Liabilities The accounting for transfers and servicing of financial assets and extinguishments of liabilities is based on consistent application of a financial components approach that focuses on control. This approach distinguishes transfers of financial assets that are sales from transfers that are secured borrowings. After a transfer of financial assets, the Corporation recognizes all financial and servicing assets it controls and liabilities it has incurred and derecognizes financial assets it no longer controls and liabilities that have been extinguished. This financial components approach focuses on the assets and liabilities that exist after the transfer. Many of these assets and liabilities are components of financial assets that existed prior to the transfer. If a transfer does not meet the criteria for a sale, the transfer is accounted for as a secured borrowing with a pledge of collateral.
Fee Revenue	Fee Revenue Wealth management revenues include asset-based revenues (trust and investment advisory fees and mutual fund fees) that are primarily accrued as earned based upon a percentage of asset values under administration. Also included in wealth management revenues are transaction-based revenues (financial planning fees, commissions and other service fees), which are recognized as revenue to the extent that services have been completed. Fee revenue from deposit service charges is generally recognized when earned.
Pension Costs	Pension Costs Pension benefits are accounted for using the net periodic benefit cost method, which recognizes the compensation cost of an employee’s pension benefit over that employee’s approximate service period. Pension benefit costs and benefit obligations incorporate various actuarial and other assumptions, including discount rates, mortality, rates of return on plan assets and compensation increases. Washington Trust evaluates these assumptions on an annual basis and makes modifications to the assumptions based on current rates and trends when it is appropriate to so do. The effect of modifications to those assumptions is recorded in other comprehensive income (loss) and amortized to net periodic cost over future periods. Washington Trust believes that the assumptions utilized in recording its obligations under its plans are reasonable based on its experience and market conditions. The funded status of defined benefit pension plans, measured as the difference between the fair value of plan assets and the projected benefit obligation, is recognized in the Consolidated Balance Sheet. The changes in the funded status of the defined benefit plans, including actuarial gains and losses and prior service costs and credits, are recognized in comprehensive income in the year in which the changes occur.
Share-Based Compensation	Share-Based Compensation Share-based compensation plans provide for awards of stock options and other equity incentives, including nonvested share units and nonvested performance share units. Compensation expense for awards is recognized over the service period based on the fair value at the date of grant. The Corporation estimates grant date fair value for stock options using the Black-Scholes option-pricing model. Awards of nonvested share units and nonvested performance share units are valued at the fair market value of the Bancorp’s common stock as of the award date. Nonvested performance share unit compensation expense is based on the most recent performance assumption available and is adjusted as assumptions change. If the goals are not met, no compensation cost will be recognized and any recognized compensation costs will be reversed. Excess tax benefits (expenses) related to stock option exercises and issuance of other compensation-related equity instruments are reflected on the Consolidated Statements of Cash Flows as financing activity.
Income Taxes	Income Taxes Income tax expense is determined based on the asset and liability method, whereby deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The Corporation recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Corporation records interest related to unrecognized tax benefits in income tax expense. Penalties, if incurred, would be recognized as a component of income tax expense.
Segment Reporting	Segment Reporting 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. The methodologies and organizational hierarchies that define the business segments are periodically reviewed and revised. Results may be restated, when necessary, to reflect changes in organizational structure or allocation methodology. Any changes in estimates and allocations that may affect the reported results of any business segment will not affect the consolidated financial position or results of operations of Washington Trust as a whole. Management uses certain methodologies to allocate income and expenses to the business lines. A funds transfer pricing 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. Certain indirect expenses are allocated to segments. These include support unit expenses such as technology, operations and other support functions.
Earnings Per Share (EPS)	Earnings Per Share (“EPS”) The Corporation utilizes the two-class method earnings allocation formula to determine earnings per share of each class of stock according to dividends and participation rights in undistributed earnings. Share based payments that entitle holders to receive non-forfeitable dividends before vesting are considered participating securities and included in earnings allocation for computing basic earnings per share under this method. Undistributed income is allocated to common shareholders and participating securities under the two-class method based upon the proportion of each to the total weighted average shares available. Under the two-class method, basic earnings per common share is computed by dividing net earnings allocated to common stock by the weighted-average number of common shares outstanding. Diluted earnings per common share is computed using the weighted-average number of shares determined for the basic earnings per common share computation plus the dilutive effect of common stock equivalents.
Comprehensive Income	Comprehensive Income Comprehensive income is defined as all changes in equity, except for those resulting from transactions with shareholders. Net income is a component of comprehensive income. All other components are referred to in the aggregate as other comprehensive income (loss) .
Guarantees	Guarantees Standby letters of credit are considered a guarantee of the Corporation. Standby letters of credit are conditional commitments issued to guarantee the performance of a customer to a third party. The credit risk involved in issuing standby letters of credit is essentially the same as that involved in extending loan facilities to customers. Under the standby letters of credit, the Corporation is required to make payments to the beneficiary of the letters of credit upon request by the beneficiary contingent upon the customer’s failure to perform under the terms of the underlying contract with the beneficiary.
Derivative Insturments and Hedging Activities	Derivative Instruments and Hedging Activities Derivatives are recognized as either assets or liabilities on the balance sheet and are measured at fair value. The accounting for changes in the fair value of derivatives depends on the intended use of the derivative and resulting designation. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivative are recorded in other comprehensive income (loss) and subsequently reclassified to earnings when gains or losses are realized. The ineffective portion of changes in the fair value is recognized directly in earnings as interest expense. For derivatives not designated as hedges, changes in fair value of the derivative instruments are recognized in earnings, in noninterest income. The accrued net settlements on derivatives that qualify for hedge accounting are recorded in interest income or interest expense based on the item being hedged. Changes in fair value of derivatives including accrued net settlements that do not qualify for hedge accounting are reported in noninterest income. When a cash flow hedge is discontinued, but the hedged cash flows or forecasted transaction is still expected to occur, changes in value that were accumulated in other comprehensive income (loss) are amortized or accreted into earnings over the same periods which the hedged transactions will affect earnings. By using certain derivative financial instruments, the Corporation exposes itself to credit risk. Credit risk is the failure of the counterparty to perform under the terms of the derivative contract. When the fair value of a derivative contract is positive, the counterparty owes the Corporation, which creates credit risk for the Corporation. When the fair value of a derivative contract is negative, the Corporation owes the counterparty and, therefore, it does not possess credit risk. The credit risk in derivative instruments is minimized by entering into transactions with highly rated counterparties that management believes to be creditworthy.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC Topic 820, “Fair Value Measurements and Disclosures”, establishes a framework for measuring fair value and expands disclosures about fair value measurements. The required disclosures about fair value measurements have been included in Note 16 .

Acquisition (Tables)

Acquisition (Tables)	12 Months Ended
	Dec. 31, 2016
Acquisition [Abstract]
Acquisition	The following table presents the estimated fair value of identifiable assets acquired and liabilities assumed as of the date of acquisition, August 1, 2015: (Dollars in thousands) Fair Value Assets: Cash $10 Deferred tax assets 653 Goodwill 5,945 Identifiable intangible assets 7,515 Other assets 202 Total assets acquired $14,325 Liabilities: Contingent consideration liability $2,904 Deferred tax liabilities 2,803 Other liabilities 1,507 Total liabilities assumed $7,214 Net assets acquired $7,111

Securities (Tables)

Securities (Tables)	12 Months Ended
	Dec. 31, 2016
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) December 31, 2016 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Securities Available for Sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $111,483 $7 ($3,050 ) $108,440 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 592,833 4,923 (9,671 ) 588,085 Obligations of states and political subdivisions 14,423 62 — 14,485 Individual name issuer trust preferred debt securities 29,851 — (3,115 ) 26,736 Corporate bonds 2,155 16 (5 ) 2,166 Total securities available for sale $750,745 $5,008 ($15,841 ) $739,912 Held to Maturity: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $15,633 $287 $— $15,920 Total securities held to maturity 15,633 287 — 15,920 Total securities $766,378 $5,295 ($15,841 ) $755,832 (Dollars in thousands) December 31, 2015 Amortized Cost Unrealized Gains Unrealized Losses Fair Value Securities Available for Sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $77,330 $73 ($388 ) $77,015 Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 228,908 6,398 (450 ) 234,856 Obligations of states and political subdivisions 35,353 727 — 36,080 Individual name issuer trust preferred debt securities 29,815 — (4,677 ) 25,138 Corporate bonds 1,970 5 (20 ) 1,955 Total securities available for sale $373,376 $7,203 ($5,535 ) $375,044 Held to Maturity: Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises $20,023 $493 $— $20,516 Total securities held to maturity 20,023 493 — 20,516 Total securities $393,399 $7,696 ($5,535 ) $395,560
Securities by Contractual Maturity	The schedule of maturities of debt securities available for sale and held to maturity 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 Held to Maturity December 31, 2016 Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $75,499 $74,921 $2,605 $2,653 Due after one year to five years 254,974 252,489 7,157 7,288 Due after five years to ten years 239,622 236,175 4,414 4,495 Due after ten years 180,650 176,327 1,457 1,484 Total securities $750,745 $739,912 $15,633 $15,920 Included in the above table were debt securities with an amortized cost balance of $155.6 million and a fair value of $149.5 million at December 31, 2016 that are callable at the discretion of the issuers. Final maturities of the callable securities range from 2 months to 20 years, with call features ranging from 1 month to 5 years.
Securities in a Continuous Unrealized Loss Position	The following tables summarize temporarily impaired securities, segregated by length of time the securities have been in a continuous unrealized loss position: (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2016 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government agencies and U.S. government-sponsored enterprises 10 $98,433 ($3,050 ) — $— $— 10 $98,433 ($3,050 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 35 407,073 (9,671 ) — — — 35 407,073 (9,671 ) Individual name issuer trust preferred debt securities — — — 10 26,736 (3,115 ) 10 26,736 (3,115 ) Corporate bonds 2 400 (5 ) — — — 2 400 (5 ) Total temporarily impaired securities 47 $505,906 ($12,726 ) 10 $26,736 ($3,115 ) 57 $532,642 ($15,841 ) (Dollars in thousands) Less than 12 Months 12 Months or Longer Total December 31, 2015 # Fair Value Unrealized Losses # Fair Value Unrealized Losses # Fair Value Unrealized Losses Obligations of U.S. government agencies and U.S. government-sponsored enterprises 4 $34,767 ($388 ) — $— $— 4 $34,767 ($388 ) Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 9 61,764 (450 ) — — — 9 61,764 (450 ) Individual name issuer trust preferred debt securities — — — 10 25,138 (4,677 ) 10 25,138 (4,677 ) Corporate bonds 3 1,235 (20 ) — — — 3 1,235 (20 ) Total temporarily impaired securities 16 $97,766 ($858 ) 10 $25,138 ($4,677 ) 26 $122,904 ($5,535 )

Loans (Tables)

Loans (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Summary of Loans	The following is a summary of loans: (Dollars in thousands) December 31, 2016 December 31, 2015 Amount % Amount % Commercial: Mortgages (1) $1,074,186 33 % $931,953 31 % Construction & development (2) 121,371 4 122,297 4 Commercial & industrial (3) 576,109 18 600,297 20 Total commercial 1,771,666 55 1,654,547 55 Residential real estate: Mortgages 1,094,824 34 984,437 33 Homeowner construction 27,924 1 29,118 1 Total residential real estate 1,122,748 35 1,013,555 34 Consumer: Home equity lines 264,200 8 255,565 8 Home equity loans 37,272 1 46,649 2 Other (4) 38,485 1 42,811 1 Total consumer 339,957 10 345,025 11 Total loans (5) $3,234,371 100 % $3,013,127 100 % (1) Loans primarily secured by income producing property. (2) Loans for construction of commercial properties, loans to developers for construction of residential properties and loans for land development. (3) Loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate. (4) Loans to individuals secured by general aviation aircraft and other personal installment loans. (5) Includes net unamortized loan origination costs of $3.0 million and $2.6 million , respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand , respectively, at December 31, 2016 and 2015 .
Nonaccrual Loans	The following is a summary of nonaccrual loans, segregated by class of loans: (Dollars in thousands) December 31, 2016 2015 Commercial: Mortgages $7,811 $5,711 Construction & development — — Commercial & industrial 1,337 3,018 Residential real estate: Mortgages 11,736 10,666 Homeowner construction — — Consumer: Home equity lines — 528 Home equity loans 1,058 1,124 Other 116 — Total nonaccrual loans $22,058 $21,047 Accruing loans 90 days or more past due $— $—
Past Due Loans	The following tables present an aging analysis of past due loans, segregated by class of loans: (Dollars in thousands) Days Past Due December 31, 2016 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Mortgages $901 $— $7,807 $8,708 $1,065,478 $1,074,186 Construction & development — — — — 121,371 121,371 Commercial & industrial 409 — 745 1,154 574,955 576,109 Residential real estate: Mortgages 5,381 652 6,193 12,226 1,082,598 1,094,824 Homeowner construction — — — — 27,924 27,924 Consumer: Home equity lines 655 26 — 681 263,519 264,200 Home equity loans 776 76 658 1,510 35,762 37,272 Other 32 1 110 143 38,342 38,485 Total loans $8,154 $755 $15,513 $24,422 $3,209,949 $3,234,371 (Dollars in thousands) Days Past Due December 31, 2015 30-59 60-89 Over 90 Total Past Due Current Total Loans Commercial: Mortgages $51 $— $4,504 $4,555 $927,398 $931,953 Construction & development — — — — 122,297 122,297 Commercial & industrial 405 9 48 462 599,835 600,297 Residential real estate: Mortgages 3,028 2,964 3,294 9,286 975,151 984,437 Homeowner construction — — — — 29,118 29,118 Consumer: Home equity lines 883 373 518 1,774 253,791 255,565 Home equity loans 748 490 222 1,460 45,189 46,649 Other 22 — — 22 42,789 42,811 Total loans $5,137 $3,836 $8,586 $17,559 $2,995,568 $3,013,127
Impaired Loans	The following is a summary of impaired loans: (Dollars in thousands) Recorded Investment (1) Unpaid Principal Related Allowance December 31, 2016 2015 2016 2015 2016 2015 No Related Allowance Recorded: Commercial: Mortgages $4,676 $4,292 $9,019 $5,101 $— $— Construction & development — — — — — — Commercial & industrial 6,458 1,849 6,550 1,869 — — Residential real estate: Mortgages 14,385 8,441 14,569 8,826 — — Homeowner construction — — — — — — Consumer: Home equity lines — 6 — 64 — — Home equity loans 1,137 530 1,177 539 — — Other 116 — 116 — — — Subtotal 26,772 15,118 31,431 16,399 — — With Related Allowance Recorded: Commercial: Mortgages 5,104 10,873 6,087 10,855 448 1,633 Construction & development — — — — — — Commercial & industrial 662 2,024 699 2,248 3 771 Residential real estate: Mortgages 1,285 2,895 1,310 2,941 151 156 Homeowner construction — — — — — — Consumer: Home equity lines — 522 — 522 — 2 Home equity loans — 679 — 783 — 21 Other 28 145 29 144 4 — Subtotal 7,079 17,138 8,125 17,493 606 2,583 Total impaired loans $33,851 $32,256 $39,556 $33,892 $606 $2,583 Total: Commercial $16,900 $19,038 $22,355 $20,073 $451 $2,404 Residential real estate 15,670 11,336 15,879 11,767 151 156 Consumer 1,281 1,882 1,322 2,052 4 23 Total impaired loans $33,851 $32,256 $39,556 $33,892 $606 $2,583 (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 impaired accruing loans (troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt), the recorded investment also includes accrued interest. The following table presents the average recorded investment balance of impaired loans and interest income recognized on impaired loans segregated by loan class: (Dollars in thousands) Average Recorded Investment Interest Income Recognized Years ended December 31, 2016 2015 2014 2016 2015 2014 Commercial: Mortgages $13,201 $14,847 $22,971 $239 $327 $658 Construction & development — — — — — — Commercial & industrial 3,540 3,415 2,499 99 130 126 Residential real estate: Mortgages 12,848 5,423 4,006 322 147 101 Homeowner construction — — — — — — Consumer: Home equity lines 354 228 97 10 1 2 Home equity loans 1,233 487 100 38 11 4 Other 147 210 119 11 10 8 Totals $31,323 $24,610 $29,792 $719 $626 $899
Troubled Debt Restructurings	The following table presents loans modified as a troubled debt restructuring: (Dollars in thousands) Outstanding Recorded Investment (1) # of Loans Pre-Modifications Post-Modifications Years ended December 31, 2016 2015 2016 2015 2016 2015 Commercial: Mortgages 1 1 $776 $1,190 $776 $1,190 Construction & development — — — — — — Commercial & industrial 9 3 6,229 584 6,229 584 Residential real estate: Mortgages 3 3 4,386 619 4,386 619 Homeowner construction — — — — — — Consumer: Home equity lines — — — — — — Home equity loans — 1 — 70 — 70 Other — 1 — 35 — 35 Totals 13 9 $11,391 $2,498 $11,391 $2,498 (1) 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.
Troubled Debt Restructurings, Type of Modification	The following table provides information on how loans were modified as a troubled debt restructuring: (Dollars in thousands) Years ended December 31, 2016 2015 Below-market interest rate concession $— $335 Payment deferral 1,111 903 Maturity / amortization concession 683 70 Interest only payments 4,326 — Combination (1) 5,271 1,190 Total $11,391 $2,498 (1) Loans included in this classification were modified with a combination of any two of the concessions listed in this table.
Credit Quality Indicators - Commercial	The following table presents the commercial loan portfolio, segregated by category of credit quality indicator: (Dollars in thousands) Pass Special Mention Classified December 31, 2016 2015 2016 2015 2016 2015 Mortgages $1,065,358 $914,774 $776 $3,035 $8,052 $14,144 Construction & development 121,371 122,297 — — — — Commercial & industrial 559,416 577,036 8,938 12,012 7,755 11,249 Total commercial loans $1,746,145 $1,614,107 $9,714 $15,047 $15,807 $25,393
Credit Quality Indicators - Residential & Consumer	The following table presents the residential and consumer loan portfolios, segregated by category of credit quality indicator: (Dollars in thousands) Current and Under 90 Days Past Due Over 90 Days Past Due December 31, 2016 2015 2016 2015 Residential real estate: Accruing mortgages $1,083,088 $973,771 $— $— Nonaccrual mortgages 5,543 7,372 6,193 3,294 Homeowner construction 27,924 29,118 — — Total residential loans $1,116,555 $1,010,261 $6,193 $3,294 Consumer: Home equity lines $264,200 $255,047 $— $518 Home equity loans 36,614 46,427 658 222 Other 38,375 42,811 110 — Total consumer loans $339,189 $344,285 $768 $740
Analysis of Loan Servicing Rights	The following table presents an analysis of loan servicing rights: (Dollars in thousands) Loan Servicing Rights Valuation Allowance Total Balance at December 31, 2013 $2,767 ($69 ) $2,698 Loan servicing rights capitalized 869 — 869 Amortization (647 ) — (647 ) Decrease in impairment reserve — 67 67 Balance at December 31, 2014 2,989 (2 ) 2,987 Loan servicing rights capitalized 1,406 — 1,406 Amortization (1,047 ) — (1,047 ) Decrease in impairment reserve — 1 1 Balance at December 31, 2015 3,348 (1 ) 3,347 Loan servicing rights capitalized 1,412 — 1,412 Amortization (1,267 ) — (1,267 ) Decrease in impairment reserve — 1 1 Balance at December 31, 2016 $3,493 $— $3,493
Amortization Expense Related to Loan Servicing Assets	The following table presents estimated aggregate amortization expense related to loan servicing assets: (Dollars in thousands) Years ending December 31: 2017 $1,137 2018 767 2019 517 2020 349 2021 235 Thereafter 488 Total estimated amortization expense $3,493
Loans Serviced for Others, by Type of Loan	The following table presents the balance of loans serviced for others, by type of loan: (Dollars in thousands) December 31, 2016 2015 Residential mortgages $522,766 $458,629 Commercial loans 101,317 109,173 Total $624,083 $567,802

Allowance for Loan Losses (Tabl

Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Allowance for Loan Losses Rollforward Analysis	The following table presents the activity in the allowance for loan losses for the year ended December 31, 2016 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Total Beginning Balance $9,140 $1,758 $8,202 $19,100 $5,460 $2,509 $27,069 Charge-offs (5,816 ) — (759 ) (6,575 ) (200 ) (237 ) (7,012 ) Recoveries 56 — 156 212 11 74 297 Provision 6,591 (563 ) (607 ) 5,421 (19 ) 248 5,650 Ending Balance $9,971 $1,195 $6,992 $18,158 $5,252 $2,594 $26,004 (1) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2015 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Unallocated Total Beginning Balance $8,202 $1,300 $7,987 $17,489 $5,430 $2,713 $2,391 $28,023 Charge-offs (809 ) — (671 ) (1,480 ) (207 ) (618 ) — (2,305 ) Recoveries 92 — 87 179 28 94 — 301 Provision 1,655 458 799 2,912 209 320 (2,391 ) 1,050 Ending Balance $9,140 $1,758 $8,202 $19,100 $5,460 $2,509 $— $27,069 (1) Commercial & industrial loans. The following table presents the activity in the allowance for loan losses for the year ended December 31, 2014 : (Dollars in thousands) Commercial Mortgages Construction C&I (1) Total Commercial Residential Consumer Unallocated Total Beginning Balance $8,022 $383 $7,835 $16,240 $6,450 $2,511 $2,685 $27,886 Charge-offs (977 ) — (558 ) (1,535 ) (132 ) (282 ) — (1,949 ) Recoveries 24 — 86 110 51 75 — 236 Provision 1,133 917 624 2,674 (939 ) 409 (294 ) 1,850 Ending Balance $8,202 $1,300 $7,987 $17,489 $5,430 $2,713 $2,391 $28,023 (1) 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) December 31, 2016 December 31, 2015 Related Allowance Related Allowance Loans Loans Loans Individually Evaluated For Impairment: Commercial: Mortgages $9,776 $448 $15,141 $1,633 Construction & development — — — — Commercial & industrial 7,098 3 3,871 771 Residential Real Estate 15,661 151 11,333 156 Consumer 1,280 4 1,881 23 Subtotal 33,815 606 32,226 2,583 Loans Collectively Evaluated For Impairment: Commercial: Mortgages 1,064,410 9,523 916,812 7,507 Construction & development 121,371 1,195 122,297 1,758 Commercial & industrial 569,011 6,989 596,426 7,431 Residential Real Estate 1,107,087 5,101 1,002,222 5,304 Consumer 338,677 2,590 343,144 2,486 Subtotal 3,200,556 25,398 2,980,901 24,486 Total $3,234,371 $26,004 $3,013,127 $27,069

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Summary of Premises and Equipment	The following presents a summary of premises and equipment: (Dollars in thousands) December 31, 2016 2015 Land and improvements $6,020 $6,020 Premises and improvements 37,913 36,358 Furniture, fixtures and equipment 28,383 27,420 Total premises and equipment 72,316 69,798 Less accumulated depreciation 43,296 40,205 Total premises and equipment, net $29,020 $29,593

Goodwill and Other Intangibles

Goodwill and Other Intangibles (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Carrying Value of Goodwill	The following table presents the carrying value of goodwill at the reporting unit (or business segment) level: (Dollars in thousands) December 31, 2016 December 31, 2015 Commercial Banking Segment $22,591 $22,591 Wealth Management Services Segment 41,468 41,468 Total $64,059 $64,059
Schedule of Carrying Value of Other Intangible Assets	The following table presents the components of intangible assets: (Dollars in thousands) December 31, 2016 December 31, 2015 Advisory Contracts Non-compete Agreements Advisory Contracts Non-compete Agreements Gross carrying amount $20,803 $369 $20,803 $369 Accumulated amortization 10,648 349 9,610 102 Net amount $10,155 $20 $11,193 $267
Schedule of Estimated Annual Amortization Expense	The following table presents estimated annual amortization expense for intangible assets at December 31, 2016 : (Dollars in thousands) Advisory Contracts Non-compete Agreements Total Years ending December 31, 2017 $1,014 $20 $1,034 2018 979 — 979 2019 943 — 943 2020 914 — 914 2021 891 — 891 2022 and thereafter 5,414 — 5,414

Income Tax Expense (Tables)

Income Tax Expense (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense	The following table presents the components of income tax expense: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Current tax expense: Federal $19,444 $17,864 $16,286 State 2,061 1,194 866 Total current tax expense 21,505 19,058 17,152 Deferred tax expense (benefit): Federal 796 2,003 1,820 State 72 (183 ) 27 Total deferred tax expense 868 1,820 1,847 Total income tax expense $22,373 $20,878 $18,999
Schedule of Effective Income Tax Rate Reconciliation	Total income tax expense varies from the amount determined by applying the Federal income tax rate to income before income taxes. The following table presents the reasons for the differences: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Tax expense at Federal statutory rate $24,099 $22,520 $20,938 (Decrease) increase in taxes resulting from: Tax-exempt income (1,599 ) (1,604 ) (1,540 ) Dividends received deduction (58 ) (57 ) (29 ) BOLI (930 ) (694 ) (646 ) Federal tax credits (364 ) (364 ) (364 ) Change in fair value of contingent consideration (314 ) — — Acquisition related expenses — 318 — State income tax expense, net of federal income tax benefit 1,387 658 581 Other 152 101 59 Total income tax expense $22,373 $20,878 $18,999
Schedule of Deferred Tax Assets and Liabilities	The following table presents the approximate tax effects of temporary differences that give rise to deferred tax assets and deferred tax liabilities: (Dollars in thousands) December 31, 2016 2015 Deferred tax assets: Allowance for loan losses $9,621 $10,015 Defined benefit pension obligations 3,804 3,447 Deferred compensation 3,991 3,181 Deferred loan origination fees 1,999 2,001 Stock based compensation 1,519 1,772 Net unrealized losses on securities available for sale 4,008 — Other 3,495 3,547 Deferred tax assets 28,437 23,963 Deferred tax liabilities: Net unrealized gains on securities available for sale — (617 ) Amortization of intangibles (3,765 ) (4,240 ) Deferred loan origination costs (5,156 ) (5,089 ) Loan servicing rights (1,293 ) (1,238 ) Other (1,419 ) (1,009 ) Deferred tax liabilities (11,633 ) (12,193 ) Net deferred tax asset $16,804 $11,770

Time Certificates of Deposit (T

Time Certificates of Deposit (Tables)	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Schedule of Time Certificates of Deposit Maturities	The following table presents scheduled maturities of time certificates of deposit: (Dollars in thousands) Scheduled Maturity Weighted Average Rate Years ending December 31: 2017 $409,292 0.73 % 2018 188,978 1.12 2019 216,245 1.54 2020 85,922 1.61 2021 60,752 1.77 2022 and thereafter 424 1.89 Balance at December 31, 2016 $961,613 1.13 %
Schedule of Time Certificates of Deposit $100 Thousand or More Maturities	The following table presents the amount of time certificates of deposit in denominations of $100 thousand or more at December 31, 2016 , maturing during the periods indicated: (Dollars in thousands) January 1, 2017 to March 31, 2017 $82,626 April 1, 2017 to June 30, 2017 33,443 July 1, 2017 to December 31, 2017 35,301 January 1, 201 and beyond 126,372 Balance at December 31, 2016 $277,742

Borrowings (Tables)

Borrowings (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
FHLBB Advances Maturity Summary	The following table presents scheduled maturities and weighted average interest rates on FHLBB advances outstanding as of December 31, 2016 : (Dollars in thousands) Scheduled Maturity Weighted Average Rate 2017 $420,075 0.89 % 2018 98,134 1.36 2019 137,258 1.65 2020 72,033 1.95 2021 51,222 2.50 2022 and thereafter 70,208 3.81 Total $848,930 1.49 %
Schedule of Short-Term FHLBB Advances	The following table presents certain information concerning short-term FHLBB advances: (Dollars in thousands) As of and for the years ended December 31, 2016 2015 2014 Average amount outstanding during the period $275,533 $155,874 $70,693 Amount outstanding at end of period $352,500 $107,500 $200,000 Highest month end balance during period $367,500 $229,500 $200,000 Weighted-average interest rate at end of period 0.79 % 0.55 % 0.37 % Weighted-average interest rate during the period 0.73 % 0.38 % 0.35 %

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Regulatory Capital Requirements	The following table presents the Corporation’s and the Bank’s actual capital amounts and ratios, as well as the corresponding minimum and well capitalized regulatory amounts and ratios that were in effect during the respective periods: (Dollars in thousands) Actual For Capital Adequacy Purposes To Be “Well Capitalized” Under Prompt Corrective Action Regulations Amount Ratio Amount Ratio Amount Ratio December 31, 2016 Total Capital (to Risk-Weighted Assets): Corporation $390,867 12.26 % $255,093 8.00 % N/A N/A Bank 389,840 12.23 255,050 8.00 318,813 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 364,655 11.44 191,320 6.00 N/A N/A Bank 363,628 11.41 191,288 6.00 255,050 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 342,656 10.75 143,490 4.50 N/A N/A Bank 363,628 11.41 143,466 4.50 207,228 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 364,655 8.67 168,271 4.00 N/A N/A Bank 363,628 8.65 168,207 4.00 210,259 5.00 December 31, 2015 Total Capital (to Risk-Weighted Assets): Corporation 367,443 12.58 233,739 8.00 N/A N/A Bank 366,676 12.55 233,676 8.00 292,095 10.00 Tier 1 Capital (to Risk-Weighted Assets): Corporation 340,130 11.64 175,304 6.00 N/A N/A Bank 339,363 11.62 175,257 6.00 233,676 8.00 Common Equity Tier 1 Capital (to Risk-Weighted Assets): Corporation 318,131 10.89 131,478 4.50 N/A N/A Bank 339,363 11.62 131,443 4.50 189,861 6.50 Tier 1 Capital (to Average Assets): (1) Corporation 340,130 9.37 145,191 4.00 N/A N/A Bank 339,363 9.36 145,103 4.00 181,378 5.00 (1) Leverage ratio.

Derivative Financial Instrume44

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivatives by Balance Sheet Location	The following table presents the fair values of derivative instruments in the Corporation’s Consolidated Balance Sheets: (Dollars in thousands) Asset Derivatives Liability Derivatives Fair Value Fair Value December 31, Balance Sheet Location 2016 2015 Balance Sheet Location 2016 2015 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate swaps Other assets $— $— Other liabilities $378 $— Interest rate caps Other assets 134 187 Other liabilities — — Derivatives not Designated as Hedging Instruments: Forward loan commitments: Interest rate lock commitments Other assets 1,133 1,220 Other liabilities 88 — Commitments to sell mortgage loans Other assets 279 — Other liabilities 1,349 2,012 Loan related derivative contracts: Interest rate swaps with customers Other assets 2,036 8,027 Other liabilities — — Mirror swaps with counterparties Other assets — — Other liabilities 2,228 8,266 Risk participation agreements Other assets — 56 Other liabilities — 69 Total $3,582 $9,490 $4,043 $10,347
Derivative Instruments Effect in Statements of Income and Changes in Shareholders' Equity	The following tables present the effect of derivative instruments in the Corporations’ Consolidated Statements of Income and Changes in Shareholders’ Equity: (Dollars in thousands) Gain (Loss) Recognized in Other Comprehensive Income, Net of Tax (Effective Portion) Location of Gain (Loss) Recognized in Income (Ineffective Portion and Amount Excluded from Effectiveness Testing) Gain (Loss) Recognized in Income (Ineffective Portion) Years ended December 31, 2016 2015 2014 2016 2015 2014 Derivatives Designated as Cash Flow Hedging Instruments: Interest rate risk management contracts: Interest rate swaps ($224 ) $288 $331 Interest Expense $— $— $— Interest rate caps (33 ) (44 ) — Interest Expense — — — Total ($257 ) $244 $331 $— $— $— (Dollars in thousands) Amount of Gain (Loss) Recognized in Income on Derivative Years ended December 31, Statement of Income Location 2016 2015 2014 Derivatives not Designated as Hedging Instruments: Forward loan commitments: Interest rate lock commitments Mortgage banking revenues ($175 ) $28 $800 Commitments to sell mortgage loans Mortgage banking revenues 942 3 (1,442 ) Loan related derivative contracts: Interest rate swaps with customers Loan related derivative income (598 ) 7,569 4,989 Mirror swaps with counterparties Loan related derivative income 3,854 (4,904 ) (3,853 ) Risk participation agreements Loan related derivative income (13 ) (224 ) — Total $4,010 $2,472 $494

Balance Sheet Offsetting (Table

Balance Sheet Offsetting (Tables)	12 Months Ended
	Dec. 31, 2016
Balance Sheet Offsetting [Abstract]
Balance Sheet Offsetting	The following tables present the Corporation’s derivative asset and derivative liability positions and the effect of netting arrangements on the Consolidated Balance Sheets: (Dollars in thousands) Gross Derivative Positions Offsetting Derivative Positions Net Amounts Presented in Balance Sheet Cash Collateral Pledged Net Amount December 31, 2016 Derivative Assets: Interest rate risk management contracts: Interest rate caps $134 $— $134 $— $134 Loan-related derivative contracts: Interest rate swaps with customers 4,920 2,884 2,036 — 2,036 Mirror swaps with counterparties 2,758 2,758 — — — Total $7,812 $5,642 $2,170 $— $2,170 Derivative Liabilities: Interest rate risk management contracts: Interest rate swaps $378 $— $378 $133 $245 Loan-related derivative contracts: Interest rate swaps with customers 2,884 2,884 — — — Mirror swaps with counterparties 4,986 2,758 2,228 1,295 933 Total $8,248 $5,642 $2,606 $1,428 $1,178 (Dollars in thousands) Gross Derivative Positions Offsetting Derivative Positions Net Amounts Presented in Balance Sheet Cash Collateral Pledged Net Amount December 31, 2015 Derivative Assets: Interest rate risk management contracts: Interest rate caps $187 $— $187 $— $187 Loan-related derivative contracts: Interest rate swaps with customers 8,027 — 8,027 — 8,027 Mirror swaps with counterparties — — — — — Total $8,214 $— $8,214 $— $8,214 Derivative Liabilities: Loan-related derivative contracts: Interest rate swaps with customers $— $— $— $— $— Mirror swaps with counterparties 8,266 — 8,266 8,343 (77 ) Total $8,266 $— $8,266 $8,343 ($77 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Mortgage Loans Held For Sale, Interest Rate Lock Commitments and Commitments to Sell	The following table presents the changes in fair value related to mortgage loans held for sale, interest rate lock commitments and commitments to sell residential real estate mortgage loans, for which the fair value option was elected. Changes in fair values are reported as a component of mortgage banking revenues in the Consolidated Statements of Income. (Dollars in thousands) Years ended December 31, 2016 2015 2014 Mortgage loans held for sale ($691 ) ($48 ) $598 Interest rate lock commitments (175 ) 28 800 Commitments to sell 942 3 (1,442 ) Total changes in fair value $76 ($17 ) ($44 )
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present the balances of assets and liabilities reported at fair value on a recurring basis: (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2016 Assets: Securities available for sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $108,440 $— $108,440 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 588,085 — 588,085 — Obligations of states and political subdivisions 14,485 — 14,485 — Individual name issuer trust preferred debt securities 26,736 — 26,736 — Corporate bonds 2,166 — 2,166 — Mortgage loans held for sale 29,434 — 29,434 — Derivative assets 3,582 — 3,582 — Total assets at fair value on a recurring basis $772,928 $— $772,928 $— Liabilities: Derivative liabilities $4,043 $— $4,043 $— Contingent consideration liability (1) 2,047 — — 2,047 Total liabilities at fair value on a recurring basis $6,090 $— $4,043 $2,047 (1) The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets. (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2015 Assets: Securities available for sale: Obligations of U.S. government agencies and U.S. government-sponsored enterprises $77,015 $— $77,015 $— Mortgage-backed securities issued by U.S. government agencies and U.S. government-sponsored enterprises 234,856 — 234,856 — Obligations of states and political subdivisions 36,080 — 36,080 — Individual name issuer trust preferred debt securities 25,138 — 25,138 — Corporate bonds 1,955 — 1,955 — Mortgage loans held for sale 33,969 — 33,969 — Derivative assets 9,490 — 9,490 — Total assets at fair value on a recurring basis $418,503 $— $418,503 $— Liabilities: Derivative liabilities $10,347 $— $10,347 $— Contingent consideration liability (1) 2,945 — — 2,945 Total liabilities at fair value on a recurring basis $13,292 $— $10,347 $2,945 (1) The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets.
Fair value of Contingent Consideration Rollforward	The following table presents the change in the contingent consideration liability, a Level 3 liability measured at fair value on a recurring basis: (Dollars in thousands) Years ended December 31, 2016 2015 Beginning Balance $2,945 $— Initial recognition — 2,904 Change in fair value (898 ) 41 Payments — — Ending Balance $2,047 $2,945
Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis	The following table presents the carrying value of assets held at December 31, 2016 , which were written down to fair value during the year ended December 31, 2016 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $3,828 $— $— $3,828 Property acquired through foreclosure or repossession 605 — — 605 Total assets at fair value on a nonrecurring basis $4,433 $— $— $4,433 The allowance for loan losses on the collateral dependent impaired loans amounted to $469 thousand at December 31, 2016 . The following table summarizes the carrying value of assets held at December 31, 2015 , which were written down to fair value during the year ended December 31, 2015 : (Dollars in thousands) Total Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Assets: Collateral dependent impaired loans $10,545 $— $— $10,545 Property acquired through foreclosure or repossession 270 — — 270 Total assets at fair value on a nonrecurring basis $10,815 $— $— $10,815 The allowance for loan losses on the collateral dependent impaired loans amounted to $2.4 million at December 31, 2015 .
Qualitative Information About Level 3 Assets Measured at Fair Value on a Nonrecurring Basis	The following tables present valuation techniques and unobservable inputs for assets measured at fair value on a nonrecurring basis for which the Corporation has utilized Level 3 inputs to determine fair value: (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Range of Inputs Utilized (Weighted Average) December 31, 2016 Collateral dependent impaired loans $3,828 Appraisals of collateral Discount for costs to sell 10% - 20% (15%) Appraisal adjustments (1) 0% - 10% (9%) Property acquired through foreclosure or repossession 605 Appraisals of collateral Discount for costs to sell 10% - 12% (11%) Appraisal adjustments (1) 6% - 50% (24%) (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, 2015 Collateral dependent impaired loans $10,545 Appraisals of collateral Discount for costs to sell 0% - 20% (2%) Property acquired through foreclosure or repossession 270 Appraisals of collateral Discount for costs to sell 12% Appraisal adjustments (1) 32% (1) Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property.
Carrying Amounts, Estimated Fair Values and Fair Value Hierarchy of Financial Instruments	The following tables present the carrying amount, estimated fair value and placement in the fair value hierarchy of the Corporation’s financial instruments. The tables exclude financial instruments for which the carrying value approximates fair value. Financial assets for which the fair value approximates carrying value include cash and cash equivalents, FHLBB stock, accrued interest receivable and bank-owned life insurance. Financial liabilities for which the fair value approximates carrying value include non-maturity deposits and accrued interest payable. (Dollars in thousands) Carrying Amount Total Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2016 Financial Assets: Securities held to maturity $15,633 $15,920 $— $15,920 $— Loans, net of allowance for loan losses 3,208,367 3,218,651 — — 3,218,651 Financial Liabilities: Time deposits $961,613 $962,374 $— $962,374 $— FHLBB advances 848,930 852,888 — 852,888 — Junior subordinated debentures 22,681 16,970 — 16,970 — (Dollars in thousands) Carrying Amount Estimated Fair Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs Significant Unobservable Inputs (Level 3) December 31, 2015 Financial Assets: Securities held to maturity $20,023 $20,516 $— $20,516 $— Loans, net of allowance for loan losses 2,986,058 3,004,782 — — 3,004,782 Financial Liabilities: Time deposits $833,898 $834,574 $— $834,574 $— FHLBB advances 378,973 388,275 — 388,275 — Junior subordinated debentures 22,681 16,468 — 16,468 —

Employee Benefits (Tables)

Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Schedule of Projected Benefit Obligations, Fair Value of Plan Assets and Funded (Unfunded) Status	The following table presents the plans’ projected benefit obligations, fair value of plan assets and funded (unfunded)status: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2016 2015 2016 2015 Change in Benefit Obligation: Benefit obligation at beginning of period $67,550 $73,149 $13,015 $13,097 Service cost 2,148 2,459 122 78 Interest cost 2,576 2,928 432 490 Actuarial (gain) loss 3,888 (5,410 ) 374 88 Benefits paid (3,072 ) (5,430 ) (789 ) (738 ) Administrative expenses (139 ) (146 ) — — Benefit obligation at end of period 72,951 67,550 13,154 13,015 Change in Plan Assets: Fair value of plan assets at beginning of period 65,710 67,613 — — Actual return on plan assets 4,788 673 — — Employer contributions 8,500 3,000 789 738 Benefits paid (3,072 ) (5,430 ) (789 ) (738 ) Administrative expenses (139 ) (146 ) — — Fair value of plan assets at end of period 75,787 65,710 — — Funded (unfunded) status at end of period $2,836 ($1,840 ) ($13,154 ) ($13,015 )
Schedule of Components of Accumulated Other Comprehensive Income (Loss) Related to Retirements Plans	The following table presents components of accumulated other comprehensive income related to the qualified pension plan and non-qualified retirement plans, on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans At December 31, 2016 2015 2016 2015 Net actuarial loss $15,593 $12,688 $4,519 $4,392 Prior service credit (62 ) (84 ) (1 ) (2 ) Total pre-tax amounts recognized in accumulated other comprehensive income $15,531 $12,604 $4,518 $4,390
Schedule of Net Periodic Benefit Costs and Other Amounts Recognized in Other Comprehensive Income (Loss)	The following table presents components of net periodic benefit cost and other amounts recognized in other comprehensive income (loss), on a pre-tax basis: (Dollars in thousands) Qualified Pension Plan Non-Qualified Retirement Plans Years ended December 31, 2016 2015 2014 2016 2015 2014 Net Periodic Benefit Cost: Service cost $2,148 $2,459 $2,152 $122 $78 $46 Interest cost 2,576 2,928 2,891 432 490 478 Expected return on plan assets (4,633 ) (4,515 ) (4,063 ) — — — Amortization of prior service credit (23 ) (23 ) (23 ) (1 ) (1 ) (1 ) Recognized net actuarial loss 828 1,249 461 247 245 70 Net periodic benefit cost 896 2,098 1,418 800 812 593 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (on a pre-tax basis): Net (gain) loss 2,904 (2,816 ) 10,993 127 (156 ) 2,476 Prior service cost 23 23 23 1 1 1 Recognized in other comprehensive (loss) income 2,927 (2,793 ) 11,016 128 (155 ) 2,477 Total recognized in net periodic benefit cost and other comprehensive (loss) income $3,823 ($695 ) $12,434 $928 $657 $3,070
Schedule of Assumptions Used for Net Periodic Benefit Cost	The following table presents the measurement date and weighted-average assumptions used to determine benefit obligations at December 31, 2016 and 2015 : Qualified Pension Plan Non-Qualified Retirement Plans 2016 2015 2016 2015 Measurement date Dec 31, 2016 Dec 31, 2015 Dec 31, 2016 Dec 31, 2015 Discount rate 4.18% 4.48% 4.00% 4.20% Rate of compensation increase 3.75 3.75 3.75 3.75 The following table presents the measurement date and weighted-average assumptions used to determine net periodic benefit cost for the years ended December 31, 2016 , 2015 and 2014 : Qualified Pension Plan Non-Qualified Retirement Plans 2016 2015 2014 2016 2015 2014 Measurement date Dec 31, 2015 Dec 31, 2014 Dec 31, 2013 Dec 31, 2015 Dec 31, 2014 Dec 31, 2013 Discount rate N/A 4.125% 4.875% N/A 3.90% 4.60% Equivalent single discount rate for benefit obligations 4.48% N/A N/A 4.20% N/A N/A Equivalent single discount rate for service cost 4.63 N/A N/A 4.59 N/A N/A Equivalent single discount rate for interest cost 3.88 N/A N/A 3.44 N/A N/A Expected long-term return on plan assets 6.75 7.25 7.25 N/A N/A N/A Rate of compensation increase 3.75 3.75 3.75 3.75 3.75 3.75
Schedule of Fair Value and Allocation of Plan Assets	The following table present the asset allocations of the qualified pension plan, by asset category: December 31, 2016 2015 Asset Category: Equity securities 63.8 % 63.4 % Fixed income securities 32.4 34.6 Cash and cash equivalents 3.8 2.0 Total 100.0 % 100.0 % The following tables present the fair values of the qualified pension plan’s assets: (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2016 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $2,880 $— $— $2,880 Obligations of U.S. government agencies and U.S. government-sponsored enterprises — 4,233 — 4,233 Obligations of states and political subdivisions — 3,418 — 3,418 Corporate bonds — 13,775 — 13,775 Common stocks 33,893 — — 33,893 Mutual funds 17,588 — — 17,588 Total plan assets $54,361 $21,426 $— $75,787 (Dollars in thousands) Fair Value Measurements Using Assets at Fair Value December 31, 2015 Level 1 Level 2 Level 3 Assets: Cash and cash equivalents $1,598 $— $— $1,598 Obligations of U.S. government agencies and U.S. government-sponsored enterprises — 3,306 — 3,306 Obligations of states and political subdivisions — 3,438 — 3,438 Corporate bonds — 12,955 — 12,955 Common stocks 29,433 — — 29,433 Mutual funds 14,980 — — 14,980 Total plan assets $46,011 $19,699 $— $65,710
Schedule of Expected Future Benefit Payments	The following table presents the benefit payments, which reflect expected future service, as appropriate, expected to be paid: (Dollars in thousands) Qualified Pension Plan Non-Qualified Plans 2017 $3,709 $779 2018 3,064 772 2019 3,169 801 2020 3,991 895 2021 3,682 881 Years 2022 - 2026 24,864 4,248

Share-Based Compensation Arra48

Share-Based Compensation Arrangements (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation Cost for Share-based Compensation Arrangements	The following table presents share-based compensation expense and the related income tax benefit recognized in the Consolidated Statements of Income for stock options, nonvested share awards and nonvested performance shares: (Dollars in thousands) Years ended December 31, 2016 2015 2014 Share-based compensation expense $2,190 $2,074 $1,880 Related income tax benefit $810 $767 $676
Stock Options Fair Value Assumptions	The following presents the assumptions used in determining the grant date fair value of the stock option awards granted to certain key employees: 2016 2015 2014 Options granted 53,400 48,600 25,850 Cliff vesting period (years) 3 3-5 3 Expected term (years) 7.5 7.5 8 Expected dividend yield 3.89 % 3.94 % 3.83 % Weighted average expected volatility 29.99 % 40.76 % 41.84 % Weighted average risk-free interest rate 1.66 % 1.95 % 2.27 % Weighted average grant-date fair value $7.92 $11.15 $9.92
Stock Options Activity	The following table presents a summary of the status of Washington Trust’s stock options outstanding as of and for the year ended December 31, 2016 : Number of Stock Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term (Years) Aggregate Intrinsic Value (000’s) Beginning of period 309,116 $26.84 Granted 53,400 40.25 Exercised (143,237 ) 22.87 Forfeited or expired — — End of period 219,279 $32.70 7.17 $5,121 At end of period: Options exercisable 89,954 $25.34 4.77 $2,763 Options expected to vest in future periods 129,325 $37.82 8.85 $2,358
Schedule of Stock Options Outstanding and Options Exercisable	The following table presents additional information concerning options outstanding and options exercisable at December 31, 2016 : Options Outstanding Options Exercisable Exercise Price Ranges Number of Shares Weighted Average Remaining Life (Years) Weighted Average Exercise Price Number of Shares Weighted Average Exercise Price $15.01 to $20.00 13,200 2.93 $17.52 13,200 $17.52 $20.01 to $25.00 54,090 4.52 23.08 47,090 22.84 $25.01 to $30.00 — — — — — $30.01 to $35.00 51,689 6.90 32.76 29,564 32.77 $35.01 to $40.00 46,900 8.74 39.39 100 39.55 $40.01 to $45.00 53,400 9.80 40.25 — — 219,279 7.17 $32.70 89,954 $25.34
Nonvested Shares Activity	The following table presents a summary of the status of Washington Trust’s nonvested shares as of and for the year ended December 31, 2016 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 47,225 $33.46 Granted 22,175 38.82 Vested (16,797 ) 29.24 Forfeited (2,928 ) 36.11 End of period 49,675 $37.12
Nonvested Performance Shares Outstanding	The following table presents a summary of the performance share awards as of December 31, 2016 : Grant Date Fair Value per Share Current Performance Assumption Expected Number of Shares Performance shares awarded in: 2016 $36.11 140% 47,532 2015 38.02 142% 37,683 2014 34.66 133% 16,783 Total 101,998
Nonvested Performance Shares Activity	The following table presents a summary of the status of Washington Trust’s performance share awards as of and for the year ended December 31, 2016 : Number of Shares Weighted Average Grant Date Fair Value Beginning of period 110,891 $32.81 Granted 47,532 36.11 Vested (48,090 ) 27.30 Forfeited (8,335 ) 37.26 End of period 101,998 $36.58

Business Segments (Tables)

Business Segments (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Statement of Operations and Total Assets by Reportable Segment	The following tables present the statement of operations and total assets for Washington Trust’s reportable segments: (Dollars in thousands) Year ended December 31, 2016 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $91,221 ($66 ) $19,323 $110,478 Provision for loan losses 5,650 — — 5,650 Net interest income (expense) after provision for loan losses 85,571 (66 ) 19,323 104,828 Noninterest income 24,783 37,569 2,777 65,129 Noninterest expenses: Depreciation and amortization expense 2,771 1,940 224 4,935 Other noninterest expenses 58,452 25,239 12,477 96,168 Total noninterest expenses 61,223 27,179 12,701 101,103 Income before income taxes 49,131 10,324 9,399 68,854 Income tax expense 16,790 3,692 1,891 22,373 Net income $32,341 $6,632 $7,508 $46,481 Total assets at period end $3,354,633 $64,625 $961,857 $4,381,115 Expenditures for long-lived assets 2,267 464 381 3,112 (Dollars in thousands) Year ended December 31, 2015 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income (expense) $84,757 ($47 ) $19,272 $103,982 Provision for loan losses 1,050 — — 1,050 Net interest income (expense) after provision for loan losses 83,707 (47 ) 19,272 102,932 Noninterest income 20,618 35,416 2,306 58,340 Noninterest expenses: Depreciation and amortization expense 2,584 1,488 213 4,285 Other noninterest expenses 55,203 25,632 11,809 92,644 Total noninterest expenses 57,787 27,120 12,022 96,929 Income before income taxes 46,538 8,249 9,556 64,343 Income tax expense 15,330 3,475 2,073 20,878 Net income $31,208 $4,774 $7,483 $43,465 Total assets at period end $3,152,231 $63,801 $555,572 $3,771,604 Expenditures for long-lived assets 4,714 411 354 5,479 (Dollars in thousands) Year ended December 31, 2014 Commercial Banking Wealth Management Services Corporate Consolidated Total Net interest income $80,500 ($24 ) $19,029 $99,505 Provision for loan losses 1,850 — — 1,850 Net interest income (expense) after provision for loan losses 78,650 (24 ) 19,029 97,655 Noninterest income 17,575 33,378 8,062 59,015 Noninterest expenses: Depreciation and amortization expense 2,447 1,127 203 3,777 Other noninterest expenses 52,639 22,386 18,045 93,070 Total noninterest expenses 55,086 23,513 18,248 96,847 Income before income taxes 41,139 9,841 8,843 59,823 Income tax expense 13,497 3,724 1,778 18,999 Net income $27,642 $6,117 $7,065 $40,824 Total assets at period end $2,986,453 $52,720 $547,701 $3,586,874 Expenditures for long-lived assets 3,474 1,578 174 5,226

Other Comprehensive Income (L50

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Activity in Other Comprehensive Income (Loss)	The following tables present the activity in other comprehensive income (loss): (Dollars in thousands) Year ended December 31, 2016 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale ($12,502 ) ($4,626 ) ($7,876 ) Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale ($12,502 ) ($4,626 ) ($7,876 ) Cash flow hedges: Changes in fair value of cash flow hedges (403 ) (146 ) (257 ) Net cash flow hedge losses reclassified into earnings — — — Net change in the fair value of cash flow hedges (403 ) (146 ) (257 ) Defined benefit plan obligations: Defined benefit plan obligation adjustment (4,106 ) (1,518 ) (2,588 ) Amortization of net actuarial losses (1) 1,075 397 678 Amortization of net prior service credits (1) (24 ) (9 ) (15 ) Net change in defined benefit plan obligations (3,055 ) (1,130 ) (1,925 ) Total other comprehensive loss ($15,960 ) ($5,902 ) ($10,058 ) (1) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2015 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale ($4,926 ) ($1,755 ) ($3,171 ) Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale ($4,926 ) ($1,755 ) ($3,171 ) Cash flow hedges: Changes in fair value of cash flow hedges (102 ) (49 ) (53 ) Net cash flow hedge losses reclassified into earnings (1) 469 172 297 Net change in the fair value of cash flow hedges 367 123 244 Defined benefit plan obligations: Defined benefit plan obligation adjustment 1,478 376 1,102 Amortization of net actuarial losses (2) 1,494 542 952 Amortization of net prior service credits (2) (24 ) (7 ) (17 ) Net change in defined benefit plan obligations 2,948 911 2,037 Total other comprehensive loss ($1,611 ) ($721 ) ($890 ) (1) The pre-tax amount is included in interest expense on junior subordinated debentures in the Consolidated Statements of Income. (2) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income. (Dollars in thousands) Year ended December 31, 2014 Pre-tax Amounts Income Taxes Net of Tax Securities available for sale: Changes in fair value of securities available for sale $1,601 $580 $1,021 Net (gains) losses on securities classified into noninterest income — — — Net change in fair value of securities available for sale 1,601 580 1,021 Cash flow hedges: Changes in fair value of cash flow hedges (56 ) (18 ) (38 ) Net cash flow hedge losses reclassified into earnings (1) 577 208 369 Net change in the fair value of cash flow hedges 521 190 331 Defined benefit plan obligations: Defined benefit plan obligation adjustment (14,000 ) (5,067 ) (8,933 ) Amortization of net actuarial losses (2) 531 190 341 Amortization of net prior service credits (2) (24 ) (8 ) (16 ) Net change in defined benefit plan obligations (13,493 ) (4,885 ) (8,608 ) Total other comprehensive loss ($11,371 ) ($4,115 ) ($7,256 ) (1) The pre-tax amount is included in interest expense on junior subordinated debentures in the Consolidated Statements of Income. (2) The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income.
Changes in Components of Accumulated Other Comprehensive Income (Loss)	The following tables present the changes in accumulated other comprehensive income (loss) by component, net of tax: (Dollars in thousands) Net Unrealized Losses on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2015 $1,051 ($43 ) ($10,707 ) ($9,699 ) Other comprehensive loss before reclassifications (7,876 ) (257 ) (2,588 ) (10,721 ) Amounts reclassified from accumulated other comprehensive income — — 663 663 Net other comprehensive loss income (7,876 ) (257 ) (1,925 ) (10,058 ) Balance at December 31, 2016 ($6,825 ) ($300 ) ($12,632 ) ($19,757 ) (Dollars in thousands) Net Unrealized Gains on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2014 $4,222 ($287 ) ($12,744 ) ($8,809 ) Other comprehensive (loss) income before reclassifications (3,171 ) (53 ) 1,102 (2,122 ) Amounts reclassified from accumulated other comprehensive income — 297 935 1,232 Net other comprehensive (loss) income (3,171 ) 244 2,037 (890 ) Balance at December 31, 2015 $1,051 ($43 ) ($10,707 ) ($9,699 ) (Dollars in thousands) Net Unrealized Gains on Available For Sale Securities Net Unrealized Losses on Cash Flow Hedges Pension Benefit Adjustment Total Balance at December 31, 2013 $3,201 ($618 ) ($4,136 ) ($1,553 ) Other comprehensive income (loss) before reclassifications 1,021 (38 ) (8,933 ) (7,950 ) Amounts reclassified from accumulated other comprehensive income — 369 325 694 Net other comprehensive income (loss) 1,021 331 (8,608 ) (7,256 ) Balance at December 31, 2014 $4,222 ($287 ) ($12,744 ) ($8,809 )

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Calculation of Earnings Per Common Share	The following table presents the calculation of earnings per common share: (Dollars and shares in thousands, except per share amounts) Years ended December 31, 2016 2015 2014 Earnings per common share - basic: Net income $46,481 $43,465 $40,824 Less dividends and undistributed earnings allocated to participating securities (97 ) (126 ) (152 ) Net income applicable to common shareholders 46,384 43,339 40,672 Weighted average common shares 17,081 16,879 16,689 Earnings per common share - basic $2.72 $2.57 $2.44 Earnings per common share - diluted: Net income $46,481 $43,465 $40,824 Less dividends and undistributed earnings allocated to participating securities (97 ) (126 ) (151 ) Net income applicable to common shareholders 46,384 43,339 40,673 Weighted average common shares 17,081 16,879 16,689 Dilutive effect of common stock equivalents 127 188 183 Weighted average diluted common shares 17,208 17,067 16,872 Earnings per common share - diluted $2.70 $2.54 $2.41

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Financial Instruments with Off Balance Sheet Risk	The following table presents the contractual and notional amounts of financial instruments with off-balance sheet risk: (Dollars in thousands) December 31, 2016 2015 Financial instruments whose contract amounts represent credit risk: Commitments to extend credit: Commercial loans $430,710 $360,795 Home equity lines 232,375 219,427 Other loans 49,708 44,164 Standby letters of credit 6,250 5,629 Financial instruments whose notional amounts exceed the amount of credit risk: Forward loan commitments: Interest rate lock commitments 49,502 49,712 Commitments to sell mortgage loans 78,896 87,498 Loan related derivative contracts: Interest rate swaps with customers 428,723 302,142 Mirror swaps with counterparties 428,723 302,142 Risk participation-in agreements 28,460 21,474 Interest rate risk management contracts: Interest rate swaps 60,000 —
Schedule of Future Minimum Annual Lease Payments	The following table presents the minimum annual lease payments under the terms of these leases, exclusive of renewal provisions: (Dollars in thousands) Years ending December 31: 2017 $3,448 2018 3,163 2019 2,889 2020 2,210 2021 1,914 2022 and thereafter 25,148 Total minimum lease payments $38,772

Parent Company Financial Stat53

Parent Company Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Only Balance Sheet	The following tables present parent company only financial statements of the Bancorp, reflecting the investment in the Bank on the equity basis of accounting. The Statements of Changes in Shareholders’ Equity for the parent company only are identical to the Consolidated Statements of Changes in Shareholders’ Equity and are therefore not presented. Balance Sheets (Dollars in thousands, except par value) December 31, 2016 2015 Assets: Cash on deposit with bank subsidiary $1,743 $3,169 Interest-bearing balances due from banks — — Investment in subsidiaries at equity value 413,613 398,520 Dividends receivable from subsidiaries 6,518 5,082 Other assets 332 377 Total assets $422,206 $407,148 Liabilities: Junior subordinated debentures $22,681 $22,681 Dividends payable 6,628 6,075 Contingent consideration liability 2,047 2,945 Other liabilities 46 59 Total liabilities 31,402 31,760 Shareholders’ Equity: Common stock of $.0625 par value; authorized 60,000,000 shares at December 31, 2016 and 30,000,000 at December 31, 2015; issued and outstanding 17,170,820 shares at December 31, 2016 and 17,019,578 shares at December 31, 2015 1,073 1,064 Paid-in capital 115,123 110,949 Retained earnings 294,365 273,074 Accumulated other comprehensive loss (19,757 ) (9,699 ) Total shareholders’ equity 390,804 375,388 Total liabilities and shareholders’ equity $422,206 $407,148
Parent Company Only Income Statement	Statements of Income (Dollars in thousands) Years ended December 31, 2016 2015 2014 Income: Dividends from subsidiaries $24,542 $23,399 $20,116 Other income 15 13 13 Total income 24,557 23,412 20,129 Expenses: Interest on junior subordinated debentures 491 871 964 Legal and professional fees 98 134 96 Acquisition related expenses — 308 — Change in fair value of contingent consideration (898 ) 41 — Other 282 254 253 Total expenses (27 ) 1,608 1,313 Income before income taxes 24,584 21,804 18,816 Income tax (expense) benefit (15 ) 557 454 Income before equity in undistributed earnings of subsidiaries 24,569 22,361 19,270 Equity in undistributed earnings of subsidiaries 21,912 21,104 21,554 Net income $46,481 $43,465 $40,824
Parent Company Only Cash Flow Statement	Statements of Cash Flows (Dollars in thousands) Years ended December 31, 2016 2015 2014 Cash flow from operating activities: Net income $46,481 $43,465 $40,824 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed earnings of subsidiary (21,912 ) (21,104 ) (21,554 ) (Increase) decrease in dividend receivable (1,436 ) 19 (495 ) Decrease (increase) in other assets 45 (67 ) 183 (Decrease) increase in accrued expenses and other liabilities (12 ) 2,425 (516 ) Change in fair value of contingent consideration liability (898 ) 41 — Other, net (1,051 ) (3,363 ) (245 ) Net cash provided by operating activities 21,217 21,416 18,197 Cash flows from investing activities: Cash used in business combination, net of cash acquired — (1,671 ) — Net cash used in investing activities — (1,671 ) — Cash flows from financing activities: Proceeds from stock option exercises and issuance of other equity instruments 978 1,563 1,189 Tax benefit from stock option exercises and other equity instrument issuances 1,016 694 578 Cash dividends paid (24,637 ) (22,770 ) (19,722 ) Net cash used in financing activities (22,643 ) (20,513 ) (17,955 ) Net (decrease) increase in cash (1,426 ) (768 ) 242 Cash at beginning of year 3,169 3,937 3,695 Cash at end of year $1,743 $3,169 $3,937

Selected Quarterly Consolidat54

Selected Quarterly Consolidated Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Consolidated Financial Data (Unaudited)	(Dollars and shares in thousands, except per share amounts) 2016 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $32,969 $32,190 $33,256 $35,055 Interest expense 5,234 5,414 5,877 6,467 Net interest income 27,735 26,776 27,379 28,588 Provision for loan losses 500 450 1,800 2,900 Net interest income after provision for loan losses 27,235 26,326 25,579 25,688 Noninterest income 14,634 15,914 17,261 17,320 Noninterest expense 25,450 26,030 24,650 24,973 Income before income taxes 16,419 16,210 18,190 18,035 Income tax expense 5,484 5,153 5,863 5,873 Net income $10,935 $11,057 $12,327 $12,162 Weighted average common shares outstanding - basic 17,023 17,067 17,090 17,142 Weighted average common shares outstanding - diluted 17,157 17,194 17,203 17,245 Per share information: Basic earnings per common share $0.64 $0.65 $0.72 $0.71 Diluted earnings per common share $0.64 $0.64 $0.72 $0.70 Cash dividends declared per share $0.36 $0.36 $0.37 $0.37 (Dollars and shares in thousands, except per share amounts) 2015 First Quarter Second Quarter Third Quarter Fourth Quarter Interest and dividend income $31,237 $31,510 $31,526 $31,477 Interest expense 5,535 5,482 5,529 5,222 Net interest income 25,702 26,028 25,997 26,255 Provision for loan losses — 100 200 750 Net interest income after provision for loan losses 25,702 25,928 25,797 25,505 Noninterest income 14,020 15,261 13,913 15,146 Noninterest expense 23,531 24,299 24,538 24,561 Income before income taxes 16,191 16,890 15,172 16,090 Income tax expense 5,181 5,387 4,964 5,346 Net income $11,010 $11,503 $10,208 $10,744 Weighted average common shares outstanding - basic 16,759 16,811 16,939 17,004 Weighted average common shares outstanding - diluted 16,939 16,989 17,102 17,167 Per share information: Basic earnings per common share $0.65 $0.68 $0.60 $0.63 Diluted earnings per common share $0.65 $0.68 $0.60 $0.62 Cash dividends declared per share $0.34 $0.34 $0.34 $0.34

Summary of Significant Accoun55

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Line Items]
Federal Home Loan Bank Stock, redemption period, years after membership termination	5 years
Number of days overdue to be classified as nonaccrual	90 days
Troubled debt restructured loans, management determination of loans on nonaccrual status to return to accrual status, period	6 months
Time loan is reported as TDR from date of restructuring	1 year
Equity Method Investment, Number of Investments	2
Number of low-income housing complexes included in equity method investments	2
Equity Method Investee, One [Member]
Accounting Policies [Line Items]
Equity method investment, ownership percentage	99.90%
Equity Method Investee, Two [Member]
Accounting Policies [Line Items]
Equity method investment, ownership percentage	99.90%
Premises and Improvements [Member] | Minimum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	5 years
Premises and Improvements [Member] | Maximum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	40 years
Furniture, Fixtures and Equipment [Member] | Minimum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	3 years
Furniture, Fixtures and Equipment [Member] | Maximum [Member]
Accounting Policies [Line Items]
Estimated useful life (in years)	20 years

Recently Issued Accounting Pr56

Recently Issued Accounting Pronouncements (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Average annual excess tax benefit recognized over last three years	$ 760

Acquisition (Narrative) (Detail

Acquisition (Narrative) (Details) - USD ($) $ in Thousands	Aug. 01, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Acquisition [Abstract]
Cash to acquire Halsey, gross	$ 1,700
Common stock issued for acquisition	$ 5,400	$ 0	$ 5,430	$ 0
Common stock issued for acquisition, shares	136,543
Contingent consideration liability	$ 2,904

Acquisition (Details)

Acquisition (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Aug. 01, 2015
Acquisition [Abstract]
Cash			$ 10
Deferred tax assets			653
Goodwill	$ 64,059	$ 64,059	5,945
Identifiable intangible assets			7,515
Other assets			202
Total assets acquired			14,325
Contingent consideration liability			2,904
Deferred tax liabilities			2,803
Other liabilities			1,507
Total liabilities assumed			7,214
Net assets acquired			$ 7,111

Cash and Due from Banks (Narrat

Cash and Due from Banks (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Cash and Cash Equivalents [Abstract]
Average reserve deposited with the Board of Governors of the Federal Reserve Bank	$ 11.5	$ 10.5
Interest-bearing deposits in other banks	$ 60.3	$ 48.2

Securities (Narrative) (Details

Securities (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)security	Dec. 31, 2015USD ($)security
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Securities available for sale and held to maturity pledged as collateral, fair value	$ 736.2	$ 346.1
Amortized cost of callable debt securities	155.6
Fair value of callable debt securities	$ 149.5
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	57	26
Minimum [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Callable debt securities, maturity period	2 months
Callable debt securities, call feature period	1 month
Maximum [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Callable debt securities, maturity period	20 years
Callable debt securities, call feature period	5 years
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	10	10
Number of companies issuing securities in continuous unrealized loss position | security	7
Amortized cost of trust preferred securities of individual name issuers that are below investment grade	$ 10.9
Unrealized losses of trust preferred securities of individual name issuers that are below investment grade	$ 1.3

Securities (Summary of Investme

Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	$ 750,745	$ 373,376
Available for sale securities unrealized gains	5,008	7,203
Available for sale securities unrealized losses	(15,841)	(5,535)
Available for sale, at fair value	739,912	375,044
Held to maturity securities amortized cost	15,633	20,023
Held to maturity securities unrealized gains	287	493
Held to Matruity securities unrealized losses	0	0
Held to maturity securities fair value	15,920	20,516
Total securities amortized cost	766,378	393,399
Total securities unrealized gains	5,295	7,696
Total securities unrealized losses	(15,841)	(5,535)
Total securities fair value	755,832	395,560
Available for sale securities amortized cost	750,745
Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	111,483	77,330
Available for sale securities unrealized gains	7	73
Available for sale securities unrealized losses	(3,050)	(388)
Available for sale, at fair value	108,440	77,015
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	592,833	228,908
Available for sale securities unrealized gains	4,923	6,398
Available for sale securities unrealized losses	(9,671)	(450)
Available for sale, at fair value	588,085	234,856
Held to maturity securities amortized cost	15,633	20,023
Held to maturity securities unrealized gains	287	493
Held to Matruity securities unrealized losses	0	0
Held to maturity securities fair value	15,920	20,516
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	14,423	35,353
Available for sale securities unrealized gains	62	727
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	14,485	36,080
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	29,851	29,815
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(3,115)	(4,677)
Available for sale, at fair value	26,736	25,138
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	2,155	1,970
Available for sale securities unrealized gains	16	5
Available for sale securities unrealized losses	(5)	(20)
Available for sale, at fair value	$ 2,166	$ 1,955

Securities (Securities by Contr

Securities (Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale debt securities maturities wIthin 1 year amortized cost	$ 75,499
Available for sale debt securities maturities 1-5 years amortized cost	254,974
Available for sale debt securities maturities 5-10 years amortized cost	239,622
Available for sale debt securities maturities after 10 years amortized cost	180,650
Available for sale securities amortized cost	750,745
Available for sale debt securities maturities within 1 year fair value	74,921
Available for sale debt securities maturities 1-5 years fair value	252,489
Available for sale debt securities maturities 5-10 years fair value	236,175
Available for sale debt securities maturities after 10 years fair value	176,327
Available for sale debt securities fair value	739,912
Held to maturity debt securities maturities within 1 year amortized cost	2,605
Held to maturity debt securities maturities 1-5 years amortized cost	7,157
Held to maturity debt securities maturities 5-10 years amortized cost	4,414
Held to maturity debt securities maturities after 10 years amortized cost	1,457
Held to maturity securities amortized cost	15,633	$ 20,023
Held to maturity debt securities maturities within 1 year fair value	2,653
Held to maturity debt securities maturities 1-5 years fair value	7,288
Held to maturity debt securities maturities 5-10 years fair value	4,495
Held to maturity debt securities maturities after 10 years fair value	1,484
Held to maturity securities fair value	15,920	20,516
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Held to maturity securities amortized cost	15,633	20,023
Held to maturity securities fair value	$ 15,920	$ 20,516

Securities (Securities in a Con

Securities (Securities in a Continuous Unrealized Loss Position) (Details) $ in Thousands	Dec. 31, 2016USD ($)security	Dec. 31, 2015USD ($)security
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	47	16
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 505,906	$ 97,766
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (12,726)	$ (858)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	10	10
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 26,736	$ 25,138
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (3,115)	$ (4,677)
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	57	26
Fair value of securities in a continuous unrealized loss position total	$ 532,642	$ 122,904
Unrealized losses of securities in a continuous unrealized loss position total	$ (15,841)	$ (5,535)
Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	10	4
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 98,433	$ 34,767
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (3,050)	$ (388)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	0	0
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	10	4
Fair value of securities in a continuous unrealized loss position total	$ 98,433	$ 34,767
Unrealized losses of securities in a continuous unrealized loss position total	$ (3,050)	$ (388)
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	35	9
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 407,073	$ 61,764
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (9,671)	$ (450)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	0	0
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	35	9
Fair value of securities in a continuous unrealized loss position total	$ 407,073	$ 61,764
Unrealized losses of securities in a continuous unrealized loss position total	$ (9,671)	$ (450)
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	0	0
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ 0
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ 0	$ 0
Number of securities in a continuous unrealized loss position for 12 months or longer | security	10	10
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 26,736	$ 25,138
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ (3,115)	$ (4,677)
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	10	10
Fair value of securities in a continuous unrealized loss position total	$ 26,736	$ 25,138
Unrealized losses of securities in a continuous unrealized loss position total	$ (3,115)	$ (4,677)
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Number of securities in a continuous unrealized loss position for less than 12 months | security	2	3
Fair value of securities in a continuous unrealized loss position for less than 12 months	$ 400	$ 1,235
Unrealized losses of securities in a continuous unrealized loss position for less than 12 months	$ (5)	$ (20)
Number of securities in a continuous unrealized loss position for 12 months or longer | security	0	0
Fair value of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Unrealized losses of securities in a continuous unrealized loss position for 12 months or longer	$ 0	$ 0
Number of individual name issuer trust preferred securities in a continuous unrealized loss position total | security	2	3
Fair value of securities in a continuous unrealized loss position total	$ 400	$ 1,235
Unrealized losses of securities in a continuous unrealized loss position total	$ (5)	$ (20)

Loans (Narrative) (Details)

Loans (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Net unamortized loan origination costs	$ 3,000,000	$ 2,600,000
Net unamortized premiums on purchased loans	783,000	84,000
Loans pledged as collateral	1,400,000,000	1,300,000,000
Residential loans in process of foreclosure	5,700,000	2,600,000
Interest lost on nonaccrual loans	1,600,000	1,500,000	$ 1,300,000
Interest income recognized for nonaccrual loans	640,000	522,000	$ 455,000
Nonaccrual loans	18,600,000	13,600,000
Significant commitments to lend to borrowers with nonaccrual or TDR loans	$ 0	$ 0

Loans (Narrative - Troubled Deb

Loans (Narrative - Troubled Debt Restructurings) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Recorded investment	$ 22,300	$ 18,500
Specific reserves on troubled debt restructurings	$ 567	$ 1,800

Loans (Narrative - Credit Quali

Loans (Narrative - Credit Quality Indicators) (Details) - rating	Dec. 31, 2016	Dec. 31, 2015
Receivables [Abstract]
Weighted Average Risk Rating, Commercial Loans	4.68	4.68

Loans (Summary of Loans) (Detai

Loans (Summary of Loans) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[1]	$ 3,234,371	$ 3,013,127
Percent of total loans	[1]	100.00%	100.00%
Commercial Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 1,074,186	$ 931,953
Commercial Construction & Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		121,371	122,297
Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		576,109	600,297
Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		1,094,824	984,437
Homeowner Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		27,924	29,118
Home Equity Lines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		264,200	255,565
Home Equity Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		37,272	46,649
Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		38,485	42,811
Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 1,771,666	$ 1,654,547
Percent of total loans		55.00%	55.00%
Commercial [Member] | Commercial Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[2]	$ 1,074,186	$ 931,953
Percent of total loans	[2]	33.00%	31.00%
Commercial [Member] | Commercial Construction & Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[3]	$ 121,371	$ 122,297
Percent of total loans	[3]	4.00%	4.00%
Commercial [Member] | Commercial & Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[4]	$ 576,109	$ 600,297
Percent of total loans	[4]	18.00%	20.00%
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 1,122,748	$ 1,013,555
Percent of total loans		35.00%	34.00%
Residential Real Estate [Member] | Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 1,094,824	$ 984,437
Percent of total loans		34.00%	33.00%
Residential Real Estate [Member] | Homeowner Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 27,924	$ 29,118
Percent of total loans		1.00%	1.00%
Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 339,957	$ 345,025
Percent of total loans		10.00%	11.00%
Consumer [Member] | Home Equity Lines [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 264,200	$ 255,565
Percent of total loans		8.00%	8.00%
Consumer [Member] | Home Equity Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 37,272	$ 46,649
Percent of total loans		1.00%	2.00%
Consumer [Member] | Other Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[5]	$ 38,485	$ 42,811
Percent of total loans	[5]	1.00%	1.00%
[1]	Includes net unamortized loan origination costs of $3.0 million and $2.6 million, respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand, respectively, at December 31, 2016 and 2015.
[2]	Loans primarily secured by income producing property.
[3]	Loans for construction of commercial properties, loans to developers for construction of residential properties and loans for land development.
[4]	Loans to businesses and individuals, a substantial portion of which are fully or partially collateralized by real estate.
[5]	Loans to individuals secured by general aviation aircraft and other personal installment loans.

Loans (Nonaccrual Loans) (Detai

Loans (Nonaccrual Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	$ 22,058	$ 21,047
Accruing loans 90 days or more past due	0	0
Current Payment Status [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans, current as to payment of principal and interest	3,500	7,400
Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	7,811	5,711
Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	0	0
Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	1,337	3,018
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	11,736	10,666
Homeowner Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	0	0
Home Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	0	528
Home Equity Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	1,058	1,124
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	$ 116	$ 0

Loans (Past Due Loans) (Details

Loans (Past Due Loans) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		$ 24,422	$ 17,559
Current Loans		3,209,949	2,995,568
Total loans	[1]	3,234,371	3,013,127
Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		8,708	4,555
Current Loans		1,065,478	927,398
Total loans		1,074,186	931,953
Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
Current Loans		121,371	122,297
Total loans		121,371	122,297
Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		1,154	462
Current Loans		574,955	599,835
Total loans		576,109	600,297
Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		12,226	9,286
Current Loans		1,082,598	975,151
Total loans		1,094,824	984,437
Homeowner Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
Current Loans		27,924	29,118
Total loans		27,924	29,118
Home Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		681	1,774
Current Loans		263,519	253,791
Total loans		264,200	255,565
Home Equity Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		1,510	1,460
Current Loans		35,762	45,189
Total loans		37,272	46,649
Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		143	22
Current Loans		38,342	42,789
Total loans		38,485	42,811
30-59
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		8,154	5,137
30-59 | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		901	51
30-59 | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
30-59 | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		409	405
30-59 | Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		5,381	3,028
30-59 | Homeowner Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
30-59 | Home Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		655	883
30-59 | Home Equity Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		776	748
30-59 | Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		32	22
60-89
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		755	3,836
60-89 | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
60-89 | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
60-89 | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	9
60-89 | Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		652	2,964
60-89 | Homeowner Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
60-89 | Home Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		26	373
60-89 | Home Equity Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		76	490
60-89 | Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		1	0
Over 90
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		15,513	8,586
Over 90 | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		7,807	4,504
Over 90 | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
Over 90 | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		745	48
Over 90 | Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		6,193	3,294
Over 90 | Homeowner Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	0
Over 90 | Home Equity Lines [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		0	518
Over 90 | Home Equity Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		658	222
Over 90 | Other Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivable, recorded investment, past due		$ 110	$ 0
[1]	Includes net unamortized loan origination costs of $3.0 million and $2.6 million, respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand, respectively, at December 31, 2016 and 2015.

Loans (Impaired Loans) (Details

Loans (Impaired Loans) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	$ 26,772	$ 15,118
Collateral dependent impaired loans	[1]	7,079	17,138
Total Recorded Investment of Impaired Loans	[1]	33,851	32,256
Unpaid Principal of Impaired Loans with No Related Allowance		31,431	16,399
Unpaid Principal of Impaired Loans with Related Allowance		8,125	17,493
Total Unpaid Principal of Impaired Loans		39,556	33,892
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		606	2,583
Average Recorded Investment of Impaired Loans		31,323	24,610	$ 29,792
Interest Income Recognized on Impaired Loans		719	626	899
Commercial Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	4,676	4,292
Collateral dependent impaired loans	[1]	5,104	10,873
Unpaid Principal of Impaired Loans with No Related Allowance		9,019	5,101
Unpaid Principal of Impaired Loans with Related Allowance		6,087	10,855
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		448	1,633
Average Recorded Investment of Impaired Loans		13,201	14,847	22,971
Interest Income Recognized on Impaired Loans		239	327	658
Commercial Construction & Development [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	0
Collateral dependent impaired loans	[1]	0	0
Unpaid Principal of Impaired Loans with No Related Allowance		0	0
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
Average Recorded Investment of Impaired Loans		0	0	0
Interest Income Recognized on Impaired Loans		0	0	0
Commercial & Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	6,458	1,849
Collateral dependent impaired loans	[1]	662	2,024
Unpaid Principal of Impaired Loans with No Related Allowance		6,550	1,869
Unpaid Principal of Impaired Loans with Related Allowance		699	2,248
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		3	771
Average Recorded Investment of Impaired Loans		3,540	3,415	2,499
Interest Income Recognized on Impaired Loans		99	130	126
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	14,385	8,441
Collateral dependent impaired loans	[1]	1,285	2,895
Unpaid Principal of Impaired Loans with No Related Allowance		14,569	8,826
Unpaid Principal of Impaired Loans with Related Allowance		1,310	2,941
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		151	156
Average Recorded Investment of Impaired Loans		12,848	5,423	4,006
Interest Income Recognized on Impaired Loans		322	147	101
Homeowner Construction [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	0
Collateral dependent impaired loans	[1]	0	0
Unpaid Principal of Impaired Loans with No Related Allowance		0	0
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
Average Recorded Investment of Impaired Loans		0	0	0
Interest Income Recognized on Impaired Loans		0	0	0
Home Equity Lines [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	0	6
Collateral dependent impaired loans	[1]	0	522
Unpaid Principal of Impaired Loans with No Related Allowance		0	64
Unpaid Principal of Impaired Loans with Related Allowance		0	522
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	2
Average Recorded Investment of Impaired Loans		354	228	97
Interest Income Recognized on Impaired Loans		10	1	2
Home Equity Loans [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	1,137	530
Collateral dependent impaired loans	[1]	0	679
Unpaid Principal of Impaired Loans with No Related Allowance		1,177	539
Unpaid Principal of Impaired Loans with Related Allowance		0	783
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		0	21
Average Recorded Investment of Impaired Loans		1,233	487	100
Interest Income Recognized on Impaired Loans		38	11	4
Other Consumer [Member]
Financing Receivable, Impaired [Line Items]
Recorded Investment of Impaired Loans with No Related Allowance	[1]	116	0
Collateral dependent impaired loans	[1]	28	145
Unpaid Principal of Impaired Loans with No Related Allowance		116	0
Unpaid Principal of Impaired Loans with Related Allowance		29	144
No Related Allowance on Impaired Loans		0	0
Related Allowance on Impaired Loans		4	0
Average Recorded Investment of Impaired Loans		147	210	119
Interest Income Recognized on Impaired Loans		11	10	$ 8
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Total Recorded Investment of Impaired Loans	[1]	16,900	19,038
Total Unpaid Principal of Impaired Loans		22,355	20,073
Related Allowance on Impaired Loans		451	2,404
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Total Recorded Investment of Impaired Loans	[1]	15,670	11,336
Total Unpaid Principal of Impaired Loans		15,879	11,767
Related Allowance on Impaired Loans		151	156
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Total Recorded Investment of Impaired Loans	[1]	1,281	1,882
Total Unpaid Principal of Impaired Loans		1,322	2,052
Related Allowance on Impaired Loans		$ 4	$ 23
[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 impaired accruing loans (troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt), the recorded investment also includes accrued interest.

Loans (Troubled Debt Restructur

Loans (Troubled Debt Restructurings) (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2016USD ($)loan	Dec. 31, 2015USD ($)loan
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		13	9
Pre-Modification Recorded Investment	[1]	$ 11,391	$ 2,498
Post-Modification Recorded Investment	[1]	$ 11,391	$ 2,498
Commercial Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		1	1
Pre-Modification Recorded Investment	[1]	$ 776	$ 1,190
Post-Modification Recorded Investment	[1]	$ 776	$ 1,190
Commercial Construction & Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		0	0
Pre-Modification Recorded Investment	[1]	$ 0	$ 0
Post-Modification Recorded Investment	[1]	$ 0	$ 0
Commercial & Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		9	3
Pre-Modification Recorded Investment	[1]	$ 6,229	$ 584
Post-Modification Recorded Investment	[1]	$ 6,229	$ 584
Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		3	3
Pre-Modification Recorded Investment	[1]	$ 4,386	$ 619
Post-Modification Recorded Investment	[1]	$ 4,386	$ 619
Homeowner Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		0	0
Pre-Modification Recorded Investment	[1]	$ 0	$ 0
Post-Modification Recorded Investment	[1]	$ 0	$ 0
Home Equity Lines [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		0	0
Pre-Modification Recorded Investment	[1]	$ 0	$ 0
Post-Modification Recorded Investment	[1]	$ 0	$ 0
Home Equity Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		0	1
Pre-Modification Recorded Investment	[1]	$ 0	$ 70
Post-Modification Recorded Investment	[1]	$ 0	$ 70
Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring | loan		0	1
Pre-Modification Recorded Investment	[1]	$ 0	$ 35
Post-Modification Recorded Investment	[1]	$ 0	$ 35
[1]	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.

Loans (Troubled Debt Restruct72

Loans (Troubled Debt Restructurings Type of Modification) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	[1]	$ 11,391	$ 2,498
Below-market interest rate concession [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment		0	335
Payment deferral [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment		1,111	903
Maturity / amortization concession [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment		683	70
Interest only payments [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment		4,326	0
Combination [Member]
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Investment	[2]	$ 5,271	$ 1,190
[1]	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.
[2]	Loans included in this classification were modified with a combination of any two of the concessions listed in this table.

Loans (Troubled Debt Restruct73

Loans (Troubled Debt Restructurings Subsequent Default) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)loan	Dec. 31, 2015USD ($)loan
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	13	9
Payment Default [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans Modified as a Troubled Debt Restructuring	7	2
Recorded Investment on Modifications with Subsequent Default | $	$ 1,600	$ 290

Loans (Credit Quality Indicator

Loans (Credit Quality Indicators - Commercial) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	$ 1,746,145	$ 1,614,107
Pass [Member] | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	1,065,358	914,774
Pass [Member] | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	121,371	122,297
Pass [Member] | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	559,416	577,036
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	9,714	15,047
Special Mention [Member] | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	776	3,035
Special Mention [Member] | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	0	0
Special Mention [Member] | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	8,938	12,012
Classified [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	15,807	25,393
Classified [Member] | Commercial Mortgages [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	8,052	14,144
Classified [Member] | Commercial Construction & Development [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	0	0
Classified [Member] | Commercial & Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	$ 7,755	$ 11,249

Loans (Credit Quality Indicat75

Loans (Credit Quality Indicators - Residential, Consumer) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Under 90 Days Past Due [Member] | Accruing Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	$ 1,083,088	$ 973,771
Under 90 Days Past Due [Member] | Nonaccrual Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	5,543	7,372
Under 90 Days Past Due [Member] | Homeowner Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	27,924	29,118
Under 90 Days Past Due [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	1,116,555	1,010,261
Under 90 Days Past Due [Member] | Home Equity Lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	264,200	255,047
Under 90 Days Past Due [Member] | Home Equity Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	36,614	46,427
Under 90 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	38,375	42,811
Under 90 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	339,189	344,285
Over 90 Days Past Due [Member] | Accruing Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	0	0
Over 90 Days Past Due [Member] | Nonaccrual Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	6,193	3,294
Over 90 Days Past Due [Member] | Homeowner Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	0	0
Over 90 Days Past Due [Member] | Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	6,193	3,294
Over 90 Days Past Due [Member] | Home Equity Lines [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	0	518
Over 90 Days Past Due [Member] | Home Equity Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	658	222
Over 90 Days Past Due [Member] | Other Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	110	0
Over 90 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans Receivable	$ 768	$ 740

Loans (Analysis of Loan Servici

Loans (Analysis of Loan Servicing Rights) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Loan Servicing Rights [Roll Forward]
Beginning balance	$ 3,348	$ 2,989	$ 2,767
Loan servicing rights capitalized	1,412	1,406	869
Amortization	(1,267)	(1,047)	(647)
Decrease in impairment reserve	0	0	0
Ending balance	3,493	3,348	2,989
Valuation Allowance [Roll Forward]
Beginning balance	(1)	(2)	(69)
Loan servicing rights capitalized	0	0	0
Amortization	0	0	0
Decrease in impairment reserve	1	1	67
Ending balance	0	(1)	(2)
Total Loan Servicing Rights [Roll Forward]
Beginning Balance	3,347	2,987	2,698
Loan servicing rights capitalized	1,412	1,406	869
Amortization	(1,267)	(1,047)	(647)
Decrease in impairment reserve	1	1	67
Ending balance	$ 3,493	$ 3,347	$ 2,987

Loans (Estimated Aggregate Amor

Loans (Estimated Aggregate Amortization Expense) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Amortization Expense, Next Twelve Months	$ 1,137
Amortization Expense, Year Two	767
Amortization Expense, Year Three	517
Amortization Expense, Year Four	349
Amortization Expense, Year Five	235
Amortization Expense, Thereafter	488
Total estimated amortization expense	$ 3,493	$ 3,348	$ 2,989	$ 2,767

Loans (Loans Serviced for Other

Loans (Loans Serviced for Others, by Type of Loan) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	$ 624,083	$ 567,802
Residential Mortgage [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	522,766	458,629
Commercial Loan [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Balance of loans being serviced	$ 101,317	$ 109,173

Allowance for Loan Losses (Allo

Allowance for Loan Losses (Allowance for Loan Losses Rollforward Analysis) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		$ 27,069	$ 28,023	$ 27,886
Charge-offs		(7,012)	(2,305)	(1,949)
Recoveries		297	301	236
Provision		5,650	1,050	1,850
Ending Balance		26,004	27,069	28,023
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		9,140	8,202	8,022
Charge-offs		(5,816)	(809)	(977)
Recoveries		56	92	24
Provision		6,591	1,655	1,133
Ending Balance		9,971	9,140	8,202
Commercial Construction & Development [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		1,758	1,300	383
Charge-offs		0	0	0
Recoveries		0	0	0
Provision		(563)	458	917
Ending Balance		1,195	1,758	1,300
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance	[1]	8,202	7,987	7,835
Charge-offs	[1]	(759)	(671)	(558)
Recoveries	[1]	156	87	86
Provision	[1]	(607)	799	624
Ending Balance	[1]	6,992	8,202	7,987
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		19,100	17,489	16,240
Charge-offs		(6,575)	(1,480)	(1,535)
Recoveries		212	179	110
Provision		5,421	2,912	2,674
Ending Balance		18,158	19,100	17,489
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		5,460	5,430	6,450
Charge-offs		(200)	(207)	(132)
Recoveries		11	28	51
Provision		(19)	209	(939)
Ending Balance		5,252	5,460	5,430
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		2,509	2,713	2,511
Charge-offs		(237)	(618)	(282)
Recoveries		74	94	75
Provision		248	320	409
Ending Balance		2,594	2,509	2,713
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning Balance		$ 0	2,391	2,685
Charge-offs			0	0
Recoveries			0	0
Provision			(2,391)	(294)
Ending Balance			$ 0	$ 2,391
[1]	Commercial & industrial loans.

Allowance for Loan Losses (Al80

Allowance for Loan Losses (Allowance for Loan Losses by Segment & Impairment Methodology) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		$ 33,815	$ 32,226
Loans related allowance individually evaluated for impairment		606	2,583
Loans collectively evaluated for impairment		3,200,556	2,980,901
Loans related allowance collectively evaluated for impairment		25,398	24,486
Total loans	[1]	3,234,371	3,013,127
Allowance		26,004	27,069
Commercial Mortgages [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		9,776	15,141
Loans related allowance individually evaluated for impairment		448	1,633
Loans collectively evaluated for impairment		1,064,410	916,812
Loans related allowance collectively evaluated for impairment		9,523	7,507
Total loans		1,074,186	931,953
Commercial Construction & Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		0	0
Loans related allowance individually evaluated for impairment		0	0
Loans collectively evaluated for impairment		121,371	122,297
Loans related allowance collectively evaluated for impairment		1,195	1,758
Total loans		121,371	122,297
Commercial & Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		7,098	3,871
Loans related allowance individually evaluated for impairment		3	771
Loans collectively evaluated for impairment		569,011	596,426
Loans related allowance collectively evaluated for impairment		6,989	7,431
Total loans		576,109	600,297
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		15,661	11,333
Loans related allowance individually evaluated for impairment		151	156
Loans collectively evaluated for impairment		1,107,087	1,002,222
Loans related allowance collectively evaluated for impairment		5,101	5,304
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans individually evaluated for impairment		1,280	1,881
Loans related allowance individually evaluated for impairment		4	23
Loans collectively evaluated for impairment		338,677	343,144
Loans related allowance collectively evaluated for impairment		$ 2,590	$ 2,486
[1]	Includes net unamortized loan origination costs of $3.0 million and $2.6 million, respectively, and net unamortized premiums on purchased loans of $783 thousand and $84 thousand, respectively, at December 31, 2016 and 2015.

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 72,316	$ 69,798
Less accumulated depreciation	43,296	40,205
Total premises and equipment, net	29,020	29,593
Depreciation expense	3,700	3,400	$ 3,100
Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	6,020	6,020
Premises and Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	37,913	36,358
Furniture, Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 28,383	$ 27,420

Goodwill and Other Intangible82

Goodwill and Other Intangibles (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Aug. 01, 2015	Aug. 31, 2005
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 64,059	$ 64,059		$ 5,945
Amortization of intangibles	$ 1,284	$ 904	$ 644
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset useful life (in years)	18 months
Weston Financial acquisition [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill					$ 35,500
Weston Financial acquisition [Member] | Advisory Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset useful life (in years)	20 years
Halsey acquisition [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill				$ 5,900
Halsey acquisition [Member] | Advisory Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible asset useful life (in years)	15 years

Goodwill and Other Intangible83

Goodwill and Other Intangibles (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Aug. 01, 2015
Goodwill [Line Items]
Goodwill	$ 64,059	$ 64,059	$ 5,945
Commercial Banking [Member]
Goodwill [Line Items]
Goodwill	22,591	22,591
Wealth Management Services [Member]
Goodwill [Line Items]
Goodwill	$ 41,468	$ 41,468

Goodwill and Other Intangible84

Goodwill and Other Intangibles (Schedule of Components of Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Advisory Contracts [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 20,803	$ 20,803
Accumulated amortization	10,648	9,610
Net amount	10,155	11,193
Non-compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	369	369
Accumulated amortization	349	102
Net amount	$ 20	$ 267

Goodwill and Other Intangible85

Goodwill and Other Intangibles (Schedule of Amortization Annual Expense) (Details) $ in Thousands	Dec. 31, 2016USD ($)
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization Expense, Next Twelve Months	$ 1,034
Amortization Expense, Year Two	979
Amortization Expense, Year Three	943
Amortization Expense, Year Four	914
Amortization Expense, Year Five	891
Amortization Expense, Thereafter	5,414
Non-compete Agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization Expense, Next Twelve Months	20
Amortization Expense, Year Two	0
Amortization Expense, Year Three	0
Amortization Expense, Year Four	0
Amortization Expense, Year Five	0
Amortization Expense, Thereafter	0
Advisory Contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization Expense, Next Twelve Months	1,014
Amortization Expense, Year Two	979
Amortization Expense, Year Three	943
Amortization Expense, Year Four	914
Amortization Expense, Year Five	891
Amortization Expense, Thereafter	$ 5,414

Income Tax Expense (Narrative)

Income Tax Expense (Narrative) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 0	$ 0

Income Tax Expense (Schedule of

Income Tax Expense (Schedule of Components of Income Tax Expense) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current tax expense:
Federal									$ 19,444	$ 17,864	$ 16,286
State									2,061	1,194	866
Total current tax expense									21,505	19,058	17,152
Deferred tax expense (benefit):
Federal									796	2,003	1,820
State									72	(183)	27
Total deferred tax expense									868	1,820	1,847
Total income tax expense	$ 5,873	$ 5,863	$ 5,153	$ 5,484	$ 5,346	$ 4,964	$ 5,387	$ 5,181	$ 22,373	$ 20,878	$ 18,999

Income Tax Expense (Schedule 88

Income Tax Expense (Schedule of Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Tax expense at Federal statutory rate									$ 24,099	$ 22,520	$ 20,938
(Decrease) increase in taxes resulting from:
Tax-exempt income									(1,599)	(1,604)	(1,540)
Dividends received deduction									(58)	(57)	(29)
BOLI									(930)	(694)	(646)
Federal tax credits									(364)	(364)	(364)
Income Tax Reconciliation Change in fair value of contingent consideration									(314)	0	0
Acquisition related expenses									0	318	0
State income tax expense, net of federal income tax benefit									1,387	658	581
Other									152	101	59
Total income tax expense	$ 5,873	$ 5,863	$ 5,153	$ 5,484	$ 5,346	$ 4,964	$ 5,387	$ 5,181	$ 22,373	$ 20,878	$ 18,999

Income Tax Expense (Schedule 89

Income Tax Expense (Schedule of Gross Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets:
Allowance for loan losses	$ 9,621	$ 10,015
Defined benefit pension obligations	3,804	3,447
Deferred compensation	3,991	3,181
Deferred loan origination fees	1,999	2,001
Stock based compensation	1,519	1,772
Net unrealized losses on available for sale securities	4,008	0
Other	3,495	3,547
Deferred tax assets	28,437	23,963
Deferred tax liabilities:
Net unrealized gains on securities available for sale	0	(617)
Amortization of intangibles	(3,765)	(4,240)
Deferred loan origination costs	(5,156)	(5,089)
Loan servicing rights	(1,293)	(1,238)
Other	(1,419)	(1,009)
Deferred tax liabilities	(11,633)	(12,193)
Net deferred tax asset	$ 16,804	$ 11,770

Time Certificates of Deposit (N

Time Certificates of Deposit (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Time Certificates of Deposit [Abstract]
Time deposits greater than FDIC limit	$ 53.4	$ 45.1

Time Certificates of Deposit (S

Time Certificates of Deposit (Schedule of Time Certifcates of Deposit Maturities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Schedule Maturity Abstract]
Time Deposits Scheduled Maturity, Next Twelve Months	$ 409,292
Time Deposits Scheduled Maturity, Year Two	188,978
Time Deposits Scheduled Maturity, Year Three	216,245
Time Deposits Scheduled Maturity, Year Four	85,922
Time Deposits Scheduled Maturity, Year Five	60,752
Time Deposits Scheduled Maturity, Thereafter	424
Time deposits	$ 961,613	$ 833,898
Weighted Average Rate [Abstract]
Time Deposits Weighted Average Rate, Next Twelve Months	0.73%
Time Deposits Weighted Average Rate, Year Two	1.12%
Time Deposits Weighted Average Rate, Year Three	1.54%
Time Deposits Weighted Average Rate, Year Four	1.61%
Time Deposits Weighted Average Rate, Year Five	1.77%
Time Deposits Weighted Average Rate, Thereafter	1.89%
Total Time Deposits Weighted Average Rate	1.13%

Time Certificates of Deposit 92

Time Certificates of Deposit (Schedule of Time Certificates of Deposit $100 Thousand or More Maturities) (Details) $ in Thousands	Dec. 31, 2016USD ($)
Deposits [Abstract]
Time Deposits $100,000 or More Maturing in Three Months or Less	$ 82,626
Time Deposits $100,000 or More Maturing in Three Months Through Six Months	33,443
Time Deposits $100,000 or More Maturing in Six Months Through Twelve Months	35,301
Time Deposits $100,000 or More Maturing After 12 Months	126,372
Time Deposits $100,000 or More Balance at Year End	$ 277,742

Borrowings (Narrative - Federal

Borrowings (Narrative - Federal Home Loan Bank Advances) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank advances	$ 848,930	$ 378,973
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank advances	848,930	379,000
Unused line of credit with Federal Home Loan Bank	40,000	40,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 594,500	$ 644,800

Borrowings (Narrative - Junior

Borrowings (Narrative - Junior Subordinated Debentures) (Details) - USD ($) $ in Thousands	12 Months Ended	61 Months Ended	63 Months Ended	73 Months Ended	76 Months Ended
	Dec. 31, 2016	Sep. 15, 2010	Nov. 23, 2010	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Aug. 29, 2005
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures	$ 22,681			$ 22,681	$ 22,681	$ 22,681
Trust Preferred Securities [Member] | Trust I Capital Securities [Member] | Private Placement [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Amount of capital securities issued							$ 8,300
Minimum redemption period	5 years
Redemption rate		5.97%
Description of variable rate basis					three-month LIBOR
Basis spread on variable rate					1.45%
Trust Preferred Securities [Member] | Trust I Debentures [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures							8,300
Redemption rate		5.97%
Description of variable rate basis					three-month LIBOR
Basis spread on variable rate					1.45%
Trust Preferred Securities [Member] | Trust II Capital Securities [Member] | Private Placement [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Amount of capital securities issued							14,400
Minimum redemption period	5 years
Redemption rate			5.96%
Description of variable rate basis				three-month LIBOR
Basis spread on variable rate				1.45%
Trust Preferred Securities [Member] | Trust II Debentures [Member]
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Junior subordinated debentures							$ 14,400
Redemption rate			5.96%
Description of variable rate basis				three-month LIBOR
Basis spread on variable rate				1.45%

Borrowings (Federal Home Loan B

Borrowings (Federal Home Loan Bank Advances Maturity Schedule) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Federal Home Loan Bank advances	$ 848,930	$ 378,973
Federal Home Loan Bank of Boston [Member]
Federal Home Loan Bank, Advances, Fiscal Year Maturity [Abstract]
Scheduled Maturity, Next 12 months	420,075
Scheduled Maturity, Year Two	98,134
Scheduled Maturity, Year Three	137,258
Scheduled Maturity, Year Four	72,033
Scheduled Maturity, Year Five	51,222
Scheduled Maturity, Thereafter	70,208
Federal Home Loan Bank advances	$ 848,930	$ 379,000
Federal Home Loan Bank, Advances, Maturities Summary, Average Interest Rate of Amounts Due [Abstract]
Weighted Average Rate, Next 12 months	0.89%
Weighted Average Rate, Year Two	1.36%
Weighted Average Rate, Year Three	1.65%
Weighted Average Rate, Year Four	1.95%
Weighted Average Rate, Year Five	2.50%
Weighted Average Rate, Thereafter	3.81%
Weighted Average Rate, Total	1.49%

Borrowings (Certain Information

Borrowings (Certain Information of Federal Home Loan Bank of Boston Advances) (Details) - Federal Home Loan Bank of Boston [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Average amount outstanding during the period	$ 275,533	$ 155,874	$ 70,693
Amount outstanding at end of period	352,500	107,500	200,000
Highest month end balance during period	$ 367,500	$ 229,500	$ 200,000
Weighted-average interest rate at end of period	0.79%	0.55%	0.37%
Weighted-average interest rate during the period	0.73%	0.38%	0.35%

Shareholders' Equity (Narrative

Shareholders' Equity (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2006	Dec. 31, 2007	Dec. 31, 2016	Dec. 24, 2008
Dividends:
Amount of additional dividends the bank could have declared			$ 195.4
Reserved Shares:
Reserved shares available for grant			2,071,309
Amended and Restated Dividend Reinvestment and Stock Purchase Plan [Member]
Reserved Shares:
Reserved shares available for grant				607,500
2006 Stock Repurchase Plan [Member]
Stock Repurchase Program:
Authorized amount (in shares)	400,000
Authorized amount as a percentage of total common stock	3.00%
Cumulative amount of shares purchased			185,400
Shares repurchased, value		$ 4.8

Shareholders' Equity (Regulator

Shareholders' Equity (Regulatory Captial Requirements) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Parent Company [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital	$ 390,867	$ 367,443
Total Capital to Risk-Weighted Assets	12.26%	12.58%
Total Capital for Capital Adequacy Purposes	$ 255,093	$ 233,739
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets	8.00%	8.00%
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital	$ 364,655	$ 340,130
Tier 1 Capital to Risk Weighted-Assets	11.44%	11.64%
Tier 1 Capital Required For Capital Adequacy Purposes	$ 191,320	$ 175,304
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	$ 342,656	$ 318,131
Common Equity Tier 1 Capital to Risk Weighted Assets	10.75%	10.89%
Common Equity Tier 1 Required for Capital Adequacy	$ 143,490	$ 131,478
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	$ 364,655	$ 340,130
Tier 1 Leverage Capital to Average Assets	8.67%	9.37%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	$ 168,271	$ 145,191
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	4.00%	4.00%
Bank [Member]
Total Capital (to Risk-Weighted Assets):
Total Capital	$ 389,840	$ 366,676
Total Capital to Risk-Weighted Assets	12.23%	12.55%
Total Capital for Capital Adequacy Purposes	$ 255,050	$ 233,676
Total Capital for Capital Adequacy Purposes to Risk-Weighted Assets	8.00%	8.00%
Total Capital To Be Well Capitalized	$ 318,813	$ 292,095
Total Capital To Be Well Capitalized to Risk Weighted-Assets	10.00%	10.00%
Tier 1 Capital (to Risk-Weighted Assets):
Tier 1 Capital	$ 363,628	$ 339,363
Tier 1 Capital to Risk Weighted-Assets	11.41%	11.62%
Tier 1 Capital Required For Capital Adequacy Purposes	$ 191,288	$ 175,257
Tier 1 Capital Required for Capital Adequacy Purposes to Risk Weighted-Assets	6.00%	6.00%
Tier 1 Capital Required To Be Well Capitalized	$ 255,050	$ 233,676
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	$ 363,628	$ 339,363
Common Equity Tier 1 Capital to Risk Weighted Assets	11.41%	11.62%
Common Equity Tier 1 Required for Capital Adequacy	$ 143,466	$ 131,443
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	$ 207,228	$ 189,861
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	$ 363,628	$ 339,363
Tier 1 Leverage Capital to Average Assets	8.65%	9.36%
Tier 1 Leverage Capital Required for Capital Adequacy Purposes	$ 168,207	$ 145,103
Tier 1 Leverage Capital Required for Capital Adequacy Purposes to Average Assets	4.00%	4.00%
Tier 1 Leverage Capital Required To Be Well Capitalized	$ 210,259	$ 181,378
Tier 1 Leverage Capital Required To Be Well Capitalized to Average Assets	5.00%	5.00%

Derivative Financial Instrume99

Derivative Financial Instruments (Narrative) (Details) $ in Thousands	Dec. 31, 2016USD ($)derivative_instrument	Dec. 31, 2015USD ($)derivative_instrument
Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 60,000	$ 0
Interest rate swaps with customers [Member]
Derivatives, Fair Value [Line Items]
Notional amount	428,723	302,142
Mirror swaps with counterparties [Member]
Derivatives, Fair Value [Line Items]
Notional amount	428,723	302,142
Risk participation-in agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 28,460	21,474
Designated as Hedging Instrument [Member] | Interest rate caps [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments held | derivative_instrument	2
Notional amount	$ 22,700	22,700
Interest rate cap premium		$ 257
Interest rate cap strike		4.50%
Designated as Hedging Instrument [Member] | Interest rate swaps [Member]
Derivatives, Fair Value [Line Items]
Number of derivative instruments held | derivative_instrument	2	2
Notional amount	$ 60,000
Not Designated as Hedging Instrument [Member] | Interest rate swaps with customers [Member]
Derivatives, Fair Value [Line Items]
Notional amount	428,700	$ 302,100
Not Designated as Hedging Instrument [Member] | Risk participation-out agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	38,300	25,300
Not Designated as Hedging Instrument [Member] | Risk participation-in agreement [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 28,500	$ 21,500

Derivative Financial Instrum100

Derivative Financial Instruments (Fair Value of Derivatives by Balance Sheet Location) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative assets	$ 3,582	$ 9,490
Derivative liabilities	4,043	10,347
Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	3,582	9,490
Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	4,043	10,347
Interest rate swaps [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value	0	0
Interest rate swaps [Member] | Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value	378	0
Interest rate caps [Member] | Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge asset at fair value	134	187
Interest rate caps [Member] | Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Interest rate cash flow hedge liability at fair value	0	0
Interest rate lock commitments [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	1,133	1,220
Interest rate lock commitments [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	88	0
Commitments to sell mortgage loans [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	279	0
Commitments to sell mortgage loans [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	1,349	2,012
Interest rate swaps with customers [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	2,036	8,027
Interest rate swaps with customers [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	0	0
Mirror swaps with counterparties [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	0	0
Mirror swaps with counterparties [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	2,228	8,266
Risk participation-out agreement [Member] | Not Designated as Hedging Instrument [Member] | Other assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset not designated as hedging instruments	0	56
Risk participation-in agreement [Member] | Not Designated as Hedging Instrument [Member] | Other liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability not designated as hedging instruments	$ 0	$ 69

Derivative Financial Instrum101

Derivative Financial Instruments (Derivatives in Cash Flow Hedging Relationships, Effect in Statements of Income and Changes in Shareholders' Equity) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income (Effective Portion)	$ (257)	$ 244	$ 331
Gain (Loss) Recognized in Income (Ineffective Portion)	0	0	0
Interest Expense [Member] | Interest rate swaps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income (Ineffective Portion)	0	0	0
Interest Expense [Member] | Interest rate caps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income (Ineffective Portion)	0	0	0
Other Comprehensive Income (Loss) [Member] | Interest rate swaps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income (Effective Portion)	(224)	288	331
Other Comprehensive Income (Loss) [Member] | Interest rate caps [Member] | Cash Flow Hedge [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income (Effective Portion)	$ (33)	$ (44)	$ 0

Derivative Financial Instrum102

Derivative Financial Instruments (Derivatives not Designated as Hedging Instruments, Effect in Statements of Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 0	$ 0	$ 0
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	4,010	2,472	494
Interest rate lock commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(175)	28	800
Interest rate lock commitments [Member] | Mortgage banking revenues [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(175)	28	800
Commitments to sell mortgage loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	942	3	(1,442)
Commitments to sell mortgage loans [Member] | Mortgage banking revenues [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	942	3	(1,442)
Interest rate swaps with customers [Member] | Loan related derivative income [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(598)	7,569	4,989
Mirror swaps with counterparties [Member] | Loan related derivative income [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	3,854	(4,904)	(3,853)
Risk participation agreements [Member] | Loan related derivative income [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ (13)	$ (224)	$ 0

Balance Sheet Offsetting (Detai

Balance Sheet Offsetting (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Gross derivative assets at fair value	$ 7,812	$ 8,214
Derivative assets, offsetting positions	5,642	0
Derivative assets, net amount	2,170	8,214
Derivative assets, cash collateral pledged	0	0
Gross derivative liabilities at fair value	8,248	8,266
Derivative liabilities, offsetting positions	5,642	0
Derivative liabilities, net amount	2,606	8,266
Derivative liabilities, cash collateral pledged	1,428	8,343
Interest rate caps [Member]
Gross derivative assets at fair value	134	187
Derivative assets, offsetting positions	0	0
Derivative assets, net amount	134	187
Derivative assets, cash collateral pledged	0	0
Interest rate swaps with customers [Member]
Gross derivative assets at fair value	4,920	8,027
Derivative assets, offsetting positions	2,884	0
Derivative assets, net amount	2,036	8,027
Derivative assets, cash collateral pledged	0	0
Gross derivative liabilities at fair value	2,884	0
Derivative liabilities, offsetting positions	2,884	0
Derivative liabilities, net amount	0	0
Derivative liabilities, cash collateral pledged	0	0
Mirror swaps with counterparties [Member]
Gross derivative assets at fair value	2,758	0
Derivative assets, offsetting positions	2,758	0
Derivative assets, net amount	0	0
Derivative assets, cash collateral pledged	0	0
Gross derivative liabilities at fair value	4,986	8,266
Derivative liabilities, offsetting positions	2,758	0
Derivative liabilities, net amount	2,228	8,266
Derivative liabilities, cash collateral pledged	1,295	8,343
Interest rate swaps [Member]
Gross derivative liabilities at fair value	378
Derivative liabilities, offsetting positions	0
Derivative liabilities, net amount	378
Derivative liabilities, cash collateral pledged	133
Other assets [Member]
Derivative offset against collateral, net	2,170	8,214
Other assets [Member] | Interest rate caps [Member]
Derivative offset against collateral, net	134	187
Other assets [Member] | Interest rate swaps with customers [Member]
Derivative offset against collateral, net	2,036	8,027
Other assets [Member] | Mirror swaps with counterparties [Member]
Derivative offset against collateral, net	0	0
Other liabilities [Member]
Derivative offset against collateral, net	1,178	(77)
Other liabilities [Member] | Interest rate swaps with customers [Member]
Derivative offset against collateral, net	0	0
Other liabilities [Member] | Mirror swaps with counterparties [Member]
Derivative offset against collateral, net	933	$ (77)
Other liabilities [Member] | Interest rate swaps [Member]
Derivative offset against collateral, net	$ 245

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Thousands	Aug. 01, 2015	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, amortized cost		$ 29,400	$ 33,200
Mortgage loans held for sale, fair value		29,434	33,969
Mortgage loans held for sale difference between fair value and principal amount		40	731
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		29,434	33,969
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		0	0
Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Allowance for loan loss on collateral dependent impaired loans		$ 469	$ 2,400
Contingent Consideration [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Earn-out period post acquisition	5 years
Contingent Consideration [Member] | Minimum [Member] | Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate for contingent consideration liability		3.00%
Contingent Consideration [Member] | Maximum [Member] | Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Discount rate for contingent consideration liability		4.00%

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value Mortgage Loans Held For Sale, Interest Rate Lock Commitments And Commitments to Sell Changes in Fair Value Disclosures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on mortgage loans held for sale	$ (691)	$ (48)	$ 598
Amount of Gain (Loss) Recognized in Income on Derivative	0	0	0
Total change in fair value	76	(17)	(44)
Interest rate lock commitments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	(175)	28	800
Commitments to sell mortgage loans [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income on Derivative	$ 942	$ 3	$ (1,442)

Fair Value Measurements (Assets

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - USD ($) $ in Thousands		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		$ 739,912		$ 375,044
Mortgage loans held for sale, fair value		29,434		33,969
Derivative assets		3,582		9,490
Derivative liabilities		4,043		10,347
Contingent consideration liability		2,047	[1]	2,945	[1]	$ 0
Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		108,440		77,015
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		588,085		234,856
Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		14,485		36,080
Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		26,736		25,138
Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		2,166		1,955
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0		0
Derivative liabilities		0		0
Contingent consideration liability	[1]	0		0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		3,582		9,490
Derivative liabilities		4,043		10,347
Contingent consideration liability	[1]	0		0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets		0		0
Derivative liabilities		0		0
Contingent consideration liability	[1]	2,047		2,945
Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		29,434		33,969
Total assets at fair value on a recurring basis		772,928		418,503
Total liabilities at fair value on a recurring basis		6,090		13,292
Recurring [Member] | Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		108,440		77,015
Recurring [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		588,085		234,856
Recurring [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		14,485		36,080
Recurring [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		26,736		25,138
Recurring [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		2,166		1,955
Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		0		0
Total assets at fair value on a recurring basis		0		0
Total liabilities at fair value on a recurring basis		0		0
Recurring [Member] | Level 1 [Member] | Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 1 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 1 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 1 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 1 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		29,434		33,969
Total assets at fair value on a recurring basis		772,928		418,503
Total liabilities at fair value on a recurring basis		4,043		10,347
Recurring [Member] | Level 2 [Member] | Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		108,440		77,015
Recurring [Member] | Level 2 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		588,085		234,856
Recurring [Member] | Level 2 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		14,485		36,080
Recurring [Member] | Level 2 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		26,736		25,138
Recurring [Member] | Level 2 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		2,166		1,955
Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage loans held for sale, fair value		0		0
Total assets at fair value on a recurring basis		0		0
Total liabilities at fair value on a recurring basis		2,047		2,945
Recurring [Member] | Level 3 [Member] | Obligations of U.S. government agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 3 [Member] | Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 3 [Member] | Obligations of states and political subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 3 [Member] | Individual name issuer trust preferred debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		0		0
Recurring [Member] | Level 3 [Member] | Corporate bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities		$ 0		$ 0
[1]	The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets.

Fair Value Measurements Fair Va

Fair Value Measurements Fair Value Measurements (Change in contingent consideration) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 2,945	[1]	$ 0
Initial recognition	0		2,904
Change in fair value	(898)		41		$ 0
Payments	0		0
Ending Balance	$ 2,047	[1]	$ 2,945	[1]	$ 0
[1]	The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets.

Fair Value Measurements (Ass108

Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans	[1]	$ 7,079	$ 17,138
Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent impaired loans		3,828	10,545
Property acquired through foreclosure or repossession		605	270
Total assets at fair value on a nonrecurring basis		4,433	10,815
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		3,828	10,545
Property acquired through foreclosure or repossession		605	270
Total assets at fair value on a nonrecurring basis		$ 4,433	$ 10,815
[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 impaired accruing loans (troubled debt restructurings for which management has concluded that the collectability of the loan is not in doubt), the recorded investment also includes accrued interest.

Fair Value Measurements (Qualit

Fair Value Measurements (Qualitative Information About Level 3 Assets Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans	[1]	$ 7,079	$ 17,138
Nonrecurring [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans		3,828	10,545
Property acquired through foreclosure or repossession		605	270
Nonrecurring [Member] | Level 3 [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Collateral dependent impaired loans		3,828	10,545
Property acquired through foreclosure or repossession		$ 605	$ 270
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Collateral Dependent Impaired Loans [Member] | Minimum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		10.00%	0.00%
Appraisal adjustments	[2]	0.00%
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Collateral Dependent Impaired Loans [Member] | Maximum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		20.00%	20.00%
Appraisal adjustments	[2]	10.00%
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Collateral Dependent Impaired Loans [Member] | Weighted Average [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		15.00%	2.00%
Appraisal adjustments	[2]	9.00%
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Minimum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		10.00%	12.00%
Appraisal adjustments	[2]	6.00%	32.00%
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Maximum [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		12.00%	12.00%
Appraisal adjustments	[2]	50.00%	32.00%
Nonrecurring [Member] | Level 3 [Member] | Appraisals Of Collateral [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Weighted Average [Member]
Fair Value Inputs Assets Qualitative Information [Line Items]
Discount for costs to sell		11.00%	12.00%
Appraisal adjustments	[2]	24.00%	32.00%
[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 impaired accruing loans (troubled debt restructurings for which management has concluded that the collectability 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	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	$ 15,633	$ 20,023
Loans, net of allowance of loan losses	3,208,367	2,986,058
Time deposits	961,613	833,898
Federal Home Loan Bank advances	848,930	378,973
Junior subordinated debentures	22,681	22,681
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	15,633	20,023
Loans, net of allowance of loan losses	3,208,367	2,986,058
Time deposits	961,613	833,898
Federal Home Loan Bank advances	848,930	378,973
Junior subordinated debentures	22,681	22,681
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	15,920	20,516
Loans, net of allowance of loan losses	3,218,651	3,004,782
Time deposits	962,374	834,574
Federal Home Loan Bank advances	852,888	388,275
Junior subordinated debentures	16,970	16,468
Estimate of Fair Value Measurement [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	0	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
Estimate of Fair Value Measurement [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	15,920	20,516
Loans, net of allowance of loan losses	0	0
Time deposits	962,374	834,574
Federal Home Loan Bank advances	852,888	388,275
Junior subordinated debentures	16,970	16,468
Estimate of Fair Value Measurement [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Held to maturity securities	0	0
Loans, net of allowance of loan losses	3,218,651	3,004,782
Time deposits	0	0
Federal Home Loan Bank advances	0	0
Junior subordinated debentures	$ 0	$ 0

Employee Benefits (Narrative) (

Employee Benefits (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended			120 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 30, 2023
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, employer matching contribution, percent of employee gross pay	4.00%
Defined contribution plan, employer matching contributions	$ 2,300	$ 1,800	$ 1,800
Other incentive-based compensation expense	16,000	14,300	$ 13,800
Deferred compensation plan, accrued liability	10,800	8,600
Qualified Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded (unfunded) status at end of period	2,836	(1,840)
Accumulated benefit obligation	65,800	60,300
Estimated amortization of prior service cost (credit) from accumulated other comprehensive loss into net period benefit cost, next year	(23)
Estimated amortization of (gain) loss from accumulated other comprehensive loss into net period benefit cost, next year	$ 1,100
Fair value of equity securities, maximum percentage held by a single issuer	10.00%
Estimated future employer contributions in next fiscal year	$ 3,000
Qualified Pension Plan [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, minimum	50.00%
Target plan asset allocation, investment ranges, maximum	70.00%
Qualified Pension Plan [Member] | Small-Cap Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, maximum	20.00%
Qualified Pension Plan [Member] | Mid-Cap Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, maximum	20.00%
Qualified Pension Plan [Member] | International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, maximum	30.00%
Qualified Pension Plan [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, minimum	30.00%
Target plan asset allocation, investment ranges, maximum	50.00%
Qualified Pension Plan [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, minimum	0.00%
Target plan asset allocation, investment ranges, maximum	10.00%
Qualified Pension Plan [Member] | High Yield Bond [Member]
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocation, investment ranges, maximum	10.00%
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Available-for-sale securities and other short-term investments, rabbi trusts	$ 11,700	12,300
Funded (unfunded) status at end of period	(13,154)	(13,015)
Accumulated benefit obligation	12,000	$ 11,700
Estimated amortization of prior service cost (credit) from accumulated other comprehensive loss into net period benefit cost, next year	(1)
Estimated amortization of (gain) loss from accumulated other comprehensive loss into net period benefit cost, next year	261
Estimated future employer contributions in next fiscal year	$ 779
Scenario, Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Transition Period Pension Plan Amendment				10 years

Employee Benefits (Schedule of

Employee Benefits (Schedule of Net Funded (Unfunded) Status) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Qualified Pension Plan [Member]
Change in Benefit Obligation:
Benefit obligation at beginning of period	$ 67,550	$ 73,149
Service cost	2,148	2,459	$ 2,152
Interest cost	2,576	2,928	2,891
Actuarial (gain) loss	3,888	(5,410)
Benefits paid	(3,072)	(5,430)
Administrative expenses	(139)	(146)
Benefit obligation at end of period	72,951	67,550	73,149
Change in Plan Assets:
Fair value of plan assets at beginning of period	65,710	67,613
Actual return on plan assets	4,788	673
Employer contributions	8,500	3,000
Benefits paid	(3,072)	(5,430)
Administrative expenses	(139)	(146)
Fair value of plan assets at end of period	75,787	65,710	67,613
Funded (unfunded) status at end of period	2,836	(1,840)
Non-Qualified Retirement Plans [Member]
Change in Benefit Obligation:
Benefit obligation at beginning of period	13,015	13,097
Service cost	122	78	46
Interest cost	432	490	478
Actuarial (gain) loss	374	88
Benefits paid	(789)	(738)
Administrative expenses	0	0
Benefit obligation at end of period	13,154	13,015	13,097
Change in Plan Assets:
Fair value of plan assets at beginning of period	0	0
Actual return on plan assets	0	0
Employer contributions	789	738
Benefits paid	(789)	(738)
Administrative expenses	0	0
Fair value of plan assets at end of period	0	0	$ 0
Funded (unfunded) status at end of period	$ (13,154)	$ (13,015)

Employee Benefits (Components o

Employee Benefits (Components of Accumulated Other Comprehensive Income(Loss)) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Qualified Pension Plan [Member]
Components of Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net actuarial loss	$ 15,593	$ 12,688
Prior service credit	(62)	(84)
Total pre-tax amounts recognized in accumulated other comprehensive income	15,531	12,604
Non-Qualified Retirement Plans [Member]
Components of Accumulated Other Comprehensive Income (Loss), before Tax [Abstract]
Net actuarial loss	4,519	4,392
Prior service credit	(1)	(2)
Total pre-tax amounts recognized in accumulated other comprehensive income	$ 4,518	$ 4,390

Employee Benefits (Component114

Employee Benefits (Components of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net (gain) loss		$ 4,106	$ (1,478)	$ 14,000
Prior service cost	[1]	(15)	(17)	(16)
Recognized in other comprehensive (loss) income		(3,055)	2,948	(13,493)
Qualified Pension Plan [Member]
Net Periodic Benefit Cost:
Service cost		2,148	2,459	2,152
Interest cost		2,576	2,928	2,891
Expected return on plan assets		(4,633)	(4,515)	(4,063)
Amortization of prior service credit		(23)	(23)	(23)
Recognized net actuarial loss		828	1,249	461
Net periodic benefit cost		896	2,098	1,418
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net (gain) loss		2,904	(2,816)	10,993
Prior service cost		23	23	23
Recognized in other comprehensive (loss) income		2,927	(2,793)	11,016
Total recognized in net periodic benefit cost and other comprehensive income (loss)		3,823	(695)	12,434
Non-Qualified Retirement Plans [Member]
Net Periodic Benefit Cost:
Service cost		122	78	46
Interest cost		432	490	478
Expected return on plan assets		0	0	0
Amortization of prior service credit		(1)	(1)	(1)
Recognized net actuarial loss		247	245	70
Net periodic benefit cost		800	812	593
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (on a pre-tax basis):
Net (gain) loss		127	(156)	2,476
Prior service cost		1	1	1
Recognized in other comprehensive (loss) income		128	(155)	2,477
Total recognized in net periodic benefit cost and other comprehensive income (loss)		$ 928	$ 657	$ 3,070
[1]	The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income.

Employee Benefits (Weighted-Ave

Employee Benefits (Weighted-Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Qualified Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	4.18%	4.48%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate		4.125%	4.875%
Equivalent single discount rate for benefit obligations	4.48%
Equivalent single discount rate for service cost	4.63%
Equivalent single discount rate for interest cost	3.88%
Expected long-term return on plan assets	6.75%	7.25%	7.25%
Rate of compensation increase	3.75%	3.75%	3.75%
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	4.00%	4.20%
Rate of compensation increase	3.75%	3.75%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate		3.90%	4.60%
Equivalent single discount rate for benefit obligations	4.20%
Equivalent single discount rate for service cost	4.59%
Equivalent single discount rate for interest cost	3.44%
Rate of compensation increase	3.75%	3.75%	3.75%

Employee Benefits (Schedule 116

Employee Benefits (Schedule of Fair Value of Qualified Pension Plan Assets) (Details) - Qualified Pension Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	100.00%	100.00%
Fair value of plan assets	$ 75,787	$ 65,710	$ 67,613
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	54,361	46,011
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21,426	19,699
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	63.80%	63.40%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	32.40%	34.60%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actual Plan Asset Allocations	3.80%	2.00%
Fair value of plan assets	$ 2,880	$ 1,598
Cash and Cash Equivalents [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,880	1,598
Cash and Cash Equivalents [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and Cash Equivalents [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of U.S Government Agencies and U.S. Government-Sponsored Enterprises [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,233	3,306
Obligations of U.S Government Agencies and U.S. Government-Sponsored Enterprises [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of U.S Government Agencies and U.S. Government-Sponsored Enterprises [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,233	3,306
Obligations of U.S Government Agencies and U.S. Government-Sponsored Enterprises [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of states and political subdivisions [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,418	3,438
Obligations of states and political subdivisions [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Obligations of states and political subdivisions [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,418	3,438
Obligations of states and political subdivisions [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate bonds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,775	12,955
Corporate bonds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate bonds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,775	12,955
Corporate bonds [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	33,893	29,433
Common Stocks [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	33,893	29,433
Common Stocks [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stocks [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17,588	14,980
Mutual Funds [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17,588	14,980
Mutual Funds [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Funds [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

Employee Benefits (Estimated Fu

Employee Benefits (Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2016USD ($)
Qualified Pension Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Future Payments, Next Twelve Months	$ 3,709
Expected Future Payments, Year Two	3,064
Expected Future Payments, Year Three	3,169
Expected Future Payments, Year Four	3,991
Expected Future Payments, Year Five	3,682
Expected Future Payments, Thereafter	24,864
Non-Qualified Retirement Plans [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Expected Future Payments, Next Twelve Months	779
Expected Future Payments, Year Two	772
Expected Future Payments, Year Three	801
Expected Future Payments, Year Four	895
Expected Future Payments, Year Five	881
Expected Future Payments, Thereafter	$ 4,248

Share-Based Compensation Arr118

Share-Based Compensation Arrangements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Apr. 23, 2013	Apr. 28, 2009	Apr. 22, 2003
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$ 1.7
Weighted average recognition period (in years)	1 year 9 months 2 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share options exercised total intrinsic value	$ 3.2	$ 1.2	$ 1
Cliff vesting period (years)	3 years		3 years
Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested share units	22,175	16,275	11,630
Cliff vesting period (years)	3 years		3 years
Performance Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards minimum shares earned to target percentage	0.00%
Performance share awards maximum shares earned to target percentage	200.00%
Nonvested share units	47,532
Cliff vesting period (years)	3 years	3 years	3 years
Performance share awards, shares vesting	101,998
Minimum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		3 years
Minimum [Member] | Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		3 years
Maximum [Member] | Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		5 years
Maximum [Member] | Time Based Nonvested Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		5 years
2013 Stock Option and Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized				1,748,250
Two Thousand Three Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized						600,000
Two Thousand Three Stock Incentive Plan [Member] | Stock Options and Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized						200,000
Amended and Restated Two Thousand Three Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized					1,200,000
Amended and Restated Two Thousand Three Stock Incentive Plan [Member] | Stock Options and Stock Appreciation Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized					400,000

Share-Based Compensation Arr119

Share-Based Compensation Arrangements (Compensation Cost for Share-based Compensation Arrangements) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-based compensation expense	$ 2,190	$ 2,074	$ 1,880
Related income tax benefit	$ 810	$ 767	$ 676

Share-Based Compensation Arr120

Share-Based Compensation Arrangements (Share Options Fair Value Assumptions) (Details) - Stock Options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted	53,400	48,600	25,850
Cliff vesting period (years)	3 years		3 years
Expected term (years)	7 years 6 months	7 years 6 months	8 years
Expected dividend yield	3.89%	3.94%	3.83%
Weighted average expected volatility	29.99%	40.76%	41.84%
Weighted average risk-free interest rate	1.66%	1.95%	2.27%
Weighted average grant-date fair value	$ 7.92	$ 11.15	$ 9.92
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		3 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cliff vesting period (years)		5 years

Share-Based Compensation Arr121

Share-Based Compensation Arrangements (Share Options Activity) (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Share Options:
Beginning of period	309,116
Granted	53,400	48,600	25,850
Exercised	(143,237)
Forfeited or expired	0
End of period	219,279	309,116
Options exercisable	89,954
Options expected to vest in future periods	129,325
Weighted Average Exercise Price (in dollars per share):
Beginning of period	$ 26.84
Granted	40.25
Exercised	22.87
Forfeited or expired	0
End of period	32.70	$ 26.84
Options exercisable	25.34
Options expected to vest in future periods	$ 37.82
Outstanding Weighted Average Remaining Contractual Term	7 years 2 months
Exercisable Weighted Average Remaining Contractual Term	4 years 9 months 7 days
Expected to Vest Weighted Average Remaining Contractual Term	8 years 10 months 5 days
Outstanding Aggregate Intrinsic Value	$ 5,121
Exercisable Aggregate Intrinsic Value	2,763
Expected to Vest Aggregate Intrinsic Value	$ 2,358

Share-Based Compensation Arr122

Share-Based Compensation Arrangements (Stock Options Outstanding and Options Exercisable) (Details)	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options Outstanding, Number of Share Options | shares	219,279
Options Outstanding, Weighted Average Remaining Life (Years)	7 years 2 months
Options Outstanding, Weighted Average Exercise Price	$ 32.70
Options Exercisable, Number of Share Options | shares	89,954
Options Exercisable, Weighted Average Exercise Price	$ 25.34
$15.01 to $20.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	15.01
Exercise Price Ranges, Upper Range Limit	$ 20
Options Outstanding, Number of Share Options | shares	13,200
Options Outstanding, Weighted Average Remaining Life (Years)	2 years 11 months 4 days
Options Outstanding, Weighted Average Exercise Price	$ 17.52
Options Exercisable, Number of Share Options | shares	13,200
Options Exercisable, Weighted Average Exercise Price	$ 17.52
$20.01 to $25.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	20.01
Exercise Price Ranges, Upper Range Limit	$ 25
Options Outstanding, Number of Share Options | shares	54,090
Options Outstanding, Weighted Average Remaining Life (Years)	4 years 6 months 6 days
Options Outstanding, Weighted Average Exercise Price	$ 23.08
Options Exercisable, Number of Share Options | shares	47,090
Options Exercisable, Weighted Average Exercise Price	$ 22.84
$25.01 to $30.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	25.01
Exercise Price Ranges, Upper Range Limit	$ 30
Options Outstanding, Number of Share Options | shares	0
Options Outstanding, Weighted Average Remaining Life (Years)	0 years
Options Outstanding, Weighted Average Exercise Price	$ 0
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0
$30.01 to $35.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	30.01
Exercise Price Ranges, Upper Range Limit	$ 35
Options Outstanding, Number of Share Options | shares	51,689
Options Outstanding, Weighted Average Remaining Life (Years)	6 years 10 months 26 days
Options Outstanding, Weighted Average Exercise Price	$ 32.76
Options Exercisable, Number of Share Options | shares	29,564
Options Exercisable, Weighted Average Exercise Price	$ 32.77
$35.01 to $40.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	35.01
Exercise Price Ranges, Upper Range Limit	$ 40
Options Outstanding, Number of Share Options | shares	46,900
Options Outstanding, Weighted Average Remaining Life (Years)	8 years 8 months 28 days
Options Outstanding, Weighted Average Exercise Price	$ 39.39
Options Exercisable, Number of Share Options | shares	100
Options Exercisable, Weighted Average Exercise Price	$ 39.55
$40.01 to $45.00 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price Ranges, Lower Range Limit	40.01
Exercise Price Ranges, Upper Range Limit	$ 45
Options Outstanding, Number of Share Options | shares	53,400
Options Outstanding, Weighted Average Remaining Life (Years)	9 years 9 months 18 days
Options Outstanding, Weighted Average Exercise Price	$ 40.25
Options Exercisable, Number of Share Options | shares	0
Options Exercisable, Weighted Average Exercise Price	$ 0

Share-Based Compensation Arr123

Share-Based Compensation Arrangements (Nonvested Share Units Activity) (Details) - Time Based Nonvested Shares [Member] - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Shares:
Beginning of period	47,225
Granted	22,175	16,275	11,630
Vested	(16,797)
Forfeited	(2,928)
End of period	49,675	47,225
Weighted Average Grant Date Fair Value (in dollars per share):
Beginning of period	$ 33.46
Granted	38.82
Vested	29.24
Forfeited	36.11
End of period	$ 37.12	$ 33.46

Share-Based Compensation Arr124

Share-Based Compensation Arrangements (Nonvested Performance Shares Outstanding) (Details) - Performance Based Nonvested Shares [Member]	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards, shares vesting	101,998
2016 Grant [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 36.11
Performance share awards, shares vesting percentages	140.00%
Performance share awards, shares vesting	47,532
2015 Grant [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 38.02
Performance share awards, shares vesting percentages	142.00%
Performance share awards, shares vesting	37,683
2014 Grant [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance share awards granted, grant date fair value | $ / shares	$ 34.66
Performance share awards, shares vesting percentages	133.00%
Performance share awards, shares vesting	16,783

Share-Based Compensation Arr125

Share-Based Compensation Arrangements (Nonvested Performance Shares Activity) (Details) - Performance Based Nonvested Shares [Member]	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Number of Shares:
Beginning of period | shares	110,891
Granted | shares	47,532
Vested | shares	(48,090)
Forfeited | shares	(8,335)
End of period | shares	101,998
Weighted Average Grant Date Fair Value (in dollars per share):
Beginning of period | $ / shares	$ 32.81
Granted | $ / shares	36.11
Vested | $ / shares	27.30
Forfeited | $ / shares	37.26
End of period | $ / shares	$ 36.58

Business Segments (Statement of

Business Segments (Statement of Operations and Total Assets by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Net interest income (expense)	$ 28,588	$ 27,379	$ 26,776	$ 27,735	$ 26,255	$ 25,997	$ 26,028	$ 25,702	$ 110,478	$ 103,982	$ 99,505
Provision for loan losses	2,900	1,800	450	500	750	200	100	0	5,650	1,050	1,850
Net interest income after provision for loan losses	25,688	25,579	26,326	27,235	25,505	25,797	25,928	25,702	104,828	102,932	97,655
Noninterest income	17,320	17,261	15,914	14,634	15,146	13,913	15,261	14,020	65,129	58,340	59,015
Depreciation and amortization expense									4,935	4,285	3,777
Other noninterest expenses									96,168	92,644	93,070
Total noninterest expense	24,973	24,650	26,030	25,450	24,561	24,538	24,299	23,531	101,103	96,929	96,847
Income before income taxes	18,035	18,190	16,210	16,419	16,090	15,172	16,890	16,191	68,854	64,343	59,823
Income tax expense (benefit)	5,873	5,863	5,153	5,484	5,346	4,964	5,387	5,181	22,373	20,878	18,999
Net income	12,162	$ 12,327	$ 11,057	$ 10,935	10,744	$ 10,208	$ 11,503	$ 11,010	46,481	43,465	40,824
Total assets at period end	4,381,115				3,771,604				4,381,115	3,771,604	3,586,874
Expenditures for long-lived assets									3,112	5,479	5,226
Commercial Banking [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									91,221	84,757	80,500
Provision for loan losses									5,650	1,050	1,850
Net interest income after provision for loan losses									85,571	83,707	78,650
Noninterest income									24,783	20,618	17,575
Depreciation and amortization expense									2,771	2,584	2,447
Other noninterest expenses									58,452	55,203	52,639
Total noninterest expense									61,223	57,787	55,086
Income before income taxes									49,131	46,538	41,139
Income tax expense (benefit)									16,790	15,330	13,497
Net income									32,341	31,208	27,642
Total assets at period end	3,354,633				3,152,231				3,354,633	3,152,231	2,986,453
Expenditures for long-lived assets									2,267	4,714	3,474
Wealth Management Services [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									(66)	(47)	(24)
Provision for loan losses									0	0	0
Net interest income after provision for loan losses									(66)	(47)	(24)
Noninterest income									37,569	35,416	33,378
Depreciation and amortization expense									1,940	1,488	1,127
Other noninterest expenses									25,239	25,632	22,386
Total noninterest expense									27,179	27,120	23,513
Income before income taxes									10,324	8,249	9,841
Income tax expense (benefit)									3,692	3,475	3,724
Net income									6,632	4,774	6,117
Total assets at period end	64,625				63,801				64,625	63,801	52,720
Expenditures for long-lived assets									464	411	1,578
Corporate [Member]
Segment Reporting Information [Line Items]
Net interest income (expense)									19,323	19,272	19,029
Provision for loan losses									0	0	0
Net interest income after provision for loan losses									19,323	19,272	19,029
Noninterest income									2,777	2,306	8,062
Depreciation and amortization expense									224	213	203
Other noninterest expenses									12,477	11,809	18,045
Total noninterest expense									12,701	12,022	18,248
Income before income taxes									9,399	9,556	8,843
Income tax expense (benefit)									1,891	2,073	1,778
Net income									7,508	7,483	7,065
Total assets at period end	$ 961,857				$ 555,572				961,857	555,572	547,701
Expenditures for long-lived assets									$ 381	$ 354	$ 174

Other Comprehensive Income (127

Other Comprehensive Income (Loss) (Activity in Other Comprehensive Income) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Change in fair value of securities available for sale, before tax		$ (12,502)	$ (4,926)		$ 1,601
Change in fair value of securities available for sale, tax		(4,626)	(1,755)		580
Change is fair value of securities available for sale		(7,876)	(3,171)		1,021
Net (gains) losses on securities classified into earnings, before tax		0	0		0
Net (gains) losses on securities classified into earnings, tax		0	0		0
Net (gains) losses on securities classified into earnings		0	0		0
Net change in fair value of securities available for sale, before tax		(12,502)	(4,926)		1,601
Net change in fair value of securities available for sale, tax		(4,626)	(1,755)		580
Net change in fair value of securities available for sale		(7,876)	(3,171)		1,021
Net change in fair value of cash flow hedges, before tax		(403)	(102)		(56)
Net change in fair value of cash flow hedges, tax		(146)	(49)		(18)
Change in fair value of cash flow hedges		(257)	(53)		(38)
Net cash flow hedge losses reclassified into earnings, before tax		0	469	[1]	577	[1]
Net cash flow hedge losses reclassified into earnings, tax		0	172	[1]	208	[1]
Net cash flow hedge losses reclassified into earnings		0	297	[1]	369	[1]
Change in fair value of cash flow hedges, before tax		(403)	367		521
Change in fair value of cash flow hedges, tax		(146)	123		190
Net change in fair value of cash flow hedges		(257)	244		331
Defined benefit plan obligation adjustment, before tax		(4,106)	1,478		(14,000)
Defined benefit plan obligation adjustment, tax		(1,518)	376		(5,067)
Defined benefit plan obligation adjustment		(2,588)	1,102		(8,933)
Amortization of net actuarial losses, before tax	[2]	1,075	1,494		531
Amortization of net actuarial losses, tax	[2]	397	542		190
Amortization of net actuarial losses	[2]	678	952		341
Amortization of net prior service credits, before tax	[2]	(24)	(24)		(24)
Amortization of net prior service credits, tax	[2]	(9)	(7)		(8)
Amortization of net prior service credits	[2]	(15)	(17)		(16)
Net change in defined benefit plan obligations, before tax		(3,055)	2,948		(13,493)
Net change in defined benefit plan obligations, tax		(1,130)	911		(4,885)
Net change in defined benefit plan obligations		(1,925)	2,037		(8,608)
Total other comprehensive income (loss), before tax		(15,960)	(1,611)		(11,371)
Total other comprehensive income (loss), tax		(5,902)	(721)		(4,115)
Total other comprehensive (loss) income, net of tax		(10,058)	(890)		(7,256)
Net Unrealized Gains on AFS Securities [Member]
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract]
Total other comprehensive (loss) income, net of tax		$ (7,876)	$ (3,171)		$ 1,021
[1]	The pre-tax amount is included in interest expense on junior subordinated debentures in the Consolidated Statements of Income.
[2]	The pre-tax amount is included in salaries and employee benefits expense in the Consolidated Statements of Income.

Other Comprehensive Income (128

Other Comprehensive Income (Loss) (Components of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated other comprehensive income (loss), beginning balance	$ (9,699)
Net other comprehensive income (loss)	(10,058)	$ (890)	$ (7,256)
Accumulated other comprehensive income (loss), ending balance	(19,757)	(9,699)
Net Unrealized Gains on AFS Securities [Member]
Accumulated other comprehensive income (loss), beginning balance	1,051	4,222	3,201
Other comprehensive income (loss) before reclassifications, net of tax	(7,876)	(3,171)	1,021
Amounts reclassified from accumulated other comprehensive income, net of tax	0	0	0
Net other comprehensive income (loss)	(7,876)	(3,171)	1,021
Accumulated other comprehensive income (loss), ending balance	(6,825)	1,051	4,222
Net Unrealized Losses on Cash Flow Hedges [Member]
Accumulated other comprehensive income (loss), beginning balance	(43)	(287)	(618)
Other comprehensive income (loss) before reclassifications, net of tax	(257)	(53)	(38)
Amounts reclassified from accumulated other comprehensive income, net of tax	0	297	369
Net other comprehensive income (loss)	(257)	244	331
Accumulated other comprehensive income (loss), ending balance	(300)	(43)	(287)
Pension Benefit Adjustment [Member]
Accumulated other comprehensive income (loss), beginning balance	(10,707)	(12,744)	(4,136)
Other comprehensive income (loss) before reclassifications, net of tax	(2,588)	1,102	(8,933)
Amounts reclassified from accumulated other comprehensive income, net of tax	663	935	325
Net other comprehensive income (loss)	(1,925)	2,037	(8,608)
Accumulated other comprehensive income (loss), ending balance	(12,632)	(10,707)	(12,744)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss), beginning balance	(9,699)	(8,809)	(1,553)
Other comprehensive income (loss) before reclassifications, net of tax	(10,721)	(2,122)	(7,950)
Amounts reclassified from accumulated other comprehensive income, net of tax	663	1,232	694
Net other comprehensive income (loss)	(10,058)	(890)	(7,256)
Accumulated other comprehensive income (loss), ending balance	$ (19,757)	$ (9,699)	$ (8,809)

Earnings Per Common Share (Deta

Earnings Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income	$ 12,162	$ 12,327	$ 11,057	$ 10,935	$ 10,744	$ 10,208	$ 11,503	$ 11,010	$ 46,481	$ 43,465	$ 40,824
Less dividends and undistributed earnings allocated to participating securities									(97)	(126)	(152)
Net income applicable to common shareholders									$ 46,384	$ 43,339	$ 40,672
Weighted average common shares outstanding - basic	17,142,000	17,090,000	17,067,000	17,023,000	17,004,000	16,939,000	16,811,000	16,759,000	17,081,000	16,879,000	16,689,000
Basic earnings per common share (in dollars per share)	$ 0.71	$ 0.72	$ 0.65	$ 0.64	$ 0.63	$ 0.60	$ 0.68	$ 0.65	$ 2.72	$ 2.57	$ 2.44
Less dividends and undistributed earnings allocated to participating securities									$ (97)	$ (126)	$ (151)
Net income applicable to common shareholders									$ 46,384	$ 43,339	$ 40,673
Dilutive effect of common stock equivalents (in shares)									127,000	188,000	183,000
Weighted average common shares outstanding - diluted (in shares)	17,245,000	17,203,000	17,194,000	17,157,000	17,167,000	17,102,000	16,989,000	16,939,000	17,208,000	17,067,000	16,872,000
Diluted earnings per common share (in dollars per share)	$ 0.70	$ 0.72	$ 0.64	$ 0.64	$ 0.62	$ 0.60	$ 0.68	$ 0.65	$ 2.70	$ 2.54	$ 2.41
Antidilutive common stock equivalents									59,158	34,850	59,234

Commitments and Contingencie130

Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Line Items]
Standby letters of credit extension period	1 year
Operating leases rental expense	$ 4,000	$ 3,500	$ 3,100
Unpaid principal balance of loans repurchased	524	534
Reserve for loans repurchases	$ 180	180
Minimum [Member]
Commitments and Contingencies Disclosure [Line Items]
Lease expiration period	3 months
Lease expiration period, renewal option	3 months
Maximum [Member]
Commitments and Contingencies Disclosure [Line Items]
Lease expiration period	24 years
Lease expiration period, renewal option	5 years
Commitments to Extend Credit on Standby Letters of Credit [Member] | Commitments to Extend Credit [Member]
Commitments and Contingencies Disclosure [Line Items]
Contract Amount	$ 6,250	$ 5,629

Commitments and Contingencie131

Commitments and Contingencies (Financial Instruments with Off Balance Sheet Risk) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Interest rate lock commitments [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	$ 49,502	$ 49,712
Commitments to sell mortgage loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	78,896	87,498
Interest rate swaps with customers [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	428,723	302,142
Mirror swaps with counterparties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	428,723	302,142
Risk participation-in agreement [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	28,460	21,474
Interest rate swaps [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Notional amount	60,000	0
Commitments to Extend Credit [Member] | Commitments to extend credit on commerical loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract Amount	430,710	360,795
Commitments to Extend Credit [Member] | Commitments to extend credit on home equity lines [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract Amount	232,375	219,427
Commitments to Extend Credit [Member] | Commitments to extend credit on other loans [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract Amount	49,708	44,164
Commitments to Extend Credit [Member] | Commitments to Extend Credit on Standby Letters of Credit [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contract Amount	$ 6,250	$ 5,629

Commitments and Contingencie132

Commitments and Contingencies (Schedule of Future Minimum Operating Lease Payments) (Details) $ in Thousands	Dec. 31, 2016USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Future Minimum Payments, Next Twelve Months	$ 3,448
Future Minimum Payments, Year Two	3,163
Future Minimum Payments, Year Three	2,889
Future Minimum Payments, Year Four	2,210
Future Minimum Payments, Year Five	1,914
Future Minimum Payments, Thereafter	25,148
Total minimum lease payments	$ 38,772

Parent Company Financial Sta133

Parent Company Financial Statements (Balance Sheet) (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014	Dec. 31, 2013
Assets:
Interest-bearing balances due from banks	$ 60,300		$ 48,200
Other assets	62,484		59,365
Total assets	4,381,115		3,771,604		$ 3,586,874
Liabilities:
Junior subordinated debentures	22,681		22,681
Contingent consideration liability	2,047	[1]	2,945	[1]	0
Other liabilities	54,948		60,307
Total liabilities	3,990,311		3,396,216
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares at December 31, 2016 and 30,000,000 at December 31, 2015; issued and outstanding 17,170,820 shares at December 31, 2016 and 17,019,578 shares at December 31, 2015	1,073		1,064
Paid-in capital	115,123		110,949
Retained earnings	294,365		273,074
Accumulated other comprehensive loss	(19,757)		(9,699)
Total shareholders’ equity	390,804		375,388		$ 346,279	$ 329,646
Total liabilities and shareholders’ equity	$ 4,381,115		$ 3,771,604
Common stock, par value (in dollars per share)	$ 0.0625		$ 0.0625
Common stock, shares authorized (in shares)	60,000,000		30,000,000
Common stock, shares issued (in shares)	17,170,820		17,019,578
Common stock, shares outstanding (in shares)	17,170,820		17,019,578
Parent Company [Member]
Assets:
Cash on deposit with bank subsidiary	$ 1,743		$ 3,169
Interest-bearing balances due from banks	0		0
Investment in subsidiaries at equity value	413,613		398,520
Dividends receivable from subsidiaries	6,518		5,082
Other assets	332		377
Total assets	422,206		407,148
Liabilities:
Junior subordinated debentures	22,681		22,681
Dividends payable	6,628		6,075
Contingent consideration liability	2,047		2,945
Other liabilities	46		59
Total liabilities	31,402		31,760
Shareholders’ Equity:
Common stock of $.0625 par value; authorized 60,000,000 shares at December 31, 2016 and 30,000,000 at December 31, 2015; issued and outstanding 17,170,820 shares at December 31, 2016 and 17,019,578 shares at December 31, 2015	1,073		1,064
Paid-in capital	115,123		110,949
Retained earnings	294,365		273,074
Accumulated other comprehensive loss	(19,757)		(9,699)
Total shareholders’ equity	390,804		375,388
Total liabilities and shareholders’ equity	$ 422,206		$ 407,148
[1]	The contingent consideration liability is included in other liabilities in the Consolidated Balance Sheets.

Parent Company Financial Sta134

Parent Company Financial Statements (Statement of Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Expenses:
Interest on junior subordinated debentures									$ 491	$ 871	$ 964
Legal and professional fees									2,579	2,741	2,336
Acquisition related expenses									0	989	0
Change in fair value of contingent consideration									(898)	41	0
Income before income taxes	$ 18,035	$ 18,190	$ 16,210	$ 16,419	$ 16,090	$ 15,172	$ 16,890	$ 16,191	68,854	64,343	59,823
Income tax benefit	(5,873)	(5,863)	(5,153)	(5,484)	(5,346)	(4,964)	(5,387)	(5,181)	(22,373)	(20,878)	(18,999)
Net income	$ 12,162	$ 12,327	$ 11,057	$ 10,935	$ 10,744	$ 10,208	$ 11,503	$ 11,010	46,481	43,465	40,824
Parent Company [Member]
Income:
Dividends from subsidiaries									24,542	23,399	20,116
Other income									15	13	13
Total income									24,557	23,412	20,129
Expenses:
Interest on junior subordinated debentures									491	871	964
Legal and professional fees									98	134	96
Acquisition related expenses									0	308	0
Change in fair value of contingent consideration									(898)	41	0
Other									282	254	253
Total expenses									(27)	1,608	1,313
Income before income taxes									24,584	21,804	18,816
Income tax benefit									(15)	557	454
Income before equity in undistributed earnings of subsidiaries									24,569	22,361	19,270
Equity in undistributed earnings of subsidiaries									21,912	21,104	21,554
Net income									$ 46,481	$ 43,465	$ 40,824

Parent Company Financial Sta135

Parent Company Financial Statements (Statements of Cash Flows) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income	$ 12,162	$ 12,327	$ 11,057	$ 10,935	$ 10,744	$ 10,208	$ 11,503	$ 11,010	$ 46,481	$ 43,465	$ 40,824
Adjustments to reconcile net income to net cash provided by operating activities:
Decrease (increase) in other assets									(630)	4,458	8,250
Change in fair value of contingent consideration									(898)	41	0
Net cash provided by operating activities									58,733	51,566	2,648
Cash flows from investing activities:
Cash used in business combination, net of cash acquired									0	(1,671)	0
Net cash used in investing activities									(625,377)	(165,885)	(357,372)
Cash flows from financing activities:
Proceeds from stock option exercises and issuance of other equity instruments									977	1,563	1,189
Tax benefit from stock option exercises and other equity instruments									1,016	694	578
Cash dividends paid									(24,637)	(22,770)	(19,722)
Net cash provided by financing activities									576,810	131,600	349,757
Net increase (decrease) in cash and cash equivalents									10,166	17,281	(4,967)
Cash and cash equivalents at beginning of year				97,631				80,350	97,631	80,350	85,317
Cash and cash equivalents at end of year	107,797				97,631				107,797	97,631	80,350
Parent Company [Member]
Cash flows from operating activities:
Net income									46,481	43,465	40,824
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed earnings of subsidiary									(21,912)	(21,104)	(21,554)
(Increase) decrease in dividend receivable									(1,436)	19	(495)
Decrease (increase) in other assets									45	(67)	183
(Decrease) increase in accrued expenses and other liabilities									(12)	2,425	(516)
Change in fair value of contingent consideration									(898)	41	0
Other, net									(1,051)	(3,363)	(245)
Net cash provided by operating activities									21,217	21,416	18,197
Cash flows from investing activities:
Cash used in business combination, net of cash acquired									0	(1,671)	0
Net cash used in investing activities									0	(1,671)	0
Cash flows from financing activities:
Proceeds from stock option exercises and issuance of other equity instruments									978	1,563	1,189
Tax benefit from stock option exercises and other equity instruments									1,016	694	578
Cash dividends paid									(24,637)	(22,770)	(19,722)
Net cash provided by financing activities									(22,643)	(20,513)	(17,955)
Net increase (decrease) in cash and cash equivalents									(1,426)	(768)	242
Cash and cash equivalents at beginning of year				$ 3,169				$ 3,937	3,169	3,937	3,695
Cash and cash equivalents at end of year	$ 1,743				$ 3,169				$ 1,743	$ 3,169	$ 3,937

Selected Quarterly Consolida136

Selected Quarterly Consolidated Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Interest and dividend income	$ 35,055	$ 33,256	$ 32,190	$ 32,969	$ 31,477	$ 31,526	$ 31,510	$ 31,237	$ 133,470	$ 125,750	$ 121,117
Interest expense	6,467	5,877	5,414	5,234	5,222	5,529	5,482	5,535	22,992	21,768	21,612
Net interest income	28,588	27,379	26,776	27,735	26,255	25,997	26,028	25,702	110,478	103,982	99,505
Provision for loan losses	2,900	1,800	450	500	750	200	100	0	5,650	1,050	1,850
Net interest income after provision for loan losses	25,688	25,579	26,326	27,235	25,505	25,797	25,928	25,702	104,828	102,932	97,655
Noninterest income	17,320	17,261	15,914	14,634	15,146	13,913	15,261	14,020	65,129	58,340	59,015
Noninterest expense	24,973	24,650	26,030	25,450	24,561	24,538	24,299	23,531	101,103	96,929	96,847
Income before income taxes	18,035	18,190	16,210	16,419	16,090	15,172	16,890	16,191	68,854	64,343	59,823
Income tax expense	5,873	5,863	5,153	5,484	5,346	4,964	5,387	5,181	22,373	20,878	18,999
Net income	$ 12,162	$ 12,327	$ 11,057	$ 10,935	$ 10,744	$ 10,208	$ 11,503	$ 11,010	$ 46,481	$ 43,465	$ 40,824
Weighted average common shares outstanding - basic	17,142	17,090	17,067	17,023	17,004	16,939	16,811	16,759	17,081	16,879	16,689
Weighted average common shares outstanding - diluted	17,245	17,203	17,194	17,157	17,167	17,102	16,989	16,939	17,208	17,067	16,872
Basic earnings per common share (in dollars per share)	$ 0.71	$ 0.72	$ 0.65	$ 0.64	$ 0.63	$ 0.60	$ 0.68	$ 0.65	$ 2.72	$ 2.57	$ 2.44
Diluted earnings per common share (in dollars per share)	0.70	0.72	0.64	0.64	0.62	0.60	0.68	0.65	2.70	2.54	2.41
Cash dividends declared per share (in dollars per share)	$ 0.37	$ 0.37	$ 0.36	$ 0.36	$ 0.34	$ 0.34	$ 0.34	$ 0.34	$ 1.46	$ 1.36	$ 1.22

Sale of Business Line (Narrativ

Sale of Business Line (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Sale of Business Line [Abstract]
Gain on sale of business line, before tax	$ 0	$ 0	$ 6,265
Gain on sale of business line, after tax			$ 4,000
Earnings per share impact, gain on sale of business line			$ 0.24
Divestiture costs, before tax			$ 355
Divestiture costs, after tax			$ 227
Earnings per share impact, divestiture costs			$ 0.01
Net proceeds from the sale of business line	0	0	$ 7,205
Deferred revenue from sale of business line			900
Merchant referral revenue earned	180	$ 180	$ 180
Deferred merchant referral revenue remaining	$ 360