Enterprise Bancorp (EBTC) 10-Q 6 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	May. 02, 2016
Document and Entity Information [Abstract]
Entity Registrant Name	ENTERPRISE BANCORP INC /MA/
Entity Central Index Key	1,018,399
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding		10,474,757

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Cash and cash equivalents:
Cash and due from banks	$ 34,018	$ 32,318
Interest-earning deposits	24,912	19,177
Total cash and cash equivalents	58,930	51,495
Investment securities at fair value	304,946	300,358
Federal Home Loan Bank stock	2,793	3,050
Loans held for sale	770	1,709
Loans, less allowance for loan losses of $29,910 at March 31, 2016 and $29,008 at December 31, 2015	1,834,782	1,830,954
Premises and equipment, net	31,984	30,553
Accrued interest receivable	8,393	7,790
Deferred income taxes, net	12,962	14,111
Bank-owned life insurance	28,209	28,018
Prepaid income taxes	0	57
Prepaid expenses and other assets	15,207	11,780
Goodwill	5,656	5,656
Total assets	2,304,632	2,285,531
Liabilities
Deposits	2,087,737	2,018,148
Borrowed Funds	671	53,671
Subordinated debt	14,825	14,822
Accrued expenses and other liabilities	13,497	18,287
Income taxes payable	1,551	0
Accrued interest payable	266	276
Total liabilities	$ 2,118,547	$ 2,105,204
Commitments and Contingencies
Stockholders' Equity
Preferred stock, $0.01 par value per share; 1,000,000 shares authorized; no shares issued	$ 0	$ 0
Common stock $0.01 par value per share; 20,000,000 shares authorized; 10,473,738 shares issued and outstanding at March 31, 2016 (including 155,421 shares of unvested participating restricted awards), 10,377,787 shares issued and outstanding at December 31, 2015 (including 144,717 shares of unvested participating restricted awards)	105	104
Additional paid-in-capital	61,927	61,008
Retained earnings	119,904	116,941
Accumulated other comprehensive income	4,149	2,274
Total stockholders' equity	186,085	180,327
Total liabilities and stockholders' equity	$ 2,304,632	$ 2,285,531

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Allowance for loan losses	$ 29,910	$ 29,008
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	10,473,738	10,377,787
Common stock, shares outstanding	10,473,738	10,377,787
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Unvested participating restricted stock awards	155,421	144,717

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Interest and dividend income:
Loans and loans held for sale	$ 20,881	$ 18,582
Investment securities	1,540	1,225
Other interest-earning assets	44	32
Total interest and dividend income	22,465	19,839
Interest expense:
Deposits	1,088	992
Borrowed funds	63	21
Subordinated debt	231	372
Total interest expense	1,382	1,385
Net interest income	21,083	18,454
Provision for loan losses	850	625
Net interest income after provision for loan losses	20,233	17,829
Non-interest income:
Investment advisory fees	1,104	1,177
Deposit and interchange fees	1,242	1,154
Income on bank-owned life insurance,net	191	100
Net gains on sales of investment securities	2	900
Gains on sales of loans	89	156
Other income	578	538
Total non-interest income	3,206	4,025
Non-interest expense:
Salaries and employee benefits	10,485	9,581
Occupancy and equipment expenses	1,813	1,960
Technology and telecommunications expenses	1,423	1,417
Advertising and public relations expenses	679	730
Audit, legal and other professional fees	488	359
Deposit insurance premiums	326	293
Supplies and postage expenses	229	258
Investment advisory and custodial expenses	89	46
Other operating expenses	1,337	1,566
Total non-interest expense	16,869	16,210
Income before income taxes	6,570	5,644
Provision for income taxes	2,257	2,024
Net income	$ 4,313	$ 3,620
Basic earnings per share	$ 0.41	$ 0.35
Diluted earnings per share	$ 0.41	$ 0.35
Basic weighted average common shares outstanding	10,405,112	10,243,044
Diluted weighted average common shares outstanding	10,471,784	10,310,474

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 4,313	$ 3,620
Other comprehensive income, net of taxes:
Gross change in unrealized holding gains on investments arising during the period	3,026	2,107
Income tax expense	(1,150)	(724)
Net unrealized holding gains, net of tax	1,876	1,383
Less: Reclassification adjustment for net gains included in net income
Net realized gains on sales of securities during the period	2	900
Income tax expense	(1)	(314)
Reclassification adjustment for gains realized, net of tax	1	586
Total other comprehensive income	1,875	797
Comprehensive income	$ 6,188	$ 4,417

Consolidated Statement of Chang

Consolidated Statement of Changes in Stockholders' Equity - 3 months ended Mar. 31, 2016 - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income
Balance, beginning at Dec. 31, 2015	$ 180,327	$ 104	$ 61,008	$ 116,941	$ 2,274
Increase (Decrease) in Stockholders' Equity
Net income	4,313			4,313
Other comprehensive income, net	1,875				1,875
Common stock dividend paid ($0.13 per share)	(1,350)			(1,350)
Common stock issued under dividend reinvestment plan	336	0	336
Common stock issued other	16	0	16
Stock-based compensation, net	423	1	422
Stock options exercised, net	145	0	145
Balance, ending at Mar. 31, 2016	$ 186,085	$ 105	$ 61,927	$ 119,904	$ 4,149

Consolidated Statement of Chan7

Consolidated Statement of Changes in Stockholders' Equity (Parenthetical)	3 Months Ended
	Mar. 31, 2016$ / shares
Statement of Stockholders' Equity [Abstract]
Common stock dividend paid, per share	$ 0.13

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Cash flows from operating activities
Net income	$ 4,313,000	$ 3,620,000
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Provision for loan losses	850,000	625,000
Depreciation and amortization	1,425,000	1,389,000
Stock-based compensation expense	443,000	488,000
Mortgage loans originated for sale	(3,273,000)	(6,729,000)
Proceeds from mortgage loans sold	4,301,000	8,131,000
Net gains on sales of loans	(89,000)	(156,000)
Net gains on sales of OREO	0	(154,000)
Net gains on sales of investments	(2,000)	(900,000)
Income on bank-owned life insurance,net	(191,000)	(100,000)
Changes in:
Accrued interest receivable	(603,000)	(268,000)
Prepaid expenses and other assets	(3,580,000)	6,807,000
Deferred income taxes	0	74,000
Accrued expenses and other liabilities	(662,000)	(228,000)
Subordinated debt issuance costs	3,000	(190,000)
Accrued interest payable	(10,000)	(282,000)
Net cash provided by operating activities	2,925,000	12,127,000
Cash flows from investing activities:
Proceeds from sales of investment securities available for sale	306,000	10,151,000
Net proceeds (purchases) from FHLB capital stock	257,000	(882,000)
Proceeds from maturities, calls and pay-downs of investment securities	4,785,000	6,443,000
Purchase of investment securities	(9,210,000)	(9,877,000)
Net increase in loans	(4,678,000)	(9,459,000)
Additions to premises and equipment, net	(3,006,000)	(786,000)
Proceeds from OREO sales and payments	0	901,000
Proceeds from bank-owned life insurance	405,000	0
Net cash used in investing activities	(11,141,000)	(3,509,000)
Cash flows from financing activities:
Net increase in deposits	69,589,000	96,748,000
Net decrease in borrowed funds	(53,000,000)	(58,000,000)
Repayment of subordinated debt	0	(10,825,000)
Proceeds from issuance of subordinated debt	0	15,000,000
Cash dividends paid	(1,350,000)	(1,279,000)
Proceeds from issuance of common stock	352,000	368,000
Exercise of stock options, net of repurchases for tax withholdings and tax benefit on stock options and restricted stock	60,000	384,000
Net cash provided by financing activities	15,651,000	42,396,000
Net increase in cash and cash equivalents	7,435,000	51,014,000
Cash and cash equivalents at beginning of period	51,495,000	40,146,000	$ 40,146,000
Cash and cash equivalents at end of period	58,930,000	91,160,000	$ 51,495,000
Supplemental financial data:
Cash Paid For: Interest	1,392,000	1,667,000
Cash Paid For: Income Taxes	636,000	587,000
Supplemental schedule of non-cash investing activity:
Net purchases of investment securities not yet settled	$ 100,000	$ 2,237,000

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies (a) Organization of Holding Company and Basis of Presentation The accompanying unaudited consolidated interim financial statements and these notes should be read in conjunction with the December 31, 2015 audited consolidated financial statements and notes thereto contained in the 2015 Annual Report on Form 10-K of Enterprise Bancorp, Inc. (the "Company" or "Enterprise"), a Massachusetts corporation, as filed with the Securities and Exchange Commission (the "SEC") on March 15, 2016 . The Company has not changed its accounting policies from those disclosed in its 2015 Annual Report on Form 10-K. The Company's unaudited consolidated interim financial statements include the accounts of the Company and its wholly owned subsidiary, Enterprise Bank and Trust Company (the "Bank"). The Bank is a Massachusetts trust company organized in 1989. Substantially all of the Company's operations are conducted through the Bank and its subsidiaries. The Bank's subsidiaries include Enterprise Insurance Services, LLC and Enterprise Investment Services, LLC, organized under the laws of the State of Delaware for the purposes of engaging in insurance sales activities and offering non-deposit investment products and services, respectively. In addition, the Bank has the following subsidiaries that are incorporated in the Commonwealth of Massachusetts and classified as security corporations in accordance with applicable Massachusetts General Laws: Enterprise Security Corporation; Enterprise Security Corporation II; and Enterprise Security Corporation III. The security corporations, which hold various types of qualifying securities, are limited to conducting securities investment activities that the Bank itself would be allowed to conduct under applicable laws. The Company has 22 full service branches serving the greater Merrimack Valley and North Central regions of Massachusetts and Southern New Hampshire. The Company also plans to open its second Nashua, NH branch in the second quarter of 2016. Through the Bank and its subsidiaries, the Company offers a range of commercial and consumer loan products, and deposit and cash management services. The Company also offers investment advisory and wealth management, trust and insurance services. The services offered through the Bank and its subsidiaries are managed as one strategic unit and represent the Company's only reportable operating segment. Prior to the end of March 2015, pursuant to the Accounting Standards Codification ("ASC") Topic 810 "Consolidation of Variable Interest Entities," issued by the Financial Accounting Standards Board ("FASB"), the Company carried Junior Subordinated Debentures as a liability on its consolidated financial statements, along with the related interest expense. The debentures were issued by a statutory business trust (the "Trust") created by the Company in March 2000 under the laws of the State of Delaware, and the trust preferred securities issued by the Trust, and the related non-interest expense, were excluded from the Company's consolidated financial statements. In March 2015 , the Company redeemed in full the Junior Subordinated Debentures, which in turn allowed the Trust to redeem in full the trust preferred securities. The Company also dissolved the Trust in April 2015. See Note 6, "Borrowed Funds and Subordinated Debt," below for further information on the Company's subordinated debt. The Federal Deposit Insurance Corporation (the "FDIC") and the Massachusetts Division of Banks (the "Division") have regulatory authority over the Bank. The Bank is also subject to certain regulatory requirements of the Board of Governors of the Federal Reserve System (the "Federal Reserve Board") and, with respect to its New Hampshire branch operations, the New Hampshire Banking Department. The business and operations of the Company are subject to the regulatory oversight of the Federal Reserve Board. The Division also retains supervisory jurisdiction over the Company. The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") for interim financial information and the instructions for Form 10-Q through the rules and interpretive releases of the SEC under federal securities law. In the opinion of management, the accompanying unaudited consolidated interim financial statements reflect all necessary adjustments consisting of normal recurring accruals for a fair presentation. All significant intercompany balances and transactions have been eliminated in the accompanying unaudited consolidated interim financial statements. Certain previous years' amounts in the consolidated financial statements, and notes thereto, have been reclassified to conform to the current year's presentation. Interim results are not necessarily indicative of results to be expected for the entire year. (b) Critical Accounting Estimates In preparing the unaudited consolidated interim financial statements in conformity with GAAP, management is required to exercise judgment in determining many of the methodologies, assumptions and estimates to be utilized. These assumptions and estimates affect the reported values of assets and liabilities as of the balance sheet date and income and expenses for the period then ended. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates should the assumptions and estimates used change over time due to changes in circumstances. Changes in those estimates resulting from continuing change in the economic environment and other factors will be reflected in the financial statements and results of operations in future periods. As discussed in the Company's 2015 Annual Report on Form 10-K, the three most significant areas in which management applies critical assumptions and estimates that are particularly susceptible to change relate to the determination of the allowance for loan losses, impairment review of investment securities and the impairment review of goodwill. Refer to Note 1,"Summary of Significant Accounting Policies," to the Company's consolidated financial statements included in the Company's 2015 Annual Report on Form 10-K for significant accounting policies. The Company has not changed its significant accounting policies from those disclosed in its 2015 Annual Report filed on Form 10-K. (c) Reporting Comprehensive Income Comprehensive income is defined as all changes to stockholders' equity except investments by and distributions to stockholders. Net income is one component of comprehensive income, with other components referred to in the aggregate as other comprehensive income. The Company's only other comprehensive income component is the net unrealized holding gains or losses on investments available-for-sale, net of deferred income taxes. Pursuant to Accounting Standards Update ("ASU") No. 2013-02, Comprehensive Income (Topic 220): Reporting Amounts Reclassified Out of Accumulated Other Comprehensive Income, the Company initially excludes these unrealized holding gains and losses from net income; however, they are later reported as reclassifications out of accumulated other comprehensive income into net income when the securities are sold. When securities are sold, the reclassification of realized gains and losses on available-for-sale securities are included on the Consolidated Statements of Income under the "non-interest income" subheading on the line item "net gains on sales of investment securities" and the related income tax expense is included in the line item "provision for income taxes," both of which are also detailed on the Consolidated Statements of Comprehensive Income under the subheading "reclassification adjustment for net gains included in net income." (d) Restricted Investments As a member of the Federal Home Loan Bank of Boston ("FHLB"), the Company is required to purchase certain levels of FHLB capital stock at par value in association with the Company's borrowing relationship from the FHLB. This stock is classified as a restricted investment and carried at cost, which management believes approximates fair value. FHLB stock represents the only restricted investment held by the Company. In conjunction with the other-than-temporary-impairment ("OTTI") review on available-for-sale investments (See Note 2, "Investments," for additional information), management also regularly reviews its holdings of FHLB stock for OTTI. Based on management's periodic review, the Company has not recorded any OTTI charges on this investment to date. If it was determined that a write-down of FHLB stock was required, impairment would be recognized through a charge to earnings. (e) Income Taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax attributable to differences between the financial statement carrying amounts and the tax basis of assets and liabilities. The deferred tax assets and liabilities are reflected at currently enacted income tax rates applicable to the period in which the deferred tax assets or liabilities are expected to be realized or settled. As changes in tax laws or rates are enacted, deferred tax assets and liabilities will be adjusted accordingly through the provision for income taxes. The Company's policy is to classify interest resulting from underpayment of income taxes as income tax expense in the first period the interest would begin accruing according to the provisions of the relevant tax law. The Company classifies penalties resulting from underpayment of income taxes as income tax expense in the period for which the Company claims or expects to claim an uncertain tax position or in the period in which the Company's judgment changes regarding an uncertain tax position. The income tax provisions will differ from the expense that would result from applying the federal statutory rate to income before taxes, due primarily to the impact of tax exempt interest from certain investment securities, loans and bank-owned life insurance. The Company did not have any unrecognized tax benefits accrued as income tax liabilities or receivables or as deferred tax items at March 31, 2016 . The Company is subject to U.S. federal and state income tax examinations by taxing authorities for the 2012 through 2015 tax years. (f) Subsequent Events Although the Company believes its current capital is adequate to support ongoing operations, on April 21, 2016, the Company commenced a subscription rights offering to the Company’s stockholders, together with a supplemental community offering, with the intention of raising up to $10 million in gross proceeds. The Company has the ability to accept oversubscription requests in the rights offering and/or to facilitate sales of shares to new investors in the community offering resulting in gross proceeds of up to $12 million . All shares sold in the offerings will be sold at a per share price of $21.50 . Subject to early termination or extension at the sole discretion of the Company, the rights offering is scheduled to expire on May 27, 2016 and the supplemental community offering is scheduled to expire on June 10, 2016. The Company intends to use the net proceeds from the offerings to support future asset growth and for various corporate purposes. The Company is using its existing shelf registration statement in connection with the offerings. (g) Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board ("FASB") issued ASU No. 2015-03, Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in this ASU require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this ASU. Entities are required to apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. For public business entities, the amendments are effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption of the amendments is permitted for financial statements that have not been previously issued. The Company early adopted this ASU as of January 1, 2015 in relation to the Company's Fixed-to-Floating Rate Subordinated Notes issued in January 2015. This adoption did not have a material impact on the Company's financial statements or results of operations. In January 2015, the FASB issued Accounting Standards Update (ASU) 2015-01, "Income Statement-Extraordinary and Unusual Items (Subtopic 225-20): Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items." This ASU will align more closely GAAP income statement presentation guidance with International Audit Standards (IAS) 1, Presentation of Financial Statements, which prohibits the presentation and disclosure of extraordinary items. The amendments in this update are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. The adoption of this standard did not have an impact on the Company's financial statements. For information regarding recent accounting pronouncements not yet adopted by the Company, see Item 2, "Management's Discussion and Analysis of Financial Condition and Results of Operations," under the heading "Recent Accounting Pronouncements Not Yet Adopted."

Investments

Investments	3 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Investments	Investments The amortized cost and carrying values of investment securities at the dates specified are summarized as follows: March 31, 2016 (Dollars in thousands) Amortized cost Unrealized gains Unrealized losses Fair Value Federal agency obligations (1) $ 78,640 $ 1,097 $ 19 $ 79,718 Residential federal agency MBS (1) 72,069 844 184 72,729 Commercial federal agency MBS (1) 27,499 286 — 27,785 Municipal securities 97,040 2,928 43 99,925 Corporate bonds 10,284 128 29 10,383 Certificates of deposits (2) 1,943 17 — 1,960 Total fixed income securities 287,475 5,300 275 292,500 Equity investments 10,969 1,879 402 12,446 Total available-for-sale securities, at fair value $ 298,444 $ 7,179 $ 677 $ 304,946 December 31, 2015 (Dollars in thousands) Amortized cost Unrealized gains Unrealized losses Fair Value Federal agency obligations (1) $ 78,626 $ 352 $ 153 $ 78,825 Residential federal agency MBS (1) 75,105 406 648 74,863 Commercial federal agency MBS (1) 23,908 — 363 23,545 Municipal securities 96,189 2,357 35 98,511 Corporate bonds 10,257 44 95 10,206 Certificates of deposits (2) 2,753 — 2 2,751 Total fixed income securities 286,838 3,159 1,296 288,701 Equity investments 10,043 1,966 352 11,657 Total available-for-sale securities, at fair value $ 296,881 $ 5,125 $ 1,648 $ 300,358 __________________________________________ (1) These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae ("FNMA"), Freddie Mac ("FHLMC"), Federal Farm Credit Bank ("FFCB"), or one of several Federal Home Loan Banks, as well as, investments guaranteed by Ginnie Mae ("GNMA"), a wholly-owned government entity. (2) Certificates of deposits ("CDs") represent term deposits issued by banks that are subject to FDIC insurance and purchased on the open market. Included in the residential federal agency MBS category were collateralized mortgage obligations (“CMOs”) totaling $20.0 million and $20.8 million at March 31, 2016 and December 31, 2015 respectively. All of the commercial MBS investments held by the Company were CMOs. At March 31, 2016 , the equity portfolio consisted primarily of investments in a diversified group of mutual funds, with a portion of the portfolio (approximately 16% ) invested in individual common stock of entities in the financial services industry. Net unrealized appreciation and depreciation on investments available-for-sale, net of applicable income taxes, are reflected as a component of accumulated other comprehensive income. The net unrealized gain or loss in the Company's fixed income portfolio fluctuates as market interest rates rise and fall. Due to the fixed rate nature of this portfolio, as market rates fall the value of the portfolio rises, and as market rates rise, the value of the portfolio declines. The unrealized gains or losses on fixed income investments will also decline as the securities approach maturity, or if the issuer is credit impaired. Unrealized gains or losses will be recognized in the statements of income if the securities are sold. However, if an unrealized loss on a fixed income investment is deemed to be other than temporary, the credit loss portion is charged to earnings and the noncredit portion is recognized in accumulated other comprehensive income. The net unrealized gain or loss on equity securities will fluctuate based on changes in the market value of the mutual funds and individual securities held in the portfolio. Unrealized gains or losses will be recognized in the statements of income if the securities are sold. However, if an unrealized loss on an equity security is deemed to be other than temporary prior to a sale, the loss is charged to earnings. Management regularly reviews the portfolio for securities with unrealized losses that are other-than-temporarily impaired. During the three months ended March 31, 2016 and 2015 , the Company did not record any fair value impairment charges on its investments. As of March 31, 2016 , there were a total of 36 investments (fixed income and equity, excluding CDs), with a fair market value of $28.6 million , in an unrealized loss position totaling $677 thousand , including 9 investments in an unrealized loss position totaling $194 thousand that have been temporarily impaired for 12 months or longer. Management attributes these unrealized losses to increases in market yields compared to the yields at the time the investments were purchased by the Company and the impact of market value fluctuations on the equity portion of our portfolio. Management does not consider these investments to be other-than-temporarily impaired at March 31, 2016 , because (1) the decline in market value is not attributable to credit quality for fixed income securities or a fundamental deterioration in the equity fund or issuers, and (2) the Company does not intend to, and it is more likely than not that it will not be required to, sell those investments prior to a market price recovery or maturity. In assessing the Company's investments in federal agency mortgage-backed securities and federal agency obligations, the contractual cash flows of these investments are guaranteed by the respective government sponsored enterprise (FHLMC, FNMA, FFCB, or FHLB) or wholly-owned government corporation (GNMA). Accordingly, it is expected that the securities would not be settled at a price less than the par value of the Company's investments. Management's assessment of other fixed income investments within the portfolio includes reviews of market pricing, ongoing credit quality evaluations, assessment of the investments' materiality, and duration of the investments' unrealized loss position. In addition, the Company utilizes an outside registered investment adviser to manage the corporate and municipal bond portfolios, within prescribed guidelines set by management, and to provide assistance in assessing the credit risk of those portfolios. At March 31, 2016 , the Company's corporate and municipal bond portfolios did not contain any securities below investment grade, as reported by major credit rating agencies. For equities and funds, management's assessment includes the severity of the declines, whether it is unlikely that the security or fund will completely recover its unrealized loss within a reasonable time period and if the equity security or fund exhibits fundamental deterioration. As noted in the table above, a small portion of the fixed income portfolio is also invested in short-term CDs purchased on the open market; none of which were in an unrealized loss position at March 31, 2016 . The contractual maturity distribution at March 31, 2016 of total fixed income investments was as follows: Within One Year After One, But Within Five Years After Five, But Within Ten Years After Ten Years Amortized Cost Yields Amortized Cost Yields Amortized Cost Yields Amortized Cost Yields At amortized cost: Federal agency obligations $ 7,035 0.91 % $ 62,054 1.59 % $ 9,551 2.22 % $ — — % Residential federal agency MBS — — % 3,101 3.17 % 1,242 1.91 % 67,726 2.13 % Commercial federal agency MBS — — % — — % 27,499 2.26 % — — % Municipal securities 6,233 2.31 % 25,813 3.58 % 33,612 3.65 % 31,382 3.85 % Corporate bonds 528 1.33 % 5,175 2.15 % 4,581 2.94 % — — % CDs 993 0.34 % 950 2.13 % — — % — — % Total fixed income securities $ 14,789 1.48 % $ 97,093 2.21 % $ 76,485 2.90 % $ 99,108 2.67 % At fair value: Total fixed income securities $ 14,841 $ 98,726 $ 78,292 $ 100,641 Scheduled contractual maturities shown above may not reflect the actual maturities of the investments. The actual MBS/CMO cash flows likely will be faster than presented above due to prepayments and amortization. Similarly, included in the carrying value of fixed income investments above are callable securities, comprised of municipal securities and corporate bonds totaling $49.4 million , which can be redeemed by the issuer prior to the maturity presented above. Management considers these factors when evaluating the interest rate risk in the Company's asset-liability management program. From time to time, the Company may pledge securities as collateral for deposit account balances of municipal deposit customers, and for borrowing capacity with the FHLB and the Federal Reserve Bank of Boston (the "FRB"). The fair value of securities pledged as collateral for these purposes was $ 290.5 million at March 31, 2016 . See Note 11, "Fair Value Measurements," below for further information regarding the Company's fair value measurements for available-for-sale securities.

Loans

Loans	3 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Loans	Loans The Company specializes in lending to business entities, non-profit organizations, professionals and individuals. The Company's primary lending focus is on the development of high quality commercial relationships achieved through active business development efforts, long-term relationships with established commercial developers, strong community involvement and focused marketing strategies. Loans made to businesses include commercial mortgage loans, construction and land development loans, secured and unsecured commercial loans and lines of credit, and standby letters of credit. The Company also originates equipment lease financing for businesses. Loans made to individuals include conventional residential mortgage loans, home equity loans and lines, residential construction loans on primary and secondary residences, and secured and unsecured personal loans and lines of credit. The Company manages its loan portfolio to avoid concentration by industry and loan size to lessen its credit risk exposure. See Note 4, "Allowance for Loan Losses," for information on the Company's credit risk management, non-accrual, impaired and troubled debt restructured loans and the allowance for loan losses. Major classifications of loans at the periods indicated were as follows: (Dollars in thousands) March 31, December 31, Commercial real estate $ 936,907 $ 936,921 Commercial and industrial 456,436 458,553 Commercial construction 207,214 202,993 Total commercial loans 1,600,557 1,598,467 Residential mortgages 170,585 169,188 Home equity loans and lines 84,665 83,373 Consumer 10,539 10,747 Total retail loans 265,789 263,308 Gross loans 1,866,346 1,861,775 Deferred loan origination fees, net (1,654 ) (1,813 ) Total loans 1,864,692 1,859,962 Allowance for loan losses (29,910 ) (29,008 ) Net loans $ 1,834,782 $ 1,830,954 Loan Categories - Commercial loans: Commercial real estate loans include loans secured by both owner-use and non-owner occupied real estate. These loans are typically secured by a variety of commercial and industrial property types, including one-to-four and multi-family apartment buildings, office or mixed-use facilities, strip shopping centers, or other commercial properties, and are generally guaranteed by the principals of the borrower. Commercial real estate loans generally have repayment periods of approximately fifteen to twenty-five years. Variable interest rate loans have a variety of adjustment terms and underlying interest rate indices, and are generally fixed for an initial period before periodic rate adjustments begin. Commercial and industrial loans include seasonal revolving lines of credit, working capital loans, equipment financing (including equipment leases), and term loans. Also included in commercial and industrial loans are loans partially guaranteed by the U.S. Small Business Administration ("SBA"), and loans under various programs and agencies. Commercial and industrial credits may be unsecured loans and lines to financially strong borrowers, loans secured in whole or in part by real estate unrelated to the principal purpose of the loan or secured by inventories, equipment, or receivables, and are generally guaranteed by the principals of the borrower. Variable rate loans and lines in this portfolio have interest rates that are periodically adjusted, with loans generally having fixed initial periods. Commercial and industrial loans have average repayment periods of one to seven years. Commercial construction loans include the development of residential housing and condominium projects, the development of commercial and industrial use property, and loans for the purchase and improvement of raw land. These loans are secured in whole or in part by underlying real estate collateral and are generally guaranteed by the principals of the borrowers. Construction lenders work to cultivate long-term relationships with established commercial developers. The Company limits the amount of financing provided to any single developer for the construction of properties built on a speculative basis. Funds for construction projects are disbursed as pre-specified stages of construction are completed. Regular site inspections are performed, prior to advancing additional funds, at each construction phase, either by experienced construction lenders on staff or by independent outside inspection companies. Commercial construction loans generally are variable rate loans and lines with interest rates that are periodically adjusted and generally have terms of one to three years. From time to time, the Company participates with other banks in the financing of certain commercial projects. Participating loans with other institutions provide banks the opportunity to retain customer relationships and reduce credit risk exposure among each participating bank, while providing customers with larger credit vehicles than the individual bank might be willing or able to offer independently. In some cases, the Company may act as the lead lender, originating and servicing the loans, but participating out a portion of the funding to other banks. In other cases, the Company may participate in loans originated by other institutions. In each case, the participating bank funds a percentage of the loan commitment and takes on the related pro-rata risk. In each case in which the Company participates in a loan, the rights and obligations of each participating bank are divided proportionately among the participating banks in an amount equal to their share of ownership and with equal priority among all banks. The balances participated out to other institutions are not carried as assets on the Company's financial statements. Loans originated by other banks in which the Company is a participating institution are carried in the loan portfolio at the Company's pro rata share of ownership. The Company performs an independent credit analysis of each commitment and a review of the participating institution prior to participation in the loan. Loans originated by other banks in which the Company is a participating institution amounted to $59.6 million at March 31, 2016 and $62.3 million at December 31, 2015 . Standby letters of credit are conditional commitments issued by the Company to guarantee the financial obligation or performance of a customer to a third party. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. If the letter of credit is drawn upon, a loan is created for the customer, generally a commercial loan, with the same criteria associated with similar commercial loans. - Residential loans: Enterprise originates conventional mortgage loans on one-to-four family residential properties. These properties may serve as the borrower's primary residence, or be vacation homes or investment properties. Loan to value limits vary, generally from 75% for multi-family, owner occupied properties, up to 97% for single family, owner-occupied properties, with mortgage insurance coverage required for loan-to-value ratios greater than 80% based on program parameters. In addition, financing is provided for the construction of owner-occupied primary and secondary residences. Residential mortgage loans may have terms of up to 30 years at either fixed or adjustable rates of interest. Fixed and adjustable rate residential mortgage loans are generally originated using secondary market underwriting and documentation standards. Depending on the current interest rate environment, management projections of future interest rates and the overall asset-liability management program of the Company, management may elect to sell those fixed and adjustable rate residential mortgage loans which are eligible for sale in the secondary market, or hold some or all of this residential loan production for the Company's portfolio. Mortgage loans are generally not pooled for sale, but instead sold on an individual basis. The Company may retain or sell the servicing when selling the loans. Loans sold are subject to standard secondary market underwriting and eligibility representations and warranties over the life of the loan and are subject to an early payment default period covering the first four payments for certain loan sales. Loans classified as held for sale are carried as a separate line item on the balance sheet. - Home equity loans and lines of credit: Home equity term loans are originated for one-to-four family residential properties with maximum original loan to value ratios generally up to 80% of the assessed or appraised value of the property securing the loan. Home equity loan payments consist of monthly principal and interest based on amortization ranging from three to fifteen years. The rates may also be fixed for three to fifteen years. The Company originates home equity revolving lines of credit for one-to-four family residential properties with maximum original loan to value ratios generally up to 80% of the appraised value of the property securing the loan. Home equity lines generally have interest rates that adjust monthly based on changes in the Prime Rate, although minimum rates may be applicable. Some home equity line rates may be fixed for a period of time and then adjusted monthly thereafter. The payment schedule for home equity lines requires interest only payments for the first ten years of the lines. Generally at the end of ten years, the line may be frozen to future advances, and principal plus interest payments are collected over a fifteen -year amortization schedule or, for eligible borrowers meeting certain requirements, the line availability may be extended for an additional interest only period. - Consumer loans: Consumer loans consist primarily of secured or unsecured personal loans, loans under energy efficiency financing programs in conjunction with Massachusetts public utilities, and overdraft protection lines on checking accounts extended to individual customers. The aggregate amount of overdrawn deposit accounts are reclassified as loan balances. Loans serviced for others At March 31, 2016 and December 31, 2015 , the Company was servicing residential mortgage loans owned by investors amounting to $18.2 million and $18.5 million , respectively. Additionally, the Company was servicing commercial loans participated out to various other institutions amounting to $53.1 million and $52.7 million at March 31, 2016 and December 31, 2015 , respectively. See the discussion above for further information regarding commercial participations. Loans serving as collateral Loans designated as qualified collateral and pledged to the FHLB for borrowing capacity are summarized below: (Dollars in thousands) March 31, December 31, Commercial real estate $ 277,056 $ 281,802 Residential mortgages 122,744 118,855 Home equity 13,349 13,972 Total loans pledged to FHLB $ 413,149 $ 414,629

Allowance For Loan Loss

Allowance For Loan Loss	3 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Allowance for Loan Loss	Allowance for Loan Losses While the Company seeks to manage its loan portfolio to avoid concentration by industry and loan size to lessen its credit risk exposure, inherent in the lending process is the risk of loss due to customer non-payment, or "credit risk." The Company endeavors to minimize this risk through sound underwriting practices and the risk management function; however, management recognizes that loan losses will occur and that the amount of these losses will fluctuate depending on the risk characteristics of the loan portfolio and economic conditions. The allowance for loan losses is an estimate of probable credit risk inherent in the loan portfolio as of the specified balance sheet dates. The Company maintains the allowance at a level that it deems adequate to absorb all reasonably anticipated probable losses from specifically known and other credit risks associated with the portfolio. In making its assessment on the adequacy of the allowance, management considers several quantitative and qualitative factors that could have an effect on the credit quality of the portfolio, including individual assessment of larger and high risk credits, delinquency trends and the level of non-performing loans, impaired and restructured loans, net charge-offs, the growth and composition of the loan portfolio, expansion in the geographic market area, the experience level of lenders and changes in underwriting criteria, and the strength of the local and national economies, among other factors. Allowance for probable loan losses methodology On a quarterly basis, management prepares an estimate of the allowance necessary to cover estimated probable credit losses. The Company uses a systematic methodology to measure the amount of estimated loan loss exposure inherent in the portfolio for purposes of establishing a sufficient allowance for loan losses. The methodology makes use of specific reserves for loans individually evaluated and deemed impaired, and general reserves for larger groups of homogeneous loans, which are collectively evaluated relying on a combination of qualitative and quantitative factors that may affect credit quality of the pool. There have been no material changes to the Company's underwriting practices, credit risk management system, or to the allowance assessment methodology used to estimate loan loss exposure as reported in the 2015 Annual Report on Form 10-K. Refer to heading "Allowance for probable loan losses methodology" contained in Note 4 "Allowance For Loan Losses," to the Company's consolidated financial statements contained in the 2015 Annual Report on Form 10-K for further discussion of management's methodology used to estimate the loan loss exposure inherent in the portfolio for purposes of establishing a sufficient allowance. The balances of loans as of March 31, 2016 by segment and evaluation method are summarized as follows: (Dollars in thousands) Loans individually evaluated for impairment Loans collectively evaluated for impairment Total Loans Commercial real estate $ 9,926 $ 926,981 $ 936,907 Commercial and industrial 7,853 448,583 456,436 Commercial construction 2,989 204,225 207,214 Residential 307 170,278 170,585 Home equity 309 84,356 84,665 Consumer 21 10,518 10,539 Deferred Fees — (1,654 ) (1,654 ) Total loans $ 21,405 $ 1,843,287 $ 1,864,692 The balances of loans as of December 31, 2015 by segment and evaluation method are summarized as follows: (Dollars in thousands) Loans individually evaluated for impairment Loans collectively evaluated for impairment Total Loans Commercial real estate $ 12,287 $ 924,634 $ 936,921 Commercial and industrial 7,810 450,743 458,553 Commercial construction 3,032 199,961 202,993 Residential 366 168,822 169,188 Home equity 169 83,204 83,373 Consumer 24 10,723 10,747 Deferred Fees — (1,813 ) (1,813 ) Total loans $ 23,688 $ 1,836,274 $ 1,859,962 Credit quality indicators Early detection of credit issues is critical to minimize credit losses. Accordingly, management regularly monitors internal credit quality indicators such as the risk classification of individual loans, adversely classified loans, past due and non-accrual loans, impaired and restructured loans, and the level of foreclosure activity, as well as trends in the general levels of these indicators. However, despite prudent loan underwriting and ongoing credit risk management, adverse changes within the Company's market area or deterioration in the local, regional or national economic conditions could negatively impact the portfolio's credit risk profile and the Company's asset quality in the future. Adversely classified loans The Company's loan risk rating system classifies loans depending on risk of loss characteristics. The classifications range from "substantially risk free" for the highest quality loans and loans that are secured by cash collateral, through a satisfactory range of "minimal," "moderate," "better than average," and "average" risk, to the regulatory problem-asset classifications of "criticized," for loans that may need additional monitoring, and the more severe adverse classifications of "substandard," "doubtful," and "loss" based on criteria established under banking regulations. Loans classified as substandard include those loans characterized by the distinct possibility that the Company will sustain some loss if deficiencies are not corrected. These loans are inadequately protected by the sound net worth and paying capacity of the borrower; repayment has become increasingly reliant on collateral liquidation or reliance on guarantees; credit weaknesses are well-defined; and borrower cash flow is insufficient to meet required debt service specified in loan terms and to meet other obligations, such as trade debt and tax payments. Loans classified as doubtful have all the weaknesses inherent in a substandard rated loan with the added characteristic that the weaknesses make collection or full payment from liquidation, on the basis of currently existing facts, conditions, and values, highly questionable and improbable. The probability of loss is extremely high, but because of certain important and reasonably specific pending factors which may work to the advantage and strengthening of the loan, its classification as an estimated loss is deferred until more exact status may be determined. Loans classified as loss are generally considered uncollectible at present, although long-term recovery of part or all of loan proceeds may be possible. These "loss" loans would require a specific loss reserve or charge-off. Adversely classified loans may be accruing or in non-accrual status and may be additionally designated as impaired or restructured, or some combination thereof. Loans which are evaluated to be of weaker credit quality are reviewed on a more frequent basis by management. The following tables present the Company's credit risk profile for each class of loan in its portfolio by internally assigned risk rating category at the periods indicated. March 31, 2016 Adversely Classified Not Adversely (Dollars in thousands) Substandard Doubtful Loss Classified Gross Loans Commercial real estate $ 11,586 $ — $ — $ 925,321 $ 936,907 Commercial and industrial 9,100 42 3 447,291 456,436 Commercial construction 1,734 — — 205,480 207,214 Residential 1,213 — — 169,372 170,585 Home equity 644 — — 84,021 84,665 Consumer 37 11 — 10,491 10,539 Total gross loans $ 24,314 $ 53 $ 3 $ 1,841,976 $ 1,866,346 December 31, 2015 Adversely Classified Not Adversely (Dollars in thousands) Substandard Doubtful Loss Classified Gross Loans Commercial real estate $ 12,487 $ — $ — $ 924,434 $ 936,921 Commercial and industrial 8,670 — 3 449,880 458,553 Commercial construction 1,776 — — 201,217 202,993 Residential 1,278 — — 167,910 169,188 Home equity 503 — 5 82,865 83,373 Consumer 38 11 — 10,698 10,747 Total gross loans $ 24,752 $ 11 $ 8 $ 1,837,004 $ 1,861,775 Total adversely classified loans amounted to 1.31% of total loans at March 31, 2016 , as compared to 1.33% at December 31, 2015 . At March 31, 2016 , as compared to December 31, 2015 , adversely classified balances decreased, due primarily to several larger commercial loan payoffs and principal payments, partially offset by additional credit downgrades during the period. Past due and non-accrual loans Loans on which the accrual of interest has been discontinued are designated as non-accrual and are credit downgraded to one of the adversely classified categories noted above. Accrual of interest on loans is generally discontinued when a loan becomes contractually past due, with respect to interest or principal, by 90 days, or when reasonable doubt exists as to the full and timely collection of interest or principal. When a loan is placed on non-accrual status, all interest previously accrued but not collected is reversed against current period interest income. Interest payments received on loans in a non-accrual status are generally applied to principal on the books of the Company. Interest accruals are resumed on such loans only when payments are brought current and have remained current for a period of 180 days and when, in the judgment of management, the collectability of both principal and interest is reasonably assured. Additionally, deposit accounts overdrawn for 90 or more days are included in the consumer non-accrual balances below. The following tables present age analysis of past due loans as of the dates indicated. Balance at March 31, 2016 (Dollars in thousands) Loans 30-59 Days Past Due Loans 60-89 Days Past Due Loans 90 or More Days Past Due (non- accrual) Total Past Due Loans Current Loans Gross Loans Commercial real estate $ 4,665 $ 398 $ 6,188 $ 11,251 $ 925,656 $ 936,907 Commercial and industrial 833 238 4,106 5,177 451,259 456,436 Commercial construction 175 — 213 388 206,826 207,214 Residential — 553 307 860 169,725 170,585 Home equity — — 424 424 84,241 84,665 Consumer 7 19 26 52 10,487 10,539 Total gross loans $ 5,680 $ 1,208 $ 11,264 $ 18,152 $ 1,848,194 $ 1,866,346 Balance at December 31, 2015 (Dollars in thousands) Loans 30-59 Days Past Due Loans 60-89 Days Past Due Loans 90 or More Days Past Due (non- accrual) Total Past Due Loans Current Loans Gross Loans Commercial real estate $ 1,124 $ 1,140 $ 8,506 $ 10,770 $ 926,151 $ 936,921 Commercial and industrial 1,218 691 4,323 6,232 452,321 458,553 Commercial construction 581 — 335 916 202,077 202,993 Residential 250 180 366 796 168,392 169,188 Home equity 622 — 288 910 82,463 83,373 Consumer 35 10 27 72 10,675 10,747 Total gross loans $ 3,830 $ 2,021 $ 13,845 $ 19,696 $ 1,842,079 $ 1,861,775 At March 31, 2016 and March 31, 2015 , all loans 90 days or more past due were carried as non-accrual. Non-accrual loans which were not adversely classified amounted to $337 thousand at March 31, 2016 and $402 thousand at December 31, 2015 . These balances primarily represented the guaranteed portions of non-performing SBA loans. The majority of the non-accrual loan balances were also carried as impaired loans during the periods noted, and are discussed further below. The ratio of non-accrual loans to total loans amounted to 0.60% at March 31, 2016 , 0.74% at December 31, 2015 , and 1.07% at March 31, 2015 . Non-accrual loan balances decreased due primarily to several larger commercial loan payoffs and principal payments, partially offset by additional loans added to non-accrual status during the period. The increase in loans 30 - 59 days past due occurred within the commercial real estate portfolio at March 31, 2016 , with the majority of these loans having subsequent payments made by mid-April. The Company's obligation to fulfill the additional funding commitments on non-accrual loans is generally contingent on the borrower's compliance with the terms of the credit agreement. If the borrower is not in compliance, additional funding commitments may or may not be made at the Company's discretion. At March 31, 2016 , there were no additional funding commitments for loans on non-accrual status. Impaired loans Impaired loans are individually significant loans for which management considers it probable that not all amounts due (principal and interest) in accordance with the original contractual terms will be collected. The majority of impaired loans are included within the non-accrual balances; however, not every loan on non-accrual status has been designated as impaired. Impaired loans include loans that have been modified in a troubled debt restructuring (or "TDR," see below). Impaired loans exclude large groups of smaller-balance homogeneous loans, such as residential mortgage loans and consumer loans, which are collectively evaluated for impairment, and loans that are measured at fair value, unless the loan is amended in a TDR. Management does not set any minimum delay of payments as a factor in reviewing for impaired classification. Management considers the individual payment status, net worth and earnings potential of the borrower, and the value and cash flow of the collateral as factors to determine if a loan will be paid in accordance with its contractual terms. An impaired or TDR loan classification will be considered for upgrade based on the borrower's sustained performance over time and their improving financial condition. Consistent with the criteria for returning non-accrual loans to accrual status, the borrower must demonstrate the ability to continue to service the loan in accordance with the original or modified terms and, in the judgment of management, the collectability of the remaining balances, both principal and interest, are reasonably assured. In the case of TDR loans having had a modified interest rate, that rate must be at, or greater than, a market rate for a similar credit at the time of modification for an upgrade to be considered. Impaired loans are individually evaluated for credit loss and a specific allowance reserve is assigned for the amount of the estimated probable credit loss. Refer to heading "Allowance for probable loan losses methodology" contained in Note 4 "Allowance For Loan Losses," to the Company's consolidated financial statements contained in the 2015 Annual Report on Form 10-K for further discussion of management's methodology used to estimate specific reserves for impaired loans. The carrying value of impaired loans amounted to $21.4 million and $23.7 million at March 31, 2016 and December 31, 2015 , respectively. Total accruing impaired loans amounted to $10.3 million and $10.1 million at March 31, 2016 and December 31, 2015 , respectively, while non-accrual impaired loans amounted to $11.1 million and $13.6 million as of March 31, 2016 and December 31, 2015 , respectively. The decrease was due primarily to the several larger commercial loan payoffs and principal payments discussed above. However, in the current period, the credit ratings of three larger commercial relationships were downgraded to criticized or adverse risk-ratings, based on a review of their individual business circumstances, including one commercial and industrial loan designated as impaired requiring additional specific reserves as of March 31, 2016 . The following tables set forth the recorded investment in impaired loans and the related specific allowance allocated as of the dates indicated. Balance at March 31, 2016 (Dollars in thousands) Unpaid contractual principal balance Total recorded investment in impaired loans Recorded investment with no allowance Recorded investment with allowance Related specific allowance Commercial real estate $ 11,810 $ 9,926 $ 9,165 $ 761 $ 179 Commercial and industrial 9,932 7,853 4,615 3,238 1,420 Commercial construction 3,024 2,989 1,552 1,437 488 Residential 395 307 307 — — Home equity 450 309 309 — — Consumer 23 21 — 21 21 Total $ 25,634 $ 21,405 $ 15,948 $ 5,457 $ 2,108 Balance at December 31, 2015 (Dollars in thousands) Unpaid contractual principal balance Total recorded investment in impaired loans Recorded investment with no allowance Recorded investment with allowance Related specific allowance Commercial real estate $ 14,903 $ 12,287 $ 11,734 $ 553 $ 186 Commercial and industrial 9,816 7,810 5,253 2,557 1,078 Commercial construction 3,147 3,032 1,583 1,449 499 Residential 453 366 366 — — Home equity 308 169 164 5 5 Consumer 25 24 — 24 24 Total $ 28,652 $ 23,688 $ 19,100 $ 4,588 $ 1,792 The following table presents the average recorded investment in impaired loans and the related interest recognized during the periods indicated: Three Months Ended March 31, 2016 Three Months Ended March 31, 2015 (Dollars in thousands) Average recorded investment Interest income recognized Average recorded investment Interest income recognized Commercial real estate $ 9,668 $ 43 $ 15,479 $ 45 Commercial and industrial 8,424 26 11,256 34 Commercial construction 2,975 37 2,624 26 Residential 308 — 459 — Home equity 246 (2 ) 179 1 Consumer 22 — 49 — Total $ 21,643 $ 104 $ 30,046 $ 106 At March 31, 2016 , additional funding commitments for impaired loans totaled $469 thousand . The Company's obligation to fulfill the additional funding commitments on impaired loans is generally contingent on the borrower's compliance with the terms of the credit agreement. If the borrower is not in compliance, additional funding commitments may or may not be made at the Company's discretion. Troubled debt restructurings Loans are designated as a TDR when, as part of an agreement to modify the original contractual terms of the loan as a result of financial difficulties of the borrower, the Bank grants the borrower a concession on the terms, that would not otherwise be considered. Typically, such concessions may consist of a reduction in interest rate to a below market rate, taking into account the credit quality of the note, or a deferment or reduction of payments (principal or interest) which materially alters the Bank's position or significantly extends the note's maturity date, such that the present value of cash flows to be received is materially less than those contractually established at the loan's origination. All loans that are modified are reviewed by the Company to identify if a TDR has occurred. TDR loans are included in the impaired loan category and, as such, these loans are individually evaluated and a specific reserve is assigned for the amount of the estimated probable credit loss. Total TDR loans, included in the impaired loan balances above, as of March 31, 2016 and December 31, 2015 , were $15.6 million and $17.1 million , respectively. TDR loans on accrual status amounted to $10.3 million and $10.1 million at March 31, 2016 and December 31, 2015 , respectively. TDR loans included in non-performing loans amounted to $5.3 million and $7.1 million at March 31, 2016 and December 31, 2015 , respectively. The Company continues to work with commercial relationships and enters into loan modifications to the extent deemed to be necessary or appropriate while attempting to achieve the best mutual outcome given the current economic environment. At March 31, 2016 , additional funding commitments for TDR loans totaled $469 thousand . The Company's obligation to fulfill the additional funding commitments on TDR loans is generally contingent on the borrower's compliance with the terms of the credit agreement. If the borrower is not in compliance, additional funding commitments may or may not be made at the Company's discretion. The following tables present certain information regarding loan modifications classified as troubled debt restructures. Loans modified as troubled debt restructurings during the three months ended March 31, 2016 are detailed below. Three months ended March 31, 2016 (Dollars in thousands) Number of restructurings Pre-modification outstanding recorded investment Post-modification outstanding recorded investment Commercial real estate — $ — $ — Commercial and industrial 1 264 264 Commercial construction — — — Residential — — — Home equity — — — Consumer — — — Total 1 $ 264 $ 264 There were no loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the three months ended March 31, 2016 . There were no subsequent charge-offs associated with the TDRs noted in the table above during the three months ended months ended March 31, 2016 . At March 31, 2016 , there were no specific reserves allocated to the TDRs entered into during the 2016 period as management considered it likely that the unreserved principal will ultimately be collected. The TDR noted in the table above was on accrual status pre and post modification. Loans modified as troubled debt restructurings during the three month period ended March 31, 2015 are detailed below. Three months ended March 31, 2015 (Dollars in thousands) Number of restructurings Pre-modification outstanding recorded investment Post-modification outstanding recorded investment Commercial real estate — $ — $ — Commercial and industrial 4 869 869 Commercial construction — — — Residential — — — Home equity — — — Consumer — — — Total 4 $ 869 $ 869 There were no loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the period. At March 31, 2015 , there were specific reserves of $61 thousand allocated to the TDRs entered into during the 2015 period as management considered it likely that the unreserved principal would ultimately be collected. Interest payments received on non-accruing TDRs in the table above which were applied to principal and not recognized in interest income during the three months ended months ended amounted to $1 thousand . There were no subsequent charge-offs associated with the TDRs noted in the table above during the three months ended March 31, 2015 . Other real estate owned ( " OREO " ) Real estate acquired by the Company through foreclosure proceedings or the acceptance of a deed in lieu of foreclosure is classified as OREO. When property is acquired, it is generally recorded at the lesser of the loan's remaining principal balance, net of any unamortized deferred fees, or the estimated fair value of the property acquired, less estimated costs to sell, establishing a new cost basis. The estimated fair value is based on market appraisals and the Company's internal analysis. Any loan balance in excess of the estimated realizable fair value on the date of transfer is charged to the allowance for loan losses on that date. All costs incurred thereafter in maintaining the property, as well as subsequent declines in fair value, are charged to non-interest expense. The Company carried no OREO at both March 31, 2016 and December 31, 2015 . There were no sales on OREO during the three months ended March 31, 2016 ; there were also no additions to OREO, or subsequent impairment write-downs during the period. During the three months ended March 31, 2015 , the Company recorded $154 thousand of net gains on OREO sales; however there were no subsequent write downs of OREO during that period. Allowance for loan loss activity The allowance for loan losses is established through a provision for loan losses, a direct charge to earnings. Loan losses are charged against the allowance when management believes that the collectability of the loan principal is unlikely. Recoveries on loans previously charged-off are credited to the allowance. The allowance for loan losses amounted to $29.9 million at March 31, 2016 , compared to $29.0 million at December 31, 2015 , and $27.8 million at March 31, 2015 . For the three months ended March 31, 2016 and March 31, 2015 , the provision for loan losses amounted to $850 thousand and $625 thousand , respectively. The increase in the provision for the three months ended March 31, 2016 was due primarily to additional reserves allocated to criticized and adversely classified commercial loans. In determining the provision to the allowance for loan losses, management takes into consideration the level of loan growth and an estimate of credit risk, which includes such items as adversely classified and non-performing loans, the estimated specific reserves needed for impaired loans, the level of net charge-offs, and the estimated impact of current economic conditions on credit quality. Loan growth for the three months ended March 31, 2016 was $4.7 million compared to $9.5 million during the three months ended March 31, 2015 . Total non-performing loans as a percentage of total loans declined to 0.60% at March 31, 2016 , compared to 1.07% at March 31, 2015 . The balance of the allowance for loan losses allocated to impaired loans amounted to $2.1 million at March 31, 2016 , compared to $2.7 million at March 31, 2015 . The balance of the allowance for loan losses allocated to non-impaired classified loans amounted to $2.2 million at March 31, 2016 , compared to $1.6 million at March 31, 2015 . The Company recorded net recoveries of $52 thousand for the three months ended March 31, 2016 , compared to net recoveries of $57 thousand for the three months ended March 31, 2015 . The allowance for loan losses to total loans ratio was 1.60% at March 31, 2016 , 1.56% at December 31, 2015 and 1.65% at March 31, 2015 . The decline in the allowance ratio reflects the generally improving credit quality of the loan portfolio due, in part, to improved economic conditions. However, in the current period, the credit ratings of three larger commercial relationships were downgraded to "criticized" or "adverse" risk-ratings, based on a review of their individual business circumstances, requiring higher levels of reserves in the current period which increased the allowance to total loan ratio compared to December 31, 2015 . Management continues to closely monitor the non-performing assets, charge-offs and necessary allowance levels, including specific reserves. Based on management's judgment as to the existing credit risks inherent in the loan portfolio, as discussed above under the heading "Credit Quality Indicators," management believes that the Company's allowance for loan losses is adequate to absorb probable losses from specifically known and other credit risks associated with the portfolio as of March 31, 2016 . Changes in the allowance for loan losses by segment for the three months ended months ended March 31, 2016 are presented below: (Dollars in thousands) Cmml Real Estate Cmml and Industrial Cmml Constr Resid. Mortgage Home Equity Consumer Total Beginning Balance at December 31, 2015 $ 13,514 $ 9,758 $ 3,905 $ 1,061 $ 540 $ 230 $ 29,008 Provision 294 463 64 16 6 7 850 Recoveries 19 129 — — — 2 150 Less: Charge offs — 72 5 — 5 16 98 Ending Balance at March 31, 2016 $ 13,827 $ 10,278 $ 3,964 $ 1,077 $ 541 $ 223 $ 29,910 Ending allowance balance: Allotted to loans individually evaluated for impairment $ 179 $ 1,420 $ 488 $ — $ — $ 21 $ 2,108 Allotted to loans collectively evaluated for impairment $ 13,648 $ 8,858 $ 3,476 $ 1,077 $ 541 $ 202 $ 27,802 Changes in the allowance for loan losses by segment for the three months ended months ended March 31, 2015 are presented below: (Dollars in thousands) Cmml Real Estate Cmml and Industrial Cmml Constr Resid. Mortgage Home Equity Consumer Total Beginning Balance at December 31, 2014 $ 12,664 $ 9,245 $ 3,384 $ 989 $ 608 $ 231 $ 27,121 Provision 78 530 11 (29 ) 7 28 625 Recoveries 5 84 13 — — 8 110 Less: Charge offs — 17 — — — 36 53 Ending Balance at March 31, 2015 $ 12,747 $ 9,842 $ 3,408 $ 960 $ 615 $ 231 $ 27,803 Ending allowance balance: Allotted to loans individually evaluated for impairment $ 165 $ 1,951 $ 528 $ — $ 22 $ 49 $ 2,715 Allotted to loans collectively evaluated for impairment $ 12,582 $ 7,891 $ 2,880 $ 960 $ 593 $ 182 $ 25,088

Deposits

Deposits	3 Months Ended
	Mar. 31, 2016
Deposits [Abstract]
Deposits	Deposits are summarized as follows: (Dollars in thousands) March 31, 2016 December 31, 2015 Non-interest bearing demand deposits $ 599,282 $ 570,589 Interest bearing checking 313,314 313,674 Savings 179,127 167,304 Money market 735,492 692,114 Certificates of deposit $250,000 or less 127,925 129,993 Certificates of deposit more than $250,000 43,309 37,704 Total non-brokered deposits (1) 1,998,449 1,911,378 Brokered deposits (2) 89,288 106,770 Total deposits $ 2,087,737 $ 2,018,148 (1) Includes reciprocal money market deposits and CDs received from participating banks in nationwide networks as a result of our customers electing to participate in programs to obtain full FDIC insurance. Essentially, the equivalent of the original deposit comes back to the Company as non-brokered deposits within the appropriate category under total deposits on the balance sheet. (2) Primarily brokered CDs $250,000 and under.

Borrowed Funds and Subordinated

Borrowed Funds and Subordinated Debt	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Borrowed Funds and Subordinated Debt	Borrowed Funds and Subordinated Debt Borrowed funds amounted to $671 thousand at March 31, 2016 , compared to $53.7 million at December 31, 2015 . At March 31, 2016 borrowed funds consisted of FHLB borrowings only. At December 31, 2015 the borrowed funds balance was comprised of FHLB borrowings of $40.7 million and Other borrowings, which represented an overnight borrowing with a correspondent bank, totaling $13.0 million . The Company also carried subordinated debt of $14.8 million at both March 31, 2016 and December 31, 2015 . The subordinated debt carried at both March 31, 2016 and December 31, 2015 consisted of $15.0 million in aggregate principal amount of Fixed-to-Floating Rate Subordinated Notes (the "Notes"), issued in January 2015 , in a private placement to an accredited investor. The Notes, which are intended to qualify as Tier 2 capital for regulatory purposes, mature on January 30, 2030 (the "Maturity Date") and are callable by the Company, subject to regulatory approval, at a premium beginning January 30, 2020 , and at par beginning January 30, 2025 . The Notes pay interest at a fixed rate of 6.00% per annum through January 30, 2025 , and beginning on January 31, 2025 through the Maturity Date, or any early redemption date, the interest rate on the Notes will adjust monthly at an interest rate of 3.90% plus 30-day LIBOR. Original note issuance costs were $190 thousand and have been netted against the subordinated debt on the balance sheet in accordance with recent accounting guidance which the Company adopted in the first quarter of 2015. These costs are being amortized over the life of the Notes. Prior to the end of March 2015 , the Company had subordinated debt consisting of Junior Subordinated Debt Securities (the "Debt"). In March 2000, Enterprise (MA) Capital Trust I (the "Trust"), a subsidiary of Enterprise Bancorp, issued $10.5 million of 10.88% trust preferred securities that were to mature in 2030 and were callable at a premium. The proceeds from the sale of the trust preferred securities were used by the Trust, along with the Company's $325 thousand capital contribution, to acquire $10.8 million in aggregate principal amount of the Company's 10.88% Debt that was to mature in 2030 and was callable. In March 2015 , the Company redeemed the Debt in full using proceeds from the $15.0 million in Notes issued in January 2015 , which in turn allowed the Trust to redeem in full the trust preferred securities.

Derivatives and Hedging Activit

Derivatives and Hedging Activities	3 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives and Hedging Activities	Derivatives and Hedging Activities Interest rate lock commitments related to the origination of mortgage loans that will be sold are considered derivative instruments. The commitments to sell loans are also considered derivative instruments. The Company generally does not pool mortgage loans for sale, but instead, sells the loans on an individual basis. To reduce the net interest rate exposure arising from its loan sale activity, the Company enters into the commitment to sell these loans at essentially the same time that the interest rate lock commitment is quoted on the origination of the loan. The Company estimates the fair value of these derivatives based on current secondary mortgage market prices. At March 31, 2016 and 2015 , the estimated fair values of these derivative instruments were considered to be immaterial. The Company may use interest-rate swap agreements as part of its interest-rate risk management strategy. Interest-rate swap agreements are entered into as hedges against future interest-rate fluctuations on specifically identified assets or liabilities. The Company did not have derivative fair value hedges or derivative cash flow hedges at March 31, 2016 and 2015 . Beginning in the fourth quarter of 2015, the Company implemented a “Back-to-Back Swap” program whereby the Bank enters into an interest rate swap with a qualified commercial banking customer and simultaneously enters into an equal and opposite interest rate swap with a counterparty. The transaction structure effectively minimizes the Bank’s net risk exposure resulting from such transactions. The customer interest-rate swap agreement allows commercial banking customers to convert a floating-rate loan payment to fixed-rate loan payment. Back-to-Back Swaps are not speculative but rather, result from a service the Company provides to certain customers. Back-to-Back Swaps do not meet hedge accounting requirements and therefore changes in the fair value of both the customer swaps and the counterparty swaps, which have an offsetting inverse relationship, are recognized directly in earnings. The Company had two interest-rate swaps at both March 31, 2016 and December 31, 2015 with an aggregate notional amount of $10.1 million at the end of both periods. Asset derivatives and liability derivatives are included in prepaid expenses and other assets and accrued expenses and other liabilities on the consolidated balance sheets, respectively. The table below presents the fair value and classification of the Company’s derivative financial instruments for the periods presented: As of March 31, 2016 As of December 31, 2015 (Dollars in thousands) Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives Back-to-Back Swaps $ 225 $ 225 $ 16 $ 16 There was no gain or loss recognized in income on derivatives during the three months ended March 31, 2016 . By using derivative financial instruments, the Company exposes itself to credit risk. Credit risk is the risk of failure by 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 Company, which creates credit risk for the Company. When the fair value of a derivative is negative, the Company owes the counterparty and, therefore, it does not possess credit risk. The credit risk in derivative instruments is mitigated by entering into transactions with highly-rated counterparties that management believes to be creditworthy. As the swaps are subject to master netting agreements, the Company had limited exposure relating to interest rate swaps with institutional counterparties at March 31, 2016 . The Company did not have any credit risk exposure for derivative financial instruments at March 31, 2016 . Certain derivative agreements contain provisions that require the Company to post collateral if the derivative exposure exceeds a threshold amount. See the table below for amounts held at each period presented. The table below also presents the offsetting of derivatives and amounts subject to master netting agreements not offset in the consolidated balance sheet at the dates indicated. March 31, 2016 Gross Amounts of Recognized Asset/Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets Presented in the Statement of Financial Position Gross amounts not offset in the Statement of Financial Position (Dollars in thousands) Financial Instruments Cash collateral (Received)/Posted Net Amount Asset Derivatives Back-to-Back Swaps $ 225 — $ 225 — — $ 225 Liability Derivatives Back-to-Back Swaps $ 225 — $ 225 — 240 $ (15 ) December 31, 2015 Gross Amounts of Recognized Asset/Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets Presented in the Statement of Financial Position Gross amounts not offset in the Statement of Financial Position (Dollars in thousands) Financial Instruments Cash collateral (Received)/Posted Net Amount Asset Derivatives Back-to-Back Swaps $ 16 — $ 16 — — $ 16 Liability Derivatives Back-to-Back Swaps $ 16 — $ 16 — — $ 16 The Company has agreements with certain derivative counterparties that contain credit-risk-related contingent provisions. These provisions provide the counterparty with the right to terminate its derivative positions and require the Company to settle its obligations under the agreements if the Company defaults on certain of its indebtedness.

Supplemental Retirement Plan an

Supplemental Retirement Plan and Other Postretirement Benefit Obligations	3 Months Ended
	Mar. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Supplemental Retirement Plan and Other Postretirement Benefit Obligations	Supplemental Retirement Plan and Other Postretirement Benefit Obligations Supplemental Retirement Plan The Company has salary continuation agreements with two of its current executive officers and one former executive officer. These agreements provide for predetermined fixed-cash supplemental retirement benefits to be provided for a period of 20 years after each individual reaches a defined "benefit age." The individuals covered under the SERP have reached the defined benefit age and are receiving payments under the plan. Additionally, the Company has not recognized service costs in the current or prior year as each officer had previously attained their individually defined benefit age and was fully vested under the plan. This non-qualified plan represents a direct liability of the Company, and as such has no specific assets set aside to settle the benefit obligation. The funded status is the aggregate amount accrued, or the "accumulated benefit obligation," which is equal to the present value of the benefits to be provided to the employee or any beneficiary. Because the Company's benefit obligations provide for predetermined fixed-cash payments, the Company does not have any unrecognized costs to be included as a component of accumulated other comprehensive income. Total net periodic benefit costs, comprised of interest costs only, were $31 thousand for both the three months ended March 31, 2016 and March 31, 2015 . Benefits paid amounted to $69 thousand for both the three months ended March 31, 2016 and March 31, 2015 . The Company anticipates accruing an additional $93 thousand to the plan during the remainder of 2016 . Supplemental Life Insurance The Company has provided supplemental life insurance through split-dollar life insurance arrangements for certain executive and senior officers on whom the Bank owns bank-owned life insurance ("BOLI"). These arrangements provide a death benefit to the officer's designated beneficiaries that extend to postretirement periods for some of the supplemental life insurance plans. The Company has recognized a liability for these future postretirement benefits. These non-qualified plans represent a direct liability of the Company, and as such has no specific assets set aside to settle the benefit obligation. The funded status is the aggregate amount accrued, or the "accumulated postretirement benefit obligation," which is the present value of the post-retirement benefits associated with this arrangement. The total net periodic benefit costs, which were comprised primarily of interest costs, amounted to $19 thousand for the three months ended March 31, 2016 , compared to $18 thousand for the three months ended March 31, 2015 .

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Company currently has three individual stock incentive plans: the 2003 plan as amended in 2009, the 2009 plan as amended in 2015 and the 2016 plan. The plans permit the Board of Directors to grant, under various terms, both incentive and non-qualified stock options (for the purchase of newly issued shares of common stock), restricted stock, restricted stock units and stock appreciation rights to officers and other employees, directors and consultants. These plans also allow for newly issued shares of common stock to be issued without restrictions, to officers and other employees, directors and consultants. As of March 31, 2016 , 107,992 shares remain available for future grants under the 2009 plan. The 2016 plan which was approved by our stockholders at the May 2016 annual meeting, with essentially the same terms as the 2003 and 2009 plans, has 350,000 shares available for future grants. The 2003 plan is closed to future grants, although several awards previously granted under this plan remain outstanding and may be exercised in the future. The Company's stock-based compensation expense includes stock options and stock awards to officers and other employees included in salary and benefits expense, and stock awards and stock compensation in lieu of cash fees to non-employee directors included in other operating expenses. Total stock-based compensation expense was $443 thousand for the three months ended March 31, 2016 , compared to $488 thousand for the three months ended March 31, 2015 . Stock Option Awards The Company recognized stock-based compensation expense related to stock option awards of $79 thousand for the three months ended March 31, 2016 , compared to $97 thousand for the three months ended March 31, 2015 . The Company utilizes the Black-Scholes option valuation model in order to determine the per share grant date fair value of option grants. The table below provides a summary of the options granted in 2016 and 2015 . Three Months Ended March 31, 2016 2015 Options granted 30,613 27,115 Term in years 10 10 Average assumptions used in the fair value model: Expected volatility 42 % 47 % Expected dividend yield 3.03 % 2.89 % Expected life in years 7 7 Risk-free interest rate 1.91 % 1.95 % Market price on date of grant $ 21.86 $ 21.03 Per share weighted average fair value $ 7.90 $ 8.51 Fair value as a percentage of market value at grant date 36 % 40 % Options granted during the first three months of 2016 and 2015 vest 50% in year two and 50% in year four, on the anniversary date of the awards. Vested options are only exercisable while the employee remains employed with the Bank and for a limited time thereafter. If a grantee’s employment or other service relationship, such as service as a director, is terminated for any reason, then any stock options granted that have not vested as of the time of such termination generally must be forfeited, unless the Compensation Committee or the Board of Directors, as the case may be, waives such forfeiture requirement. Refer to Note 11 "Stock-Based Compensation Plans" in the Company's 2015 Annual Report on Form 10-K for a further description of the assumptions used in the valuation model. Stock Awards Stock-based compensation expense recognized in association with stock awards amounted to $294 thousand for the three months ended March 31, 2016 , compared to $309 thousand for the three months ended March 31, 2015 . Restricted stock awards are granted at the market price on the date of the grant. Employee awards generally vest over four years in equal portions beginning on or about the first anniversary date of the award or are performance based awards that vest upon the Company achieving certain predefined performance objectives. Non-employee director awards generally vest over two years in equal portions beginning on or about the first anniversary date of the award. The table below provides a summary of restricted stock awards granted in 2016 and 2015 . Three Months Ended March 31, Restricted Stock Awards 2016 2015 Two Year Vesting 9,060 7,276 Four Year Vesting 17,453 17,181 Performance-Based Vesting 35,071 30,262 Total Restricted Stock Awards 61,584 54,719 Weighted average grant date fair value $ 21.86 $ 21.03 If a grantee's employment or other service relationship, such as service as a director, is terminated for any reason, then any shares of restricted stock granted that have not vested as of the time of such termination generally must be forfeited, unless the Compensation Committee or the Board of Directors, as the case may be, waives such forfeiture requirement. The restricted stock awards allow for the receipt of dividends, and the voting of all shares, whether or not vested, throughout the vesting periods at the same proportional level as common shares outstanding. Upon vesting, restricted stock awards may be net share-settled to cover payment for employee tax obligations, resulting in shares of common stock being reacquired by the Company. In accordance with Chapter 156D of the Massachusetts General Laws, a statute known as the Massachusetts Business Corporation Act, which applies to Massachusetts corporations such as the Company, eliminates the concept of “treasury stock” and provides that shares a Massachusetts company reacquires will be treated as authorized but unissued shares. Stock in Lieu of Directors' Fees In addition to restricted stock awards discussed above, the non-employee members of the Company's Board of Directors may opt to receive newly issued shares of the Company's common stock in lieu of cash compensation for attendance at Board and Board Committee meetings. Stock-based compensation expense related to these directors' fees amounted to $70 thousand for the three months ended March 31, 2016 , compared to $82 thousand for the three months ended March 31, 2015 , and is included in other operating expenses. In January 2016 , non-employee directors were issued 10,657 shares of common stock in lieu of 2015 annual cash fees of $254 thousand at a market value price of $23.86 per share, the market value of the common stock on the opt-in measurement date of January 2, 2015 .

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	Earnings per share Basic earnings per share are calculated by dividing net income available to common stockholders by the weighted average number of common shares outstanding (including participating securities) during the year. The Company's only participating securities are unvested restricted stock awards that contain non-forfeitable rights to dividends. Diluted earnings per share reflects the effect on weighted average shares outstanding of the number of additional shares outstanding if dilutive stock options were converted into common stock using the treasury stock method. The table below presents the increase in average shares outstanding, using the treasury stock method, for the diluted earnings per share calculation for the periods indicated: Three Months Ended March 31, 2016 2015 Basic weighted average common shares outstanding 10,405,112 10,243,044 Dilutive shares 66,672 67,430 Diluted weighted average common shares outstanding 10,471,784 10,310,474 For the three months ended March 31, 2016 , all options outstanding were included in the year-to-date calculation of diluted earnings per share, as they were all considered "in the money" under the treasury stock method.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The FASB defines the fair value of an asset or liability to be the price which a seller would receive in an orderly transaction between market participants (an exit price) and also establishes a fair value hierarchy segregating fair value measurements using three levels of inputs: (Level 1) quoted market prices in active markets for identical assets or liabilities; (Level 2) significant other observable inputs, including quoted prices for similar items in active markets, quoted prices for identical or similar items in markets that are not active, inputs such as interest rates and yield curves, volatilities, prepayment speeds, credit risks and default rates which provide a reasonable basis for fair value determination or inputs derived principally from observed market data; and (Level 3) significant unobservable inputs for situations in which there is little, if any, market activity for the asset or liability. Unobservable inputs must reflect reasonable assumptions that market participants would use in pricing the asset or liability, which are developed on the basis of the best information available under the circumstances. The following tables summarize significant assets and liabilities carried at fair value and placement in the fair value hierarchy at the dates specified: March 31, 2016 Fair Value Measurements using: (Dollars in thousands) Fair Value (level 1) (level 2) (level 3) Assets measured on a recurring basis: Fixed income securities $ 292,500 $ — $ 292,500 $ — Equity securities 12,446 12,446 — — FHLB stock 2,793 — — 2,793 Interest-rate swaps 225 — 225 — Assets measured on a non-recurring basis: Impaired loans (collateral dependent) 3,088 — — 3,088 Liabilities measured on a recurring basis Interest-rate swaps 225 — 225 — December 31, Fair Value Measurements using: (Dollars in thousands) Fair Value (level 1) (level 2) (level 3) Assets measured on a recurring basis: Fixed income securities $ 288,701 $ — $ 288,701 $ — Equity securities 11,657 11,657 — — FHLB stock 3,050 — — 3,050 Interest-rate swaps 16 — 16 — Assets measured on a non-recurring basis: Impaired loans (collateral dependent) 2,516 — — 2,516 Liabilities measured on a recurring basis Interest-rate swaps 16 — 16 — The Company did not have cause to transfer any assets between the fair value measurement levels during the three months ended March 31, 2016 or the year ended December 31, 2015 . All of the Company's fixed income investments and equity securities that are considered "available-for-sale" are carried at fair value. The fixed income category above includes federal agency obligations, commercial and residential federal agency MBS, municipal securities, corporate bonds and certificates of deposits, as held at those dates. The Company utilizes third-party pricing vendors to provide valuations on its fixed income securities. Fair values provided by the vendors were generally determined based upon pricing matrices utilizing observable market data inputs for similar or benchmark securities in active markets and/or based on a matrix pricing methodology which employs The Bond Market Association's standard calculations for cash flow and price/yield analysis, live benchmark bond pricing and terms/condition data available from major pricing sources. Therefore, management regards the inputs and methods used by third-party pricing vendors to be "Level 2 inputs and methods" as defined in the "fair value hierarchy." The Company periodically obtains a second price from an impartial third party on fixed income securities to assess the reasonableness of prices provided by the primary independent pricing vendor. The Company's equity portfolio fair value is measured based on quoted market prices for the shares; therefore, these securities are categorized as Level 1 within the fair value hierarchy. The Bank is required to purchase FHLB stock at par value in association with advances from the FHLB; this stock is classified as a restricted investment and carried at cost which management believes approximates fair value; therefore, these securities are categorized as Level 3 measures. See Note 1, "Summary of Significant Accounting Policies," Item (d) for further information regarding the Company's fair value assessment of FHLB capital stock. Impaired loan balances in the table above represent those collateral dependent impaired commercial loans where management has estimated the credit loss by comparing the loan's carrying value against the expected realizable fair value of the collateral (appraised value, or internal analysis less estimated cost to sell, adjusted as necessary for changes in relevant valuation factors subsequent to the measurement date). Certain inputs used in these assessments, and possible subsequent adjustments, are not always observable, and therefore, collateral dependent impaired loans are categorized as Level 3 within the fair value hierarchy. A specific allowance is assigned to the collateral dependent impaired loan for the amount of management's estimated probable credit loss. The specific allowances assigned to the collateral dependent impaired loans at March 31, 2016 amounted to $1.2 million compared to $1.4 million at December 31, 2015 . When OREO property is acquired, it is generally recorded at the lesser of the loan's remaining principal balance, net of unamortized deferred fees, or the estimated fair value of the property acquired, less estimated costs to sell. The estimated fair value is based on market appraisals and the Company's internal analysis. Certain inputs used in appraisals or the Company's internal analysis are not always observable and therefore, OREO may be categorized as Level 3 within the fair value hierarchy. The Company carried no OREO at both March 31, 2016 and December 31, 2015 . There were no sales on OREO during the three months ended March 31, 2016 ; there were also no additions to OREO, or subsequent impairment write-downs during the period. During the three months ended March 31, 2015 , the Company recorded $154 thousand of net gains on OREO sales; however there were no subsequent write downs of OREO during that period. The fair values for the interest-rate swap assets and liabilities represent a FASB Level 2 measurement and are based on settlement values adjusted for credit risks associated with the counterparties and the Company and observable market interest rate curves. The settlement values are based on discounted cash flow analysis, a widely accepted valuation technique, reflecting the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. Credit risk adjustments consider factors such as the likelihood of default by the Company and its counterparties, its net exposures and remaining contractual life. The change in value of interest-rate swap assets and liabilities attributable to credit risk was not significant during the reported periods. Refer also to Note 7, "Derivatives and Hedging Activities," for additional information on the Company's interest-rate swaps. Standby letters of credit are conditional commitments issued by the Company to guarantee the financial obligation or performance of a customer to a third party. The fair value of these commitments was estimated to be the fees charged to enter into similar agreements, and accordingly these fair value measures are deemed to be FASB Level 2 measurements. In accordance with the FASB, the estimated fair values of these commitments are carried on the balance sheet as a liability and amortized to income over the life of the letters of credit, which are typically one year. The estimated fair value of these commitments carried on the balance sheet at March 31, 2016 and December 31, 2015 were deemed immaterial. Interest rate lock commitments related to the origination of mortgage loans that will be sold are considered derivative instruments. The commitments to sell loans are also considered derivative instruments. The Company generally does not pool mortgage loans for sale, but instead sells the loans on an individual basis. To reduce the net interest rate exposure arising from its loan sale activity, the Company enters into the commitment to sell these loans at essentially the same time that the interest rate lock commitment is quoted on the origination of the loan. The Company estimates the fair value of these derivatives based on current secondary mortgage market prices. These commitments are accounted for in accordance with FASB guidance. The fair values of the Company's derivative instruments are deemed to be FASB Level 2 measurements. At March 31, 2016 and December 31, 2015 , the estimated fair value of the Company's derivative instruments was considered to be immaterial. The following table presents additional quantitative information about assets measured at fair value on a recurring and non-recurring basis for which the Company utilized Level 3 inputs (significant unobservable inputs for situations in which there is little, if any, market activity for the asset or liability) to determine fair value as of March 31, 2016 (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Unobservable Input Value or Range Assets measured on a recurring basis: FHLB stock $2,793 FHLB Stated Par Value N/A N/A Assets measured on a non-recurring basis: Impaired loans (collateral dependent) $3,088 Appraisal of collateral Appraisal adjustments (1) 5% - 50% (1) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses. Estimated Fair Values of Assets and Liabilities In addition to disclosures regarding the measurement of assets and liabilities carried at fair value on the balance sheet, the Company is also required to disclose fair value information about financial instruments for which it is practicable to estimate that value, whether or not recognized on the balance sheet. The carrying values, estimated fair values and placement in the fair value hierarchy of the Company's financial instruments for which fair value is only disclosed but not recognized on the balance sheet at the dates indicated are summarized as follows: March 31, 2016 Fair value measurement (Dollars in thousands) Carrying Amount Fair Value Level 1 inputs Level 2 Inputs Level 3 Inputs Financial assets: Loans held for sale $ 770 $ 771 $ — $ 771 $ — Loans, net 1,834,782 1,850,258 — — 1,850,258 Financial liabilities: Certificates of deposit (including brokered) 260,522 260,636 — 260,636 — Borrowed funds 671 671 — 671 — Subordinated debt 14,825 14,758 — — 14,758 December 31, 2015 Fair value measurement (Dollars in thousands) Carrying Amount Fair Value Level 1 inputs Level 2 Inputs Level 3 Inputs Financial assets: Loans held for sale $ 1,709 $ 1,709 $ — $ 1,709 $ — Loans, net 1,830,954 1,845,009 — — 1,845,009 Financial liabilities: Certificates of deposit (including brokered) 274,467 273,419 — 273,419 — Borrowed funds 53,671 53,670 — 53,670 — Subordinated debt 14,822 13,961 — — 13,961 Excluded from the tables above are certain financial instruments with carrying values that approximated their fair value at the dates indicated, as they were short-term in nature or payable on demand. These include cash and cash equivalents, accrued interest receivable, non-term deposit accounts, and accrued interest payable. The respective carrying values of these instruments would all be considered to be classified within Level 1 of their fair value hierarchy. Also excluded from these tables are the fair values of commitments for unused portion of lines of credit and letters of credit, which were estimated to be the fees currently charged to enter into similar agreements and are deemed to be immaterial, as well as commitments to originate non-mortgage loans which were short-term, at current market rates and estimated to have no significant change in fair value. When determining fair values noted in the tables above, in cases where quoted fair values are not available, fair values are based upon estimates using various valuation techniques. Those techniques are significantly affected by the assumptions used, including the discount rate and estimates of future cash flows. The following methods and assumptions were used by the Company in estimating fair values of its financial instruments: Loans held for sale: Loans held for sale are recorded at the lower of aggregate amortized cost or market value. The fair value is based on comparable market prices for loans with similar rates and terms. Loans: The fair value of loans was determined using discounted cash flow analysis, using interest rates currently being offered by the Company. The incremental credit risk for adversely classified loans was considered in the determination of the fair value of the loans. This method of estimating fair value does not incorporate the exit price concept of fair value. Financial liabilities: The fair values of certificates of deposit and borrowings were estimated using discounted cash flow analysis using rates offered by the Bank or advance rates offered by the FHLB on March 31, 2016 and December 31, 2015 for similar instruments. The fair value of subordinated debt was estimated using discounted cash flow analysis using a market rate of interest at March 31, 2016 and December 31, 2015 . Limitations: The estimates of fair value of financial instruments were based on information available at March 31, 2016 and December 31, 2015 and are not indicative of the fair market value of those instruments as of the date of this Quarterly Report on Form 10-Q. These estimates do not reflect any premium or discount that could result from offering for sale at one time the Company's entire holdings of a particular financial instrument. The fair value of the Company's time deposit liabilities do not take into consideration the value of the Company's long-term relationships with depositors, which may have significant value. Because no active market exists for a portion of the Company's financial instruments, fair value estimates were based on judgments regarding future expected loss experience, current economic conditions, risk characteristics of various financial instruments, and other factors. These estimates are subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. Changes in assumptions could significantly affect the estimates. Fair value estimates were based on existing on- and off-balance sheet financial instruments without an attempt to estimate the value of anticipated future business and the value of assets and liabilities that are not considered financial instruments, including premises and equipment and foreclosed real estate. In addition, the tax ramifications related to the realization of the unrealized appreciation and depreciation can have a significant effect on fair value estimates and have not been considered in any of the estimates. Accordingly, the aggregate fair value amounts presented do not represent the underlying value of the Company.

Summary of Significant Accoun20

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Principles of Consolidation	The accompanying unaudited consolidated interim financial statements and these notes should be read in conjunction with the December 31, 2015 audited consolidated financial statements and notes thereto contained in the 2015 Annual Report on Form 10-K of Enterprise Bancorp, Inc. (the "Company" or "Enterprise"), a Massachusetts corporation, as filed with the Securities and Exchange Commission (the "SEC") on March 15, 2016 . The Company has not changed its accounting policies from those disclosed in its 2015 Annual Report on Form 10-K. The Company's unaudited consolidated interim financial statements include the accounts of the Company and its wholly owned subsidiary, Enterprise Bank and Trust Company (the "Bank"). The Bank is a Massachusetts trust company organized in 1989. Substantially all of the Company's operations are conducted through the Bank and its subsidiaries. The Bank's subsidiaries include Enterprise Insurance Services, LLC and Enterprise Investment Services, LLC, organized under the laws of the State of Delaware for the purposes of engaging in insurance sales activities and offering non-deposit investment products and services, respectively. In addition, the Bank has the following subsidiaries that are incorporated in the Commonwealth of Massachusetts and classified as security corporations in accordance with applicable Massachusetts General Laws: Enterprise Security Corporation; Enterprise Security Corporation II; and Enterprise Security Corporation III. The security corporations, which hold various types of qualifying securities, are limited to conducting securities investment activities that the Bank itself would be allowed to conduct under applicable laws. The Company has 22 full service branches serving the greater Merrimack Valley and North Central regions of Massachusetts and Southern New Hampshire. The Company also plans to open its second Nashua, NH branch in the second quarter of 2016. Through the Bank and its subsidiaries, the Company offers a range of commercial and consumer loan products, and deposit and cash management services. The Company also offers investment advisory and wealth management, trust and insurance services. The services offered through the Bank and its subsidiaries are managed as one strategic unit and represent the Company's only reportable operating segment. Prior to the end of March 2015, pursuant to the Accounting Standards Codification ("ASC") Topic 810 "Consolidation of Variable Interest Entities," issued by the Financial Accounting Standards Board ("FASB"), the Company carried Junior Subordinated Debentures as a liability on its consolidated financial statements, along with the related interest expense. The debentures were issued by a statutory business trust (the "Trust") created by the Company in March 2000 under the laws of the State of Delaware, and the trust preferred securities issued by the Trust, and the related non-interest expense, were excluded from the Company's consolidated financial statements. In March 2015 , the Company redeemed in full the Junior Subordinated Debentures, which in turn allowed the Trust to redeem in full the trust preferred securities. The Company also dissolved the Trust in April 2015. See Note 6, "Borrowed Funds and Subordinated Debt," below for further information on the Company's subordinated debt. The Federal Deposit Insurance Corporation (the "FDIC") and the Massachusetts Division of Banks (the "Division") have regulatory authority over the Bank. The Bank is also subject to certain regulatory requirements of the Board of Governors of the Federal Reserve System (the "Federal Reserve Board") and, with respect to its New Hampshire branch operations, the New Hampshire Banking Department. The business and operations of the Company are subject to the regulatory oversight of the Federal Reserve Board. The Division also retains supervisory jurisdiction over the Company.
Basis of Accounting	The accompanying unaudited consolidated interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") for interim financial information and the instructions for Form 10-Q through the rules and interpretive releases of the SEC under federal securities law. In the opinion of management, the accompanying unaudited consolidated interim financial statements reflect all necessary adjustments consisting of normal recurring accruals for a fair presentation. All significant intercompany balances and transactions have been eliminated in the accompanying unaudited consolidated interim financial statements. Interim results are not necessarily indicative of results to be expected for the entire year.
Reclassifications	Certain previous years' amounts in the consolidated financial statements, and notes thereto, have been reclassified to conform to the current year's presentation.
Critical Accounting Estimates	Critical Accounting Estimates In preparing the unaudited consolidated interim financial statements in conformity with GAAP, management is required to exercise judgment in determining many of the methodologies, assumptions and estimates to be utilized. These assumptions and estimates affect the reported values of assets and liabilities as of the balance sheet date and income and expenses for the period then ended. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates should the assumptions and estimates used change over time due to changes in circumstances. Changes in those estimates resulting from continuing change in the economic environment and other factors will be reflected in the financial statements and results of operations in future periods. As discussed in the Company's 2015 Annual Report on Form 10-K, the three most significant areas in which management applies critical assumptions and estimates that are particularly susceptible to change relate to the determination of the allowance for loan losses, impairment review of investment securities and the impairment review of goodwill. Refer to Note 1,"Summary of Significant Accounting Policies," to the Company's consolidated financial statements included in the Company's 2015 Annual Report on Form 10-K for significant accounting policies. The Company has not changed its significant accounting policies from those disclosed in its 2015 Annual Report filed on Form 10-K.
Reporting Comprehensive Income	Reporting Comprehensive Income Comprehensive income is defined as all changes to stockholders' equity except investments by and distributions to stockholders. Net income is one component of comprehensive income, with other components referred to in the aggregate as other comprehensive income. The Company's only other comprehensive income component is the net unrealized holding gains or losses on investments available-for-sale, net of deferred income taxes. Pursuant to Accounting Standards Update ("ASU") No. 2013-02, Comprehensive Income (Topic 220): Reporting Amounts Reclassified Out of Accumulated Other Comprehensive Income, the Company initially excludes these unrealized holding gains and losses from net income; however, they are later reported as reclassifications out of accumulated other comprehensive income into net income when the securities are sold. When securities are sold, the reclassification of realized gains and losses on available-for-sale securities are included on the Consolidated Statements of Income under the "non-interest income" subheading on the line item "net gains on sales of investment securities" and the related income tax expense is included in the line item "provision for income taxes," both of which are also detailed on the Consolidated Statements of Comprehensive Income under the subheading "reclassification adjustment for net gains included in net income."
Restricted Investments	Restricted Investments As a member of the Federal Home Loan Bank of Boston ("FHLB"), the Company is required to purchase certain levels of FHLB capital stock at par value in association with the Company's borrowing relationship from the FHLB. This stock is classified as a restricted investment and carried at cost, which management believes approximates fair value. FHLB stock represents the only restricted investment held by the Company. In conjunction with the other-than-temporary-impairment ("OTTI") review on available-for-sale investments (See Note 2, "Investments," for additional information), management also regularly reviews its holdings of FHLB stock for OTTI. Based on management's periodic review, the Company has not recorded any OTTI charges on this investment to date. If it was determined that a write-down of FHLB stock was required, impairment would be recognized through a charge to earnings.
Income Taxes	Income Taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are recognized for the future tax attributable to differences between the financial statement carrying amounts and the tax basis of assets and liabilities. The deferred tax assets and liabilities are reflected at currently enacted income tax rates applicable to the period in which the deferred tax assets or liabilities are expected to be realized or settled. As changes in tax laws or rates are enacted, deferred tax assets and liabilities will be adjusted accordingly through the provision for income taxes. The Company's policy is to classify interest resulting from underpayment of income taxes as income tax expense in the first period the interest would begin accruing according to the provisions of the relevant tax law. The Company classifies penalties resulting from underpayment of income taxes as income tax expense in the period for which the Company claims or expects to claim an uncertain tax position or in the period in which the Company's judgment changes regarding an uncertain tax position. The income tax provisions will differ from the expense that would result from applying the federal statutory rate to income before taxes, due primarily to the impact of tax exempt interest from certain investment securities, loans and bank-owned life insurance. The Company did not have any unrecognized tax benefits accrued as income tax liabilities or receivables or as deferred tax items at March 31, 2016 . The Company is subject to U.S. federal and state income tax examinations by taxing authorities for the 2012 through 2015 tax years.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board ("FASB") issued ASU No. 2015-03, Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in this ASU require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this ASU. Entities are required to apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. For public business entities, the amendments are effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption of the amendments is permitted for financial statements that have not been previously issued. The Company early adopted this ASU as of January 1, 2015 in relation to the Company's Fixed-to-Floating Rate Subordinated Notes issued in January 2015. This adoption did not have a material impact on the Company's financial statements or results of operations. In January 2015, the FASB issued Accounting Standards Update (ASU) 2015-01, "Income Statement-Extraordinary and Unusual Items (Subtopic 225-20): Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items." This ASU will align more closely GAAP income statement presentation guidance with International Audit Standards (IAS) 1, Presentation of Financial Statements, which prohibits the presentation and disclosure of extraordinary items. The amendments in this update are effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. The adoption of this standard did not have an impact on the Company's financial statements. For information regarding recent accounting pronouncements not yet adopted by the Company, see Item 2, "Management's Discussion and Analysis of Financial Condition and Results of Operations," under the heading "Recent Accounting Pronouncements Not Yet Adopted."

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Schedule of Available-for-sale Securities Reconciliation	The amortized cost and carrying values of investment securities at the dates specified are summarized as follows: March 31, 2016 (Dollars in thousands) Amortized cost Unrealized gains Unrealized losses Fair Value Federal agency obligations (1) $ 78,640 $ 1,097 $ 19 $ 79,718 Residential federal agency MBS (1) 72,069 844 184 72,729 Commercial federal agency MBS (1) 27,499 286 — 27,785 Municipal securities 97,040 2,928 43 99,925 Corporate bonds 10,284 128 29 10,383 Certificates of deposits (2) 1,943 17 — 1,960 Total fixed income securities 287,475 5,300 275 292,500 Equity investments 10,969 1,879 402 12,446 Total available-for-sale securities, at fair value $ 298,444 $ 7,179 $ 677 $ 304,946 December 31, 2015 (Dollars in thousands) Amortized cost Unrealized gains Unrealized losses Fair Value Federal agency obligations (1) $ 78,626 $ 352 $ 153 $ 78,825 Residential federal agency MBS (1) 75,105 406 648 74,863 Commercial federal agency MBS (1) 23,908 — 363 23,545 Municipal securities 96,189 2,357 35 98,511 Corporate bonds 10,257 44 95 10,206 Certificates of deposits (2) 2,753 — 2 2,751 Total fixed income securities 286,838 3,159 1,296 288,701 Equity investments 10,043 1,966 352 11,657 Total available-for-sale securities, at fair value $ 296,881 $ 5,125 $ 1,648 $ 300,358 __________________________________________ (1) These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae ("FNMA"), Freddie Mac ("FHLMC"), Federal Farm Credit Bank ("FFCB"), or one of several Federal Home Loan Banks, as well as, investments guaranteed by Ginnie Mae ("GNMA"), a wholly-owned government entity. (2) Certificates of deposits ("CDs") represent term deposits issued by banks that are subject to FDIC insurance and purchased on the open market.
Investments Classified by Contractual Maturity Date	The contractual maturity distribution at March 31, 2016 of total fixed income investments was as follows: Within One Year After One, But Within Five Years After Five, But Within Ten Years After Ten Years Amortized Cost Yields Amortized Cost Yields Amortized Cost Yields Amortized Cost Yields At amortized cost: Federal agency obligations $ 7,035 0.91 % $ 62,054 1.59 % $ 9,551 2.22 % $ — — % Residential federal agency MBS — — % 3,101 3.17 % 1,242 1.91 % 67,726 2.13 % Commercial federal agency MBS — — % — — % 27,499 2.26 % — — % Municipal securities 6,233 2.31 % 25,813 3.58 % 33,612 3.65 % 31,382 3.85 % Corporate bonds 528 1.33 % 5,175 2.15 % 4,581 2.94 % — — % CDs 993 0.34 % 950 2.13 % — — % — — % Total fixed income securities $ 14,789 1.48 % $ 97,093 2.21 % $ 76,485 2.90 % $ 99,108 2.67 % At fair value: Total fixed income securities $ 14,841 $ 98,726 $ 78,292 $ 100,641

Loans (Tables)

Loans (Tables)	3 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Schedule of Loans by Loan Classification	Major classifications of loans at the periods indicated were as follows: (Dollars in thousands) March 31, December 31, Commercial real estate $ 936,907 $ 936,921 Commercial and industrial 456,436 458,553 Commercial construction 207,214 202,993 Total commercial loans 1,600,557 1,598,467 Residential mortgages 170,585 169,188 Home equity loans and lines 84,665 83,373 Consumer 10,539 10,747 Total retail loans 265,789 263,308 Gross loans 1,866,346 1,861,775 Deferred loan origination fees, net (1,654 ) (1,813 ) Total loans 1,864,692 1,859,962 Allowance for loan losses (29,910 ) (29,008 ) Net loans $ 1,834,782 $ 1,830,954
Schedule of Loans Pledged as Collateral	Loans designated as qualified collateral and pledged to the FHLB for borrowing capacity are summarized below: (Dollars in thousands) March 31, December 31, Commercial real estate $ 277,056 $ 281,802 Residential mortgages 122,744 118,855 Home equity 13,349 13,972 Total loans pledged to FHLB $ 413,149 $ 414,629

Allowance For Loan Loss (Tables

Allowance For Loan Loss (Tables)	3 Months Ended
	Mar. 31, 2016
Receivables [Abstract]
Financing Receivables by Evaluation Method	The balances of loans as of March 31, 2016 by segment and evaluation method are summarized as follows: (Dollars in thousands) Loans individually evaluated for impairment Loans collectively evaluated for impairment Total Loans Commercial real estate $ 9,926 $ 926,981 $ 936,907 Commercial and industrial 7,853 448,583 456,436 Commercial construction 2,989 204,225 207,214 Residential 307 170,278 170,585 Home equity 309 84,356 84,665 Consumer 21 10,518 10,539 Deferred Fees — (1,654 ) (1,654 ) Total loans $ 21,405 $ 1,843,287 $ 1,864,692 The balances of loans as of December 31, 2015 by segment and evaluation method are summarized as follows: (Dollars in thousands) Loans individually evaluated for impairment Loans collectively evaluated for impairment Total Loans Commercial real estate $ 12,287 $ 924,634 $ 936,921 Commercial and industrial 7,810 450,743 458,553 Commercial construction 3,032 199,961 202,993 Residential 366 168,822 169,188 Home equity 169 83,204 83,373 Consumer 24 10,723 10,747 Deferred Fees — (1,813 ) (1,813 ) Total loans $ 23,688 $ 1,836,274 $ 1,859,962
Financing Receivable Credit Quality Indicators	The following tables present the Company's credit risk profile for each class of loan in its portfolio by internally assigned risk rating category at the periods indicated. March 31, 2016 Adversely Classified Not Adversely (Dollars in thousands) Substandard Doubtful Loss Classified Gross Loans Commercial real estate $ 11,586 $ — $ — $ 925,321 $ 936,907 Commercial and industrial 9,100 42 3 447,291 456,436 Commercial construction 1,734 — — 205,480 207,214 Residential 1,213 — — 169,372 170,585 Home equity 644 — — 84,021 84,665 Consumer 37 11 — 10,491 10,539 Total gross loans $ 24,314 $ 53 $ 3 $ 1,841,976 $ 1,866,346 December 31, 2015 Adversely Classified Not Adversely (Dollars in thousands) Substandard Doubtful Loss Classified Gross Loans Commercial real estate $ 12,487 $ — $ — $ 924,434 $ 936,921 Commercial and industrial 8,670 — 3 449,880 458,553 Commercial construction 1,776 — — 201,217 202,993 Residential 1,278 — — 167,910 169,188 Home equity 503 — 5 82,865 83,373 Consumer 38 11 — 10,698 10,747 Total gross loans $ 24,752 $ 11 $ 8 $ 1,837,004 $ 1,861,775
Past Due Financing Receivables	The following tables present age analysis of past due loans as of the dates indicated. Balance at March 31, 2016 (Dollars in thousands) Loans 30-59 Days Past Due Loans 60-89 Days Past Due Loans 90 or More Days Past Due (non- accrual) Total Past Due Loans Current Loans Gross Loans Commercial real estate $ 4,665 $ 398 $ 6,188 $ 11,251 $ 925,656 $ 936,907 Commercial and industrial 833 238 4,106 5,177 451,259 456,436 Commercial construction 175 — 213 388 206,826 207,214 Residential — 553 307 860 169,725 170,585 Home equity — — 424 424 84,241 84,665 Consumer 7 19 26 52 10,487 10,539 Total gross loans $ 5,680 $ 1,208 $ 11,264 $ 18,152 $ 1,848,194 $ 1,866,346 Balance at December 31, 2015 (Dollars in thousands) Loans 30-59 Days Past Due Loans 60-89 Days Past Due Loans 90 or More Days Past Due (non- accrual) Total Past Due Loans Current Loans Gross Loans Commercial real estate $ 1,124 $ 1,140 $ 8,506 $ 10,770 $ 926,151 $ 936,921 Commercial and industrial 1,218 691 4,323 6,232 452,321 458,553 Commercial construction 581 — 335 916 202,077 202,993 Residential 250 180 366 796 168,392 169,188 Home equity 622 — 288 910 82,463 83,373 Consumer 35 10 27 72 10,675 10,747 Total gross loans $ 3,830 $ 2,021 $ 13,845 $ 19,696 $ 1,842,079 $ 1,861,775
Impaired Financing Receivables	The following tables set forth the recorded investment in impaired loans and the related specific allowance allocated as of the dates indicated. Balance at March 31, 2016 (Dollars in thousands) Unpaid contractual principal balance Total recorded investment in impaired loans Recorded investment with no allowance Recorded investment with allowance Related specific allowance Commercial real estate $ 11,810 $ 9,926 $ 9,165 $ 761 $ 179 Commercial and industrial 9,932 7,853 4,615 3,238 1,420 Commercial construction 3,024 2,989 1,552 1,437 488 Residential 395 307 307 — — Home equity 450 309 309 — — Consumer 23 21 — 21 21 Total $ 25,634 $ 21,405 $ 15,948 $ 5,457 $ 2,108 Balance at December 31, 2015 (Dollars in thousands) Unpaid contractual principal balance Total recorded investment in impaired loans Recorded investment with no allowance Recorded investment with allowance Related specific allowance Commercial real estate $ 14,903 $ 12,287 $ 11,734 $ 553 $ 186 Commercial and industrial 9,816 7,810 5,253 2,557 1,078 Commercial construction 3,147 3,032 1,583 1,449 499 Residential 453 366 366 — — Home equity 308 169 164 5 5 Consumer 25 24 — 24 24 Total $ 28,652 $ 23,688 $ 19,100 $ 4,588 $ 1,792 The following table presents the average recorded investment in impaired loans and the related interest recognized during the periods indicated: Three Months Ended March 31, 2016 Three Months Ended March 31, 2015 (Dollars in thousands) Average recorded investment Interest income recognized Average recorded investment Interest income recognized Commercial real estate $ 9,668 $ 43 $ 15,479 $ 45 Commercial and industrial 8,424 26 11,256 34 Commercial construction 2,975 37 2,624 26 Residential 308 — 459 — Home equity 246 (2 ) 179 1 Consumer 22 — 49 — Total $ 21,643 $ 104 $ 30,046 $ 106
Troubled Debt Restructurings on Financing Receivables	Loans modified as troubled debt restructurings during the three months ended March 31, 2016 are detailed below. Three months ended March 31, 2016 (Dollars in thousands) Number of restructurings Pre-modification outstanding recorded investment Post-modification outstanding recorded investment Commercial real estate — $ — $ — Commercial and industrial 1 264 264 Commercial construction — — — Residential — — — Home equity — — — Consumer — — — Total 1 $ 264 $ 264 Loans modified as troubled debt restructurings during the three month period ended March 31, 2015 are detailed below. Three months ended March 31, 2015 (Dollars in thousands) Number of restructurings Pre-modification outstanding recorded investment Post-modification outstanding recorded investment Commercial real estate — $ — $ — Commercial and industrial 4 869 869 Commercial construction — — — Residential — — — Home equity — — — Consumer — — — Total 4 $ 869 $ 869
Allowance for Credit Losses on Financing Receivables	Changes in the allowance for loan losses by segment for the three months ended months ended March 31, 2016 are presented below: (Dollars in thousands) Cmml Real Estate Cmml and Industrial Cmml Constr Resid. Mortgage Home Equity Consumer Total Beginning Balance at December 31, 2015 $ 13,514 $ 9,758 $ 3,905 $ 1,061 $ 540 $ 230 $ 29,008 Provision 294 463 64 16 6 7 850 Recoveries 19 129 — — — 2 150 Less: Charge offs — 72 5 — 5 16 98 Ending Balance at March 31, 2016 $ 13,827 $ 10,278 $ 3,964 $ 1,077 $ 541 $ 223 $ 29,910 Ending allowance balance: Allotted to loans individually evaluated for impairment $ 179 $ 1,420 $ 488 $ — $ — $ 21 $ 2,108 Allotted to loans collectively evaluated for impairment $ 13,648 $ 8,858 $ 3,476 $ 1,077 $ 541 $ 202 $ 27,802 Changes in the allowance for loan losses by segment for the three months ended months ended March 31, 2015 are presented below: (Dollars in thousands) Cmml Real Estate Cmml and Industrial Cmml Constr Resid. Mortgage Home Equity Consumer Total Beginning Balance at December 31, 2014 $ 12,664 $ 9,245 $ 3,384 $ 989 $ 608 $ 231 $ 27,121 Provision 78 530 11 (29 ) 7 28 625 Recoveries 5 84 13 — — 8 110 Less: Charge offs — 17 — — — 36 53 Ending Balance at March 31, 2015 $ 12,747 $ 9,842 $ 3,408 $ 960 $ 615 $ 231 $ 27,803 Ending allowance balance: Allotted to loans individually evaluated for impairment $ 165 $ 1,951 $ 528 $ — $ 22 $ 49 $ 2,715 Allotted to loans collectively evaluated for impairment $ 12,582 $ 7,891 $ 2,880 $ 960 $ 593 $ 182 $ 25,088

Deposits (Tables)

Deposits (Tables)	3 Months Ended
	Mar. 31, 2016
Deposits [Abstract]
Schedule of Deposit Liabilities	Deposits are summarized as follows: (Dollars in thousands) March 31, 2016 December 31, 2015 Non-interest bearing demand deposits $ 599,282 $ 570,589 Interest bearing checking 313,314 313,674 Savings 179,127 167,304 Money market 735,492 692,114 Certificates of deposit $250,000 or less 127,925 129,993 Certificates of deposit more than $250,000 43,309 37,704 Total non-brokered deposits (1) 1,998,449 1,911,378 Brokered deposits (2) 89,288 106,770 Total deposits $ 2,087,737 $ 2,018,148 (1) Includes reciprocal money market deposits and CDs received from participating banks in nationwide networks as a result of our customers electing to participate in programs to obtain full FDIC insurance. Essentially, the equivalent of the original deposit comes back to the Company as non-brokered deposits within the appropriate category under total deposits on the balance sheet. (2) Primarily brokered CDs $250,000 and under.

Derivatives and Hedging Activ25

Derivatives and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivatives, Fair Value and Classification	The table below presents the fair value and classification of the Company’s derivative financial instruments for the periods presented: As of March 31, 2016 As of December 31, 2015 (Dollars in thousands) Asset Derivatives Liability Derivatives Asset Derivatives Liability Derivatives Back-to-Back Swaps $ 225 $ 225 $ 16 $ 16
Schedule of Derivatives- Offsetting Assets and Liabilities	The table below also presents the offsetting of derivatives and amounts subject to master netting agreements not offset in the consolidated balance sheet at the dates indicated. March 31, 2016 Gross Amounts of Recognized Asset/Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets Presented in the Statement of Financial Position Gross amounts not offset in the Statement of Financial Position (Dollars in thousands) Financial Instruments Cash collateral (Received)/Posted Net Amount Asset Derivatives Back-to-Back Swaps $ 225 — $ 225 — — $ 225 Liability Derivatives Back-to-Back Swaps $ 225 — $ 225 — 240 $ (15 ) December 31, 2015 Gross Amounts of Recognized Asset/Liabilities Gross Amounts Offset in the Statement of Financial Position Net Amounts of Assets Presented in the Statement of Financial Position Gross amounts not offset in the Statement of Financial Position (Dollars in thousands) Financial Instruments Cash collateral (Received)/Posted Net Amount Asset Derivatives Back-to-Back Swaps $ 16 — $ 16 — — $ 16 Liability Derivatives Back-to-Back Swaps $ 16 — $ 16 — — $ 16

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The table below provides a summary of the options granted in 2016 and 2015 . Three Months Ended March 31, 2016 2015 Options granted 30,613 27,115 Term in years 10 10 Average assumptions used in the fair value model: Expected volatility 42 % 47 % Expected dividend yield 3.03 % 2.89 % Expected life in years 7 7 Risk-free interest rate 1.91 % 1.95 % Market price on date of grant $ 21.86 $ 21.03 Per share weighted average fair value $ 7.90 $ 8.51 Fair value as a percentage of market value at grant date 36 % 40 %
Schedule of Restricted Stock Awards Granted	The table below provides a summary of restricted stock awards granted in 2016 and 2015 . Three Months Ended March 31, Restricted Stock Awards 2016 2015 Two Year Vesting 9,060 7,276 Four Year Vesting 17,453 17,181 Performance-Based Vesting 35,071 30,262 Total Restricted Stock Awards 61,584 54,719 Weighted average grant date fair value $ 21.86 $ 21.03

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Schedule of Weighted Average Number of Shares	The table below presents the increase in average shares outstanding, using the treasury stock method, for the diluted earnings per share calculation for the periods indicated: Three Months Ended March 31, 2016 2015 Basic weighted average common shares outstanding 10,405,112 10,243,044 Dilutive shares 66,672 67,430 Diluted weighted average common shares outstanding 10,471,784 10,310,474

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring and Nonrecurring Basis	The following tables summarize significant assets and liabilities carried at fair value and placement in the fair value hierarchy at the dates specified: March 31, 2016 Fair Value Measurements using: (Dollars in thousands) Fair Value (level 1) (level 2) (level 3) Assets measured on a recurring basis: Fixed income securities $ 292,500 $ — $ 292,500 $ — Equity securities 12,446 12,446 — — FHLB stock 2,793 — — 2,793 Interest-rate swaps 225 — 225 — Assets measured on a non-recurring basis: Impaired loans (collateral dependent) 3,088 — — 3,088 Liabilities measured on a recurring basis Interest-rate swaps 225 — 225 — December 31, Fair Value Measurements using: (Dollars in thousands) Fair Value (level 1) (level 2) (level 3) Assets measured on a recurring basis: Fixed income securities $ 288,701 $ — $ 288,701 $ — Equity securities 11,657 11,657 — — FHLB stock 3,050 — — 3,050 Interest-rate swaps 16 — 16 — Assets measured on a non-recurring basis: Impaired loans (collateral dependent) 2,516 — — 2,516 Liabilities measured on a recurring basis Interest-rate swaps 16 — 16 —
Quantitative Information About Significant Unobservable Inputs for Fair Value Measurements	The following table presents additional quantitative information about assets measured at fair value on a recurring and non-recurring basis for which the Company utilized Level 3 inputs (significant unobservable inputs for situations in which there is little, if any, market activity for the asset or liability) to determine fair value as of March 31, 2016 (Dollars in thousands) Fair Value Valuation Technique Unobservable Input Unobservable Input Value or Range Assets measured on a recurring basis: FHLB stock $2,793 FHLB Stated Par Value N/A N/A Assets measured on a non-recurring basis: Impaired loans (collateral dependent) $3,088 Appraisal of collateral Appraisal adjustments (1) 5% - 50% (1) Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses.
Fair Value, by Balance Sheet Grouping	The carrying values, estimated fair values and placement in the fair value hierarchy of the Company's financial instruments for which fair value is only disclosed but not recognized on the balance sheet at the dates indicated are summarized as follows: March 31, 2016 Fair value measurement (Dollars in thousands) Carrying Amount Fair Value Level 1 inputs Level 2 Inputs Level 3 Inputs Financial assets: Loans held for sale $ 770 $ 771 $ — $ 771 $ — Loans, net 1,834,782 1,850,258 — — 1,850,258 Financial liabilities: Certificates of deposit (including brokered) 260,522 260,636 — 260,636 — Borrowed funds 671 671 — 671 — Subordinated debt 14,825 14,758 — — 14,758 December 31, 2015 Fair value measurement (Dollars in thousands) Carrying Amount Fair Value Level 1 inputs Level 2 Inputs Level 3 Inputs Financial assets: Loans held for sale $ 1,709 $ 1,709 $ — $ 1,709 $ — Loans, net 1,830,954 1,845,009 — — 1,845,009 Financial liabilities: Certificates of deposit (including brokered) 274,467 273,419 — 273,419 — Borrowed funds 53,671 53,670 — 53,670 — Subordinated debt 14,822 13,961 — — 13,961

Summary of Significant Accoun29

Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2016branchessegment	Apr. 21, 2016USD ($)$ / shares
Summary of Significant Accounting Policies [Line Items]
Number of branches | branches	22
Reportable operating segments | segment	1
Subsequent Event
Summary of Significant Accounting Policies [Line Items]
Price Per Share, subcription rights and community offering | $ / shares		$ 21.50
Minimum | Subsequent Event
Summary of Significant Accounting Policies [Line Items]
Intended capital to be raised subscription rights and community offeriing		$ 10
Maximum | Subsequent Event
Summary of Significant Accounting Policies [Line Items]
Intended capital to be raised subscription rights and community offeriing		$ 12

Investments Available-for-sale

Investments Available-for-sale (Details) $ in Thousands		Mar. 31, 2016USD ($)investments	Dec. 31, 2015USD ($)
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Fair Value		$ 304,946	$ 300,358
Securities pledged as collateral		290,500
Total fixed income securities
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost		287,475	286,838
Unrealized gains		5,300	3,159
Unrealized losses		275	1,296
Fair Value		292,500	288,701
Federal Agency Obligations
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost	[1]	78,640	78,626
Unrealized gains	[1]	1,097	352
Unrealized losses	[1]	19	153
Fair Value	[1]	79,718	78,825
Residential federal agency MBS
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost	[1]	72,069	75,105
Unrealized gains	[1]	844	406
Unrealized losses	[1]	184	648
Fair Value	[1]	72,729	74,863
Collateralized Mortgage Obligations
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Fair Value		20,000	20,800
Commercial federal agency MBS
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost	[1]	27,499	23,908
Unrealized gains	[1]	286	0
Unrealized losses	[1]	0	363
Fair Value	[1]	27,785	23,545
Municipal securities
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost		97,040	96,189
Unrealized gains		2,928	2,357
Unrealized losses		43	35
Fair Value		99,925	98,511
Corporate bonds
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost		10,284	10,257
Unrealized gains		128	44
Unrealized losses		29	95
Fair Value		10,383	10,206
Certificates of Deposit
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost	[2]	1,943	2,753
Unrealized gains	[2]	17	0
Unrealized losses	[2]	0	2
Fair Value	[2]	1,960	2,751
Equity investments
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost		10,969	10,043
Unrealized gains		1,879	1,966
Unrealized losses		402	352
Fair Value		$ 12,446	11,657
Percent of portfolio invested in financial services		16.00%
Fixed Income and Equity Securities, Excluding CDs
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Unrealized losses		$ 677
Number of securities in loss position | investments		36
Investments Temporarily Impaired, Fair Value		$ 28,600
Number of securities in a loss position, 12 months or longer | investments		9
Investments Temporarily Impaired, 12 months or longer, Unrealized Losses		$ 194
Total available for sale securities, at fair value
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]
Amortized cost		298,444	296,881
Unrealized gains		7,179	5,125
Unrealized losses		677	1,648
Fair Value		$ 304,946	$ 300,358
[1]	These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae ("FNMA"), Freddie Mac ("FHLMC"), Federal Farm Credit Bank ("FFCB"), or one of several Federal Home Loan Banks, as well as, investments guaranteed by Ginnie Mae ("GNMA"), a wholly-owned government entity.
[2]	Certificates of deposits ("CDs") represent term deposits issued by banks that are subject to FDIC insurance and purchased on the open market.

Investments Maturities (Details

Investments Maturities (Details) $ in Thousands	Mar. 31, 2016USD ($)
Schedule of Available-for-sale Securities [Line Items]
Callable Securities, Fair Value	$ 49,400
Total fixed income securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 14,789
Amortized Cost, Within One Year, Yield	1.48%
Fair Value, Within One Year	$ 14,841
Amortized Cost Basis, After One, But Within Five Years	$ 97,093
Amortized Cost Basis, After One, But Within Five Years, Yield	2.21%
Fair Value, After One, But Within Five Years	$ 98,726
Amortized Cost, After Five, But Within Ten Years	$ 76,485
Amortized Cost, After Five, But Within Ten Years, Yield	2.90%
Fair Value, after Five but Within Ten Years	$ 78,292
Amortized Cost Basis, After Ten Years	$ 99,108
Amortized Cost after Ten Years, Yield	2.67%
Fair Value, After Ten Years	$ 100,641
Federal agency obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 7,035
Amortized Cost, Within One Year, Yield	0.91%
Amortized Cost Basis, After One, But Within Five Years	$ 62,054
Amortized Cost Basis, After One, But Within Five Years, Yield	1.59%
Amortized Cost, After Five, But Within Ten Years	$ 9,551
Amortized Cost, After Five, But Within Ten Years, Yield	2.22%
Amortized Cost Basis, After Ten Years	$ 0
Amortized Cost after Ten Years, Yield	0.00%
Residential federal agency MBS
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 0
Amortized Cost, Within One Year, Yield	0.00%
Amortized Cost Basis, After One, But Within Five Years	$ 3,101
Amortized Cost Basis, After One, But Within Five Years, Yield	3.17%
Amortized Cost, After Five, But Within Ten Years	$ 1,242
Amortized Cost, After Five, But Within Ten Years, Yield	1.91%
Amortized Cost Basis, After Ten Years	$ 67,726
Amortized Cost after Ten Years, Yield	2.13%
Commercial federal agency MBS
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 0
Amortized Cost, Within One Year, Yield	0.00%
Amortized Cost Basis, After One, But Within Five Years	$ 0
Amortized Cost Basis, After One, But Within Five Years, Yield	0.00%
Amortized Cost, After Five, But Within Ten Years	$ 27,499
Amortized Cost, After Five, But Within Ten Years, Yield	2.26%
Amortized Cost Basis, After Ten Years	$ 0
Amortized Cost after Ten Years, Yield	0.00%
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 6,233
Amortized Cost, Within One Year, Yield	2.31%
Amortized Cost Basis, After One, But Within Five Years	$ 25,813
Amortized Cost Basis, After One, But Within Five Years, Yield	3.58%
Amortized Cost, After Five, But Within Ten Years	$ 33,612
Amortized Cost, After Five, But Within Ten Years, Yield	3.65%
Amortized Cost Basis, After Ten Years	$ 31,382
Amortized Cost after Ten Years, Yield	3.85%
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 528
Amortized Cost, Within One Year, Yield	1.33%
Amortized Cost Basis, After One, But Within Five Years	$ 5,175
Amortized Cost Basis, After One, But Within Five Years, Yield	2.15%
Amortized Cost, After Five, But Within Ten Years	$ 4,581
Amortized Cost, After Five, But Within Ten Years, Yield	2.94%
Amortized Cost Basis, After Ten Years	$ 0
Amortized Cost after Ten Years, Yield	0.00%
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost, Within One Year	$ 993
Amortized Cost, Within One Year, Yield	0.34%
Amortized Cost Basis, After One, But Within Five Years	$ 950
Amortized Cost Basis, After One, But Within Five Years, Yield	2.13%
Amortized Cost, After Five, But Within Ten Years	$ 0
Amortized Cost, After Five, But Within Ten Years, Yield	0.00%
Amortized Cost Basis, After Ten Years	$ 0
Amortized Cost after Ten Years, Yield	0.00%

Loans - Balance by Class of Loa

Loans - Balance by Class of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Schedule of Loans by Loan Classification [Line Items]
Gross loans	$ 1,866,346	$ 1,861,775
Deferred loan origination fees, net	(1,654)	(1,813)
Total loans	1,864,692	1,859,962
Allowance for loan losses	(29,910)	(29,008)	$ (27,803)	$ (27,121)
Net Loans	1,834,782	1,830,954
Commercial
Schedule of Loans by Loan Classification [Line Items]
Gross loans	1,600,557	1,598,467
Commercial real estate
Schedule of Loans by Loan Classification [Line Items]
Gross loans	936,907	936,921
Allowance for loan losses	(13,827)	(13,514)	(12,747)	(12,664)
Commercial and industrial
Schedule of Loans by Loan Classification [Line Items]
Gross loans	456,436	458,553
Allowance for loan losses	(10,278)	(9,758)	(9,842)	(9,245)
Commercial construction
Schedule of Loans by Loan Classification [Line Items]
Gross loans	207,214	202,993
Allowance for loan losses	(3,964)	(3,905)	(3,408)	(3,384)
Retail
Schedule of Loans by Loan Classification [Line Items]
Gross loans	265,789	263,308
Residential
Schedule of Loans by Loan Classification [Line Items]
Gross loans	170,585	169,188
Allowance for loan losses	(1,077)	(1,061)	(960)	(989)
Home Equity
Schedule of Loans by Loan Classification [Line Items]
Gross loans	84,665	83,373
Allowance for loan losses	(541)	(540)	(615)	(608)
Consumer
Schedule of Loans by Loan Classification [Line Items]
Gross loans	10,539	10,747
Allowance for loan losses	$ (223)	$ (230)	$ (231)	$ (231)

Loans - Loan Categories Narrati

Loans - Loan Categories Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2016USD ($)payment	Dec. 31, 2015USD ($)
Commercial
Schedule of Loans by Loan Classification [Line Items]
Participation loans amount	$ 59.6	$ 62.3
Participations loans sold that are still serviced amount	$ 53.1	52.7
Commercial real estate | Minimum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	15 years
Commercial real estate | Maximum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	25 years
Commercial and industrial | Minimum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	1 year
Commercial and industrial | Maximum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	7 years
Commercial construction | Minimum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	1 year
Commercial construction | Maximum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	3 years
Residential
Schedule of Loans by Loan Classification [Line Items]
Early Payment Default Period | payment	4
Amount of loans serviced for others	$ 18.2	$ 18.5
Residential | Maximum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	30 years
Home Equity | Maximum
Schedule of Loans by Loan Classification [Line Items]
Loan-to-value ratio	80.00%
Home Equity Loans | Minimum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	3 years
Period a loan has a fixed rate	3 years
Home Equity Loans | Maximum
Schedule of Loans by Loan Classification [Line Items]
Repayment period, term of loan	15 years
Period a loan has a fixed rate	15 years
Home equity lines of credit
Schedule of Loans by Loan Classification [Line Items]
Term of interest only payments	10 years
Term of Principal and Interest Payments after Interest only term	15 years
Multi-family owner occupied residential property | Minimum
Schedule of Loans by Loan Classification [Line Items]
Loan-to-value ratio	75.00%
Single family owner occupied residential property | Maximum
Schedule of Loans by Loan Classification [Line Items]
Loan-to-value ratio	97.00%

Loans - Loans Serving as Collat

Loans - Loans Serving as Collateral (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financial Instruments Owned and Pledged as Collateral [Line Items]
Loans pledged to the FHLB for borrowing capacity	$ 413,149	$ 414,629
Commercial real estate
Financial Instruments Owned and Pledged as Collateral [Line Items]
Loans pledged to the FHLB for borrowing capacity	277,056	281,802
Residential
Financial Instruments Owned and Pledged as Collateral [Line Items]
Loans pledged to the FHLB for borrowing capacity	122,744	118,855
Home Equity
Financial Instruments Owned and Pledged as Collateral [Line Items]
Loans pledged to the FHLB for borrowing capacity	$ 13,349	$ 13,972

Allowance For Loan Loss - Evalu

Allowance For Loan Loss - Evaluation Method (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	$ 21,405	$ 23,688
Loans collectively evaluated for impairment	1,843,287	1,836,274
Gross loans	1,866,346	1,861,775
Deferred loan origination fees, net	(1,654)	(1,813)
Total loans	1,864,692	1,859,962
Commercial real estate
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	9,926	12,287
Loans collectively evaluated for impairment	926,981	924,634
Gross loans	936,907	936,921
Commercial and industrial
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	7,853	7,810
Loans collectively evaluated for impairment	448,583	450,743
Gross loans	456,436	458,553
Commercial construction
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	2,989	3,032
Loans collectively evaluated for impairment	204,225	199,961
Gross loans	207,214	202,993
Residential
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	307	366
Loans collectively evaluated for impairment	170,278	168,822
Gross loans	170,585	169,188
Home Equity
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	309	169
Loans collectively evaluated for impairment	84,356	83,204
Gross loans	84,665	83,373
Consumer
Schedule of Financing Receivable by Evaluation Method [Line Items]
Loans individually evaluated for impairment	21	24
Loans collectively evaluated for impairment	10,518	10,723
Gross loans	$ 10,539	$ 10,747

Allowance For Loan Loss - Adver

Allowance For Loan Loss - Adversely Classified Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Adversely classified loans to total loans	1.31%	1.33%
Gross loans	$ 1,866,346	$ 1,861,775
Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans	936,907	936,921
Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Gross loans	456,436	458,553
Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Gross loans	207,214	202,993
Residential
Financing Receivable, Recorded Investment [Line Items]
Gross loans	170,585	169,188
Home Equity
Financing Receivable, Recorded Investment [Line Items]
Gross loans	84,665	83,373
Consumer
Financing Receivable, Recorded Investment [Line Items]
Gross loans	10,539	10,747
Substandard
Financing Receivable, Recorded Investment [Line Items]
Gross loans	24,314	24,752
Substandard | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans	11,586	12,487
Substandard | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Gross loans	9,100	8,670
Substandard | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Gross loans	1,734	1,776
Substandard | Residential
Financing Receivable, Recorded Investment [Line Items]
Gross loans	1,213	1,278
Substandard | Home Equity
Financing Receivable, Recorded Investment [Line Items]
Gross loans	644	503
Substandard | Consumer
Financing Receivable, Recorded Investment [Line Items]
Gross loans	37	38
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Gross loans	53	11
Doubtful | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Doubtful | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Gross loans	42	0
Doubtful | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Doubtful | Residential
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Doubtful | Home Equity
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Doubtful | Consumer
Financing Receivable, Recorded Investment [Line Items]
Gross loans	11	11
Loss
Financing Receivable, Recorded Investment [Line Items]
Gross loans	3	8
Loss | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Loss | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Gross loans	3	3
Loss | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Loss | Residential
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Loss | Home Equity
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	5
Loss | Consumer
Financing Receivable, Recorded Investment [Line Items]
Gross loans	0	0
Not Adversely Classified
Financing Receivable, Recorded Investment [Line Items]
Gross loans	1,841,976	1,837,004
Not Adversely Classified | Commercial real estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans	925,321	924,434
Not Adversely Classified | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Gross loans	447,291	449,880
Not Adversely Classified | Commercial construction
Financing Receivable, Recorded Investment [Line Items]
Gross loans	205,480	201,217
Not Adversely Classified | Residential
Financing Receivable, Recorded Investment [Line Items]
Gross loans	169,372	167,910
Not Adversely Classified | Home Equity
Financing Receivable, Recorded Investment [Line Items]
Gross loans	84,021	82,865
Not Adversely Classified | Consumer
Financing Receivable, Recorded Investment [Line Items]
Gross loans	$ 10,491	$ 10,698

Allowance For Loan Loss - Past

Allowance For Loan Loss - Past Due and Non-Accrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Schedule of Aging of Financing Receivables [Line Items]
Number of days a loan must be paid current before accrual of interest is resumed	180 days
Non-accrual loans	$ 11,264	$ 13,845
Total Past Due Loans	18,152	19,696
Current Loans	1,848,194	1,842,079
Gross loans	$ 1,866,346	$ 1,861,775
The ratio of non-accrual loans to total loans	0.60%	0.74%	1.07%
Additional funding commitments for loans on non-accrual	$ 0
Commercial real estate
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	6,188	$ 8,506
Total Past Due Loans	11,251	10,770
Current Loans	925,656	926,151
Gross loans	936,907	936,921
Commercial and industrial
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	4,106	4,323
Total Past Due Loans	5,177	6,232
Current Loans	451,259	452,321
Gross loans	456,436	458,553
Commercial construction
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	213	335
Total Past Due Loans	388	916
Current Loans	206,826	202,077
Gross loans	207,214	202,993
Residential
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	307	366
Total Past Due Loans	860	796
Current Loans	169,725	168,392
Gross loans	170,585	169,188
Home Equity
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	424	288
Total Past Due Loans	424	910
Current Loans	84,241	82,463
Gross loans	84,665	83,373
Consumer
Schedule of Aging of Financing Receivables [Line Items]
Non-accrual loans	26	27
Total Past Due Loans	52	72
Current Loans	10,487	10,675
Gross loans	10,539	10,747
Financing Receivables, 30 to 59 Days Past Due
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	5,680	3,830
Financing Receivables, 30 to 59 Days Past Due | Commercial real estate
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	4,665	1,124
Financing Receivables, 30 to 59 Days Past Due | Commercial and industrial
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	833	1,218
Financing Receivables, 30 to 59 Days Past Due | Commercial construction
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	175	581
Financing Receivables, 30 to 59 Days Past Due | Residential
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	0	250
Financing Receivables, 30 to 59 Days Past Due | Home Equity
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	0	622
Financing Receivables, 30 to 59 Days Past Due | Consumer
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	7	35
Financing Receivables, 60 to 89 Days Past Due
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	1,208	2,021
Financing Receivables, 60 to 89 Days Past Due | Commercial real estate
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	398	1,140
Financing Receivables, 60 to 89 Days Past Due | Commercial and industrial
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	238	691
Financing Receivables, 60 to 89 Days Past Due | Commercial construction
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	0	0
Financing Receivables, 60 to 89 Days Past Due | Residential
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	553	180
Financing Receivables, 60 to 89 Days Past Due | Home Equity
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	0	0
Financing Receivables, 60 to 89 Days Past Due | Consumer
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	19	10
Not Adversely Classified
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	1,841,976	1,837,004
Non-accrual loans not adversely classified	337	402
Not Adversely Classified | Commercial real estate
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	925,321	924,434
Not Adversely Classified | Commercial and industrial
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	447,291	449,880
Not Adversely Classified | Commercial construction
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	205,480	201,217
Not Adversely Classified | Residential
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	169,372	167,910
Not Adversely Classified | Home Equity
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	84,021	82,865
Not Adversely Classified | Consumer
Schedule of Aging of Financing Receivables [Line Items]
Gross loans	$ 10,491	$ 10,698

Allowance For Loan Loss - Impai

Allowance For Loan Loss - Impaired Loans (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)relationship	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	$ 21,405		$ 23,688
Total accruing impaired loans	10,300		10,100
Impaired non-accrual loans	11,100		13,600
Unpaid contractual principal balance	25,634		28,652
Recorded investment with no allowance	15,948		19,100
Recorded investment with allowance	5,457		4,588
Related allowance	2,108	$ 2,700	1,792
Average recorded investment	21,643	30,046
Interest income recognized	104	106
Additional funding commitments on impaired loans	$ 469
Commercial
Financing Receivable, Impaired [Line Items]
Larger commercial relationships downgraded in the period | relationship	3
Commercial real estate
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	$ 9,926		12,287
Unpaid contractual principal balance	11,810		14,903
Recorded investment with no allowance	9,165		11,734
Recorded investment with allowance	761		553
Related allowance	179		186
Average recorded investment	9,668	15,479
Interest income recognized	43	45
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	$ 7,853		7,810
Larger C&I Relationship Downgraded in Period Requiring Additional Specific Reserves | relationship	1
Unpaid contractual principal balance	$ 9,932		9,816
Recorded investment with no allowance	4,615		5,253
Recorded investment with allowance	3,238		2,557
Related allowance	1,420		1,078
Average recorded investment	8,424	11,256
Interest income recognized	26	34
Commercial construction
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	2,989		3,032
Unpaid contractual principal balance	3,024		3,147
Recorded investment with no allowance	1,552		1,583
Recorded investment with allowance	1,437		1,449
Related allowance	488		499
Average recorded investment	2,975	2,624
Interest income recognized	37	26
Residential
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	307		366
Unpaid contractual principal balance	395		453
Recorded investment with no allowance	307		366
Recorded investment with allowance	0		0
Related allowance	0		0
Average recorded investment	308	459
Interest income recognized	0	0
Home Equity
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	309		169
Unpaid contractual principal balance	450		308
Recorded investment with no allowance	309		164
Recorded investment with allowance	0		5
Related allowance	0		5
Average recorded investment	246	179
Interest income recognized	(2)	1
Consumer
Financing Receivable, Impaired [Line Items]
Total recorded investment in impaired loans	21		24
Unpaid contractual principal balance	23		25
Recorded investment with no allowance	0		0
Recorded investment with allowance	21		24
Related allowance	21		$ 24
Average recorded investment	22	49
Interest income recognized	$ 0	$ 0

Allowance For Loan Loss - Troub

Allowance For Loan Loss - Troubled Debt Restructures (Details)	3 Months Ended
	Mar. 31, 2016USD ($)restructuring	Mar. 31, 2015USD ($)restructuring	Dec. 31, 2015USD ($)
Financing Receivable, Modifications [Line Items]
Total Troubled Debt Restructure (TDR) loans	$ 15,600,000		$ 17,100,000
TDR loans on accrual status	10,300,000		10,100,000
TDR loans included in non-performing loans	5,300,000		$ 7,100,000
Additional Funding Commitments on TDR loans	$ 469,000
Number of restructurings | restructuring	1	4
Pre-modification outstanding recorded investment	$ 264,000	$ 869,000
Post-modification outstanding recorded investment	$ 264,000	$ 869,000
Number of TDRs that defaulted | restructuring	0	0
Charge-offs associated with TDRs	$ 0	$ 0
Specific reserves allocated to TDRs	$ 0	61,000
Interest payments received on nonaccruing TDR loans excluded from income		$ 1,000
Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	$ 0	$ 0
Commercial and industrial
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	1	4
Pre-modification outstanding recorded investment	$ 264,000	$ 869,000
Post-modification outstanding recorded investment	$ 264,000	$ 869,000
Commercial construction
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	$ 0	$ 0
Residential
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	$ 0	$ 0
Home Equity
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	$ 0	$ 0
Consumer
Financing Receivable, Modifications [Line Items]
Number of restructurings | restructuring	0	0
Pre-modification outstanding recorded investment	$ 0	$ 0
Post-modification outstanding recorded investment	$ 0	$ 0

Allowance For Loan Loss - Other

Allowance For Loan Loss - Other Real Estate Owned (Details)	3 Months Ended
	Mar. 31, 2016USD ($)property	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carry value of OREO	$ 0		$ 0
Net gains on sales of OREO	$ 0	$ 154,000
Other real estate owned
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of OREO properties added | property	0
OREO fair value adjustment	$ 0	$ 0

Allowance For Loan Loss - Allow

Allowance For Loan Loss - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Increase (Decrease) in Loans	$ 4,700	$ 9,500
The ratio of non-accrual loans to total loans	0.60%	1.07%	0.74%
Allowance for loan losses on impaired loans	$ 2,108	$ 2,700	$ 1,792
Allowance for loan losses on non-impaired classified loans	2,200	1,600
Net charge-offs (recoveries)	$ (52)	$ (57)
Allowance for loan losses to total loans ratio	1.60%	1.65%	1.56%
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 29,008	$ 27,121
Provision for loan losses	850	625
Recoveries	150	110
Less: Charge offs	98	53
Ending Balance	29,910	27,803
Allotted to loans individually evaluated for impairment	2,108	2,715
Allotted to loans collectively evaluated for impairment	27,802	25,088
Commercial real estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	179		$ 186
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	13,514	12,664
Provision for loan losses	294	78
Recoveries	19	5
Less: Charge offs	0	0
Ending Balance	13,827	12,747
Allotted to loans individually evaluated for impairment	179	165
Allotted to loans collectively evaluated for impairment	13,648	12,582
Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	1,420		1,078
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	9,758	9,245
Provision for loan losses	463	530
Recoveries	129	84
Less: Charge offs	72	17
Ending Balance	10,278	9,842
Allotted to loans individually evaluated for impairment	1,420	1,951
Allotted to loans collectively evaluated for impairment	8,858	7,891
Commercial construction
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	488		499
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	3,905	3,384
Provision for loan losses	64	11
Recoveries	0	13
Less: Charge offs	5	0
Ending Balance	3,964	3,408
Allotted to loans individually evaluated for impairment	488	528
Allotted to loans collectively evaluated for impairment	3,476	2,880
Residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	0		0
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	1,061	989
Provision for loan losses	16	(29)
Recoveries	0	0
Less: Charge offs	0	0
Ending Balance	1,077	960
Allotted to loans individually evaluated for impairment	0	0
Allotted to loans collectively evaluated for impairment	1,077	960
Home Equity
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	0		5
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	540	608
Provision for loan losses	6	7
Recoveries	0	0
Less: Charge offs	5	0
Ending Balance	541	615
Allotted to loans individually evaluated for impairment	0	22
Allotted to loans collectively evaluated for impairment	541	593
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses on impaired loans	21		$ 24
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	230	231
Provision for loan losses	7	28
Recoveries	2	8
Less: Charge offs	16	36
Ending Balance	223	231
Allotted to loans individually evaluated for impairment	21	49
Allotted to loans collectively evaluated for impairment	$ 202	$ 182

Deposits (Details)

Deposits (Details) - USD ($) $ in Thousands		Mar. 31, 2016	Dec. 31, 2015
Deposits [Abstract]
Noninterest-bearing demand deposits		$ 599,282	$ 570,589
Interest bearing checking		313,314	313,674
Savings		179,127	167,304
Money markets		735,492	692,114
Certificates of deposit, $250,000 or Less,		127,925	129,993
Certificates of deposit more than $250,000		43,309	37,704
Total non-brokered deposits	[1]	1,998,449	1,911,378
Brokered deposits	[2]	89,288	106,770
Deposits		$ 2,087,737	$ 2,018,148
[1]	Includes reciprocal money market deposits and CDs received from participating banks in nationwide networks as a result of our customers electing to participate in programs to obtain full FDIC insurance. Essentially, the equivalent of the original deposit comes back to the Company as non-brokered deposits within the appropriate category under total deposits on the balance sheet.
[2]	Primarily brokered CDs $250,000 and under.

Borrowed Funds and Subordinat43

Borrowed Funds and Subordinated Debt (Details) - USD ($)	1 Months Ended		3 Months Ended
	Jan. 31, 2015	Mar. 31, 2000	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Borrowed Funds			$ 671,000	$ 53,671,000
Advances from Federal Home Loan Banks				40,700,000
Other Borrowings				13,000,000
Subordinated debt			$ 14,825,000	$ 14,822,000
Proceeds from capital contributions		$ 325,000
Junior subordinated debt, amount		$ 10,800,000
Fixed-to Floating Rate Subordinated Notes
Debt Instrument [Line Items]
Subordinated debt	$ 15,000,000
Subordinated debt, rate			6.00%
Original debt issuance costs	$ 190,000
Junior Subordinated Debt
Debt Instrument [Line Items]
Subordinated debt, rate		10.88%
Enterprise (MA) Capital Trust 1
Debt Instrument [Line Items]
Trust preferred securities, value		$ 10,500,000
Trust preferred securities, stated interest rate		10.88%
London Interbank Offered Rate (LIBOR) | Fixed-to Floating Rate Subordinated Notes
Debt Instrument [Line Items]
Fixed to Floating Rate Conversion Date			Jan. 31, 2025
Spread over LIBOR fixed-to floating rate note, rate			3.90%

Derivatives and Hedging Activ44

Derivatives and Hedging Activities (Details) - Interest rate swap	3 Months Ended
	Mar. 31, 2016USD ($)instrument	Dec. 31, 2015USD ($)instrument
Derivative [Line Items]
Number of Interest Rate Swaps | instrument	2	2
Aggregate notional value of interest-rate swaps	$ 10,100,000
Fair Value of Interest-Rate Swap Assets	225,000	$ 16,000
Fair Value of Interest-Rate Swap Liability	225,000	16,000
Gain (Loss) on Interest Rate Swaps	0
Gross Amount Interest Rate Swap Asset Recognized	225,000	16,000
Net Asset Amount, Interest Rate Swap	225,000	16,000
Gross Amount Interest Rate Swap Liability Recognized	225,000	16,000
Collateral posted	240,000	0
Net Liability Amount, Interest Rate Swap	$ (15,000)	$ 16,000

Supplemental Retirement Plan 45

Supplemental Retirement Plan and Other Postretirement Benefit Obligations (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)officer	Mar. 31, 2015USD ($)
Supplemental Employee Retirement Plan
Defined Benefit Plan Disclosures [Line Items]
Number of Active Executive Officers under Plan | officer	2
Number of Former Executive Officers under Plan | officer	1
Term of SERP benefits	20 years
Net Periodic Benefit Cost, Interest Only	$ 31	$ 31
Benefits Paid	69	69
Remaining accrual for benefit obligation in current year	93
Supplemental Life Insurance
Defined Benefit Plan Disclosures [Line Items]
Net Periodic Benefit Cost, Interest Only	$ 19	$ 18

Stock-Based Compensation Summar

Stock-Based Compensation Summary Information for Options Granted (Details) - $ / shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards granted	30,613	27,115
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term in years	10 years	10 years
Expected volatility	42.00%	47.00%
Market price on date of grant	$ 21.86	$ 21.03
Per share weighted average fair value	$ 7.90	$ 8.51
Weighted Average | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	3.03%	2.89%
Expected life in years	7 years	7 years
Risk-free interest rate	1.91%	1.95%
Fair Value as a percentage of market value at grant date	36.00%	40.00%

Stock-Based Compensation Stock

Stock-Based Compensation Stock Options, Stock Awards, and Stock in Lieu of Directors' Fees (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2016shares	Mar. 31, 2016USD ($)plansshares	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)	May. 31, 2016shares	Jan. 02, 2015$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Individual Stock Incentive Plans | plans		3
Stock-based compensation expense		$ 443	$ 488
Number of shares issued in lieu of cash to directors | shares	10,657
Fair market share price | $ / shares						$ 23.86
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 79	97
Restricted stock | Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		4 years
Restricted stock | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		2 years
Restricted stock and common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 294	309
Common stock in lieu of cash | Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 70	$ 82	$ 254
Vesting, Year Two | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting percentage		50.00%	50.00%
Vesting, Year Four | Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted, vesting percentage		50.00%	50.00%
2009 plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares remaining available for future grants | shares		107,992
Subsequent Event | 2016 plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares remaining available for future grants | shares					350,000

Stock-Based Compensation Restri

Stock-Based Compensation Restricted Stock Grants (Details) - Restricted stock - $ / shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards in period	61,584	54,719
Weighted Average Grant Date Fair Value, Stock Awards	$ 21.86	$ 21.03
Director | Two year vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards in period	9,060	7,276
Employee | Four year vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards in period	17,453	17,181
Employee | Performance-based vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock awards in period	35,071	30,262

Earnings Per Share Earnings Per

Earnings Per Share Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Basic weighted average common shares outstanding	10,405,112	10,243,044
Dilutive shares	66,672	67,430
Diluted weighted average common shares outstanding	10,471,784	10,310,474

Fair Value Measurements - Recur

Fair Value Measurements - Recurring and Nonrecurring Basis (Details)	3 Months Ended
	Mar. 31, 2016USD ($)property	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Specific allowance for collateral dependent impaired loans	$ 1,200,000		$ 1,400,000
Carry value of OREO	0		0
Net gains on sales of OREO	$ 0	$ 154,000
Financial Standby Letter of Credit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortization period of estimated fair value on standby letters of credit	1 year
Other real estate owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of OREO properties added | property	0
OREO fair value adjustment	$ 0	$ 0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	12,446,000		11,657,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | FHLB Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities	225,000		16,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	292,500,000		288,701,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | FHLB Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	225,000		16,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | FHLB Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	2,793,000		3,050,000
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	0		0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent), Fair Value	0		0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent), Fair Value	0		0
Fair Value, Measurements, Nonrecurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent), Fair Value	3,088,000		2,516,000
Fair Value | Fair Value, Measurements, Recurring | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of liabilities	225,000		16,000
Fair Value | Fair Value, Measurements, Recurring | Fixed income securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	292,500,000		288,701,000
Fair Value | Fair Value, Measurements, Recurring | Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	12,446,000		11,657,000
Fair Value | Fair Value, Measurements, Recurring | FHLB Stock
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	2,793,000		3,050,000
Fair Value | Fair Value, Measurements, Recurring | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of assets	225,000		16,000
Fair Value | Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent), Fair Value	$ 3,088,000		$ 2,516,000

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring | FHLB Stock
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value of assets		$ 2,793	$ 3,050
Fair Value, Measurements, Recurring | FHLB Stock | FHLB par stated value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value of assets		2,793
Fair Value, Measurements, Nonrecurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans (collateral dependent), Fair Value		3,088	$ 2,516
Fair Value, Measurements, Nonrecurring | Impaired loans (collateral dependent) | Appraisal of collateral
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Impaired loans (collateral dependent), Fair Value	[1]	$ 3,088
Fair Value, Measurements, Nonrecurring | Impaired loans (collateral dependent) | Appraisal of collateral | Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable Input Value or Range		5.00%
Fair Value, Measurements, Nonrecurring | Impaired loans (collateral dependent) | Appraisal of collateral | Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unobservable Input Value or Range		50.00%
[1]	Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses.

Fair Value Measurements - Balan

Fair Value Measurements - Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Carrying Amount
Financial assets:
Loans held for sale	$ 770	$ 1,709
Loans, net	1,834,782	1,830,954
Financial liabilities:
Borrowed Funds	671	53,671
Subordinated debt	14,825	14,822
Carrying Amount | Certificates of Deposit
Financial liabilities:
Certificates of deposit	260,522	274,467
Fair Value
Financial assets:
Loans held for sale	771	1,709
Loans, net	1,850,258	1,845,009
Financial liabilities:
Borrowed Funds	671	53,670
Subordinated debt	14,758	13,961
Fair Value | Certificates of Deposit
Financial liabilities:
Certificates of deposit	260,636	273,419
Fair Value, Inputs, Level 1
Financial assets:
Loans held for sale	0	0
Loans, net	0	0
Financial liabilities:
Borrowed Funds	0	0
Subordinated debt	0	0
Fair Value, Inputs, Level 1 | Certificates of Deposit
Financial liabilities:
Certificates of deposit	0	0
Fair Value, Inputs, Level 2
Financial assets:
Loans held for sale	771	1,709
Loans, net	0	0
Financial liabilities:
Borrowed Funds	671	53,670
Subordinated debt	0	0
Fair Value, Inputs, Level 2 | Certificates of Deposit
Financial liabilities:
Certificates of deposit	260,636	273,419
Fair Value, Inputs, Level 3
Financial assets:
Loans held for sale	0	0
Loans, net	1,850,258	1,845,009
Financial liabilities:
Borrowed Funds	0	0
Subordinated debt	14,758	13,961
Fair Value, Inputs, Level 3 | Certificates of Deposit
Financial liabilities:
Certificates of deposit	$ 0	$ 0