Enterprise Bancorp (EBTC) 10-Q 7 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Nov. 03, 2014
Document and Entity Information [Abstract]	'	'
Entity Registrant Name	'ENTERPRISE BANCORP INC /MA/	'
Entity Central Index Key	'0001018399	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Amendment Flag	'false	'
Entity Common Stock, Shares Outstanding	'	10,164,892

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Cash and cash equivalents:	'	'
Cash and due from banks	$49,310	$41,362
Interest-earning deposits	5,457	10,153
Fed funds sold	0	2,218
Total cash and cash equivalents	54,767	53,733
Investment securities at fair value	236,753	215,369
Federal Home Loan Bank Stock	3,357	4,324
Loans held for sale	1,645	1,255
Loans, less allowance for loan losses of $27,029 at September 30, 2014 and $26,967 at December 31, 2013	1,585,745	1,497,089
Premises and equipment	30,000	29,891
Accrued interest receivable	6,684	6,186
Deferred income taxes, net	12,645	13,927
Bank-owned life insurance	16,215	15,902
Prepaid income taxes	1,636	443
Prepaid expenses and other assets	7,592	6,150
Goodwill	5,656	5,656
Total assets	1,962,695	1,849,925
Liabilities	'	'
Deposits	1,768,796	1,635,992
Borrowed funds	1,004	36,534
Junior subordinated debentures	10,825	10,825
Accrued expenses and other liabilities	19,317	14,675
Accrued interest payable	251	565
Total liabilities	1,800,193	1,698,591
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; 10,153,933 shares issued and outstanding at September 30, 2014 (including 159,828 shares of unvested participating restricted awards) and 9,992,560 shares issued and outstanding at December 31, 2013 (including 170,365 shares of unvested participating restricted awards)	102	100
Additional paid-in-capital	55,763	52,936
Retained earnings	103,172	96,153
Accumulated other comprehensive income	3,465	2,145
Total stockholders' equity	162,502	151,334
Total liabilities and stockholders' equity	$1,962,695	$1,849,925

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]	'	'
Allowance for loan losses	$27,029	$26,967
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares issued	10,153,933	9,992,560
Common stock, shares outstanding	10,153,933	9,992,560
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	159,828	170,365

Consolidated_Statements_of_Inc

Consolidated Statements of Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Interest and dividend income:	'	'	'	'
Loans and loans held for sale	$18,234	$17,104	$53,117	$50,130
Investment securities	1,131	823	3,204	2,427
Other interest-earning assets	29	19	84	40
Total interest and dividend income	19,394	17,946	56,405	52,597
Interest expense:	'	'	'	'
Deposits	1,005	1,013	3,031	3,043
Borrowed funds	3	6	33	92
Junior subordinated debentures	294	294	883	883
Total interest expense	1,302	1,313	3,947	4,018
Net interest income	18,092	16,633	52,458	48,579
Provision for loan losses	765	583	1,165	1,900
Net interest income after provision for loan losses	17,327	16,050	51,293	46,679
Non-interest income:	'	'	'	'
Investment advisory fees	1,202	1,102	3,451	3,163
Deposit and interchange fees	1,268	1,229	3,727	3,518
Income on bank-owned life insurance,net	99	111	313	346
Net gains on sales of investment securities	215	83	830	1,031
Gains on sales of loans	135	171	283	728
Other income	621	472	1,679	1,574
Total non-interest income	3,540	3,168	10,283	10,360
Non-interest expense:	'	'	'	'
Salaries and employee benefits	9,454	8,548	27,852	25,247
Occupancy and equipment expenses	1,588	1,449	4,881	4,508
Technology and telecommunications expenses	1,248	1,085	3,844	3,441
Advertising and public relations expenses	575	481	1,932	2,047
Audit, legal and other professional fees	453	439	1,294	1,264
Deposit insurance premiums	297	287	851	820
Supplies and postage expenses	257	232	776	719
Investment advisory and custodial expenses	143	134	409	394
Other operating expenses	1,100	1,126	3,546	3,256
Total non-interest expense	15,115	13,781	45,385	41,696
Income before income taxes	5,752	5,437	16,191	15,343
Provision for income taxes	1,921	1,904	5,540	5,298
Net income	$3,831	$3,533	$10,651	$10,045
Basic earnings per share	$0.38	$0.36	$1.05	$1.02
Diluted earnings per share	$0.37	$0.35	$1.05	$1.01
Basic weighted average common shares outstanding	10,143,055	9,932,060	10,099,593	9,824,984
Diluted weighted average common shares outstanding	10,228,501	10,026,588	10,184,264	9,909,019

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income	$3,831	$3,533	$10,651	$10,045
Other comprehensive income (loss), net of taxes:	'	'	'	'
Gross unrealized holding gains (losses) on investments arising during the period	-283	431	2,905	-1,955
Income tax (expense) benefit	113	-136	-1,049	748
Net unrealized holding gains (losses), net of tax	-170	295	1,856	-1,207
Less: Reclassification adjustment for net gains included in net income	'	'	'	'
Net realized gains on sales of securities during the period	215	83	830	1,031
Income tax expense	-75	-30	-294	-369
Reclassification adjustment for gains realized, net of tax	140	53	536	662
Total other comprehensive income (loss)	-310	242	1,320	-1,869
Comprehensive income	$3,521	$3,775	$11,971	$8,176

Consolidated_Statement_of_Chan

Consolidated Statement of Changes in Stockholders' Equity (USD $)	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income
In Thousands, unless otherwise specified
Balance, beginning at Dec. 31, 2013	$151,334	$100	$52,936	$96,153	$2,145
Increase (Decrease) in Stockholders' Equity	'	'	'	'	'
Net income	10,651	'	'	10,651	'
Other comprehensive income, net	1,320	'	'	'	1,320
Tax benefit from exercise of stock options	3	'	3	'	'
Common stock dividend paid ($0.36 per share)	-3,632	'	'	-3,632	'
Common stock issued under dividend reinvestment plan	917	1	916	'	'
Stock-based compensation	1,339	1	1,338	'	'
Stock options exercised, net	570	0	570	'	'
Balance, ending at Sep. 30, 2014	$162,502	$102	$55,763	$103,172	$3,465

Consolidated_Statement_of_Chan1

Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2014
Statement of Stockholders' Equity [Abstract]	'
Common stock dividend paid, per share	$0.36

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities	'	'
Net income	$10,651	$10,045
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Provision for loan losses	1,165	1,900
Depreciation and amortization	4,089	3,686
Stock-based compensation expense	1,325	1,239
Mortgage loans originated for sale	-13,948	-31,751
Proceeds from mortgage loans sold	13,841	39,975
Net gains on sales of loans	-283	-728
Net gains on sales of OREO	0	-121
Net gains on sales of investments	-830	-1,031
Income on bank-owned life insurance,net	-313	-346
OREO fair value adjustment	0	23
Changes in:	'	'
Accrued interest receivable	-498	-7
Prepaid expenses and other assets	-1,726	6,686
Deferred income taxes	527	176
Accrued expenses and other liabilities	5,083	3,599
Accrued interest payable	-314	-336
Net cash provided by operating activities	18,769	33,009
Cash flows from investing activities:	'	'
Proceeds from sales of investment securities available for sale	24,329	8,293
Net proceeds (purchases) from FHLB capital stock	967	-64
Proceeds from maturities, calls and pay-downs of investment securities	30,311	13,730
Purchase of investment securities	-74,752	-35,301
Net increase in loans	-90,316	-113,364
Additions to premises and equipment, net	-2,949	-4,281
Proceeds from OREO sales and payments	0	652
Purchase of OREO	-457	0
Net cash used in investing activities	-112,867	-130,335
Cash flows from financing activities:	'	'
Net increase in deposits	132,804	178,920
Net decrease in borrowed funds	-35,530	-24,660
Cash dividends paid	-3,632	-3,389
Proceeds from issuance of common stock	917	948
Proceeds from the exercise of stock options	570	1,655
Tax benefit from the exercise of stock options	3	24
Net cash provided by financing activities	95,132	153,498
Net increase in cash and cash equivalents	1,034	56,172
Cash and cash equivalents at beginning of period	53,733	52,735
Cash and cash equivalents at end of period	54,767	108,907
Supplemental financial data:	'	'
Cash Paid For: Interest	4,261	4,354
Cash Paid For: Income Taxes	6,175	5,634
Supplemental schedule of non-cash investing activity:	'	'
Purchases of investment securities not yet settled	0	400
Transfer from loans to other real estate owned	290	168
Transfer from loans to other assets	205	0
Capital expenditures incurred not yet paid	$276	$247

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2014
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, 2013 audited consolidated financial statements and notes thereto contained in the 2013 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 14, 2014.  The Company has not changed its reporting policies from those disclosed in its 2013 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.
	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, which hold various types of qualifying securities.  The security corporations 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 Merrimack Valley and North Central regions of Massachusetts and Southern New Hampshire. Through the Bank and its subsidiaries, the Company offers a range of commercial and consumer loan products, deposit and cash management products, 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.
	Pursuant to the Accounting Standards Codification (“ASC”) Topic 810 “Consolidation of Variable Interest Entities,” issued by the Financial Accounting Standards Board (“FASB”), the Company carries Junior Subordinated Debentures as a liability on its consolidated interim 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, are excluded from the Company’s consolidated interim financial statements.
	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. 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 estimates and assumptions 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 2013 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 2013 Annual Report on Form 10-K for significant accounting policies. The Company has not changed its significant accounting policies from those disclosed in its 2013 Annual Report filed on Form 10-K.
	(c) Reporting Comprehensive Income
	Comprehensive income is defined as all changes to 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 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 ongoing 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, primarily due 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 September 30, 2014.  The Company is subject to U.S. federal and state income tax examinations by taxing authorities for the 2011 through 2013 tax years.
	(f) Recent Accounting Pronouncements
	In January 2014, FASB issued ASU No. 2014-04, Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. The amendments are intended to reduce diversity of practice by clarifying when a creditor should be considered to have received physical possession of residential real estate property collateralizing a residential mortgage loan, such that the loan should be removed, and the real estate property recognized, on the financial statements. Additionally, the amendments require interim and annual disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in collateralized residential mortgage loans that are in the process of foreclosure according to local requirements of the applicable jurisdiction. The amendments in this ASU are effective for public business entities for annual periods and interim reporting periods beginning after December 15, 2014. As this ASU primarily offers clarification of existing standards and added disclosures, the adoption of this ASU in the first quarter of 2015 is not expected to have a material impact on the Company's financial statements, or results of operations.
	In January 2014, the FASB issued ASU No. 2014-01, Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects. The amendments in this ASU apply to all reporting entities that invest in qualified affordable housing projects through limited liability entities that are flow through entities for tax purposes. The amendments in this ASU eliminate the effective yield election and permit reporting entities to make an accounting policy election to account for such investments using the proportional amortization method if certain conditions are met. Those not electing the proportional amortization method would account for the investment using the equity method or cost method. The decision to apply the proportional amortization method of accounting is an accounting policy decision that must be applied consistently to all qualifying affordable housing project investments rather than a decision to be applied to individual investments. The amendments in this ASU are to be applied retrospectively to all periods presented. The amendments in this ASU are effective for public business entities for annual periods and interim reporting periods beginning after December 15, 2014. Early adoption is permitted. The adoption by the Company of this ASU, on the effective date, is not expected to have a material impact on the Company's financial statements, or results of operations.

Investments

Investments	9 Months Ended
	Sep. 30, 2014
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:
			September 30, 2014
	(Dollars in thousands)		Amortized			Unrealized				Unrealized				Fair Value
			cost			gains				losses
	Federal agency obligations (1)		$	54,457		$	55			$	174			$	54,338
	Federal agency mortgage backed securities (MBS) (1)		91,875			613				945				91,543
	Municipal securities		66,544			2,201				52				68,693
	Corporate bonds		7,041			58				25				7,074
	Total fixed income securities		219,917			2,927				1,196				221,648
	Equity investments		11,543			3,568				6				15,105
	Total available for sale securities, at fair value		$	231,460		$	6,495			$	1,202			$	236,753
			December 31, 2013
	(Dollars in thousands)		Amortized			Unrealized				Unrealized				Fair Value
			cost			gains				losses
	Federal agency obligations(1)		$	55,440		$	146			$	43			$	55,543
	Federal agency mortgage backed securities (MBS) (1)		80,997			367				1,714				79,650
	Municipal securities		60,675			1,604				325				61,954
	Corporate bonds		5,080			29				55				5,054
	Total fixed income securities		202,192			2,146				2,137				202,201
	Equity investments		9,960			3,228				20				13,168
	Total available for sale securities, at fair value		$	212,152		$	5,374			$	2,157			$	215,369
	__________________________________________
	-1	These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae (FNMA), Freddie Mac (FHLMC), Ginnie Mae (GNMA), Federal Farm Credit Bank, or one of several Federal Home Loan Banks.  All agency MBS/Collateralized Mortgage Obligations ("CMOs") investments owned by the Company are backed by residential mortgages.
	Included in the carrying amount of the federal agency MBS category were CMOs totaling $14.3 million and $17.4 million at September 30, 2014 and December 31, 2013, respectively.
	At September 30, 2014, the equity portfolio consisted primarily of investments in a diversified group of mutual funds, with a small 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 nine months ended September 30, 2014 and 2013, the Company did not record any fair value impairment charges on its investments. As of September 30, 2014, there were a total of 55 investments (fixed income and equity), with a fair market value of $78.0 million, in an unrealized loss position totaling $1.2 million, including unrealized losses of $950 thousand that have been temporarily impaired for 12 months or longer. Management attributes these unrealized losses to increases in current market yields compared to the yields at the time the investments were purchased by the Company. Management does not consider these investments to be other-than-temporarily impaired at September 30, 2014, 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 federal agency MBS investments and federal agency obligations, the contractual cash flows of these investments are guaranteed by an agency of the U.S. Government, and the agency that issued these securities is sponsored by the U.S. Government. 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 investment's materiality, and duration of the 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. At September 30, 2014, 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.
	The contractual maturity distribution at September 30, 2014 of total fixed income investments is as follows:
		Within One Year						After One, But Within							After Five, But Within				After Ten Years
								Five Years							Ten Years
		Amortized			Yields			Amortized				Yields			Amortized		Yields		Amortized		Yields
		Cost						Cost							Cost				Cost
	At amortized cost:
	Federal agency obligations	$	5,003		0.59	%		$	28,011			1.37	%		$	21,443	1.95	%	$	—	—	%
	MBS	4			1.29	%		2,423				2.49	%		5,896		2.98	%	83,552		2.16	%
	Municipal securities	4,670			2.05	%		24,538				3.3	%		26,664		4.24	%	10,672		4.73	%
	Corporate bonds	100			1.26	%		4,287				1.6	%		2,654		3.02	%	—		—	%
	Total fixed income securities	$	9,777		1.29	%		$	59,259			2.23	%		$	56,657	3.18	%	$	94,224	2.45	%
	At fair value:
	Total fixed income securities	$	9,811					$	60,186						$	57,654			$	93,997
	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, federal agency obligations and corporate bonds totaling $36.1 million, which can be redeemed by the issuer prior to the maturity presented above.  Management considers these early payment 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 against 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 $221.6 million at September 30, 2014.
	See Note 8, “Fair Value Measurements” below for further information regarding the Company’s fair value measurements for available-for-sale securities.

Loans

Loans	9 Months Ended
	Sep. 30, 2014
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 are as follows:
	(Dollars in thousands)		September 30,				December 31,
			2014				2013
	Commercial real estate		$	843,648			$	820,299
	Commercial and industrial		396,990				357,056
	Commercial construction		142,352				132,507
	Total commercial loans		1,382,990				1,309,862
	Residential mortgages		143,825				132,721
	Home equity loans and lines		77,983				74,354
	Consumer		9,654				8,643
	Total retail loans		231,462				215,718
	Gross loans		1,614,452				1,525,580
	Deferred loan origination fees, net		(1,678		)		(1,524		)
	Total loans		1,612,774				1,524,056
	Allowance for loan losses		(27,029		)		(26,967		)
	Net loans		$	1,585,745			$	1,497,089
	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 property 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 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"), loans under various programs issued in conjunction with the Massachusetts Development Finance Agency and other agencies.  Commercial and industrial credits may be unsecured loans and lines to financially strong borrowers, 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 the underlying real estate collateral and are generally guaranteed by the principals of the borrowers.  Construction lenders work to cultivate long-term relationships with established 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, either by experienced construction lenders on staff or by independent outside inspection companies, at each construction phase, prior to advancing additional funds.  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.  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 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 the 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 the participating institution amounted to $51.7 million at September 30, 2014 and $34.5 million at December 31, 2013.
	Standby letters of credit are conditional commitments issued by the Company to guarantee the financial obligation or performance by 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, vacation homes, or investment properties.  Loan to value limits vary, generally from 80% for adjustable rate and multi-family, owner occupied properties, up to 97% for fixed rate loans on 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 primarily consist 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 September 30, 2014 and December 31, 2013, the Company was servicing residential mortgage loans owned by investors amounting to $19.2 million and $20.6 million, respectively.  Additionally, the Company was servicing commercial loans participated out to various other institutions amounting to $41.4 million and $52.1 million at September 30, 2014 and December 31, 2013, 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)	September 30,				December 31,
		2014				2013
	Commercial real estate	$	289,394			$	320,908
	Residential mortgages	106,941				97,626
	Home equity	16,630				17,548
	Total loans pledged to FHLB	$	412,965			$	436,082

Allowance_For_Loan_Loss

Allowance For Loan Loss	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Allowance for Credit Losses	'
	Allowance for Loan Loss
	While the Company manages 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.
	Allowance for probable loan losses methodology
	On a quarterly basis, management prepares an estimate of the allowance necessary to cover estimated credit losses.  The Company maintains the allowance at a level that it deems adequate to absorb all reasonably anticipated losses from specifically known and other credit risks associated with the portfolio.  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. 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 geographic market area and the strength of the local and national economy, among other factors.
	There have been no material changes in 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 Company’s most recent 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 Company’s 2013 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 September 30, 2014 by segment and evaluation method are summarized as follows:
	(Dollars in thousands)	Loans individually			Loans collectively				Total Loans
		evaluated for			evaluated for
		impairment			impairment
	Commercial real estate	$	13,940		$	829,708			$	843,648
	Commercial and industrial	10,877			386,113				396,990
	Commercial construction	2,900			139,452				142,352
	Residential	1,625			142,200				143,825
	Home equity	205			77,778				77,983
	Consumer	22			9,632				9,654
	Deferred Fees	—			(1,678		)		(1,678		)
	Total loans	$	29,569		$	1,583,205			$	1,612,774
	The balances of loans as of December 31, 2013 by segment and evaluation method are summarized as follows:
	(Dollars in thousands)	Loans individually			Loans collectively				Total Loans
		evaluated for			evaluated for
		impairment			impairment
	Commercial real estate	$	15,139		$	805,160			$	820,299
	Commercial and industrial	10,579			346,477				357,056
	Commercial construction	3,358			129,149				132,507
	Residential	619			132,102				132,721
	Home equity	108			74,246				74,354
	Consumer	23			8,620				8,643
	Deferred Fees	—			(1,524		)		(1,524		)
	Total loans	$	29,826		$	1,494,230			$	1,524,056
	Credit Quality Indicators
	The level of adversely classified loans and delinquent and non-performing assets is largely a function of economic conditions, the overall banking environment, the Company's underwriting, and credit risk management standards. The Company’s commercial lending focus may entail significant additional risks compared to long term financing on existing, owner-occupied residential real estate.  The Company endeavors to minimize this risk through sound underwriting practices and the risk management function. The credit risk management function focuses on a wide variety of factors, including, among others, current and expected economic conditions, the real estate market, the financial condition of borrowers, the ability of borrowers to adapt to changing conditions or circumstances affecting their business and the continuity of borrowers’ management teams.  Early detection of credit issues is critical to minimize credit losses. Accordingly, management regularly monitors these factors, among others, through ongoing credit reviews by the Credit Department, an external loan review service, reviews by members of senior management and the Loan Committee of the Board of Directors. This review includes the assessment of 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.
	The loan portfolio has experienced a level of modest credit stabilization compared to the 2013 periods, as indicated by the improving statistics related to adversely classified, non-accrual, and impaired loans, and the low number and level of Other Real Estate Owned ("OREO") properties held as of September 30, 2014. Given the size and commercial mix of the Company's loan portfolio, management considers the current statistics to be reflective of the lagging effect that the regional economic environment has had on the local commercial markets and its impact on the credit profile of such a portfolio.
	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, to 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 guaranties; 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 on 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.
		September 30, 2014
		Adversely Classified										Not Adversely
	(Dollars in thousands)	Substandard			Doubtful				Loss			Classified			Gross Loans
	Commercial real estate	$	9,865		$	1,207			$	30		$	832,546		$	843,648
	Commercial and industrial	11,242			49				90			385,609			396,990
	Commercial construction	2,983			—				—			139,369			142,352
	Residential	2,050			—				—			141,775			143,825
	Home equity	495			—				—			77,488			77,983
	Consumer	40			—				—			9,614			9,654
	Total gross loans	$	26,675		$	1,256			$	120		$	1,586,401		$	1,614,452
		December 31, 2013
		Adversely Classified										Not Adversely
	(Dollars in thousands)	Substandard			Doubtful				Loss			Classified			Gross Loans
	Commercial real estate	$	13,545		$	1,266			$	—		$	805,488		$	820,299
	Commercial and industrial	7,908			51				236			348,861			357,056
	Commercial construction	3,358			—				—			129,149			132,507
	Residential	1,012			—				—			131,709			132,721
	Home equity	500			—				—			73,854			74,354
	Consumer	40			—				—			8,603			8,643
	Total gross loans	$	26,363		$	1,317			$	236		$	1,497,664		$	1,525,580
	The minor shift in adversely classified loan balances amongst the categories since the prior period was due to a variety of activity including: credit rating upgrades, primarily in commercial real estate; payoffs; the foreclosure sale of underlying collateral with payoff on a larger commercial real estate relationship; and charge-offs, primarily commercial real estate and commercial and industrial loans; partially offset by additional credit downgrades, particularly in commercial and industrial and residential mortgage loans during the period.
	Past Due and Non-Accrual Loans
	Loans on which the accrual of interest has been discontinued are designated as non-accrual loans.  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 numbers below.
	The following tables present age analysis of past due loans as of the dates indicated.
Balance at September 30, 2014
(Dollars in thousands)	Loans			Loans				Loans 90 or			Total Past			Current Loans			Gross
	30-59 Days			60-89 Days				More Days			Due Loans						Loans
	Past Due			Past Due				Past Due (non-
								accrual)
Commercial real estate	$	4,265		$	2,902			$	8,028		$	15,195		$	828,453		$	843,648
Commercial and industrial	1,638			540				5,865			8,043			388,947			396,990
Commercial construction	3,833			68				669			4,570			137,782			142,352
Residential	537			685				1,677			2,899			140,926			143,825
Home equity	29			—				276			305			77,678			77,983
Consumer	18			13				25			56			9,598			9,654
Total gross loans	$	10,320		$	4,208			$	16,540		$	31,068		$	1,583,384		$	1,614,452
Balance at December 31, 2013
(Dollars in thousands)	Loans			Loans				Loans 90 or			Total Past			Current Loans			Gross Loans
	30-59 Days			60-89 Days				More Days			Due Loans
	Past Due			Past Due				Past Due (non-
								accrual)
Commercial real estate	$	1,142		$	1,575			$	10,561		$	13,278		$	807,021		$	820,299
Commercial and industrial	680			908				5,743			7,331			349,725			357,056
Commercial construction	196			—				1,118			1,314			131,193			132,507
Residential	1,110			127				633			1,870			130,851			132,721
Home equity	211			10				281			502			73,852			74,354
Consumer	106			18				10			134			8,509			8,643
Total gross loans	$	3,445		$	2,638			$	18,346		$	24,429		$	1,501,151		$	1,525,580
At September 30, 2014 and December 31, 2013, all loans 90 days or more past due were carried as non-accrual. Included in the consumer non-accrual numbers in the table above were $16 thousand and $3 thousand of overdraft deposit account balances 90 days or more past due at September 30, 2014 and December 31, 2013, respectively. Total non-performing loans amounted to $16.5 million and $18.3 million at September 30, 2014 and December 31, 2013, respectively. Non-accrual loans which were not adversely classified amounted to $229 thousand at September 30, 2014 and $577 thousand at December 31, 2013. 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 increase in loans 30-59 days past due occurred within the commercial portfolios at September 30, 2014, with the majority of these loans having subsequent payments made by mid-October.
The ratio of non-accrual loans to total loans amounted to 1.03% at September 30, 2014, 1.20% at December 31, 2013, and 1.35% at September 30, 2013.
At September 30, 2014, additional funding commitments for loans on non-accrual status totaled $100 thousand. 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.
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.  Impaired loans may be included within the non-accrual balances; however, not every loan in non-accrual status has been designated as impaired.  Impaired loans include troubled debt restructured ("TDR") loans.  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 expectation of the borrower's ability to continue to service the loan in accordance the original or modified terms and the collectability of the remaining balance, and in the case of TDR loans, an interest rate at, or greater than, a market rate for a similar credit at the time of modification is assessed.
Impaired loans are individually evaluated for credit loss and a specific allowance reserve is assigned for the amount of the estimated 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 Company’s 2013 Annual Report on Form 10-K for further discussion of management’s methodology used to estimate specific reserves for impaired loans.
Total impaired loans amounted to $29.6 million and $29.8 million, at September 30, 2014 and December 31, 2013, respectively.  Total accruing impaired loans amounted to $13.5 million and $11.9 million at September 30, 2014 and December 31, 2013, respectively, while non-accrual impaired loans amounted to $16.1 million and $17.9 million as of September 30, 2014 and December 31, 2013, respectively.
The following tables set forth the recorded investment in impaired loans and the related specific allowance allocated as of the dated indicated.
Balance at September 30, 2014
(Dollars in thousands)	Unpaid			Total recorded				Recorded			Recorded			Related specific
	contractual			investment in				investment			investment			allowance
	principal balance			impaired loans				with no			with
								allowance			allowance
Commercial real estate	$	16,040		$	13,940			$	13,306		$	634		$	110
Commercial and industrial	11,986			10,877				4,046			6,831			2,198
Commercial construction	3,125			2,900				1,082			1,818			690
Residential	1,699			1,625				1,375			250			103
Home equity	208			205				—			205			46
Consumer	22			22				—			22			22
Total	$	33,080		$	29,569			$	19,809		$	9,760		$	3,169
Balance at December 31, 2013
(Dollars in thousands)	Unpaid			Total recorded				Recorded			Recorded			Related specific
	contractual			investment in				investment			investment			allowance
	principal balance			impaired loans				with no			with
								allowance			allowance
Commercial real estate	$	17,420		$	15,139			$	12,105		$	3,034		$	507
Commercial and industrial	12,220			10,579				4,902			5,677			2,901
Commercial construction	3,464			3,358				1,426			1,932			830
Residential	673			619				365			254			107
Home equity	110			108				—			108			31
Consumer	23			23				—			23			23
Total	$	33,910		$	29,826			$	18,798		$	11,028		$	4,399
The reduction in related specific reserves on impaired loans was due primarily to increases in estimated current realizable collateral values and current charge-offs of previously allocated specific reserves on commercial relationships for which management deemed collectability of amounts due was unlikely based on current realizable collateral values, partially offset by additional reserves for newly impaired loans during the period.
The following table presents the average recorded investment in impaired loans and the related interest recognized during the three month periods indicated.
	Three Months Ended September 30, 2014							Three Months Ended September 30, 2013
(Dollars in thousands)	Average recorded			Interest income				Average recorded			Interest income
	investment			recognized				investment			recognized
Commercial real estate	$	14,224		$	75			$	15,405		$	42
Commercial and industrial	10,279			40				9,081			23
Commercial construction	3,174			27				3,540			17
Residential	1,294			(2		)		741			3
Home equity	243			(1		)		109			—
Consumer	25			1				18			1
Total	$	29,239		$	140			$	28,894		$	86
The following table presents the average recorded investment in impaired loans and the related interest recognized during the nine month periods indicated.
	Nine Months Ended September 30, 2014							Nine Months Ended September 30, 2013
(Dollars in thousands)	Average recorded			Interest income				Average recorded			Interest income
	investment			recognized				investment			recognized
Commercial real estate	$	13,913		$	169			$	18,572		$	191
Commercial and industrial	10,482			120				9,312			77
Commercial construction	3,243			79				3,114			50
Residential	1,032			1				785			7
Home equity	215			(1		)		119			—
Consumer	25			1				17			1
Total	$	28,910		$	369			$	31,919		$	326
At September 30, 2014, additional funding commitments for impaired loans totaled $167 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 Restructures
Loans are designated as a TDR when, as part of an agreement to modify the original contractual terms of the loan, the Bank grants the borrower a concession on the terms, that would not otherwise be considered, as a result of financial difficulties of the borrower.  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 credit loss.
Total TDR loans, included in the impaired loan figures above, as of September 30, 2014 and December 31, 2013, were $20.7 million and $20.9 million, respectively. TDR loans on accrual status amounted to $13.0 million and $11.4 million at September 30, 2014 and December 31, 2013, respectively. TDR loans included in non-performing loans amounted to $7.7 million and $9.5 million at September 30, 2014 and December 31, 2013, 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 September 30, 2014, additional funding commitments for TDR loans totaled $75 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.
Loans modified as trouble debt restructurings during the three month period ended September 30, 2014 are detailed below.
	Three months ended September 30, 2014
(Dollars in thousands)	Number of		Pre-modification				Post-modification
	restructurings		outstanding recorded				outstanding recorded
			investment				investment
Commercial real estate	2		$	1,429			$	1,429
Commercial and industrial	2		43				43
Commercial construction	—		—				—
Residential	—		—				—
Home equity	—		—				—
Consumer	—		—				—
Total	4		$	1,472			$	1,472
Loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the periods noted are detailed below.
	Three months ended September 30, 2014
(Dollars in thousands)	Number of TDRs that defaulted		Post-
			modification outstanding
			recorded investment
Commercial real estate	—		$	—
Commercial and industrial	—		—
Commercial construction	—		—
Residential	1		126
Home Equity	—		—
Consumer	—		—
Total	1		$	126
Loans modified as troubled debt restructurings during the nine month period ended September 30, 2014 are detailed below.
	Nine months ended September 30, 2014
(Dollars in thousands)	Number of		Pre-modification				Post-modification
	restructurings		outstanding recorded				outstanding recorded
			investment				investment
Commercial real estate	3		$	1,979			$	1,979
Commercial and industrial	8		268				263
Commercial construction	—		—				—
Residential	1		124				122
Home equity	1		73				73
Consumer	—		—				—
Total	13		$	2,444			$	2,437
Loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the period noted are detailed below.
	Nine months ended September 30, 2014
(Dollars in thousands)	Number of TDRs that defaulted		Post-
			modification outstanding
			recorded investment
Commercial real estate	—		$	—
Commercial and industrial	1		66
Commercial construction	—		—
Residential	1		126
Home Equity	—		—
Consumer	—		—
Total	2		$	192
At September 30, 2014, there were specific reserves of $45 thousand allocated to the TDRs entered into during the 2014 period as management considered it likely the majority of 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 nine months ended September 30, 2014 amounted to $5 thousand.
There were subsequent charge-offs of $66 thousand associated with the TDRs noted in the table above during the nine months ended September 30, 2014.
Loans modified as troubled debt restructurings during the three month period ended September 30, 2013 are detailed below.
	Three months ended September 30, 2013
(Dollars in thousands)	Number of		Pre-modification				Post-modification
	restructurings		outstanding recorded				outstanding recorded
			investment				investment
Commercial real estate	1		$	342			$	291
Commercial and industrial	1		89				42
Commercial construction	1		769				769
Residential	—		—				—
Home equity	—		—				—
Consumer	—		—				—
Total	3		$	1,200			$	1,102
There were no loans modified as troubled debt restructurings within the twelve month period previous to September 30, 2013 for which there was a subsequent payment default during the three months ended September 30, 2013.
Loans modified as troubled debt restructurings during the nine month period ended September 30, 2013 are detailed below.
	Nine months ended September 30, 2013
(Dollars in thousands)	Number of		Pre-modification				Post-modification
	restructurings		outstanding recorded				outstanding recorded
			investment				investment
Commercial real estate	1		$	342			$	291
Commercial and industrial	2		189				104
Commercial construction	1		769				769
Residential	—		—				—
Home equity	—		—				—
Consumer	—		—				—
Total	4		$	1,300			$	1,164
Loans modified as troubled debt restructuring within the twelve month period previous to September 30, 2013 for which there was a subsequent payment default during the period noted are detailed below.
	Nine months ended September 30, 2013
(Dollars in thousands)	Number of TDRs that defaulted		Post-
			modification outstanding
			recorded investment
Commercial real estate	1		$	137
Commercial and industrial	1		62
Commercial construction	1		31
Residential	—		—
Home Equity	—		—
Consumer	—		—
Total	3		$	230
There were subsequent charge-offs of $38 thousand associated with the TDRs noted in the table above during the nine months ended September 30, 2013.  Included in the table above were two TDRs which defaulted, with total post modification outstanding balances of $168 thousand, and were subsequently transferred to OREO during the September 30, 2013 period. At September 30, 2013, specific reserves allocated to the TDRs entered into during the 2013 period amounted to $80 thousand, as management considered it likely that the majority of principal would ultimately be collected.
Other Real Estate Owned
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. 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 carrying value of OREO at September 30, 2014 was $861 thousand and consisted of three properties; and as of December 31, 2013 was $114 thousand and consisted of one property. During the nine months ended September 30, 2014, two properties were added to OREO. There were no sales or subsequent write-down of OREO during the nine months ended September 30, 2014. There were $121 thousand of gains realized on OREO sales during the nine months ended September 30, 2013 and a subsequent write-down of $23 thousand was recorded 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 $27.0 million at both September 30, 2014 and December 31, 2013 compared to $26.0 million at September 30, 2013. The allowance for loan losses to total loans ratio was 1.68% at September 30, 2014 compared to 1.77% at both December 31, 2013 and September 30, 2013. The decline in the overall allowance to total loan ratio at September 30, 2014 primarily resulted from the increase in the outstanding loan balances and a reduction in specific reserves. Specific reserves declined due to current charge-offs, the majority of which were previously allocated specific reserves on commercial relationships for which management deemed collectability of amounts due was unlikely based on current realizable collateral values, partially offset by additional reserves for newly impaired loans during the period.
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 September 30, 2014.
Changes in the allowance for loan losses by segment for the three months ended September 30, 2014, are presented below:
(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
	Estate			Industrial				Constr			Mortgage			Equity
Beginning Balance at June 30, 2014	$	13,065		$	7,550			$	3,741		$	1,266		$	685		$	221	$	26,528
Provision	154			664				(90		)	(38		)	36			39		765
Recoveries	—			286				17			—			1			2		306
Less: Charge offs	92			256				134			46			27			15		570
Ending Balance at September 30, 2014	$	13,127		$	8,244			$	3,534		$	1,182		$	695		$	247	$	27,029
Changes in the allowance for loan losses by segment for the nine months ended September 30, 2014, are presented below:
(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
	Estate			Industrial				Constr			Mortgage			Equity
Beginning Balance at December 31, 2013	$	13,174		$	8,365			$	3,493		$	1,057		$	653		$	225	$	26,967
Provision	248			512				128			171			68			38		1,165
Recoveries	—			510				47			—			1			24		582
Less: Charge offs	295			1,143				134			46			27			40		1,685
Ending Balance at September 30, 2014	$	13,127		$	8,244			$	3,534		$	1,182		$	695		$	247	$	27,029
Ending allowance balance:
Allotted to loans individually evaluated for impairment	$	110		$	2,198			$	690		$	103		$	46		$	22	$	3,169
Allotted to loans collectively evaluated for impairment	$	13,017		$	6,046			$	2,844		$	1,079		$	649		$	225	$	23,860
Changes in the allowance for loan losses by segment for the three months ended September 30, 2013, are presented below:
(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
	Estate			Industrial				Constr			Mortgage			Equity
Beginning Balance at June 30, 2013	$	13,020		$	7,633			$	3,154		$	1,033		$	682		$	149	$	25,671
Provision	162			422				28			(24		)	(34		)	29		583
Recoveries	34			15				—			—			—			3		52
Less: Charge offs	192			70				—			36			—			9		307
Balance at September 30, 2013	$	13,024		$	8,000			$	3,182		$	973		$	648		$	172	$	25,999
Changes in the allowance for loan losses by segment for the nine months ended September 30, 2013, are presented below:
(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
	Estate			Industrial				Constr			Mortgage			Equity
Beginning Balance at December 31, 2012	$	11,793		$	7,297			$	3,456		$	854		$	728		$	126	$	24,254
Provision	1,342			850				(324		)	27			(57		)	62		1,900
Recoveries	95			56				50			128			21			9		359
Less: Charge offs	206			203				—			36			44			25		514
Ending Balance at September 30, 2013	$	13,024		$	8,000			$	3,182		$	973		$	648		$	172	$	25,999
Ending allowance balance:
Allotted to loans individually evaluated for impairment	$	544		$	2,602			$	875		$	68		$	34		$	18	$	4,141
Allotted to loans collectively evaluated for impairment	$	12,480		$	5,398			$	2,307		$	905		$	614		$	154	$	21,858

Supplemental_Retirement_Plan_a

Supplemental Retirement Plan and Other Postretirement Benefit Obligations	9 Months Ended
	Sep. 30, 2014
Compensation and Retirement Disclosure [Abstract]	'
Supplemental Retirement Plan and Other Postretirement Benefit Obligations	'
	Supplemental Retirement Plan and Other Postretirement Benefit Obligations
	Supplemental Retirement Plan (SERPs)
	The Company has salary continuation agreements with two of its active executive officers, and one former executive officer who currently works on a part time basis. 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 Company has not recognized service cost 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 in exchange for the employee’s service rendered to that date.  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.
	The total net periodic benefit cost, which was comprised of interest cost only, was $36 thousand for the three months ended September 30, 2014, compared to $33 thousand for the three months ended September 30, 2013. Year-to-date total net periodic benefit cost, comprised of interest cost only, was $107 thousand for the nine months ended September 30, 2014, compared to $100 thousand for the nine months ended September 30, 2013.
	Benefits paid amounted to $69 thousand for both the three month periods ended September 30, 2014 and September 30, 2013 and $207 thousand for both the nine month periods ended September 30, 2014 and September 30, 2013. The Company anticipates accruing an additional $36 thousand to the plan during the remainder of 2014.
	Supplemental Life Insurance
	For certain senior and executive officers on whom the Bank owns bank owned life insurance ("BOLI"), the Company has provided supplemental life insurance through split-dollar life insurance arrangements, which provides a death benefit to the officer’s designated beneficiaries.
	The Company has recognized a liability for future benefits associated with the supplemental life insurance plan, which is a non-qualified plan, which provides a benefit to an employee that extends to postretirement periods. This 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 Postretirement Benefit Obligation,” which is the present value of the post- retirement benefits associated with this arrangement.
	The total net periodic benefit cost, which was comprised of interest cost only, amounted to $19 thousand and $55 thousand for the three and nine months ended September 30, 2014, respectively, compared to $18 thousand and $54 thousand for the three and nine months ended September 30, 2013, respectively.

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Stock-Based Compensation	'
	Stock-Based Compensation
	The Company has individual stock incentive plans and has not changed the general terms and conditions of these plans from those disclosed in the Company’s 2013 Annual Report on Form 10-K.
	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 directors included in other operating expenses.  Total stock-based compensation expense was $409 thousand and $1.3 million for the three and nine months ended September 30, 2014, respectively, compared to $380 thousand and $1.2 million for the three and nine months ended September 30, 2013, respectively.
	Stock Option Awards
	The Company recognized stock-based compensation expense related to stock option awards of $87 thousand and $277 thousand for the three and nine months ended September 30, 2014, respectively, compared to $75 thousand and $344 thousand for the three and nine months ended September 30, 2013, respectively.
	The table below provides a summary of the options granted, fair value, the fair value as a percentage of the market value of the stock at the date of grant and the average assumptions used in the model for the options granted in 2014 and 2013.
		Nine Months Ended September 30,
		2014			2013
	Options granted	31,229			44,475
	Term in years	10			10
	Average assumptions used in the model:
	Expected volatility	47		%	48		%
	Expected dividend yield	2.88		%	2.99		%
	Expected life in years	7			7
	Risk-free interest rate	2.19		%	1.3		%
	Market price on date of grant	$	20.29		$	16.46
	Per share weighted average fair value	$	8.32		$	6.58
	Fair value as a percentage of market value at grant date	41		%	40		%
	Options granted during the first nine months of 2014 and 2013 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.
	The Company utilizes the Black-Scholes option valuation model in order to determine the per share grant date fair value of option grants.
	Refer to Note 11 “Stock-Based Compensation Plans” in the Company’s 2013 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 $278 thousand and $868 thousand for the three and nine months ended September 30, 2014, respectively, compared to $265 thousand and $746 thousand for the three and nine months ended September 30, 2013, respectively.
	In January 2014, the Company granted 2,142 shares of fully vested stock to employees as anniversary awards at a grant date fair market value of $20.95 per share.
	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. Employee performance based awards vest upon the Company achieving certain predefined performance objectives. 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 2014 and 2013.
		Nine Months Ended September 30,
	Restricted Stock Awards	2014			2013
	Two Year Vesting	6,660			6,146
	Four Year Vesting	19,167			25,325
	Performance-Based Vesting	33,017			47,735
	Total Restricted Stock Awards	58,844			79,206
	Weighted average grant date fair value	$	20.29		$	16.45
	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.
	Stock in Lieu of Directors’ Fees
	In addition to restricted stock awards discussed above, the 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 directors’ election to receive shares of common stock in lieu of cash fees for meetings amounted to $44 thousand and $180 thousand for the three and nine months ended September 30, 2014, respectively, compared to $40 thousand and $149 thousand for the three and nine months ended September 30, 2013, respectively. In January 2014, directors were issued 11,136 shares of common stock in lieu of cash fees based on their 2013 annual stock-based compensation expense of $194 thousand and a market value price of $17.43 per share, the market value of the common stock on the opt-in measurement date of January 2, 2013.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings per share
	Basic earnings per share are calculated by dividing net income 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 September 30,		Nine months ended September 30,
		2014	2013	2014	2013
	Basic weighted average common shares outstanding	10,143,055	9,932,060	10,099,593	9,824,984
	Dilutive shares	85,446	94,528	84,671	84,035
	Diluted weighted average common shares outstanding	10,228,501	10,026,588	10,184,264	9,909,019
	For the nine months ended September 30, 2014, there were an additional 22,776 average stock options outstanding, which were excluded from the year-to-date calculation of diluted earnings per share due to the exercise price of these options exceeding the average market price of the Company’s common stock for the period.  These options, which were not dilutive at that date, may potentially dilute earnings per share in the future.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2014
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:
			September 30, 2014			Fair Value Measurements using:
	(Dollars in thousands)		Fair Value			(level 1)			(level 2)		(level 3)
	Assets measured on a recurring basis:
	Fixed income securities		$	221,648		$	—		$	221,648	$	—
	Equity securities		15,105			15,105			—		—
	FHLB Stock		3,357			—			—		3,357
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		5,790			—			—		5,790
	Other real estate owned		861			—			—		861
			December 31,			Fair Value Measurements using:
			2013
	(Dollars in thousands)		Fair Value			(level 1)			(level 2)		(level 3)
	Assets measured on a recurring basis:
	Fixed income securities		$	202,201		$	—		$	202,201	$	—
	Equity securities		13,168			13,168			—		—
	FHLB Stock		4,324			—			—		4,324
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		6,542			—			—		6,542
	Other real estate owned		114			—			—		114
	The Company did not have cause to transfer any assets between the fair value measurement levels during the nine months ended September 30, 2014 or the year ended December 31, 2013. There were no liabilities measured at fair value on a recurring or non-recurring basis as of September 30, 2014 or December 31, 2013.
	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, federal agency MBS, municipal securities and corporate bonds 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.
	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 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 credit loss.  The specific allowances assigned to the collateral dependent impaired loans at September 30, 2014 amounted to $2.4 million compared to $3.2 million at December 31, 2013.
	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 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. There were no sales of OREO during the nine months ended September 30, 2014. There were $121 thousand of gains realized on OREO sales during the nine months ended September 30, 2013 and a subsequent write-down of $23 thousand was recorded during that period.
	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 September 30, 2014.
	(Dollars in thousands)		Fair Value		Valuation Technique	Unobservable Input		Unobservable Input Value or Range
	Assets measured on a recurring basis:
	FHLB Stock		$3,357		FHLB Stated Par Value	N/A		N/A
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		$5,790		Appraisal of collateral	Appraisal adjustments (1)		5% - 50%
	Other real estate owned		$861		Appraisal of collateral	Appraisal adjustments (1)		0% - 30%
	-1	Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses.
	Other Guarantees and Commitments
	Standby letters of credit are conditional commitments issued by the Company to guarantee the financial obligation or performance by 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 September 30, 2014 and December 31, 2013 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 represent the Company’s only derivative instruments and 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 September 30, 2014 and December 31, 2013, the estimated fair value of the Company’s derivative instruments was considered to be immaterial.
	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.  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.
	Commitments: The fair values of the unused portion of lines of credit and letters of credit were estimated to be the fees currently charged to enter into similar agreements.  Commitments to originate non-mortgage loans were short-term and were at current market rates and estimated to have no significant change in 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 September 30, 2014 and December 31, 2013 for similar instruments.  The fair value of junior subordinated debentures was estimated using discounted cash flow analysis using a market rate of interest at September 30, 2014 and December 31, 2013.
	Limitations:  The estimates of fair value of financial instruments were based on information available at September 30, 2014 and December 31, 2013 and are not indicative of the fair market value of those instruments as of the date of this report.  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.
	The carrying values, estimated fair values and placement in the fair value hierarchy of the Company’s financial instruments(1) for which fair value is only disclosed but not recognized on the balance sheet at the dates indicated are summarized as follows:
			September 30, 2014						Fair value measurement
	(Dollars in thousands)		Carrying			Fair Value			Level 1 inputs		Level 2 Inputs		Level 3 Inputs
			Amount
	Financial assets:
	Loans held for sale		$	1,645		$	1,645		$	—	$	1,645	—
	Loans, net		1,585,745			1,606,731			—		—		1,606,731
	Financial liabilities:
	Certificates of deposit (including brokered)		271,298			269,999			—		269,999		—
	Borrowed funds		1,004			1,004			—		1,004		—
	Junior subordinated debentures		10,825			12,629			—		—		12,629
			December 31, 2013						Fair value measurement
	(Dollars in thousands)		Carrying			Fair Value			Level 1 inputs		Level 2 Inputs		Level 3 Inputs
Amount
Financial assets:
Loans held for sale		$	1,255		$	1,255		$	—	$	1,255	—
Loans, net		1,497,089			1,516,809			—		—		1,516,809
Financial liabilities:
Certificates of deposit (including brokered)		251,650			250,045			—		250,045		—
Borrowed funds		36,534			36,535			—		36,535		—
Junior subordinated debentures		10,825			11,358			—		—		11,358
-1	Excluded from this table 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.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
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, 2013 audited consolidated financial statements and notes thereto contained in the 2013 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 14, 2014.  The Company has not changed its reporting policies from those disclosed in its 2013 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.
	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, which hold various types of qualifying securities.  The security corporations 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 Merrimack Valley and North Central regions of Massachusetts and Southern New Hampshire. Through the Bank and its subsidiaries, the Company offers a range of commercial and consumer loan products, deposit and cash management products, 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.
	Pursuant to the Accounting Standards Codification (“ASC”) Topic 810 “Consolidation of Variable Interest Entities,” issued by the Financial Accounting Standards Board (“FASB”), the Company carries Junior Subordinated Debentures as a liability on its consolidated interim 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, are excluded from the Company’s consolidated interim financial statements.
	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.
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 estimates and assumptions 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 2013 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 2013 Annual Report on Form 10-K for significant accounting policies. The Company has not changed its significant accounting policies from those disclosed in its 2013 Annual Report filed on Form 10-K.
Reporting Comprehensive Income	'
	Reporting Comprehensive Income
	Comprehensive income is defined as all changes to 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 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 ongoing 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, primarily due 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 September 30, 2014.  The Company is subject to U.S. federal and state income tax examinations by taxing authorities for the 2011 through 2013 tax years.
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In January 2014, FASB issued ASU No. 2014-04, Receivables - Troubled Debt Restructurings by Creditors (Subtopic 310-40) - Reclassification of Residential Real Estate Collateralized Consumer Mortgage Loans upon Foreclosure. The amendments are intended to reduce diversity of practice by clarifying when a creditor should be considered to have received physical possession of residential real estate property collateralizing a residential mortgage loan, such that the loan should be removed, and the real estate property recognized, on the financial statements. Additionally, the amendments require interim and annual disclosure of both the amount of foreclosed residential real estate property held by the creditor and the recorded investment in collateralized residential mortgage loans that are in the process of foreclosure according to local requirements of the applicable jurisdiction. The amendments in this ASU are effective for public business entities for annual periods and interim reporting periods beginning after December 15, 2014. As this ASU primarily offers clarification of existing standards and added disclosures, the adoption of this ASU in the first quarter of 2015 is not expected to have a material impact on the Company's financial statements, or results of operations.
	In January 2014, the FASB issued ASU No. 2014-01, Equity Method and Joint Ventures (Topic 323): Accounting for Investments in Qualified Affordable Housing Projects. The amendments in this ASU apply to all reporting entities that invest in qualified affordable housing projects through limited liability entities that are flow through entities for tax purposes. The amendments in this ASU eliminate the effective yield election and permit reporting entities to make an accounting policy election to account for such investments using the proportional amortization method if certain conditions are met. Those not electing the proportional amortization method would account for the investment using the equity method or cost method. The decision to apply the proportional amortization method of accounting is an accounting policy decision that must be applied consistently to all qualifying affordable housing project investments rather than a decision to be applied to individual investments. The amendments in this ASU are to be applied retrospectively to all periods presented. The amendments in this ASU are effective for public business entities for annual periods and interim reporting periods beginning after December 15, 2014. Early adoption is permitted. The adoption by the Company of this ASU, on the effective date, is not expected to have a material impact on the Company's financial statements, or results of operations.

Investments_Tables

Investments (Tables)	9 Months Ended
	Sep. 30, 2014
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:
			September 30, 2014
	(Dollars in thousands)		Amortized			Unrealized				Unrealized				Fair Value
			cost			gains				losses
	Federal agency obligations (1)		$	54,457		$	55			$	174			$	54,338
	Federal agency mortgage backed securities (MBS) (1)		91,875			613				945				91,543
	Municipal securities		66,544			2,201				52				68,693
	Corporate bonds		7,041			58				25				7,074
	Total fixed income securities		219,917			2,927				1,196				221,648
	Equity investments		11,543			3,568				6				15,105
	Total available for sale securities, at fair value		$	231,460		$	6,495			$	1,202			$	236,753
			December 31, 2013
	(Dollars in thousands)		Amortized			Unrealized				Unrealized				Fair Value
			cost			gains				losses
	Federal agency obligations(1)		$	55,440		$	146			$	43			$	55,543
	Federal agency mortgage backed securities (MBS) (1)		80,997			367				1,714				79,650
	Municipal securities		60,675			1,604				325				61,954
	Corporate bonds		5,080			29				55				5,054
	Total fixed income securities		202,192			2,146				2,137				202,201
	Equity investments		9,960			3,228				20				13,168
	Total available for sale securities, at fair value		$	212,152		$	5,374			$	2,157			$	215,369
	__________________________________________
	-1	These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae (FNMA), Freddie Mac (FHLMC), Ginnie Mae (GNMA), Federal Farm Credit Bank, or one of several Federal Home Loan Banks.  All agency MBS/Collateralized Mortgage Obligations ("CMOs") investments owned by the Company are backed by residential mortgages.
Investments Classified by Contractual Maturity Date	'
	The contractual maturity distribution at September 30, 2014 of total fixed income investments is as follows:
		Within One Year						After One, But Within							After Five, But Within				After Ten Years
								Five Years							Ten Years
		Amortized			Yields			Amortized				Yields			Amortized		Yields		Amortized		Yields
		Cost						Cost							Cost				Cost
	At amortized cost:
	Federal agency obligations	$	5,003		0.59	%		$	28,011			1.37	%		$	21,443	1.95	%	$	—	—	%
	MBS	4			1.29	%		2,423				2.49	%		5,896		2.98	%	83,552		2.16	%
	Municipal securities	4,670			2.05	%		24,538				3.3	%		26,664		4.24	%	10,672		4.73	%
	Corporate bonds	100			1.26	%		4,287				1.6	%		2,654		3.02	%	—		—	%
	Total fixed income securities	$	9,777		1.29	%		$	59,259			2.23	%		$	56,657	3.18	%	$	94,224	2.45	%
	At fair value:
	Total fixed income securities	$	9,811					$	60,186						$	57,654			$	93,997

Loans_Tables

Loans (Tables)	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Schedule of Loans by Loan Classification	'
	Major classifications of loans at the periods indicated are as follows:
	(Dollars in thousands)		September 30,				December 31,
			2014				2013
	Commercial real estate		$	843,648			$	820,299
	Commercial and industrial		396,990				357,056
	Commercial construction		142,352				132,507
	Total commercial loans		1,382,990				1,309,862
	Residential mortgages		143,825				132,721
	Home equity loans and lines		77,983				74,354
	Consumer		9,654				8,643
	Total retail loans		231,462				215,718
	Gross loans		1,614,452				1,525,580
	Deferred loan origination fees, net		(1,678		)		(1,524		)
	Total loans		1,612,774				1,524,056
	Allowance for loan losses		(27,029		)		(26,967		)
	Net loans		$	1,585,745			$	1,497,089
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)	September 30,				December 31,
		2014				2013
	Commercial real estate	$	289,394			$	320,908
	Residential mortgages	106,941				97,626
	Home equity	16,630				17,548
	Total loans pledged to FHLB	$	412,965			$	436,082

Allowance_For_Loan_Loss_Tables

Allowance For Loan Loss (Tables)	9 Months Ended
	Sep. 30, 2014
Receivables [Abstract]	'
Financing Receivables by Evaluation Method	'
	The balances of loans as of September 30, 2014 by segment and evaluation method are summarized as follows:
	(Dollars in thousands)	Loans individually			Loans collectively				Total Loans
		evaluated for			evaluated for
		impairment			impairment
	Commercial real estate	$	13,940		$	829,708			$	843,648
	Commercial and industrial	10,877			386,113				396,990
	Commercial construction	2,900			139,452				142,352
	Residential	1,625			142,200				143,825
	Home equity	205			77,778				77,983
	Consumer	22			9,632				9,654
	Deferred Fees	—			(1,678		)		(1,678		)
	Total loans	$	29,569		$	1,583,205			$	1,612,774
	The balances of loans as of December 31, 2013 by segment and evaluation method are summarized as follows:
	(Dollars in thousands)	Loans individually			Loans collectively				Total Loans
		evaluated for			evaluated for
		impairment			impairment
	Commercial real estate	$	15,139		$	805,160			$	820,299
	Commercial and industrial	10,579			346,477				357,056
	Commercial construction	3,358			129,149				132,507
	Residential	619			132,102				132,721
	Home equity	108			74,246				74,354
	Consumer	23			8,620				8,643
	Deferred Fees	—			(1,524		)		(1,524		)
	Total loans	$	29,826		$	1,494,230			$	1,524,056
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.
		September 30, 2014
		Adversely Classified										Not Adversely
	(Dollars in thousands)	Substandard			Doubtful				Loss			Classified			Gross Loans
	Commercial real estate	$	9,865		$	1,207			$	30		$	832,546		$	843,648
	Commercial and industrial	11,242			49				90			385,609			396,990
	Commercial construction	2,983			—				—			139,369			142,352
	Residential	2,050			—				—			141,775			143,825
	Home equity	495			—				—			77,488			77,983
	Consumer	40			—				—			9,614			9,654
	Total gross loans	$	26,675		$	1,256			$	120		$	1,586,401		$	1,614,452
		December 31, 2013
		Adversely Classified										Not Adversely
	(Dollars in thousands)	Substandard			Doubtful				Loss			Classified			Gross Loans
	Commercial real estate	$	13,545		$	1,266			$	—		$	805,488		$	820,299
	Commercial and industrial	7,908			51				236			348,861			357,056
	Commercial construction	3,358			—				—			129,149			132,507
	Residential	1,012			—				—			131,709			132,721
	Home equity	500			—				—			73,854			74,354
	Consumer	40			—				—			8,603			8,643
	Total gross loans	$	26,363		$	1,317			$	236		$	1,497,664		$	1,525,580
Past Due Financing Receivables	'
	The following tables present age analysis of past due loans as of the dates indicated.
	Balance at September 30, 2014
	(Dollars in thousands)	Loans			Loans				Loans 90 or			Total Past			Current Loans			Gross
		30-59 Days			60-89 Days				More Days			Due Loans						Loans
		Past Due			Past Due				Past Due (non-
									accrual)
	Commercial real estate	$	4,265		$	2,902			$	8,028		$	15,195		$	828,453		$	843,648
	Commercial and industrial	1,638			540				5,865			8,043			388,947			396,990
	Commercial construction	3,833			68				669			4,570			137,782			142,352
	Residential	537			685				1,677			2,899			140,926			143,825
	Home equity	29			—				276			305			77,678			77,983
	Consumer	18			13				25			56			9,598			9,654
	Total gross loans	$	10,320		$	4,208			$	16,540		$	31,068		$	1,583,384		$	1,614,452
	Balance at December 31, 2013
	(Dollars in thousands)	Loans			Loans				Loans 90 or			Total Past			Current Loans			Gross Loans
		30-59 Days			60-89 Days				More Days			Due Loans
		Past Due			Past Due				Past Due (non-
									accrual)
	Commercial real estate	$	1,142		$	1,575			$	10,561		$	13,278		$	807,021		$	820,299
	Commercial and industrial	680			908				5,743			7,331			349,725			357,056
	Commercial construction	196			—				1,118			1,314			131,193			132,507
	Residential	1,110			127				633			1,870			130,851			132,721
	Home equity	211			10				281			502			73,852			74,354
	Consumer	106			18				10			134			8,509			8,643
	Total gross loans	$	3,445		$	2,638			$	18,346		$	24,429		$	1,501,151		$	1,525,580
Impaired Financing Receivables	'
	The following tables set forth the recorded investment in impaired loans and the related specific allowance allocated as of the dated indicated.
	Balance at September 30, 2014
	(Dollars in thousands)	Unpaid			Total recorded				Recorded			Recorded			Related specific
		contractual			investment in				investment			investment			allowance
		principal balance			impaired loans				with no			with
									allowance			allowance
	Commercial real estate	$	16,040		$	13,940			$	13,306		$	634		$	110
	Commercial and industrial	11,986			10,877				4,046			6,831			2,198
	Commercial construction	3,125			2,900				1,082			1,818			690
	Residential	1,699			1,625				1,375			250			103
	Home equity	208			205				—			205			46
	Consumer	22			22				—			22			22
	Total	$	33,080		$	29,569			$	19,809		$	9,760		$	3,169
	Balance at December 31, 2013
	(Dollars in thousands)	Unpaid			Total recorded				Recorded			Recorded			Related specific
		contractual			investment in				investment			investment			allowance
		principal balance			impaired loans				with no			with
									allowance			allowance
	Commercial real estate	$	17,420		$	15,139			$	12,105		$	3,034		$	507
	Commercial and industrial	12,220			10,579				4,902			5,677			2,901
	Commercial construction	3,464			3,358				1,426			1,932			830
	Residential	673			619				365			254			107
	Home equity	110			108				—			108			31
	Consumer	23			23				—			23			23
	Total	$	33,910		$	29,826			$	18,798		$	11,028		$	4,399
	The reduction in related specific reserves on impaired loans was due primarily to increases in estimated current realizable collateral values and current charge-offs of previously allocated specific reserves on commercial relationships for which management deemed collectability of amounts due was unlikely based on current realizable collateral values, partially offset by additional reserves for newly impaired loans during the period.
	The following table presents the average recorded investment in impaired loans and the related interest recognized during the three month periods indicated.
		Three Months Ended September 30, 2014							Three Months Ended September 30, 2013
	(Dollars in thousands)	Average recorded			Interest income				Average recorded			Interest income
		investment			recognized				investment			recognized
	Commercial real estate	$	14,224		$	75			$	15,405		$	42
	Commercial and industrial	10,279			40				9,081			23
	Commercial construction	3,174			27				3,540			17
	Residential	1,294			(2		)		741			3
	Home equity	243			(1		)		109			—
	Consumer	25			1				18			1
	Total	$	29,239		$	140			$	28,894		$	86
	The following table presents the average recorded investment in impaired loans and the related interest recognized during the nine month periods indicated.
		Nine Months Ended September 30, 2014							Nine Months Ended September 30, 2013
	(Dollars in thousands)	Average recorded			Interest income				Average recorded			Interest income
		investment			recognized				investment			recognized
	Commercial real estate	$	13,913		$	169			$	18,572		$	191
	Commercial and industrial	10,482			120				9,312			77
	Commercial construction	3,243			79				3,114			50
	Residential	1,032			1				785			7
	Home equity	215			(1		)		119			—
	Consumer	25			1				17			1
	Total	$	28,910		$	369			$	31,919		$	326
Troubled Debt Restructurings on Financing Receivables	'
	Loans modified as trouble debt restructurings during the three month period ended September 30, 2014 are detailed below.
		Three months ended September 30, 2014
	(Dollars in thousands)	Number of		Pre-modification				Post-modification
		restructurings		outstanding recorded				outstanding recorded
				investment				investment
	Commercial real estate	2		$	1,429			$	1,429
	Commercial and industrial	2		43				43
	Commercial construction	—		—				—
	Residential	—		—				—
	Home equity	—		—				—
	Consumer	—		—				—
	Total	4		$	1,472			$	1,472
	Loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the periods noted are detailed below.
		Three months ended September 30, 2014
	(Dollars in thousands)	Number of TDRs that defaulted		Post-
				modification outstanding
				recorded investment
	Commercial real estate	—		$	—
	Commercial and industrial	—		—
	Commercial construction	—		—
	Residential	1		126
	Home Equity	—		—
	Consumer	—		—
	Total	1		$	126
	Loans modified as troubled debt restructurings during the nine month period ended September 30, 2014 are detailed below.
		Nine months ended September 30, 2014
	(Dollars in thousands)	Number of		Pre-modification				Post-modification
		restructurings		outstanding recorded				outstanding recorded
				investment				investment
	Commercial real estate	3		$	1,979			$	1,979
	Commercial and industrial	8		268				263
	Commercial construction	—		—				—
	Residential	1		124				122
	Home equity	1		73				73
	Consumer	—		—				—
	Total	13		$	2,444			$	2,437
	Loans modified as troubled debt restructurings within the preceding twelve month period for which there was a subsequent payment default during the period noted are detailed below.
		Nine months ended September 30, 2014
	(Dollars in thousands)	Number of TDRs that defaulted		Post-
				modification outstanding
				recorded investment
	Commercial real estate	—		$	—
	Commercial and industrial	1		66
	Commercial construction	—		—
	Residential	1		126
	Home Equity	—		—
	Consumer	—		—
	Total	2		$	192
	Loans modified as troubled debt restructurings during the three month period ended September 30, 2013 are detailed below.
		Three months ended September 30, 2013
	(Dollars in thousands)	Number of		Pre-modification				Post-modification
		restructurings		outstanding recorded				outstanding recorded
				investment				investment
	Commercial real estate	1		$	342			$	291
	Commercial and industrial	1		89				42
	Commercial construction	1		769				769
	Residential	—		—				—
	Home equity	—		—				—
	Consumer	—		—				—
	Total	3		$	1,200			$	1,102
	There were no loans modified as troubled debt restructurings within the twelve month period previous to September 30, 2013 for which there was a subsequent payment default during the three months ended September 30, 2013.
	Loans modified as troubled debt restructurings during the nine month period ended September 30, 2013 are detailed below.
		Nine months ended September 30, 2013
(Dollars in thousands)	Number of		Pre-modification				Post-modification
	restructurings		outstanding recorded				outstanding recorded
			investment				investment
Commercial real estate	1		$	342			$	291
Commercial and industrial	2		189				104
Commercial construction	1		769				769
Residential	—		—				—
Home equity	—		—				—
Consumer	—		—				—
Total	4		$	1,300			$	1,164
Loans modified as troubled debt restructuring within the twelve month period previous to September 30, 2013 for which there was a subsequent payment default during the period noted are detailed below.
	Nine months ended September 30, 2013
(Dollars in thousands)	Number of TDRs that defaulted		Post-
			modification outstanding
			recorded investment
Commercial real estate	1		$	137
Commercial and industrial	1		62
Commercial construction	1		31
Residential	—		—
Home Equity	—		—
Consumer	—		—
Total	3		$	230
Allowance for Credit Losses on Financing Receivables	'
	Changes in the allowance for loan losses by segment for the three months ended September 30, 2014, are presented below:
	(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
		Estate			Industrial				Constr			Mortgage			Equity
	Beginning Balance at June 30, 2014	$	13,065		$	7,550			$	3,741		$	1,266		$	685		$	221	$	26,528
	Provision	154			664				(90		)	(38		)	36			39		765
	Recoveries	—			286				17			—			1			2		306
	Less: Charge offs	92			256				134			46			27			15		570
	Ending Balance at September 30, 2014	$	13,127		$	8,244			$	3,534		$	1,182		$	695		$	247	$	27,029
	Changes in the allowance for loan losses by segment for the nine months ended September 30, 2014, are presented below:
	(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
		Estate			Industrial				Constr			Mortgage			Equity
	Beginning Balance at December 31, 2013	$	13,174		$	8,365			$	3,493		$	1,057		$	653		$	225	$	26,967
	Provision	248			512				128			171			68			38		1,165
	Recoveries	—			510				47			—			1			24		582
	Less: Charge offs	295			1,143				134			46			27			40		1,685
	Ending Balance at September 30, 2014	$	13,127		$	8,244			$	3,534		$	1,182		$	695		$	247	$	27,029
	Ending allowance balance:
	Allotted to loans individually evaluated for impairment	$	110		$	2,198			$	690		$	103		$	46		$	22	$	3,169
	Allotted to loans collectively evaluated for impairment	$	13,017		$	6,046			$	2,844		$	1,079		$	649		$	225	$	23,860
	Changes in the allowance for loan losses by segment for the three months ended September 30, 2013, are presented below:
	(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
		Estate			Industrial				Constr			Mortgage			Equity
	Beginning Balance at June 30, 2013	$	13,020		$	7,633			$	3,154		$	1,033		$	682		$	149	$	25,671
	Provision	162			422				28			(24		)	(34		)	29		583
	Recoveries	34			15				—			—			—			3		52
	Less: Charge offs	192			70				—			36			—			9		307
	Balance at September 30, 2013	$	13,024		$	8,000			$	3,182		$	973		$	648		$	172	$	25,999
	Changes in the allowance for loan losses by segment for the nine months ended September 30, 2013, are presented below:
	(Dollars in thousands)	Cmml Real			Cmml and				Cmml			Resid.			Home			Consumer		Total
		Estate			Industrial				Constr			Mortgage			Equity
	Beginning Balance at December 31, 2012	$	11,793		$	7,297			$	3,456		$	854		$	728		$	126	$	24,254
	Provision	1,342			850				(324		)	27			(57		)	62		1,900
	Recoveries	95			56				50			128			21			9		359
	Less: Charge offs	206			203				—			36			44			25		514
	Ending Balance at September 30, 2013	$	13,024		$	8,000			$	3,182		$	973		$	648		$	172	$	25,999
	Ending allowance balance:
	Allotted to loans individually evaluated for impairment	$	544		$	2,602			$	875		$	68		$	34		$	18	$	4,141
	Allotted to loans collectively evaluated for impairment	$	12,480		$	5,398			$	2,307		$	905		$	614		$	154	$	21,858

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2014
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, fair value, the fair value as a percentage of the market value of the stock at the date of grant and the average assumptions used in the model for the options granted in 2014 and 2013.
		Nine Months Ended September 30,
		2014			2013
	Options granted	31,229			44,475
	Term in years	10			10
	Average assumptions used in the model:
	Expected volatility	47		%	48		%
	Expected dividend yield	2.88		%	2.99		%
	Expected life in years	7			7
	Risk-free interest rate	2.19		%	1.3		%
	Market price on date of grant	$	20.29		$	16.46
	Per share weighted average fair value	$	8.32		$	6.58
	Fair value as a percentage of market value at grant date	41		%	40		%
Schedule of Restricted Stock Awards Granted	'
	The table below provides a summary of restricted stock awards granted in 2014 and 2013.
		Nine Months Ended September 30,
	Restricted Stock Awards	2014			2013
	Two Year Vesting	6,660			6,146
	Four Year Vesting	19,167			25,325
	Performance-Based Vesting	33,017			47,735
	Total Restricted Stock Awards	58,844			79,206
	Weighted average grant date fair value	$	20.29		$	16.45

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2014
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 September 30,		Nine months ended September 30,
		2014	2013	2014	2013
	Basic weighted average common shares outstanding	10,143,055	9,932,060	10,099,593	9,824,984
	Dilutive shares	85,446	94,528	84,671	84,035
	Diluted weighted average common shares outstanding	10,228,501	10,026,588	10,184,264	9,909,019

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2014
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:
			September 30, 2014			Fair Value Measurements using:
	(Dollars in thousands)		Fair Value			(level 1)			(level 2)		(level 3)
	Assets measured on a recurring basis:
	Fixed income securities		$	221,648		$	—		$	221,648	$	—
	Equity securities		15,105			15,105			—		—
	FHLB Stock		3,357			—			—		3,357
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		5,790			—			—		5,790
	Other real estate owned		861			—			—		861
			December 31,			Fair Value Measurements using:
			2013
	(Dollars in thousands)		Fair Value			(level 1)			(level 2)		(level 3)
	Assets measured on a recurring basis:
	Fixed income securities		$	202,201		$	—		$	202,201	$	—
	Equity securities		13,168			13,168			—		—
	FHLB Stock		4,324			—			—		4,324
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		6,542			—			—		6,542
	Other real estate owned		114			—			—		114
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 September 30, 2014.
	(Dollars in thousands)		Fair Value		Valuation Technique	Unobservable Input		Unobservable Input Value or Range
	Assets measured on a recurring basis:
	FHLB Stock		$3,357		FHLB Stated Par Value	N/A		N/A
	Assets measured on a non-recurring basis:
	Impaired loans (collateral dependent)		$5,790		Appraisal of collateral	Appraisal adjustments (1)		5% - 50%
	Other real estate owned		$861		Appraisal of collateral	Appraisal adjustments (1)		0% - 30%
	-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(1) for which fair value is only disclosed but not recognized on the balance sheet at the dates indicated are summarized as follows:
			September 30, 2014						Fair value measurement
	(Dollars in thousands)		Carrying			Fair Value			Level 1 inputs		Level 2 Inputs		Level 3 Inputs
			Amount
	Financial assets:
	Loans held for sale		$	1,645		$	1,645		$	—	$	1,645	—
	Loans, net		1,585,745			1,606,731			—		—		1,606,731
	Financial liabilities:
	Certificates of deposit (including brokered)		271,298			269,999			—		269,999		—
	Borrowed funds		1,004			1,004			—		1,004		—
	Junior subordinated debentures		10,825			12,629			—		—		12,629
			December 31, 2013						Fair value measurement
	(Dollars in thousands)		Carrying			Fair Value			Level 1 inputs		Level 2 Inputs		Level 3 Inputs
			Amount
	Financial assets:
	Loans held for sale		$	1,255		$	1,255		$	—	$	1,255	—
	Loans, net		1,497,089			1,516,809			—		—		1,516,809
	Financial liabilities:
	Certificates of deposit (including brokered)		251,650			250,045			—		250,045		—
	Borrowed funds		36,534			36,535			—		36,535		—
	Junior subordinated debentures		10,825			11,358			—		—		11,358
	-1	Excluded from this table 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.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Details)	9 Months Ended
	Sep. 30, 2014
	segment
	branches
Accounting Policies [Abstract]	'
Number of branches	22
Reportable operating segments	1

Investments_Availableforsale_D

Investments Available-for-sale (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
	investments
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Fair Value	$236,753,000		$215,369,000
Number of securities in loss position	55		'
Investments Temporarily Impaired, Fair Value	78,000,000		'
Securities pledged as collateral	221,600,000		'
Total fixed income securities	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	219,917,000		202,192,000
Unrealized Gains	2,927,000		2,146,000
Unrealized Losses	1,196,000		2,137,000
Fair Value	221,648,000		202,201,000
Federal Agency Obligations	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	54,457,000	[1]	55,440,000	[1]
Unrealized Gains	55,000	[1]	146,000	[1]
Unrealized Losses	174,000	[1]	43,000	[1]
Fair Value	54,338,000	[1]	55,543,000	[1]
Federal Agency mortgage backed securities (MBS)	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	91,875,000	[1]	80,997,000	[1]
Unrealized Gains	613,000	[1]	367,000	[1]
Unrealized Losses	945,000	[1]	1,714,000	[1]
Fair Value	91,543,000	[1]	79,650,000	[1]
Collateralized Mortgage Obligations (CMOs)	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Fair Value	14,300,000		17,400,000
Municipal securities	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	66,544,000		60,675,000
Unrealized Gains	2,201,000		1,604,000
Unrealized Losses	52,000		325,000
Fair Value	68,693,000		61,954,000
Corporate bonds	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	7,041,000		5,080,000
Unrealized Gains	58,000		29,000
Unrealized Losses	25,000		55,000
Fair Value	7,074,000		5,054,000
Equity investments	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	11,543,000		9,960,000
Unrealized Gains	3,568,000		3,228,000
Unrealized Losses	6,000		20,000
Fair Value	15,105,000		13,168,000
Percent of portfolio invested in financial services	16.00%		'
Total available for sale securities, at fair value	'		'
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract]	'		'
Amortized cost	231,460,000		212,152,000
Unrealized Gains	6,495,000		5,374,000
Unrealized Losses	1,202,000		2,157,000
Fair Value	236,753,000		215,369,000
Investments Temporarily Impaired,12 months or longer, Unrealized Losses	$950,000		'
[1]	These categories may include investments issued or guaranteed by government sponsored enterprises such as Fannie Mae (FNMA), Freddie Mac (FHLMC), Ginnie Mae (GNMA), Federal Farm Credit Bank, or one of several Federal Home Loan Banks. All agency MBS/Collateralized Mortgage Obligations ("CMOs") investments owned by the Company are backed by residential mortgages.

Investments_Maturities_Details

Investments Maturities (Details) (USD $)	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]	'
Callable Securities, Fair Value Disclosure	$36,100,000
Total fixed income securities	'
Schedule of Available-for-sale Securities [Line Items]	'
Amortized Cost, Within One Year	9,777,000
Amortized Cost, Within One Year, Yield	1.29%
Fair Value, Within One Year	9,811,000
Amortized Cost Basis, After One, But Within Five Years	59,259,000
Amortized Cost Basis, After One, But Within Five Years, Yield	2.23%
Fair Value, After One, But Within Five Years	60,186,000
Amortized Cost, After Five, But Within Ten Years	56,657,000
Amortized Cost, After Five, But Within Ten Years, Yield	3.18%
Fair Value, after Five but Within Ten Years	57,654,000
Amortized Cost Basis, After Ten Years	94,224,000
Amortized Cost after Ten Years, Yield	2.45%
Fair Value, After Ten Years	93,997,000
Federal agency obligations	'
Schedule of Available-for-sale Securities [Line Items]	'
Amortized Cost, Within One Year	5,003,000
Amortized Cost, Within One Year, Yield	0.59%
Amortized Cost Basis, After One, But Within Five Years	28,011,000
Amortized Cost Basis, After One, But Within Five Years, Yield	1.37%
Amortized Cost, After Five, But Within Ten Years	21,443,000
Amortized Cost, After Five, But Within Ten Years, Yield	1.95%
Amortized Cost Basis, After Ten Years	0
Amortized Cost after Ten Years, Yield	0.00%
MBS	'
Schedule of Available-for-sale Securities [Line Items]	'
Amortized Cost, Within One Year	4,000
Amortized Cost, Within One Year, Yield	1.29%
Amortized Cost Basis, After One, But Within Five Years	2,423,000
Amortized Cost Basis, After One, But Within Five Years, Yield	2.49%
Amortized Cost, After Five, But Within Ten Years	5,896,000
Amortized Cost, After Five, But Within Ten Years, Yield	2.98%
Amortized Cost Basis, After Ten Years	83,552,000
Amortized Cost after Ten Years, Yield	2.16%
Municipal securities	'
Schedule of Available-for-sale Securities [Line Items]	'
Amortized Cost, Within One Year	4,670,000
Amortized Cost, Within One Year, Yield	2.05%
Amortized Cost Basis, After One, But Within Five Years	24,538,000
Amortized Cost Basis, After One, But Within Five Years, Yield	3.30%
Amortized Cost, After Five, But Within Ten Years	26,664,000
Amortized Cost, After Five, But Within Ten Years, Yield	4.24%
Amortized Cost Basis, After Ten Years	10,672,000
Amortized Cost after Ten Years, Yield	4.73%
Corporate bonds	'
Schedule of Available-for-sale Securities [Line Items]	'
Amortized Cost, Within One Year	100,000
Amortized Cost, Within One Year, Yield	1.26%
Amortized Cost Basis, After One, But Within Five Years	4,287,000
Amortized Cost Basis, After One, But Within Five Years, Yield	1.60%
Amortized Cost, After Five, But Within Ten Years	2,654,000
Amortized Cost, After Five, But Within Ten Years, Yield	3.02%
Amortized Cost Basis, After Ten Years	$0
Amortized Cost after Ten Years, Yield	0.00%

Loans_Balance_by_Class_of_Loan

Loans - Balance by Class of Loans (Details) (USD $)	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	$1,614,452	'	$1,525,580	'	'	'
Deferred loan origination fees, net	-1,678	'	-1,524	'	'	'
Total loans	1,612,774	'	1,524,056	'	'	'
Allowance for loan losses	-27,029	-26,528	-26,967	-25,999	-25,671	-24,254
Net Loans	1,585,745	'	1,497,089	'	'	'
Commercial	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	1,382,990	'	1,309,862	'	'	'
Commercial real estate	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	843,648	'	820,299	'	'	'
Allowance for loan losses	-13,127	-13,065	-13,174	-13,024	-13,020	-11,793
Commercial and industrial	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	396,990	'	357,056	'	'	'
Allowance for loan losses	-8,244	-7,550	-8,365	-8,000	-7,633	-7,297
Commercial construction	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	142,352	'	132,507	'	'	'
Allowance for loan losses	-3,534	-3,741	-3,493	-3,182	-3,154	-3,456
Retail	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	231,462	'	215,718	'	'	'
Residential	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	143,825	'	132,721	'	'	'
Allowance for loan losses	-1,182	-1,266	-1,057	-973	-1,033	-854
Home Equity	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	77,983	'	74,354	'	'	'
Allowance for loan losses	-695	-685	-653	-648	-682	-728
Consumer	'	'	'	'	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'	'	'	'	'
Gross loans	9,654	'	8,643	'	'	'
Allowance for loan losses	($247)	($221)	($225)	($172)	($149)	($126)

Loans_Loan_Categories_Narrativ

Loans - Loan Categories Narrative (Details) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
	payment
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	'
Commercial	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Participation loans amount	$51.70	$34.50
Participations loans sold that are still serviced amount	41.4	52.1
Residential	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Early Payment Default Period	4	'
Amount of loans serviced for others	$19.20	$20.60
Residential | Maximum	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Repayment period, term of loan	'30 years	'
Adjustable rate mortgage | Minimum	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Loan-to-value ratio	80.00%	'
Fixed rate mortgage | Maximum	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Loan-to-value ratio	97.00%	'
Home Equity | Maximum	'	'
Schedule of Loans by Loan Classification [Line Items]	'	'
Loan-to-value ratio	80.00%	'
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	'
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	'

Loans_Loans_Serving_as_Collate

Loans - Loans Serving as Collateral (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financial Instruments Owned and Pledged as Collateral [Line Items]	'	'
Loans pledged to the FHLB for borrowing capacity	$412,965	$436,082
Commercial Real Estate	'	'
Financial Instruments Owned and Pledged as Collateral [Line Items]	'	'
Loans pledged to the FHLB for borrowing capacity	289,394	320,908
Residential	'	'
Financial Instruments Owned and Pledged as Collateral [Line Items]	'	'
Loans pledged to the FHLB for borrowing capacity	106,941	97,626
Home Equity	'	'
Financial Instruments Owned and Pledged as Collateral [Line Items]	'	'
Loans pledged to the FHLB for borrowing capacity	$16,630	$17,548

Allowance_For_Loan_Loss_Evalua

Allowance For Loan Loss - Evaluation Method (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	$29,569	$29,826
Loans collectively evaluated for impairment	1,583,205	1,494,230
Gross loans	1,614,452	1,525,580
Deferred loan origination fees, net	-1,678	-1,524
Total loans	1,612,774	1,524,056
Commercial real estate	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	13,940	15,139
Loans collectively evaluated for impairment	829,708	805,160
Gross loans	843,648	820,299
Commercial and industrial	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	10,877	10,579
Loans collectively evaluated for impairment	386,113	346,477
Gross loans	396,990	357,056
Commercial construction	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	2,900	3,358
Loans collectively evaluated for impairment	139,452	129,149
Gross loans	142,352	132,507
Residential	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	1,625	619
Loans collectively evaluated for impairment	142,200	132,102
Gross loans	143,825	132,721
Home Equity	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	205	108
Loans collectively evaluated for impairment	77,778	74,246
Gross loans	77,983	74,354
Consumer	'	'
Schedule of Financing Receivable by Evaluation Method [Line Items]	'	'
Loans individually evaluated for impairment	22	23
Loans collectively evaluated for impairment	9,632	8,620
Gross loans	$9,654	$8,643

Allowance_For_Loan_Loss_Advers

Allowance For Loan Loss - Adversely Classified Loans (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	$1,614,452	$1,525,580
Commercial real estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	843,648	820,299
Commercial and industrial	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	396,990	357,056
Commercial construction	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	142,352	132,507
Residential	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	143,825	132,721
Home Equity	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	77,983	74,354
Consumer	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	9,654	8,643
Substandard	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	26,675	26,363
Substandard | Commercial real estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	9,865	13,545
Substandard | Commercial and industrial	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	11,242	7,908
Substandard | Commercial construction	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	2,983	3,358
Substandard | Residential	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	2,050	1,012
Substandard | Home Equity	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	495	500
Substandard | Consumer	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	40	40
Doubtful	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	1,256	1,317
Doubtful | Commercial real estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	1,207	1,266
Doubtful | Commercial and industrial	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	49	51
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	0	0
Loss	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	120	236
Loss | Commercial real estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	30	0
Loss | Commercial and industrial	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	90	236
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	0
Loss | Consumer	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	0	0
Not Adversely Classified	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	1,586,401	1,497,664
Not Adversely Classified | Commercial real estate	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	832,546	805,488
Not Adversely Classified | Commercial and industrial	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	385,609	348,861
Not Adversely Classified | Commercial construction	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	139,369	129,149
Not Adversely Classified | Residential	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	141,775	131,709
Not Adversely Classified | Home Equity	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	77,488	73,854
Not Adversely Classified | Consumer	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Gross loans	$9,614	$8,603

Allowance_For_Loan_Loss_Past_D

Allowance For Loan Loss - Past Due and Non-Accrual Loans (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
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	'	'
Loans 30-59 Days Past Due	$10,320	$3,445	'
Loans 60-89 Days Past Due	4,208	2,638	'
Non-accrual loans	16,540	18,346	'
Total Past Due Loans	31,068	24,429	'
Current Loans	1,583,384	1,501,151	'
Gross loans	1,614,452	1,525,580	'
The ratio of non-accrual loans to total loans	1.03%	1.20%	1.35%
Additional funding commitments for loans on non-accrual	100	'	'
Commercial real estate	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	4,265	1,142	'
Loans 60-89 Days Past Due	2,902	1,575	'
Non-accrual loans	8,028	10,561	'
Total Past Due Loans	15,195	13,278	'
Current Loans	828,453	807,021	'
Gross loans	843,648	820,299	'
Commercial and industrial	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	1,638	680	'
Loans 60-89 Days Past Due	540	908	'
Non-accrual loans	5,865	5,743	'
Total Past Due Loans	8,043	7,331	'
Current Loans	388,947	349,725	'
Gross loans	396,990	357,056	'
Commercial construction	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	3,833	196	'
Loans 60-89 Days Past Due	68	0	'
Non-accrual loans	669	1,118	'
Total Past Due Loans	4,570	1,314	'
Current Loans	137,782	131,193	'
Gross loans	142,352	132,507	'
Residential	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	537	1,110	'
Loans 60-89 Days Past Due	685	127	'
Non-accrual loans	1,677	633	'
Total Past Due Loans	2,899	1,870	'
Current Loans	140,926	130,851	'
Gross loans	143,825	132,721	'
Home Equity	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	29	211	'
Loans 60-89 Days Past Due	0	10	'
Non-accrual loans	276	281	'
Total Past Due Loans	305	502	'
Current Loans	77,678	73,852	'
Gross loans	77,983	74,354	'
Consumer	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Loans 30-59 Days Past Due	18	106	'
Loans 60-89 Days Past Due	13	18	'
Non-accrual loans	25	10	'
Total Past Due Loans	56	134	'
Current Loans	9,598	8,509	'
Gross loans	9,654	8,643	'
Deposit liabilities reclassified as loans receivable, 90 days or more past due	16	3	'
Not Adversely Classified	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	1,586,401	1,497,664	'
Non-accrual loans not adversely classified	229	577	'
Not Adversely Classified | Commercial real estate	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	832,546	805,488	'
Not Adversely Classified | Commercial and industrial	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	385,609	348,861	'
Not Adversely Classified | Commercial construction	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	139,369	129,149	'
Not Adversely Classified | Residential	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	141,775	131,709	'
Not Adversely Classified | Home Equity	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	77,488	73,854	'
Not Adversely Classified | Consumer	'	'	'
Schedule of Aging of Financing Receivables [Line Items]	'	'	'
Gross loans	$9,614	$8,603	'

Allowance_For_Loan_Loss_Impair

Allowance For Loan Loss - Impaired Loans (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	$29,569,000	'	$29,569,000	'	$29,826,000
Total accruing impaired loans	13,500,000	'	13,500,000	'	11,900,000
Impaired non-accrual loans	16,100,000	'	16,100,000	'	17,900,000
Unpaid contractual principal balance	33,080,000	'	33,080,000	'	33,910,000
Recorded investment with no allowance	19,809,000	'	19,809,000	'	18,798,000
Recorded investment with allowance	9,760,000	'	9,760,000	'	11,028,000
Related allowance	3,169,000	'	3,169,000	'	4,399,000
Average recorded investment	29,239,000	28,894,000	28,910,000	31,919,000	'
Interest income recognized	140,000	86,000	369,000	326,000	'
Additional funding commitments on impaired loans	167,000	'	167,000	'	'
Commercial real estate	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	13,940,000	'	13,940,000	'	15,139,000
Unpaid contractual principal balance	16,040,000	'	16,040,000	'	17,420,000
Recorded investment with no allowance	13,306,000	'	13,306,000	'	12,105,000
Recorded investment with allowance	634,000	'	634,000	'	3,034,000
Related allowance	110,000	'	110,000	'	507,000
Average recorded investment	14,224,000	15,405,000	13,913,000	18,572,000	'
Interest income recognized	75,000	42,000	169,000	191,000	'
Commercial and industrial	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	10,877,000	'	10,877,000	'	10,579,000
Unpaid contractual principal balance	11,986,000	'	11,986,000	'	12,220,000
Recorded investment with no allowance	4,046,000	'	4,046,000	'	4,902,000
Recorded investment with allowance	6,831,000	'	6,831,000	'	5,677,000
Related allowance	2,198,000	'	2,198,000	'	2,901,000
Average recorded investment	10,279,000	9,081,000	10,482,000	9,312,000	'
Interest income recognized	40,000	23,000	120,000	77,000	'
Commercial construction	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	2,900,000	'	2,900,000	'	3,358,000
Unpaid contractual principal balance	3,125,000	'	3,125,000	'	3,464,000
Recorded investment with no allowance	1,082,000	'	1,082,000	'	1,426,000
Recorded investment with allowance	1,818,000	'	1,818,000	'	1,932,000
Related allowance	690,000	'	690,000	'	830,000
Average recorded investment	3,174,000	3,540,000	3,243,000	3,114,000	'
Interest income recognized	27,000	17,000	79,000	50,000	'
Residential	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	1,625,000	'	1,625,000	'	619,000
Unpaid contractual principal balance	1,699,000	'	1,699,000	'	673,000
Recorded investment with no allowance	1,375,000	'	1,375,000	'	365,000
Recorded investment with allowance	250,000	'	250,000	'	254,000
Related allowance	103,000	'	103,000	'	107,000
Average recorded investment	1,294,000	741,000	1,032,000	785,000	'
Interest income recognized	-2,000	3,000	1,000	7,000	'
Home Equity	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	205,000	'	205,000	'	108,000
Unpaid contractual principal balance	208,000	'	208,000	'	110,000
Recorded investment with no allowance	0	'	0	'	0
Recorded investment with allowance	205,000	'	205,000	'	108,000
Related allowance	46,000	'	46,000	'	31,000
Average recorded investment	243,000	109,000	215,000	119,000	'
Interest income recognized	-1,000	0	-1,000	0	'
Consumer	'	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'	'
Total recorded investment in impaired loans	22,000	'	22,000	'	23,000
Unpaid contractual principal balance	22,000	'	22,000	'	23,000
Recorded investment with no allowance	0	'	0	'	0
Recorded investment with allowance	22,000	'	22,000	'	23,000
Related allowance	22,000	'	22,000	'	23,000
Average recorded investment	25,000	18,000	25,000	17,000	'
Interest income recognized	$1,000	$1,000	$1,000	$1,000	'

Allowance_For_Loan_Loss_Troubl

Allowance For Loan Loss - Troubled Debt Restructures (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
	restructuring	restructuring	restructuring	restructuring
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Total Troubled Debt Restructure (TDR) loans	$20,700,000	'	$20,700,000	'	$20,900,000
TDR loans on accrual status	13,000,000	'	13,000,000	'	11,400,000
TDR loans included in non-performing loans	7,700,000	'	7,700,000	'	9,500,000
Additional Funding Commitments on TDR loans	75,000	'	75,000	'	'
Number of restructurings	4	3	13	4	'
Pre-modification outstanding recorded investment	1,472,000	1,200,000	2,444,000	1,300,000	'
Post-modification outstanding recorded investment	1,472,000	1,102,000	2,437,000	1,164,000	'
Number of TDR's that defaulted	1	0	2	3	'
Post-modification outstanding recorded investment	126,000	'	192,000	230,000	'
Specific reserves allocated to TDRs	45,000	80,000	45,000	80,000	'
Interest payments received on nonaccruing TDR loans excluded from income	'	'	5,000	'	'
Charge-offs associated with TDRs	'	'	66,000	38,000	'
Number of TDRs transferred to OREO durng the period	'	'	'	2	'
Carry value of TDRs transferred to OREO during the period	'	'	'	168,000	'
Commercial real estate	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	2	1	3	1	'
Pre-modification outstanding recorded investment	1,429,000	342,000	1,979,000	342,000	'
Post-modification outstanding recorded investment	1,429,000	291,000	1,979,000	291,000	'
Number of TDR's that defaulted	0	'	0	1	'
Post-modification outstanding recorded investment	0	'	0	137,000	'
Commercial and industrial	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	2	1	8	2	'
Pre-modification outstanding recorded investment	43,000	89,000	268,000	189,000	'
Post-modification outstanding recorded investment	43,000	42,000	263,000	104,000	'
Number of TDR's that defaulted	0	'	1	1	'
Post-modification outstanding recorded investment	0	'	66,000	62,000	'
Commercial construction	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	0	1	0	1	'
Pre-modification outstanding recorded investment	0	769,000	0	769,000	'
Post-modification outstanding recorded investment	0	769,000	0	769,000	'
Number of TDR's that defaulted	0	'	0	1	'
Post-modification outstanding recorded investment	0	'	0	31,000	'
Residential	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	0	0	1	0	'
Pre-modification outstanding recorded investment	0	0	124,000	0	'
Post-modification outstanding recorded investment	0	0	122,000	0	'
Number of TDR's that defaulted	1	'	1	0	'
Post-modification outstanding recorded investment	126,000	'	126,000	0	'
Home Equity	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	0	0	1	0	'
Pre-modification outstanding recorded investment	0	0	73,000	0	'
Post-modification outstanding recorded investment	0	0	73,000	0	'
Number of TDR's that defaulted	0	'	0	0	'
Post-modification outstanding recorded investment	0	'	0	0	'
Consumer	'	'	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'	'	'
Number of restructurings	0	0	0	0	'
Pre-modification outstanding recorded investment	0	0	0	0	'
Post-modification outstanding recorded investment	0	0	0	0	'
Number of TDR's that defaulted	0	'	0	0	'
Post-modification outstanding recorded investment	$0	'	$0	$0	'

Allowance_For_Loan_Loss_Other_

Allowance For Loan Loss - Other Real Estate Owned (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Carry value of OREO	$861	'	$114
Net gains on sales of OREO	0	121	'
OREO fair value adjustment	0	23	'
Other real estate owned	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'
Number of OREO properties added	2	'	'
Number of OREO properties owned	3	'	1
OREO fair value adjustment	'	$23	'

Allowance_For_Loan_Loss_Allowa

Allowance For Loan Loss - Allowance for Loan Losses (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'
Allowance for loan losses to total loans ratio	1.68%	1.77%	1.68%	1.77%	1.77%
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	$26,528	$25,671	$26,967	$24,254	'
Provision for loan losses	765	583	1,165	1,900	'
Recoveries	306	52	582	359	'
Less: Charge offs	570	307	1,685	514	'
Ending Balance	27,029	25,999	27,029	25,999	'
Allotted to loans individually evaluated for impairment	3,169	4,141	3,169	4,141	'
Allotted to loans collectively evaluated for impairment	23,860	21,858	23,860	21,858	'
Commercial real estate	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	13,065	13,020	13,174	11,793	'
Provision for loan losses	154	162	248	1,342	'
Recoveries	0	34	0	95	'
Less: Charge offs	92	192	295	206	'
Ending Balance	13,127	13,024	13,127	13,024	'
Allotted to loans individually evaluated for impairment	110	544	110	544	'
Allotted to loans collectively evaluated for impairment	13,017	12,480	13,017	12,480	'
Commercial and industrial	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	7,550	7,633	8,365	7,297	'
Provision for loan losses	664	422	512	850	'
Recoveries	286	15	510	56	'
Less: Charge offs	256	70	1,143	203	'
Ending Balance	8,244	8,000	8,244	8,000	'
Allotted to loans individually evaluated for impairment	2,198	2,602	2,198	2,602	'
Allotted to loans collectively evaluated for impairment	6,046	5,398	6,046	5,398	'
Commercial construction	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	3,741	3,154	3,493	3,456	'
Provision for loan losses	-90	28	128	-324	'
Recoveries	17	0	47	50	'
Less: Charge offs	134	0	134	0	'
Ending Balance	3,534	3,182	3,534	3,182	'
Allotted to loans individually evaluated for impairment	690	875	690	875	'
Allotted to loans collectively evaluated for impairment	2,844	2,307	2,844	2,307	'
Residential	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	1,266	1,033	1,057	854	'
Provision for loan losses	-38	-24	171	27	'
Recoveries	0	0	0	128	'
Less: Charge offs	46	36	46	36	'
Ending Balance	1,182	973	1,182	973	'
Allotted to loans individually evaluated for impairment	103	68	103	68	'
Allotted to loans collectively evaluated for impairment	1,079	905	1,079	905	'
Home Equity	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	685	682	653	728	'
Provision for loan losses	36	-34	68	-57	'
Recoveries	1	0	1	21	'
Less: Charge offs	27	0	27	44	'
Ending Balance	695	648	695	648	'
Allotted to loans individually evaluated for impairment	46	34	46	34	'
Allotted to loans collectively evaluated for impairment	649	614	649	614	'
Consumer	'	'	'	'	'
Allowance for Loan and Lease Losses [Roll Forward]	'	'	'	'	'
Beginning Balance	221	149	225	126	'
Provision for loan losses	39	29	38	62	'
Recoveries	2	3	24	9	'
Less: Charge offs	15	9	40	25	'
Ending Balance	247	172	247	172	'
Allotted to loans individually evaluated for impairment	22	18	22	18	'
Allotted to loans collectively evaluated for impairment	$225	$154	$225	$154	'

Supplemental_Retirement_Plan_a1

Supplemental Retirement Plan and Other Postretirement Benefit Obligations (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
	officer		officer
Supplemental Retirement Plan	'	'	'	'
Defined Benefit Plan Disclosures [Line Items]	'	'	'	'
Defined Benefit Plan, Number of Active Executive Officers under Plan	2	'	2	'
Defined Benefit Plan, Number of Former Executive Officers under Plan	1	'	1	'
Term of SERP benefits	'	'	'20 years	'
Net Periodic Benefit Cost, Interest Only	$36	$33	$107	$100
Benefits Paid	69	69	207	207
Remaining accrual for benefit obligation in current year	'	'	36	'
Supplemental Life Insurance Plan	'	'	'	'
Defined Benefit Plan Disclosures [Line Items]	'	'	'	'
Net Periodic Benefit Cost, Interest Only	$19	$18	$55	$54

StockBased_Compensation_Summar

Stock-Based Compensation Summary Information for Options Granted (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock option awards granted	31,229	44,475
Stock options	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Term in years	'10 years	'10 years
Expected volatility	47.00%	48.00%
Market price on date of grant	20.29	16.46
Per share weighted average fair value	8.32	6.58
Weighted Average | Stock options	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Expected dividend yield	2.88%	2.99%
Expected life in years	'7 years	'7 years
Risk-free interest rate	2.19%	1.30%
Fair Value as a percentage of market value at grant date	41.00%	40.00%

StockBased_Compensation_Stock_

Stock-Based Compensation Stock Options, Restricted Stock Awards, and Stock in Lieu of Directors' Fees (Details) (USD $)

1 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

12 Months Ended

9 Months Ended

In Thousands, except Share data, unless otherwise specified

Jan. 31, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Jan. 02, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2014

Jan. 31, 2014

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Stock options

Stock options

Stock options

Stock options

Restricted Stock

Restricted Stock

Restricted Stock

Restricted Stock

Restricted Stock

Restricted Stock

Common Stock

Common stock in lieu of cash

Common stock in lieu of cash

Common stock in lieu of cash

Common stock in lieu of cash

Common stock in lieu of cash

Year Two

Year Two

Vesting, Year Four

Vesting, Year Four

Employee

Director

Director

Director

Director

Director

Director

Stock options

Stock options

Stock options

Stock options

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock-based compensation expense

'

$409

$380

$1,325

$1,239

'

$87

$75

$277

$344

$278

$265

$868

$746

'

'

'

$44

$40

$180

$149

$194

'

'

'

'

Options granted, vesting percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50.00%

50.00%

50.00%

50.00%

Award vesting period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'4 years

'2 years

'

'

'

'

'

'

'

'

'

'

Stock awards in period

'

'

'

'

'

'

'

'

'

'

'

'

58,844

79,206

'

'

2,142

'

'

'

'

'

'

'

'

'

Weighted Average Grant Date Fair Value, Stock Awards

'

'

'

'

'

'

'

'

'

'

'

'

$20.29

$16.45

'

'

$20.95

'

'

'

'

'

'

'

'

'

Number of shares issued in lieu of cash to directors

11,136

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair market share price

'

'

'

'

'

$17.43

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

StockBased_Compensation_Restri

Stock-Based Compensation Restricted Stock Grants (Details) (Restricted Stock, USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock awards in period	58,844	79,206
Weighted Average Grant Date Fair Value, Stock Awards	$20.29	$16.45
Director | Two year vesting	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock awards in period	6,660	6,146
Employee | Four year vesting	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock awards in period	19,167	25,325
Employee | Performance-based vesting	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Stock awards in period	33,017	47,735

Earnings_Per_Share_Earnings_Pe

Earnings Per Share Earnings Per Share (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Basic weighted average common shares outstanding	10,143,055	9,932,060	10,099,593	9,824,984
Dilutive shares	85,446	94,528	84,671	84,035
Diluted weighted average common shares outstanding	10,228,501	10,026,588	10,184,264	9,909,019
Stock options	'	'	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Antidilutive securities excluded from computation of earnings per share	'	'	22,776	'

Fair_Value_Measurements_Recurr

Fair Value Measurements - Recurring and Nonrecurring Basis (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Specific allowance for collateral dependent impaired loans	$2,400,000	'	$3,200,000
Net gains on sales of OREO	0	121,000	'
OREO fair value adjustment	0	23,000	'
Other real estate owned	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
OREO fair value adjustment	'	23,000	'
Fair Value, Measurements, Recurring | Fair Value | Fixed income securities	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Fair value of assets	221,648,000	'	202,201,000
Fair Value, Measurements, Recurring | Fair Value | Equity securities	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Fair value of assets	15,105,000	'	13,168,000
Fair Value, Measurements, Recurring | Fair Value | FHLB Stock	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Fair value of assets	3,357,000	'	4,324,000
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	15,105,000	'	13,168,000
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	221,648,000	'	202,201,000
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	3,357,000	'	4,324,000
Fair Value, Measurements, Nonrecurring | Fair Value	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Impaired loans (collateral dependent), Fair Value	5,790,000	'	6,542,000
Other real estate owned, Fair Value	861,000	'	114,000
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	5,790,000	'	6,542,000
Other real estate owned, Fair Value	$861,000	'	$114,000

Fair_Value_Measurements_Quanti

Fair Value Measurements - Quantitative (Details) (Fair Value, Inputs, Level 3, USD $)

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Dec. 31, 2013

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

In Thousands, unless otherwise specified

Fair Value, Measurements, Recurring

Fair Value, Measurements, Recurring

Fair Value, Measurements, Recurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

Fair Value, Measurements, Nonrecurring

FHLB Stock

FHLB Stock

FHLB Stock

Impaired loans (collateral dependent)

Impaired loans (collateral dependent)

Impaired loans (collateral dependent)

Other real estate owned

Other real estate owned

Other real estate owned

FHLB Stated Par Value

Appraisal of collateral

Appraisal of collateral

Appraisal of collateral

Appraisal of collateral

Appraisal of collateral

Appraisal of collateral

Minimum

Maximum

Minimum

Maximum

Fair Value Inputs, Assets, Quantitative Information [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Fair value of assets

$3,357

$4,324

$3,357

'

'

'

'

'

'

'

'

Impaired loans (collateral dependent), Fair Value

'

'

'

5,790

6,542

5,790

[1]

'

'

'

'

'

Other real estate owned, Fair Value

'

'

'

$861

$114

'

'

'

$861

[1]

'

'

Unobservable Input Value or Range

'

'

'

'

'

'

5.00%

50.00%

'

0.00%

30.00%

[1]

Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses.

Fair_Value_Measurements_Other_

Fair Value Measurements - Other Guarantees and Commitments (Details) (Financial Standby Letter of Credit)	9 Months Ended
	Sep. 30, 2014
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

Fair_Value_Measurements_Balanc

Fair Value Measurements - Balance Sheet Grouping (Details) (USD $)	Sep. 30, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair Value	'		'
Financial assets:	'		'
Loans held for sale	$1,645	[1]	$1,255	[1]
Loans, net	1,606,731	[1]	1,516,809	[1]
Financial liabilities:	'		'
Borrowed funds	1,004	[1]	36,535	[1]
Junior subordinated debentures	12,629	[1]	11,358	[1]
Fair Value, Inputs, Level 1	'		'
Financial assets:	'		'
Loans held for sale	0	[1]	0	[1]
Loans, net	0	[1]	0	[1]
Financial liabilities:	'		'
Borrowed funds	0	[1]	0	[1]
Junior subordinated debentures	0	[1]	0	[1]
Fair Value, Inputs, Level 2	'		'
Financial assets:	'		'
Loans held for sale	1,645	[1]	1,255	[1]
Loans, net	0	[1]	0	[1]
Financial liabilities:	'		'
Borrowed funds	1,004	[1]	36,535	[1]
Junior subordinated debentures	0	[1]	0	[1]
Fair Value, Inputs, Level 3	'		'
Financial assets:	'		'
Loans held for sale	0	[1]	0	[1]
Loans, net	1,606,731	[1]	1,516,809	[1]
Financial liabilities:	'		'
Borrowed funds	0	[1]	0	[1]
Junior subordinated debentures	12,629	[1]	11,358	[1]
Carrying Amount	'		'
Financial assets:	'		'
Loans held for sale	1,645	[1]	1,255	[1]
Loans, net	1,585,745	[1]	1,497,089	[1]
Financial liabilities:	'		'
Borrowed funds	1,004	[1]	36,534	[1]
Junior subordinated debentures	10,825	[1]	10,825	[1]
Certificates of deposit | Fair Value	'		'
Financial liabilities:	'		'
Certificates of deposit	269,999	[1]	250,045	[1]
Certificates of deposit | Fair Value, Inputs, Level 1	'		'
Financial liabilities:	'		'
Certificates of deposit	0	[1]	0	[1]
Certificates of deposit | Fair Value, Inputs, Level 2	'		'
Financial liabilities:	'		'
Certificates of deposit	269,999	[1]	250,045	[1]
Certificates of deposit | Fair Value, Inputs, Level 3	'		'
Financial liabilities:	'		'
Certificates of deposit	0	[1]	0	[1]
Certificates of deposit | Carrying Amount	'		'
Financial liabilities:	'		'
Certificates of deposit	$271,298	[1]	$251,650	[1]
[1]	Excluded from this table 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.