United Financial Bancorp 10-Q 8 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 30, 2013
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'UBNK	'
Entity Registrant Name	'United Financial Bancorp, Inc.	'
Entity Central Index Key	'0001405049	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	19,678,034

Consolidated_Statements_of_Con

Consolidated Statements of Condition (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
ASSETS	'	'
Cash and due from banks	$35,257	$28,972
Interest-bearing deposits	23,703	1,707
Total cash and cash equivalents	58,960	30,679
Securities available for sale, at fair value	264,423	294,322
Securities held to maturity, at amortized cost (fair value of $99,393 at September 30, 2013 and $85,674 at December 31, 2012)	97,991	82,986
Loans held for sale	'	632
Loans, net of allowance for loan losses of $13,642 at September 30, 2013 and $12,089 at December 31, 2012	1,882,508	1,807,401
Other real estate owned	2,206	2,578
Accrued interest receivable	6,355	6,790
Deferred tax asset, net	21,226	20,178
Stock in the Federal Home Loan Bank of Boston	17,334	18,554
Banking premises and equipment, net	25,474	25,064
Bank-owned life insurance	54,157	52,876
Goodwill	40,992	39,852
Other assets	19,111	20,391
TOTAL ASSETS	2,490,737	2,402,303
Deposits:	'	'
Interest-bearing	1,613,192	1,540,873
Non-interest-bearing	333,206	307,302
Total deposits	1,946,398	1,848,175
Short-term borrowings	60,446	79,229
Long-term debt	153,662	133,969
Subordinated debentures	5,933	9,630
Escrow funds held for borrowers	3,375	4,315
Capitalized lease obligations	4,583	4,711
Accrued expenses and other liabilities	13,582	15,085
Total liabilities	2,187,979	2,095,114
Stockholders' equity:	'	'
Preferred stock, par value $0.01 per share, authorized 50,000,000 shares; none issued	'	'
Common stock, par value $0.01 per share, authorized 100,000,000 shares; 24,266,428 shares issued at September 30, 2013 and December 31, 2012	243	243
Paid-in capital	273,121	272,822
Retained earnings	94,219	87,153
Treasury stock, at cost (4,588,394 shares at September 30, 2013 and 4,114,310 shares at December 31, 2012)	-65,506	-58,430
Accumulated other comprehensive income, net of taxes	681	5,401
Total stockholders' equity	302,758	307,189
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$2,490,737	$2,402,303

Consolidated_Statements_of_Con1

Consolidated Statements of Condition (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Securities held to maturity, fair value	$99,393	$85,674
Loans, allowance for loan losses	$13,642	$12,089
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	24,266,428	24,266,428
Treasury stock, shares	4,588,394	4,114,310

Consolidated_Statements_of_Net

Consolidated Statements of Net Income (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Interest and dividend income:	'	'	'	'
Loans	$20,974	$14,494	$64,307	$42,750
Investments	2,226	2,549	6,787	8,171
Other interest-earning assets	26	27	68	119
Total interest and dividend income	23,226	17,070	71,162	51,040
Interest expense:	'	'	'	'
Deposits	2,898	2,444	8,552	7,795
Short-term borrowings	23	12	72	46
Long-term debt	959	1,064	3,000	3,255
Total interest expense	3,880	3,520	11,624	11,096
Net interest income before provision for loan losses	19,346	13,550	59,538	39,944
Provision for loan losses	1,125	1,050	2,967	2,450
Net interest income after provision for loan losses	18,221	12,500	56,571	37,494
Non-interest income:	'	'	'	'
Fee income on depositors' accounts	1,633	1,452	4,729	4,389
Wealth management income	269	279	727	795
Income from bank-owned life insurance	518	448	1,541	1,324
Net gain on sales of loans	'	188	213	458
Net gain (loss) on sales of securities	'	27	-50	27
Impairment charges on securities	'	-202	'	-202
Other income	556	319	1,629	863
Total non-interest income	2,976	2,511	8,789	7,654
Non-interest expense:	'	'	'	'
Salaries and benefits	8,109	6,375	24,733	19,103
Occupancy expenses	1,362	823	4,317	2,567
Marketing expenses	426	316	1,657	1,257
Data processing expenses	1,428	1,109	4,243	3,140
Professional fees	587	372	1,914	1,282
Acquisition related expenses	'	366	281	958
Branch closing expenses	'	'	987	'
FDIC insurance assessments	408	264	1,231	800
Tax credit funds	390	'	930	243
Other expenses	2,126	1,567	6,662	4,585
Total non-interest expense	14,836	11,192	46,955	33,935
Income before income taxes	6,361	3,819	18,405	11,213
Income tax expense	1,714	890	5,008	2,853
Net income	$4,647	$2,929	$13,397	$8,360
Earnings per share:	'	'	'	'
Basic	$0.24	$0.20	$0.68	$0.57
Diluted	$0.23	$0.20	$0.67	$0.56
Weighted average shares outstanding:	'	'	'	'
Basic	19,652,925	14,522,324	19,800,557	14,578,253
Diluted	19,972,802	14,708,373	20,078,865	14,827,428
Dividends paid per share	$0.11	$0.10	$0.32	$0.28

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	3 Months Ended			9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'	'		'		'
Net income	$4,647	$2,929		$13,397		$8,360
Unrealized gains (losses) on securities:	'	'		'		'
Unrealized holding gains (losses) on available-for-sale securities	51	1,050		-7,694		1,089
Reclassification adjustment for losses realized in income	'	138	[1]	50	[1]	138	[1]
Net change in unrealized gains	51	1,188		-7,644		1,227
Tax effect	-13	-449		2,924		-465
Net of tax amount	38	739		-4,720		762
Comprehensive income	$4,685	$3,668		$8,677		$9,122
[1]	Amounts are included in net gains (loss) on sales of securities in non-interest income on the consolidated statements of net income. Income tax benefit associated with their reclassification adjustments was $0 and $52 for the three monts ended September 30, 2013 and 2012, respectively, and $19 and $52 for the nine months ended September 30, 2013 and 2012, respectively.

Consolidated_Statements_of_Com1

Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'	'	'	'
Income tax benefit through reclassification adjustments	$0	$52	$19	$52

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)	Total	Common Stock [Member]	Paid-In Capital [Member]	Retained Earnings [Member]	Unearned Compensation [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
In Thousands, except Share data
Balances at Dec. 31, 2011	$227,361	$187	$182,433	$89,019	($10,047)	($40,983)	$6,752
Balances, shares at Dec. 31, 2011	'	15,712,897	'	'	'	'	'
Net income	8,360	'	'	8,360	'	'	'
Other comprehensive income (loss)	762	'	'	'	'	'	762
Cash dividends paid	-4,077	'	'	-4,077	'	'	'
Treasury stock purchases	-4,045	'	'	'	'	-4,045	'
Treasury stock purchases, shares	'	-260,914	'	'	'	'	'
Shares repurchased in connection with restricted stock forfeited for tax purposes	-151	'	'	'	'	-151	'
Shares repurchased in connection with restricted stock forfeited for tax purposes, shares	'	-11,013	'	'	'	'	'
Restricted shares forfeited	'	'	151	'	'	-151	'
Restricted shares forfeited, shares	'	-11,000	'	'	'	'	'
Excess tax benefit on stock compensation plans	29	'	29	'	'	'	'
Cancellation of shares for tax withholdings on options exercised	-92	'	-92	'	'	'	'
Reissuance of treasury shares in connection with stock options exercised	98	'	-172	-10	'	280	'
Reissuance of treasury shares in connection with stock options exercised, shares	'	20,351	'	'	'	'	'
Reissuance of treasury shares in connection with restricted stock grants	'	'	-267	25	'	242	'
Reissuance of treasury shares in connection with restricted stock grants, shares	'	17,500	'	'	'	'	'
Stock-based compensation	1,103	'	1,103	'	'	'	'
ESOP shares committed to be released	815	'	291	'	524	'	'
Balances at Sep. 30, 2012	230,163	187	183,476	93,317	-9,523	-44,808	7,514
Balances, shares at Sep. 30, 2012	'	15,467,821	'	'	'	'	'
Balances at Dec. 31, 2012	307,189	243	272,822	87,153	'	-58,430	5,401
Balances, shares at Dec. 31, 2012	'	20,152,118	'	'	'	'	'
Net income	13,397	'	'	13,397	'	'	'
Other comprehensive income (loss)	-4,720	'	'	'	'	'	-4,720
Cash dividends paid	-6,331	'	'	-6,331	'	'	'
Treasury stock purchases	-7,280	'	'	'	'	-7,280	'
Treasury stock purchases, shares	'	-489,351	'	'	'	'	'
Shares repurchased in connection with restricted stock forfeited for tax purposes	-191	'	'	'	'	-191	'
Shares repurchased in connection with restricted stock forfeited for tax purposes, shares	'	-12,669	'	'	'	'	'
Restricted shares forfeited	'	'	75	'	'	-75	'
Restricted shares forfeited, shares	'	-5,000	'	'	'	'	'
Excess tax benefit on stock compensation plans	64	'	64	'	'	'	'
Cancellation of shares for tax withholdings on options exercised	-249	'	-249	'	'	'	'
Reissuance of treasury shares in connection with stock options exercised	'	'	-470	'	'	470	'
Reissuance of treasury shares in connection with stock options exercised, shares	'	32,936	'	'	'	'	'
Stock-based compensation	879	'	879	'	'	'	'
Balances at Sep. 30, 2013	$302,758	$243	$273,121	$94,219	'	($65,506)	$681
Balances, shares at Sep. 30, 2013	'	19,678,034	'	'	'	'	'

Consolidated_Statements_of_Sto1

Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash dividends paid, per share	$0.32	$0.28
Retained Earnings [Member]	'	'
Cash dividends paid, per share	$0.32	$0.28

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:	'	'
Net income	$13,397	$8,360
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Provision for loan losses	2,967	2,450
ESOP expense	'	815
Stock-based compensation	879	1,103
Excess tax benefits on stock compensation plan	-64	-29
Amortization of premiums and discounts	2,152	1,508
Depreciation and amortization	2,229	1,260
Amortization of intangible assets	578	70
Net (loss) gain on sale and writedown of other real estate owned	-12	362
Impairment charges on securities	'	202
Net loss (gain) on sale of available for sale securities	50	-27
Loans originated for sale	-7,498	-13,392
Proceeds from sales of loans held for sale	8,343	13,903
Net gain on sale of loans	-213	-458
Deferred tax (benefit) provision	-1,048	235
Net increase in cash surrender value of bank-owned life insurance	-1,281	-1,181
Decrease in accrued interest receivable	435	76
Decrease (increase) in other assets	2,486	-5,208
(Decrease) increase in accrued expenses and other liabilities	-1,263	1,675
Net cash provided by operating activities	22,137	11,724
Cash flows from investing activities:	'	'
Purchases of securities available for sale	-43,887	-65,976
Proceeds from sales of securities available for sale	2,563	2,517
Proceeds from maturities, calls and principal repayments of securities available for sale	62,029	46,957
Purchases of securities held to maturity	-33,746	-1,455
Proceeds from maturities, calls and principal repayments of securities held to maturity	18,089	24,937
Redemption of Federal Home Loan Bank of Boston stock	1,220	911
Proceeds from sales of other real estate owned	2,650	1,851
Net loan originations, purchases and principal repayments	-80,340	-98,919
Purchases of property and equipment	-2,625	-2,957
Net cash used in investing activities	-74,047	-92,134
Cash flows from financing activities:	'	'
Net increase in deposits	98,223	45,185
Net change in short-term borrowings	-18,783	-2,681
Proceeds from issuance of long-term debt	51,492	26,627
Repayment of long-term debt, net of amortization of discount	-31,496	-13,128
Redemption of trust preferred securities	-4,000	'
Net decrease in escrow funds held for borrowers	-940	-211
Payments on capitalized lease obligations	-318	-318
Excess tax benefits on stock compensation plan	64	29
Cancellation of shares for tax withholdings on options exercised	-249	-92
Reissuance of treasury shares in connection with stock options exercised	'	98
Treasury stock purchases	-7,471	-4,196
Cash dividends paid	-6,331	-4,077
Net cash provided by financing activities	80,191	47,236
Increase (decrease) in cash and cash equivalents	28,281	-33,174
Cash and cash equivalents at beginning of period	30,679	61,518
Cash and cash equivalents at end of period	58,960	28,344
Cash paid during the period:	'	'
Interest on deposits, borrowings and other interest bearing liabilities	14,290	11,512
Income taxes - net	5,820	5,409
Non-cash items:	'	'
Transfer of loans to other real estate owned	$2,266	$1,508

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Basis of Presentation	'
	NOTE A – BASIS OF PRESENTATION
	The consolidated financial statements include the accounts of United Financial Bancorp, Inc. (“United Financial”), its wholly-owned subsidiary, United Bank (the “Bank”), and the Bank’s wholly-owned subsidiaries, UCB Securities, Inc. and UCB Securities, Inc. II, which are engaged in buying, selling and holding investment securities, and UB Properties, LLC and VB REO, LLC, which were formed to hold real estate assets acquired through foreclosure. All significant intercompany accounts and transactions have been eliminated in consolidation. These entities are collectively referred to herein as the “Company”.
	The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and with general practices within the banking industry. In the opinion of management, the accompanying unaudited interim consolidated financial statements reflect all adjustments, consisting of normal recurring adjustments, which are necessary for the fair presentation of the Company’s financial condition as of September 30, 2013 and the results of operations for the three and nine months ended September 30, 2013 and 2012. The interim results of operations presented herein are not necessarily indicative of the results to be expected for the entire year or any other period. These financial statements should be read in conjunction with the consolidated financial statements and the notes thereto for the year ended December 31, 2012 included in the Company’s Annual Report on Form 10-K, which was filed with the Securities and Exchange Commission on March 15, 2013.

Recent_Accounting_Pronouncemen

Recent Accounting Pronouncements	9 Months Ended
	Sep. 30, 2013
Accounting Changes And Error Corrections [Abstract]	'
Recent Accounting Pronouncements	'
	NOTE B – RECENT ACCOUNTING PRONOUNCEMENTS
	In October 2012, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2012-04, Technical Amendments and Corrections to SEC Sections 2011-08. This ASU is intended to clarify the FASB Accounting Standards Codification (“Codification”), correct unintended application of guidance and includes amendments identifying when the use of fair value should be linked to the definition of fair value in Topic 820, Fair Value Measurement. Amendments to the Codification without transition guidance are effective upon issuance for both public and non-public entities. This ASU was adopted in the first quarter of 2013 and did not have a material impact on the Company’s consolidated financial statements.
	In February 2013, the FASB issued ASU 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. This Update requires entities to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, entities are required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line item of net income. The Company adopted this ASU in the first quarter of 2013 and there was no impact on the Company’s consolidated financial results as the amendments relate only to disclosures in the consolidated financial statements.
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force). This Update provides that an unrecognized tax benefit, or a portion thereof, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, except to the extent that a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date to settle any additional income taxes that would result from disallowance of a tax position, or the tax law does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, then the unrecognized tax benefit should be presented as a liability. This ASU is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The Company does not expect that the adoption of this ASU will have an impact on the Company’s consolidated financial statements.

Critical_Accounting_Policies

Critical Accounting Policies	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Critical Accounting Policies	'
	NOTE C – CRITICAL ACCOUNTING POLICIES
	The SEC defines “critical accounting policies” as those that require application of management’s most difficult, subjective or complex judgments, often as a result of the need to make estimates about the effect of matters that are inherently uncertain and may change in future periods. Management believes that the following policies would be considered critical under the SEC’s definition:
	Allowance for Loan Losses. The allowance for loan losses is the amount estimated by management as necessary to cover credit losses inherent in the loan portfolio at the balance sheet date. The allowance is established through the provision for loan losses which is charged against income. The methodology for determining the allowance for loan losses is considered a critical accounting policy by management due to the high degree of judgment involved, the subjectivity of the assumptions utilized and the potential for changes in the economic environment that could result in adjustments to the amount of the recorded allowance for loan losses.
	Management performs a quarterly evaluation of the adequacy of the allowance for loan losses. We consider a variety of factors in establishing this estimate including, but not limited to, prior loss experience, current economic conditions, trends in non-performing, classified and impaired loans, charge-offs and delinquency rates, the adequacy of the underlying collateral, the size and composition of the loan portfolio, the financial strength of the borrower, results of internal loan reviews and other relevant factors. This evaluation is inherently subjective as it requires material estimates by management that may be susceptible to significant change based on changes in economic and real estate market conditions.
	A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired.
	The Company periodically may agree to modify the contractual terms of loans. A loan is classified as a troubled debt restructuring (“TDR”) if the Company grants a concession to a borrower that is experiencing financial difficulties. This usually includes a modification of loan terms, such as a reduction of the interest rate to below market terms, capitalizing past due interest, extending the maturity date or a partial forgiveness of debt. A TDR loan is returned to accrual status after the borrower demonstrates the ability to pay under the restructured terms through a sustained period of repayment performance, which is generally six months. All TDRs are classified as impaired.
	The allowance consists of a specific, general, and unallocated component, as further described below.
	Specific component. The specific component relates to loans that are classified as impaired. Impairment is measured on a loan by loan basis for the commercial segments (commercial and industrial, commercial real estate and construction) by either the present value of expected future cash flows discounted at the loan’s effective interest rate or the fair value of the collateral if the loan is collateral dependent. A specific allowance is established when the discounted cash flows (or collateral value) of the impaired loan is lower than the carrying value of the loan. Groups of smaller balance homogenous loans are collectively evaluated for impairment. Accordingly, the Company does not separately identify individual loans in the consumer segments (residential real estate, home equity and consumer loans) for impairment disclosures, unless such loans are subject to a troubled debt restructuring agreement.
	The Company has established a Business Banking unit within its Commercial Lending Department. The portfolio is made up of both commercial and industrial loans less than $250 and commercial real estate loans less than $500 which are managed by exception. This grouping of loans is considered a homogenous pool of loans and collectively evaluated for impairment. Accordingly, the Company does not separately identify individual loans within this unit for impairment disclosures, unless such loans are subject to a troubled debt restructuring agreement.
	General component. The general component is based on historical loss experience adjusted for qualitative factors stratified by each of the loan segments: commercial and industrial, commercial real estate, construction, business banking commercial and industrial, business banking commercial real estate, residential real estate, home equity and consumer. Management uses an average of historical losses based on a time frame appropriate to capture relevant loss data for each loan class. This historical loss factor for each loan class is adjusted for the following qualitative factors: the levels/trends in delinquencies, classified and non-accruals; levels and trends in charge-offs and recoveries; trends in volume and terms of loans; effects of changes in risk selection and underwriting standards and other changes in lending policies, procedures and practices; experience, ability and depth of lending management and staff; national and local economic trends and industry conditions; and effects of changes in credit concentrations. This analysis establishes factors that are applied to each loan segment to determine the amount of the general component of the allowance for loan losses. In the second quarter of 2012, management made refinements to its allowance for loan loss methodology to create loss factors in connection with the establishment of the Business Banking unit. This refinement did not have a material effect on the loan loss provision or the total allowance for loan loss.
	Unallocated component. An unallocated component is maintained to cover uncertainties that could affect management’s estimate of probable losses. The unallocated component of the allowance reflects the margin of imprecision inherent in the underlying assumptions used in the methodologies for estimating allocated and general reserves in the portfolio.
	Reserve for unfunded commitments. The Company also maintains a reserve for unfunded credit commitments to provide for the risk of loss inherent in these arrangements. The reserve is determined using a methodology similar to the analysis of the allowance for loan losses, taking into consideration probabilities of future funding requirements. The reserve for unfunded commitments is included in other liabilities and was $213 and $89 at September 30, 2013 and 2012, respectively.
	Evaluation of the Investment Portfolio for Other-Than-Temporary Impairment. The evaluation of the investment portfolio for other-than-temporary impairment is also a critical accounting estimate. On a quarterly basis, management reviews securities with a decline in fair value below the amortized cost of the investment to determine whether the decline in fair value is temporary or other-than-temporary. Declines in the fair value of marketable equity securities below their cost that are deemed to be other-than-temporary based on the severity and duration of the impairment are reflected in earnings as realized losses. In estimating other-than-temporary impairment losses for securities, impairment is required to be recognized if (1) we intend to sell the security; (2) it is “more likely than not” that we will be required to sell the security before recovery of its amortized cost basis; or (3) the present value of expected cash flows is not sufficient to recover the entire amortized cost basis. For all impaired securities that management intends to sell, or more likely than not will be required to sell, the full amount of the other-than-temporary impairment is recognized through earnings. For all other impaired securities, credit-related other-than-temporary impairment is recognized through earnings, while non-credit related other-than-temporary impairment is recognized in other comprehensive income, net of applicable taxes.
	Income Taxes. The Company uses the asset and liability method of accounting for income taxes in which deferred tax assets and liabilities are established for the temporary differences between the financial reporting basis and the tax basis of the Company’s asset and liabilities. The realization of the net deferred tax asset generally depends upon future levels of taxable income and the existence of prior years’ taxable income, to which “carry back” refund claims could be made. A valuation allowance is maintained for deferred tax assets that management estimates are more likely than not to be unrealizable based on available evidence at the time the estimate is made. Significant management judgment is required in determining income tax expense and deferred tax assets and liabilities. In determining whether to establish a valuation allowance, the Company uses historical and forecasted future operating results, based upon approved business plans, including a review of the eligible carryforward periods, tax planning opportunities and other relevant considerations. These underlying assumptions can change from period to period. For example, tax law changes or variances in future projected operating performance could result in the establishment of or a change in the valuation allowance. Should actual factors and conditions differ materially from those considered by management, the actual realization of the net deferred tax asset could differ materially from the amounts recorded in the financial statements. If the Company is not able to realize all or part of its net deferred tax asset in the future, the establishment of or an adjustment to the deferred tax asset valuation allowance would be charged to income tax expense in the period such determination was made.
	Goodwill and Identifiable Intangible Assets. Goodwill and identifiable intangible assets are recorded as a result of business acquisitions and combinations. These assets are evaluated for impairment annually or whenever events or changes in circumstances indicate the carrying value of these assets may not be recoverable. If the carrying amount exceeds fair value, an impairment charge is recorded to income. The fair value is based on observable market prices, when practicable. Other valuation techniques may be used when market prices are unavailable, including estimated discounted cash flows and market multiples analyses. These types of analyses contain uncertainties because they require management to make assumptions and to apply judgment to estimate industry economic factors and the profitability of future business strategies. In the event of future changes in fair value, the Company may be exposed to an impairment charge that could be material.
	Valuation of Financial Instruments. The Company uses fair value measurements to record fair value adjustments to certain financial instruments and to determine fair value disclosures. Securities available for sale are recorded at fair value on a recurring basis. Additionally, from time to time, the Company may be required to record at fair value other assets on a non-recurring basis, or to establish a loss allowance or write-down based on the fair value of impaired assets. Further, the notes to the financial statements include information about the extent to which fair value is used to measure assets and liabilities, the valuation methodologies used and its impact to earnings. Additionally, for financial instruments not recorded at fair value, the notes to the financial statements disclose the estimate of their fair value. Due to the judgments and uncertainties involved in the estimation process, the estimates could result in materially different results under different assumptions and conditions.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	NOTE D – EARNINGS PER SHARE
	Earnings per share (“EPS”) has been computed by dividing net income by weighted average shares outstanding before any dilution and excluding the weighted average number of unallocated shares held by the Bank’s employee stock ownership plan (the “ESOP”). Diluted earnings per share has been calculated by dividing net income by weighted average shares outstanding after giving effect to the potential dilution that could occur if potential common shares were converted into common stock using the treasury stock method.
	The calculation of basic and diluted earnings per common share for the periods indicated is presented below.
			Three Months Ended				Nine Months Ended
			September 30,				September 30,
			2013		2012		2013		2012
	Net income		$	4,647	$	2,929	$	13,397	$	8,360
	Weighted average common shares applicable to basic EPS (1)			19,652,925		14,522,324		19,800,557		14,578,253
	Effect of dilutive potential common			319,877		186,049		278,308		249,175
	shares (2) (3)
	Weighted average common shares applicable to diluted EPS			19,972,802		14,708,373		20,078,865		14,827,428
	Earnings per share:
	Basic		$	0.24	$	0.2	$	0.68	$	0.57
	Diluted		$	0.23	$	0.2	$	0.67	$	0.56
	-1	Share-based compensation awards that qualify as participating securities (entiled to receive non-forfeitable dividends) are included in basic EPS.
	-2	Options to purchase 163,229 and 277,550 shares for the three months ended September 30, 2013 and 2012, respectively, and 197,628 and 197,300 shares for the nine months ended September 30, 2013 and 2012, respectively, were outstanding but not included in the computation of earnings per share because they were anti-dilutive.
	-3	Includes incremental shares related to dilutive stock options.

Accumulated_Other_Comprehensiv

Accumulated Other Comprehensive Income	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Accumulated Other Comprehensive Income	'
	NOTE E – ACCUMULATED OTHER COMPREHENSIVE INCOME
	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Although certain changes in assets and liabilities are reported as a separate component of the equity section of the statement of condition, such items are components of accumulated other comprehensive income.
	The components of accumulated other comprehensive income and related tax effects are as follows:
		September 30,			December 31,
		2013			2012
	Net unrealized gain on securities available for sale	$	2,503		$	10,147
	Tax effect		(923	)		(3,847	)
	Net-of-tax amount		1,580			6,300
	Pension liability		(1,432	)		(1,432	)
	Tax effect		533			533
	Net-of-tax amount		(899	)		(899	)
	Accumulated other comprehensive income	$	681		$	5,401

Investment_Securities

Investment Securities	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Investment Securities	'
	NOTE F – INVESTMENT SECURITIES
	The amortized cost and fair value of securities classified as available for sale and held to maturity are as follows:
		Amortized		Unrealized
		Cost		Gains			Losses			Fair Value
	Securities Available for Sale
	September 30, 2013:
	Debt Securities:
	Government-sponsored enterprises	$	2,099	$	—		$	(188	)	$	1,911
	Government-sponsored and government-guaranteed mortgage-backed securities		232,372		5,589			(2,567	)		235,394
	Private label mortgage-backed securities		8		—			—			8
	Municipal bonds		26,149		284			(1,203	)		25,230
	Corporate bonds		1,292		588			—			1,880
	Total	$	261,920	$	6,461		$	(3,958	)	$	264,423
	December 31, 2012:
	Debt Securities:
	Government-sponsored enterprises	$	3,234	$	2		$	(3	)	$	3,233
	Government-sponsored and government-guaranteed mortgage-backed securities		248,370		9,836			(444	)		257,762
	Private label mortgage-backed securities		2,568		54			(56	)		2,566
	Municipal bonds		28,713		595			(481	)		28,827
	Corporate bonds		1,290		644			—			1,934
	Total	$	284,175	$	11,131		$	(984	)	$	294,322
		Amortized		Unrealized
		Cost		Gains			Losses			Fair Value
	Securities Held to Maturity
	September 30, 2013:
	Government-sponsored and government-guaranteed mortgage-backed securities	$	73,432	$	1,535		$	(332	)	$	74,635
	Private label mortgage-backed securities		58		2			—			60
	Industrial revenue bonds		18,410		—			—			18,410
	State of Israel bonds		175		—			—			175
	Municipal bonds		5,916		197			—			6,113
	Total	$	97,991	$	1,734		$	(332	)	$	99,393
	December 31, 2012:
	Government-sponsored and government-guaranteed mortgage-backed securities	$	57,986	$	2,214		$	—		$	60,200
	Private label mortgage-backed securities		79		2			—			81
	Industrial revenue bonds		18,847		—			—			18,847
	State of Israel bonds		150		—			—			150
	Municipal bonds		5,924		472			—			6,396
	Total	$	82,986	$	2,688		$	—		$	85,674
	The scheduled maturities of debt securities available for sale and held to maturity at September 30, 2013 are shown below. Actual maturities will differ from contractual maturities because issuers generally have the right to call or prepay obligations with or without call or prepayment penalties.
		At September 30, 2013
		Securities					Securities
		Available for Sale					Held to Maturity
		Amortized					Amortized
		Cost		Fair Value			Cost			Fair Value
	Due in one year or less	$	—	$	—		$	125		$	125
	Due from one year to five years		2,278		2,338			810			845
	Due from five years to ten years		15,112		14,707			1,536			1,592
	Due after ten years		12,150		11,976			22,030			22,136
			29,540		29,021			24,501			24,698
	Mortgage-backed securities		232,380		235,402			73,490			74,695
		$	261,920	$	264,423		$	97,991		$	99,393
	Maturities are based on the final contractual payment dates, and do not reflect the impact of potential prepayments or early redemptions.
	The Company’s portfolio of mortgage-backed securities, which represent interests in pools of residential mortgage loans, consists primarily of securities issued by the Federal Home Loan Mortgage Corporation (Freddie Mac), the Federal National Mortgage Association (Fannie Mae), and the Government National Mortgage Association (Ginnie Mae), all of which are federal government owned or sponsored enterprises.
	Gross unrealized losses and fair values at September 30, 2013 and December 31, 2012 aggregated by investment category and the length of time that individual securities have been in a continuous unrealized loss position follow:
		Less than 12 months					12 months or longer						Total
		Fair		Unrealized			Fair			Unrealized			Number of		Fair		Unrealized
		Value		Losses			Value			Losses			Securities		Value		Losses
	At September 30, 2013:
	Securities Available for Sale
	Debt Securities:
	Government-sponsored enterprises	$	1,911	$	(188	)	$	—		$	—			5	$	1,911	$	(188	)
	Government-sponsored and government-guaranteed mortgage-backed securities		109,234		(2,331	)		11,354			(236	)		135		120,588		(2,567	)
	Municipal bonds		19,490		(1,203	)		—			—			47		19,490		(1,203	)
Total	$	130,635	$	(3,722	)	$	11,354		$	(236	)		187	$	141,989	$	(3,958	)
Securities Held to Maturity
Government-sponsored and government-guaranteed mortgage-backed securities	$	16,017	$	(332	)	$	—		$	—			3	$	16,017	$	(332	)
Total	$	16,017	$	(332	)	$	—		$	—			3	$	16,017	$	(332	)
	Less than 12 months					12 months or longer						Total
	Fair		Unrealized			Fair			Unrealized			Number of		Fair		Unrealized
	Value		Losses			Value			Losses			Securities		Value		Losses
At December 31, 2012:
Securities Available for Sale
Debt Securities:
Government-sponsored enterprises	$	1,998	$	(3	)	$	—		$	—			5	$	1,998	$	(3	)
Government-sponsored and government-guaranteed mortgage- backed securities		41,537		(444	)		—			—			81		41,537		(444	)
Private label mortgage-backed securities		1,671		(56	)		—			—			9		1,671		(56	)
Municipal bonds		16,293		(481	)		—			—			38		16,293		(481	)
Total	$	61,499	$	(984	)	$	—		$	—			133	$	61,499	$	(984	)
There were no securities classified as held to maturity in an unrealized loss position as of December 31, 2012.
Management evaluated the securities in the preceding tables and has determined that no declines in the fair value of the Company’s securities portfolio are deemed to be other-than-temporary as of September 30, 2013. In its evaluation, management considered the types of securities, including if the securities were U.S. Government issued, the credit rating on the securities, credit outlook, payment status and financial condition, the length of time the security has been in a loss position, the size of the loss position, intent and ability to hold the securities to expected recovery of value and other meaningful information. The Company does not intend to sell any impaired debt securities and is unlikely to be required to sell any impaired debt security before its maturity or market price recovery.

Loans

Loans	9 Months Ended
	Sep. 30, 2013
Receivables [Abstract]	'
Loans	'
	NOTE G – LOANS
	The components of the loan portfolio were as follows at September 30, 2013 and December 31, 2012:
		September 30,			December 31,
		2013			2012
	Commercial:
	Commercial and industrial	$	304,228		$	306,192
	Commercial real estate		872,340			814,692
	Construction		59,788			52,778
	Consumer:
	Residential real estate		459,714			441,874
	Home equity		179,507			179,039
	Consumer		17,920			21,501
	Total loans		1,893,497			1,816,076
	Net deferred loan costs and fees		2,653			3,414
	Allowance for loan losses		(13,642	)		(12,089	)
	Loans, net	$	1,882,508		$	1,807,401
	The Company transferred a portion of its originated commercial real estate and commercial and industrial loans to participating lenders. The amounts transferred have been accounted for as sales and are therefore not included in the Company’s accompanying consolidated statements of condition. The Company and participating lenders share ratably in any losses that may result from a borrower’s lack of compliance with contractual terms of the loan. The Company continues to service the loans on behalf of the participating lenders and, as such, collects cash payments from the borrowers, remits payments (net of servicing fees) to participating lenders and disburses required escrow funds to relevant parties. At September 30, 2013 and December 31, 2012, the Company was servicing loans for participants aggregating $72.0 million and $57.7 million, respectively.
	As of September 30, 2013 and December 31, 2012, the Company had two loans that were transferred to participants, which did not meet the requirements to be considered a participating interest. These transferred loans are reported as secured borrowings in the amount of $2.6 million and $2.4 million at September 30, 2013 and December 31, 2012, respectively, and are reported in long-term debt on the consolidated statement of condition.
	The Company established a Business Banking unit within its Commercial Lending Department during the second quarter of 2012. The portfolio is made up of both commercial and industrial and commercial real estate loans. As a result, the Company has reallocated charge-offs, recoveries, and allowance for loan losses accordingly. A summary of the activity pertaining to the allowance for loan losses for the three and nine months ended September 30, 2013 and 2012 is as follows:
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Three Months Ended September 30, 2013:
	Beginning balance	$	3,374		$	5,831		$	1,034		$	627		$	595		$	676		$	387		$	80		$	466		$	13,070
	Charge-offs		(326	)		(106	)		—			—			—			(113	)		(53	)		(2	)		—			(600	)
	Recoveries		7			27			—			—			—			—			1			12			—			47
	Provision (credit)		(155	)		1,064			(10	)		7			(6	)		183			50			(22	)		14			1,125
	Ending balance	$	2,900		$	6,816		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,642
											Business Banking
		Commercial									Commercial			Banking
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Three Months Ended September 30, 2012:
	Beginning balance	$	2,828		$	5,232		$	742		$	727		$	683		$	690		$	379		$	97		$	373		$	11,751
	Charge-offs		(109	)		(97	)		—			(40	)		(12	)		(45	)		(40	)		(10	)		—			(353	)
	Recoveries		84			10			—			1			—			—			—			7			—			102
	Provision (credit)		163			242			67			85			70			55			69			(7	)		306			1,050
	Ending balance	$	2,966		$	5,387		$	809		$	773		$	741		$	700		$	408		$	87		$	679		$	12,550
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Nine Months Ended September 30, 2013:
	Beginning balance	$	2,680		$	5,497		$	710		$	788		$	706		$	602		$	383		$	83		$	640		$	12,089
	Charge-offs		(758	)		(158	)		—			(123	)		(122	)		(188	)		(79	)		(67	)		—			(1,495	)
	Recoveries		24			27			—			—			—			1			2			27			—			81
	Provision (credit)		954			1,450			314			(31	)		5			331			79			25			(160	)		2,967
	Ending balance	$	2,900		$	6,816		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,642
											Business Banking
		Commercial									Commercial			Banking
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Nine Months Ended September 30, 2012:
	Beginning balance	$	3,446		$	5,572		$	860		$	—		$	—		$	666		$	474		$	114		$	—		$	11,132
	Charge-offs		(315	)		(370	)		(127	)		(128	)		(52	)		(133	)		(70	)		(15	)		—			(1,210	)
	Recoveries		123			45			1			2			—			—			—			7			—			178
	Provision (credit)		(288	)		140			75			899			793			167			4			(19	)		679			2,450
	Ending balance	$	2,966		$	5,387		$	809		$	773		$	741		$	700		$	408		$	87		$	679		$	12,550
	Further information pertaining to the allowance for loan losses at September 30, 2013 and December 31, 2012 is as follows:
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
	Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
At September 30, 2013:
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	$	30		$	400		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	430
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	$	2,870		$	6,416		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,212
Total loans	$	272,989		$	792,503		$	59,788		$	31,239		$	79,837		$	459,714		$	179,507		$	17,920		$	—		$	1,893,497
Loans deemed to be impaired and individually evaluated for impairment	$	5,112		$	2,364		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	7,476
Loans not deemed to be impaired and collectively evaluated for impairment	$	267,617		$	788,198		$	59,788		$	31,239		$	79,837		$	459,714		$	179,507		$	17,920		$	—		$	1,883,820
Loans acquired with deteriorated credit quality and deemed to be impaired	$	260		$	1,941		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	2,201
										Business Banking
	Commercial									Commercial
	and			Commercial						and			Commercial						Home
	Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
At December 31, 2012:
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	$	32		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	32
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	$	2,648		$	5,497		$	710		$	788		$	706		$	602		$	383		$	83		$	640		$	12,057
Total loans	$	272,789		$	732,272		$	52,778		$	33,403		$	82,420		$	441,874		$	179,039		$	21,501		$	—		$	1,816,076
Loans deemed to be impaired and individually evaluated for impairment	$	5,943		$	3,882		$	591		$	—		$	—		$	—		$	—		$	—		$	—		$	10,416
Loans not deemed to be impaired and collectively evaluated for impairment	$	266,091		$	722,470		$	51,838		$	33,403		$	82,420		$	441,874		$	179,039		$	21,501		$	—		$	1,798,636
Loans acquired with deteriorated credit quality and deemed to be impaired	$	755		$	5,920		$	349		$	—		$	—		$	—		$	—		$	—		$	—		$	7,024
The following is a summary of past due loans at September 30, 2013 and December 31, 2012:
																			Recorded
							90 Days									Total			Investments
	30-59 Days			60-89 Days			and Over			Total						Financing			> 90 Days
	Past Due			Past Due			Past Due			Past Due			Current			Receivables			and Accruing
At September 30, 2013:
Commercial:
Commercial and industrial	$	1,603		$	21		$	2,990		$	4,614		$	299,614		$	304,228		$	—
Commercial real estate		3,633			4,873			3,462			11,968			860,372			872,340			—
Construction		—			280			—			280			59,508			59,788			—
Consumer:
Residential real estate		—			1,786			4,224			6,010			453,704			459,714			—
Home equity		392			190			941			1,523			177,984			179,507			—
Consumer		323			—			117			440			17,480			17,920			—
Total	$	5,951		$	7,150		$	11,734		$	24,835		$	1,868,662		$	1,893,497		$	—
At December 31, 2012:
Commercial:
Commercial and industrial	$	3,974		$	1,155		$	4,442		$	9,571		$	296,621		$	306,192		$	—
Commercial real estate		6,326			1,136			5,351			12,813			801,879			814,692			—
Construction		2,853			—			—			2,853			49,925			52,778			—
Consumer:
Residential real estate		11,760			2,450			2,615			16,825			425,049			441,874			—
Home equity		1,044			161			137			1,342			177,697			179,039			—
Consumer		329			35			120			484			21,017			21,501			—
Total	$	26,286		$	4,937		$	12,665		$	43,888		$	1,772,188		$	1,816,076		$	—
The following is a summary of impaired loans at September 30, 2013 and December 31, 2012:
	At September 30, 2013									At December 31, 2012
				Unpaid									Unpaid
	Recorded			Principal			Related			Recorded			Principal			Related
	Investment			Balance			Allowance			Investment			Balance			Allowance
With no related allowance recorded:
Commercial and industrial	$	4,452		$	4,473					$	6,666		$	6,997
Commercial real estate		3,682			4,182						9,802			10,736
Construction		—			—						940			940
Total	$	8,134		$	8,655					$	17,408		$	18,673
With an allowance recorded:
Commercial and industrial		920			920		$	30			32			32		$	32
Commercial real estate		623			623			400			—			—			—
Total	$	1,543		$	1,543		$	430		$	32		$	32		$	32
Total impaired loans	$	9,677		$	10,198		$	430		$	17,440		$	18,705		$	32
The following is a summary of information pertaining to impaired loans:
	Three Months Ended September 30, 2013									Three Months Ended September 30, 2012
	Average			Interest Income						Average			Interest Income
	Recorded						Recognized			Recorded						Recognized
	Investment on						on a			Investment on						on a
	Impaired Loans			Recognized			Cash Basis			Impaired Loans			Recognized			Cash Basis
Commercial:
Commercial and industrial	$	5,922		$	40		$	—		$	4,396		$	1		$	—
Commercial real estate		5,907			19			—			3,378			10			—
Construction		144			—			—			617			6			—
Consumer:
Residential real estate		—			23			23			—			—			—
Consumer		—			—			—			—			1			1
Total	$	11,973		$	82		$	23		$	8,391		$	18		$	1
	Nine Months Ended September 30, 2013									Nine Months Ended September 30, 2012
	Average			Interest Income						Average			Interest Income
	Recorded						Recognized			Recorded						Recognized
	Investment on						on a			Investment on						on a
	Impaired Loans			Recognized			Cash Basis			Impaired Loans			Recognized			Cash Basis
Commercial:
Commercial and industrial	$	6,268		$	454		$	329		$	4,320		$	10		$	8
Commercial real estate		6,724			52			10			3,477			35			7
Construction		850			5			—			708			19			—
Consumer:
Residential real estate		—			39			39			—			2			2
Consumer		—			—			—			—			1			1
Total	$	13,842		$	550		$	378		$	8,505		$	67		$	18
The following is a summary of non-accrual loans, at September 30, 2013 and December 31, 2012:
	September 30,			December 31,
	2013			2012
Commercial:
Commercial and industrial	$	3,510		$	5,538
Commercial real estate		3,462			5,596
Construction		—			349
Consumer:
Residential real estate		4,256			2,970
Home equity		941			137
Consumer		117			120
Total	$	12,286		$	14,710
The following table represents modifications that were deemed to be troubled debt restructurings for the nine months ended September 30, 2013 and 2012:
	Nine Months Ended September 30, 2013									Nine Months Ended September 30, 2012
	Number of			Outstanding Recorded Investment						Number of			Outstanding Recorded Investment
	Contracts			Pre-Modification			Post-Modification			Contracts			Pre-Modification			Post-Modification
Troubled Debt
Restructurings:
Commercial and industrial		2		$	1,824		$	1,420			1		$	140		$	140
Commercial real estate		—			—			—			4			1,211			1,211
Construction		—			—			—			2			613			613
Total		2		$	1,824		$	1,420			7		$	1,964		$	1,964
There were no loan modifications that were deemed troubled debt restructurings for the three months ended September 30, 2013 and 2012.
At September 30, 2013, the modifications related to two commercial and industrial loans to one borrower that were restructured as part of an agreement with the customer whereby the Bank received a cash paydown. The modifications lowered the interest rate and extended the maturity of these loans.
At September 30, 2012, the modifications provided on one commercial and industrial loan and four commercial real estate loans are related to one borrower relationship. The modification extended the maturity of demand notes that had reached maturity. The modifications provided on the two construction loans are related to one borrower relationship. The modification extended the maturity of demand notes that had reached maturity. Management performs a discounted cash flow calculation or collateral analysis if the loan is collateral dependent to determine the amount of impaired reserve required on each of the troubled debt restructurings. Any reserve required is recorded through the provision for loan losses.
As of September 30, 2013 and 2012, there have been no TDRs that have subsequently defaulted (defined as thirty or more days past due) within one year of modification.
CREDIT QUALITY INFORMATION
The Company utilizes a nine grade risk rating system for commercial and industrial, commercial real estate and construction loans as follows:
Pass: Loans within these five categories are considered low to average risk.
Special Mention: Loans in this category portray one or more weaknesses that may be tolerated in the short run. Assets in this category are currently protected but are potentially weak and are being closely monitored by management.
Substandard: Loans in this category are considered inadequately protected by the current sound worth and paying capacity of the obligor or of the collateral pledged. There is a distinct possibility that the Company will sustain some loss if the weakness is not corrected.
Doubtful: Loans in this category have all the weaknesses inherent in those classified substandard with the added characteristic that the weaknesses make the collection or liquidation in full, on the basis of currently existing facts, conditions and values, highly questionable and improbable. The possibility of loss is extremely high, however, its classification as an estimated loss is deferred until a more exact determination of the extent of the loss is ascertained.
Loss: Loans in this category are considered uncollectible and of such little value that their continuance as loans is not warranted.
The Company does not assign risk ratings to residential real estate, home equity and consumer loans unless they are contractually past due 90 days or more or where legal action has commenced against the borrower. All other consumer loans are charged off when they become contractually past due 120 days. Loans not assigned a rating are considered “pass.”
Business banking loans are assigned a Pass rating unless they are contractually past due 90 days or more, legal action has commenced against the borrower or other criteria for a risk rating change as defined within the business banking loan policy have been triggered. Upon one or more of these events, the loan will be risk rated Substandard.
On an annual basis, or more often if needed, the Company formally reviews the ratings on all commercial and industrial, commercial real estate and construction loans. Semi-annually, the Company engages an independent third party to review loans within these segments. Management uses the results of these reviews as part of its annual review process.
The following tables present the Company’s loan segment by internally assigned grades:
	At September 30, 2013
	Commercial			Commercial
	and Industrial			Real Estate			Construction			Total
Commercial:
Grade:
Pass	$	276,722		$	817,581		$	55,842		$	1,150,145
Special Mention		9,292			27,332			428			37,052
Substandard		17,551			27,427			3,518			48,496
Doubtful		663			—			—			663
Total	$	304,228		$	872,340		$	59,788		$	1,236,356
	Residential			Home Equity			Consumer			Total
Consumer:
Grade:
Pass	$	455,676		$	178,693		$	17,894		$	652,263
Special Mention		—			—			—			—
Substandard		4,038			814			26			4,878
Doubtful		—			—			—			—
Total	$	459,714		$	179,507		$	17,920		$	657,141
	At December 31, 2012
	Commercial			Commercial
	and Industrial			Real Estate			Construction			Total
Commercial:
Grade:
Pass	$	275,279		$	762,240		$	46,196		$	1,083,715
Special Mention		14,788			29,092			1,632			45,512
Substandard		15,472			23,360			4,950			43,782
Doubtful		653			—			—			653
Total	$	306,192		$	814,692		$	52,778		$	1,173,662
	Residential			Home Equity			Consumer			Total
Consumer:
Grade:
Pass	$	439,201		$	178,920		$	21,382		$	639,503
Special Mention		—			—			—			—
Substandard		2,673			119			119			2,911
Doubtful		—			—			—			—
Total	$	441,874		$	179,039		$	21,501		$	642,414

Commitments

Commitments	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments	'
	NOTE H – COMMITMENTS
	Financial instruments with off-balance sheet risk at September 30, 2013 and December 31, 2012 were as follows:
		September 30,		December 31,
		2013		2012
	Unused lines of credit	$	338,049	$	308,683
	Amounts due mortgagors		100,533		36,365
	Standby letters of credit		5,499		3,573
	Commitments to originate loans		22,851		63,974
	The Company has also committed to invest up to $10.0 million, representing 25% of the Class A or senior investor balance, in low income housing tax credit funds by the end of 2015. At September 30, 2013, the Company invested $8.4 million in the funds, which has been reduced by net operating losses of $2.0 million. The net carrying balance of $6.4 million is included in other assets on the Company’s consolidated statement of condition. As a Class A investor, the Company has the right to transfer its investment to the fund’s Class B investor at the end of 10 years at which time the Company would have no compliance requirements or interest in the fund. The fund structure contemplates that the Class A investors will receive 95% of the tax credits and net operating losses for a period of eight years or until the minimum investment return has been met. Net operating losses allocated to the Company are recognized as they are incurred and recorded in non-interest expense.
	In 2012, the Company committed to and invested $1.8 million, or 50% interest, in a new markets housing tax credit fund, which has been reduced by net operating losses of $33. The net carrying value of $1.8 million is included in other assets on the Company’s consolidated statement of condition.
	The Company has committed to invest $2.0 million in another low income housing tax credit fund by the end of 2015. At September 30, 2013, the Company invested $1.1 million in this fund, which has been reduced by net operating losses of $165. The net carrying value of $972 is included in other assets on the Company’s consolidated statement of condition.
	The Company committed to and invested $979 in another new market tax credit fund in August 2013. The net carrying value of $979 is included in other assets on the Company’s consolidated financial statement of condition.

Deposits

Deposits	9 Months Ended
	Sep. 30, 2013
Banking And Thrift [Abstract]	'
Deposits	'
	NOTE I – DEPOSITS
	Deposit accounts, by type, are summarized as follows at September 30, 2013 and December 31, 2012:
		September 30,		December 31,
		2013		2012
	Demand	$	333,206	$	307,302
	NOW		86,545		87,983
	Savings		335,623		350,188
	Money market		455,547		395,293
	Certificates of deposit		735,477		707,409
		$	1,946,398	$	1,848,175

Contingencies

Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Contingencies	'
	NOTE J – CONTINGENCIES
	The Bank, as successor in interest to Commonwealth National Bank, is involved in litigation relating to a loan foreclosure. The litigants claim that Commonwealth National Bank acted in bad faith and in violation of applicable law and that its actions resulted in a sale of the underlying property for less than its market value, thereby causing damage to the parties. During the third quarter of 2011, the judge issued a ruling in favor of the Bank. The litigants have appealed the decision. The Bank believes these claims and the appeal are without merit and is vigorously defending the litigation. No estimate of any reasonably possible loss or range of loss to the Bank can be made at this time.
	The Bank is also a defendant in other claims and legal actions arising in the ordinary course of business. In the opinion of management, after consultation with legal counsel, the ultimate disposition of these matters is not expected to have a material adverse effect on the Company’s financial condition, results of operations or cash flows.

Fair_Values_of_Assets_and_Liab

Fair Values of Assets and Liabilities	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Fair Values of Assets and Liabilities	'
	NOTE K – FAIR VALUES OF ASSETS AND LIABILITIES
	The Company groups its assets measured at fair value in three levels, based on the markets in which the assets are traded and the reliability of the assumptions used to determine fair value, as follows:
	Level 1 – Valuations for assets traded in active exchange markets, such as the New York Stock Exchange. Level 1 also includes U.S. Treasury, other U.S. government and government-sponsored enterprises that are traded by dealers or brokers in active markets. Valuations are obtained from readily available pricing sources for market transactions involving identical assets.
	Level 2 – Valuations for assets traded in less active dealer or broker markets. Level 2 includes U.S. government and mortgage-backed securities issued by government-sponsored enterprises. Valuations are obtained from third party pricing services for identical or comparable assets.
	Level 3 – Valuations for assets that are derived from other valuation methodologies, including option pricing models, discounted cash flow models and similar techniques, and not based on market exchange, dealer, or broker-traded transactions. Level 3 valuations incorporate certain assumptions and projections in determining the fair value assigned to such assets and liabilities. Level 3 also includes corporate bonds that have fair values derived from unobservable issuer-provided financial information and discounted cash flow models.
	Assets measured at fair value on a recurring basis, are summarized below:
									Total
		Level 1			Level 2		Level 3		Fair Value
	At September 30, 2013
	Securities available for sale:
	Government-sponsored enterprises	$	—		$	1,911	$	—	$	1,911
	Government-sponsored and government-guaranteed mortgage-backed securities		—			235,394		—		235,394
	Private label mortgage-backed securities		—			8		—		8
	Municipal bonds		—			25,230		—		25,230
	Corporate bonds		—			—		1,880		1,880
	Total	$	—		$	262,543	$	1,880	$	264,423
									Total
		Level 1			Level 2		Level 3		Fair Value
	At December 31, 2012
	Securities available for sale:
	Government-sponsored enterprises	$	—		$	3,233	$	—	$	3,233
	Government-sponsored and government-guaranteed mortgage-backed securities		—			257,762		—		257,762
	Private label mortgage-backed securities		—			2,566		—		2,566
	Municipal bonds		—			28,827		—		28,827
	Corporate bonds		—			—		1,934		1,934
	Total	$	—		$	292,388	$	1,934	$	294,322
	The Company had no liabilities measured at fair value on a recurring basis at September 30, 2013 or December 31, 2012.
	The table below presents the changes in Level 3 assets measured at fair value on a recurring basis for the nine months ended September 30, 2013.
	Balance at December 31, 2012	$	1,934
	Change in unrealized gain		(54	)
	Balance at September 30, 2013	$	1,880
	Due to the lack of observable market data, corporate bonds were included in Level 3 of the fair value hierarchy. The fair value has been derived by third party pricing services using pricing models and techniques which require significant judgment and estimation. Pricing models and techniques are dependent upon several unobservable inputs including the discount rate, the interest rate environment, credit defaults and losses and financial performance.
	There were no transfers in or out of levels 1 and 2.
	The Company may be required, from time to time, to measure at fair value certain other assets on a nonrecurring basis in accordance with GAAP. These adjustments to fair value usually result from application of lower-of-cost-or-fair value accounting or write-downs of individual assets. The following tables summarize the fair value hierarchy used to determine the adjustment and the carrying value of the related individual assets for the three and nine months ended September 30, 2013 and 2012.
									Three Months Ended			Nine Months Ended
									September 30, 2013			September 30, 2013
		At September 30, 2013							Total			Total
		Level 1			Level 2		Level 3		Gains/(Losses)			Gains/(Losses)
	Assets:
	Loans	$	—		$	—	$	714	$	57		$	(565	)
	Other real estate owned		—			—		711		—			(135	)
	Total assets	$	—		$	—	$	1,425	$	57		$	(700	)
									Three Months Ended			Nine Months Ended
									September 30, 2012			September 30, 2012
		At September 30, 2012							Total			Total
		Level 1			Level 2		Level 3		Gains/(Losses)			Gains/(Losses)
	Assets:
	Loans	$	—		$	—	$	722	$	(116	)	$	(126	)
	Other real estate owned		—			—		1,070		(134	)		(184	)
	Other assets		—			—		595		(37	)		(37	)
	Total assets	$	—		$	—	$	2,387	$	(287	)	$	(347	)
	The amount of loans represents the carrying value of impaired loans net of related write-downs and valuation allowances for which adjustments are based on the estimated fair value of the underlying collateral. The other real estate owned amount represents the carrying value for which adjustments are also based on the estimated fair value of the property.
	Fair value estimates are made at a specific point in time, based on relevant market information and information about the financial instrument. 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. Because a market may not readily exist for a significant portion of the Company’s financial instruments, fair value estimates are 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.
	The following methods and assumptions were used by the Company in estimating fair values of its financial instruments:
	Cash and Cash Equivalents and Short-term Investments. The carrying amounts of cash and short-term instruments approximate fair values based on the short-term nature of the assets.
	Investment Securities and FHLBB Stock. The fair value of securities to be held to maturity and securities available for sale is estimated based on quoted market prices, where available. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments. Ownership of Federal Home Loan Bank of Boston (“FHLBB”) stock is restricted to member banks; therefore, the stock is not traded. The estimated fair value of FHLBB stock is equal to its carrying value, which represents the price at which the FHLBB is obligated to redeem its stock.
	Loans. For valuation purposes, the loan portfolio was segregated into its significant categories, which are residential mortgage, commercial real estate, commercial and industrial, construction and consumer loans. These categories were further segregated, where appropriate, into components based on significant financial characteristics such as type of interest rate (fixed or adjustable). Fair values were estimated for each component using assumptions developed by management and a valuation model provided by a third party specialist.
	The fair values of residential mortgage, commercial real estate, commercial and industrial, construction and consumer loans were estimated by discounting the anticipated cash flows from the respective portfolios. Estimates of the timing and amount of these cash flows considered factors such as future loan prepayments. The discount rates reflected current market rates for loans with similar terms to borrowers of similar credit quality. The fair value of home equity lines of credit was based on the outstanding loan balances. Fair values for non-performing loans are estimated using discounted cash flow analyses or underlying collateral values, where applicable.
	Loans Held for Sale. Fair values are based on commitments in effect from investors or prevailing market rates.
	Deposits. The fair value of deposits with no stated maturity, such as demand deposits, NOW, regular savings, and money market deposit accounts, is equal to the amount payable on demand. The fair value estimates do not include the benefit that results from the generally lower cost of funding provided by the deposit liabilities compared to the cost of borrowing funds in the market. The fair value estimate of time deposits is based on the discounted value of contractual cash flows. The discount rate is estimated using the rates currently offered for deposits having similar remaining maturities.
	Short-term Borrowings. For short-term borrowings maturing within one year, carrying values approximate fair values. Fair values of other short-term borrowings are estimated using discounted cash flow analyses based on the current incremental borrowing rates in the market for similar types of borrowing arrangements.
	Long-term Debt. The fair values of the Company’s long-term debt are estimated using discounted cash flow analyses based on the current incremental borrowing rates in the market for similar types of borrowing arrangements.
	Repurchase Agreements. The Company enters into overnight repurchase agreements with its customers. Since these agreements are short-term instruments, the fair value of these agreements approximates their recorded balance. The Company also secures term repurchase agreements through other financial institutions. The fair value of these agreements are determined by discounting the anticipated future cash payments using rates currently available to the Bank for debt with similar terms and remaining maturities.
Subordinated Debentures. The Company has outstanding subordinated debt in the form of trust preferred securities issued through a private placement offering. The fair value estimate is determined by discounting the anticipated future cash payments by using the rates currently available to the Company for debt with similar terms and remaining maturities.
Off-Balance Sheet Instruments. The fair value of off-balance-sheet mortgage lending commitments are based on fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the counterparties’ credit standing. In the case of the commitments discussed in Note H, the fair value equals the carrying amounts which are not significant.
Summary of Fair Values of Financial Instruments. The estimated fair values, and related carrying or notional amounts, of the Company’s financial instruments are as follows. Certain financial instruments and all nonfinancial instruments are exempt from disclosure requirements. Accordingly, the aggregate fair value amounts presented herein do not represent the underlying fair value of the Company.
The fair value of the Company’s financial instruments is as follows at dates indicated:
	At September 30, 2013
	Carrying										Estimated
	Value			Level 1		Level 2		Level 3			Fair Value
Financial Assets:
Cash and cash equivalents	$	58,960		$	58,960	$	—	$	—		$	58,960
Securities available for sale		264,423			—		262,543		1,880			264,423
Securities held to maturity		97,991			—		99,393		—			99,393
Stock in Federal Home Loan Bank of Boston		17,334			—		—		17,334			17,334
Net loans and loans held for sale		1,882,508			—		—		1,887,816			1,887,816
Financial Liabilities:
Deposits (with no stated maturity)		1,210,921			—		—		1,210,921			1,210,921
Time deposits		735,477			—		—		740,330			740,330
Federal Home Loan Bank of Boston advances		151,029			—		—		153,706			153,706
Repurchase agreements		60,446			—		—		60,967			60,967
Subordinated debentures		5,933			—		5,933		—			5,933
	At December 31, 2012
	Carrying										Estimated
	Value			Level 1		Level 2		Level 3			Fair Value
Financial Assets:
Cash and cash equivalents	$	30,679		$	30,679	$	—	$	—		$	30,679
Securities available for sale		294,322			—		292,388		1,934			294,322
Securities held to maturity		82,986			—		85,674		—			85,674
Stock in Federal Home Loan Bank of Boston		18,554			—		—		18,554			18,554
Net loans and loans held for sale		1,808,033			—		—		1,846,519			1,846,519
Financial Liabilities:
Deposits (with no stated maturity)		1,140,766			—		—		1,140,766			1,140,766
Time deposits		707,409			—		—		711,845			711,845
Federal Home Loan Bank of Boston advances		141,525			—		—		145,543			145,543
Repurchase agreements		69,229			—		—		70,082			70,082
Subordinated debentures		9,630			—		9,630		—			9,630

Pension_and_Postretirement_Ben

Pension and Postretirement Benefit Plans	9 Months Ended
	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]	'
Pension and Postretirement Benefit Plans	'
	NOTE L – PENSION AND POSTRETIREMENT BENEFIT PLANS
	The Company maintains a Senior Executive Retirement Plan (“SERP”) and a Director Retirement Plan. These plans had no assets at September 30, 2013 and 2012. The following table presents the components of the net periodic benefit cost for the indicated periods:
		For the Three Months Ended September 30,								For the Nine Months Ended September 30,
		2013				2012				2013				2012
				Director				Director				Director				Director
				Retirement				Retirement				Retirement				Retirement
		SERP		Plan		SERP		Plan		SERP		Plan		SERP		Plan
	Periodic benefit cost:
	Service cost	$	101	$	14	$	78	$	24	$	301	$	41	$	236	$	70
	Interest cost		47		11		44		14		141		33		132		42
	Total pension cost		148		25		122		38		442		74		368		112
	Prior service cost amortization		50		10		29		9		150		32		86		27
	Net loss amortization		—		12		—		2		—		36		—		8
	Net periodic benefit cost	$	198	$	47	$	151	$	49	$	592	$	142	$	454	$	147
	Benefits expected to be paid over the next five years as presented in the Company’s Annual Report on Form 10-K for the year ended December 31, 2012 have not changed. These plans are funded on a pay-as-you-go-basis and the Company does not expect to make any contributions to these plans in 2013.

Recent_Accounting_Pronouncemen1

Recent Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Fair Value Measurement	'
	In October 2012, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2012-04, Technical Amendments and Corrections to SEC Sections 2011-08. This ASU is intended to clarify the FASB Accounting Standards Codification (“Codification”), correct unintended application of guidance and includes amendments identifying when the use of fair value should be linked to the definition of fair value in Topic 820, Fair Value Measurement. Amendments to the Codification without transition guidance are effective upon issuance for both public and non-public entities. This ASU was adopted in the first quarter of 2013 and did not have a material impact on the Company’s consolidated financial statements.
Comprehensive Income	'
	In February 2013, the FASB issued ASU 2013-02, Comprehensive Income (Topic 220): Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income. This Update requires entities to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, entities are required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line item of net income. The Company adopted this ASU in the first quarter of 2013 and there was no impact on the Company’s consolidated financial results as the amendments relate only to disclosures in the consolidated financial statements.
Unrecognized Tax Benefit	'
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force). This Update provides that an unrecognized tax benefit, or a portion thereof, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward, except to the extent that a net operating loss carryforward, a similar tax loss, or a tax credit carryforward is not available at the reporting date to settle any additional income taxes that would result from disallowance of a tax position, or the tax law does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, then the unrecognized tax benefit should be presented as a liability. This ASU is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The Company does not expect that the adoption of this ASU will have an impact on the Company’s consolidated financial statements.
Allowance for Loan Losses	'
	Allowance for Loan Losses. The allowance for loan losses is the amount estimated by management as necessary to cover credit losses inherent in the loan portfolio at the balance sheet date. The allowance is established through the provision for loan losses which is charged against income. The methodology for determining the allowance for loan losses is considered a critical accounting policy by management due to the high degree of judgment involved, the subjectivity of the assumptions utilized and the potential for changes in the economic environment that could result in adjustments to the amount of the recorded allowance for loan losses.
	Management performs a quarterly evaluation of the adequacy of the allowance for loan losses. We consider a variety of factors in establishing this estimate including, but not limited to, prior loss experience, current economic conditions, trends in non-performing, classified and impaired loans, charge-offs and delinquency rates, the adequacy of the underlying collateral, the size and composition of the loan portfolio, the financial strength of the borrower, results of internal loan reviews and other relevant factors. This evaluation is inherently subjective as it requires material estimates by management that may be susceptible to significant change based on changes in economic and real estate market conditions.
	A loan is considered impaired when, based on current information and events, it is probable that the Company will be unable to collect the scheduled payments of principal or interest when due according to the contractual terms of the loan agreement. Factors considered by management in determining impairment include payment status, collateral value, and the probability of collecting scheduled principal and interest payments when due. Loans that experience insignificant payment delays and payment shortfalls generally are not classified as impaired.
	The Company periodically may agree to modify the contractual terms of loans. A loan is classified as a troubled debt restructuring (“TDR”) if the Company grants a concession to a borrower that is experiencing financial difficulties. This usually includes a modification of loan terms, such as a reduction of the interest rate to below market terms, capitalizing past due interest, extending the maturity date or a partial forgiveness of debt. A TDR loan is returned to accrual status after the borrower demonstrates the ability to pay under the restructured terms through a sustained period of repayment performance, which is generally six months. All TDRs are classified as impaired.
	The allowance consists of a specific, general, and unallocated component, as further described below.
Specific Component	'
	Specific component. The specific component relates to loans that are classified as impaired. Impairment is measured on a loan by loan basis for the commercial segments (commercial and industrial, commercial real estate and construction) by either the present value of expected future cash flows discounted at the loan’s effective interest rate or the fair value of the collateral if the loan is collateral dependent. A specific allowance is established when the discounted cash flows (or collateral value) of the impaired loan is lower than the carrying value of the loan. Groups of smaller balance homogenous loans are collectively evaluated for impairment. Accordingly, the Company does not separately identify individual loans in the consumer segments (residential real estate, home equity and consumer loans) for impairment disclosures, unless such loans are subject to a troubled debt restructuring agreement.
	The Company has established a Business Banking unit within its Commercial Lending Department. The portfolio is made up of both commercial and industrial loans less than $250 and commercial real estate loans less than $500 which are managed by exception. This grouping of loans is considered a homogenous pool of loans and collectively evaluated for impairment. Accordingly, the Company does not separately identify individual loans within this unit for impairment disclosures, unless such loans are subject to a troubled debt restructuring agreement.
General Component	'
	General component. The general component is based on historical loss experience adjusted for qualitative factors stratified by each of the loan segments: commercial and industrial, commercial real estate, construction, business banking commercial and industrial, business banking commercial real estate, residential real estate, home equity and consumer. Management uses an average of historical losses based on a time frame appropriate to capture relevant loss data for each loan class. This historical loss factor for each loan class is adjusted for the following qualitative factors: the levels/trends in delinquencies, classified and non-accruals; levels and trends in charge-offs and recoveries; trends in volume and terms of loans; effects of changes in risk selection and underwriting standards and other changes in lending policies, procedures and practices; experience, ability and depth of lending management and staff; national and local economic trends and industry conditions; and effects of changes in credit concentrations. This analysis establishes factors that are applied to each loan segment to determine the amount of the general component of the allowance for loan losses. In the second quarter of 2012, management made refinements to its allowance for loan loss methodology to create loss factors in connection with the establishment of the Business Banking unit. This refinement did not have a material effect on the loan loss provision or the total allowance for loan loss.
Unallocated Component	'
	Unallocated component. An unallocated component is maintained to cover uncertainties that could affect management’s estimate of probable losses. The unallocated component of the allowance reflects the margin of imprecision inherent in the underlying assumptions used in the methodologies for estimating allocated and general reserves in the portfolio.
Reserve for Unfunded Commitments	'
	Reserve for unfunded commitments. The Company also maintains a reserve for unfunded credit commitments to provide for the risk of loss inherent in these arrangements. The reserve is determined using a methodology similar to the analysis of the allowance for loan losses, taking into consideration probabilities of future funding requirements. The reserve for unfunded commitments is included in other liabilities and was $213 and $89 at September 30, 2013 and 2012, respectively.
Evaluation of the Investment Portfolio for Other-Than-Temporary Impairment	'
	Evaluation of the Investment Portfolio for Other-Than-Temporary Impairment. The evaluation of the investment portfolio for other-than-temporary impairment is also a critical accounting estimate. On a quarterly basis, management reviews securities with a decline in fair value below the amortized cost of the investment to determine whether the decline in fair value is temporary or other-than-temporary. Declines in the fair value of marketable equity securities below their cost that are deemed to be other-than-temporary based on the severity and duration of the impairment are reflected in earnings as realized losses. In estimating other-than-temporary impairment losses for securities, impairment is required to be recognized if (1) we intend to sell the security; (2) it is “more likely than not” that we will be required to sell the security before recovery of its amortized cost basis; or (3) the present value of expected cash flows is not sufficient to recover the entire amortized cost basis. For all impaired securities that management intends to sell, or more likely than not will be required to sell, the full amount of the other-than-temporary impairment is recognized through earnings. For all other impaired securities, credit-related other-than-temporary impairment is recognized through earnings, while non-credit related other-than-temporary impairment is recognized in other comprehensive income, net of applicable taxes.
Income Taxes	'
	Income Taxes. The Company uses the asset and liability method of accounting for income taxes in which deferred tax assets and liabilities are established for the temporary differences between the financial reporting basis and the tax basis of the Company’s asset and liabilities. The realization of the net deferred tax asset generally depends upon future levels of taxable income and the existence of prior years’ taxable income, to which “carry back” refund claims could be made. A valuation allowance is maintained for deferred tax assets that management estimates are more likely than not to be unrealizable based on available evidence at the time the estimate is made. Significant management judgment is required in determining income tax expense and deferred tax assets and liabilities. In determining whether to establish a valuation allowance, the Company uses historical and forecasted future operating results, based upon approved business plans, including a review of the eligible carryforward periods, tax planning opportunities and other relevant considerations. These underlying assumptions can change from period to period. For example, tax law changes or variances in future projected operating performance could result in the establishment of or a change in the valuation allowance. Should actual factors and conditions differ materially from those considered by management, the actual realization of the net deferred tax asset could differ materially from the amounts recorded in the financial statements. If the Company is not able to realize all or part of its net deferred tax asset in the future, the establishment of or an adjustment to the deferred tax asset valuation allowance would be charged to income tax expense in the period such determination was made.
Goodwill and Identifiable Intangible Assets	'
	Goodwill and Identifiable Intangible Assets. Goodwill and identifiable intangible assets are recorded as a result of business acquisitions and combinations. These assets are evaluated for impairment annually or whenever events or changes in circumstances indicate the carrying value of these assets may not be recoverable. If the carrying amount exceeds fair value, an impairment charge is recorded to income. The fair value is based on observable market prices, when practicable. Other valuation techniques may be used when market prices are unavailable, including estimated discounted cash flows and market multiples analyses. These types of analyses contain uncertainties because they require management to make assumptions and to apply judgment to estimate industry economic factors and the profitability of future business strategies. In the event of future changes in fair value, the Company may be exposed to an impairment charge that could be material.
Valuation of Financial Instruments	'
	Valuation of Financial Instruments. The Company uses fair value measurements to record fair value adjustments to certain financial instruments and to determine fair value disclosures. Securities available for sale are recorded at fair value on a recurring basis. Additionally, from time to time, the Company may be required to record at fair value other assets on a non-recurring basis, or to establish a loss allowance or write-down based on the fair value of impaired assets. Further, the notes to the financial statements include information about the extent to which fair value is used to measure assets and liabilities, the valuation methodologies used and its impact to earnings. Additionally, for financial instruments not recorded at fair value, the notes to the financial statements disclose the estimate of their fair value. Due to the judgments and uncertainties involved in the estimation process, the estimates could result in materially different results under different assumptions and conditions.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Calculation of Basic and Diluted Earnings Per Common Share	'
	The calculation of basic and diluted earnings per common share for the periods indicated is presented below.
			Three Months Ended				Nine Months Ended
			September 30,				September 30,
			2013		2012		2013		2012
	Net income		$	4,647	$	2,929	$	13,397	$	8,360
	Weighted average common shares applicable to basic EPS (1)			19,652,925		14,522,324		19,800,557		14,578,253
	Effect of dilutive potential common			319,877		186,049		278,308		249,175
	shares (2) (3)
	Weighted average common shares applicable to diluted EPS			19,972,802		14,708,373		20,078,865		14,827,428
	Earnings per share:
	Basic		$	0.24	$	0.2	$	0.68	$	0.57
	Diluted		$	0.23	$	0.2	$	0.67	$	0.56
	-1	Share-based compensation awards that qualify as participating securities (entiled to receive non-forfeitable dividends) are included in basic EPS.
	-2	Options to purchase 163,229 and 277,550 shares for the three months ended September 30, 2013 and 2012, respectively, and 197,628 and 197,300 shares for the nine months ended September 30, 2013 and 2012, respectively, were outstanding but not included in the computation of earnings per share because they were anti-dilutive.
	-3	Includes incremental shares related to dilutive stock options.

Accumulated_Other_Comprehensiv1

Accumulated Other Comprehensive Income (Tables)	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Components of Accumulated Other Comprehensive Income and Related Tax Effects	'
	The components of accumulated other comprehensive income and related tax effects are as follows:
		September 30,			December 31,
		2013			2012
	Net unrealized gain on securities available for sale	$	2,503		$	10,147
	Tax effect		(923	)		(3,847	)
	Net-of-tax amount		1,580			6,300
	Pension liability		(1,432	)		(1,432	)
	Tax effect		533			533
	Net-of-tax amount		(899	)		(899	)
	Accumulated other comprehensive income	$	681		$	5,401

Investment_Securities_Tables

Investment Securities (Tables)	9 Months Ended
	Sep. 30, 2013
Investments Debt And Equity Securities [Abstract]	'
Amortized Cost and Fair Value of Securities Classified as Available for Sale and Held to Maturity	'
	The amortized cost and fair value of securities classified as available for sale and held to maturity are as follows:
		Amortized		Unrealized
		Cost		Gains			Losses			Fair Value
	Securities Available for Sale
	September 30, 2013:
	Debt Securities:
	Government-sponsored enterprises	$	2,099	$	—		$	(188	)	$	1,911
	Government-sponsored and government-guaranteed mortgage-backed securities		232,372		5,589			(2,567	)		235,394
	Private label mortgage-backed securities		8		—			—			8
	Municipal bonds		26,149		284			(1,203	)		25,230
	Corporate bonds		1,292		588			—			1,880
	Total	$	261,920	$	6,461		$	(3,958	)	$	264,423
	December 31, 2012:
	Debt Securities:
	Government-sponsored enterprises	$	3,234	$	2		$	(3	)	$	3,233
	Government-sponsored and government-guaranteed mortgage-backed securities		248,370		9,836			(444	)		257,762
	Private label mortgage-backed securities		2,568		54			(56	)		2,566
	Municipal bonds		28,713		595			(481	)		28,827
	Corporate bonds		1,290		644			—			1,934
	Total	$	284,175	$	11,131		$	(984	)	$	294,322
		Amortized		Unrealized
		Cost		Gains			Losses			Fair Value
	Securities Held to Maturity
	September 30, 2013:
	Government-sponsored and government-guaranteed mortgage-backed securities	$	73,432	$	1,535		$	(332	)	$	74,635
	Private label mortgage-backed securities		58		2			—			60
	Industrial revenue bonds		18,410		—			—			18,410
	State of Israel bonds		175		—			—			175
	Municipal bonds		5,916		197			—			6,113
	Total	$	97,991	$	1,734		$	(332	)	$	99,393
	December 31, 2012:
	Government-sponsored and government-guaranteed mortgage-backed securities	$	57,986	$	2,214		$	—		$	60,200
	Private label mortgage-backed securities		79		2			—			81
	Industrial revenue bonds		18,847		—			—			18,847
	State of Israel bonds		150		—			—			150
	Municipal bonds		5,924		472			—			6,396
	Total	$	82,986	$	2,688		$	—		$	85,674
Scheduled Maturities of Debt Securities Available for Sale and Held to Maturity	'
	The scheduled maturities of debt securities available for sale and held to maturity at September 30, 2013 are shown below. Actual maturities will differ from contractual maturities because issuers generally have the right to call or prepay obligations with or without call or prepayment penalties.
		At September 30, 2013
		Securities					Securities
		Available for Sale					Held to Maturity
		Amortized					Amortized
		Cost		Fair Value			Cost			Fair Value
	Due in one year or less	$	—	$	—		$	125		$	125
	Due from one year to five years		2,278		2,338			810			845
	Due from five years to ten years		15,112		14,707			1,536			1,592
	Due after ten years		12,150		11,976			22,030			22,136
			29,540		29,021			24,501			24,698
	Mortgage-backed securities		232,380		235,402			73,490			74,695
		$	261,920	$	264,423		$	97,991		$	99,393
Gross Continuous Unrealized Losses and Fair Values	'
	Gross unrealized losses and fair values at September 30, 2013 and December 31, 2012 aggregated by investment category and the length of time that individual securities have been in a continuous unrealized loss position follow:
		Less than 12 months					12 months or longer						Total
		Fair		Unrealized			Fair			Unrealized			Number of		Fair		Unrealized
		Value		Losses			Value			Losses			Securities		Value		Losses
	At September 30, 2013:
	Securities Available for Sale
	Debt Securities:
	Government-sponsored enterprises	$	1,911	$	(188	)	$	—		$	—			5	$	1,911	$	(188	)
	Government-sponsored and government-guaranteed mortgage-backed securities		109,234		(2,331	)		11,354			(236	)		135		120,588		(2,567	)
	Municipal bonds		19,490		(1,203	)		—			—			47		19,490		(1,203	)
	Total	$	130,635	$	(3,722	)	$	11,354		$	(236	)		187	$	141,989	$	(3,958	)
	Securities Held to Maturity
	Government-sponsored and government-guaranteed mortgage-backed securities	$	16,017	$	(332	)	$	—		$	—			3	$	16,017	$	(332	)
	Total	$	16,017	$	(332	)	$	—		$	—			3	$	16,017	$	(332	)
		Less than 12 months					12 months or longer						Total
		Fair		Unrealized			Fair			Unrealized			Number of		Fair		Unrealized
		Value		Losses			Value			Losses			Securities		Value		Losses
	At December 31, 2012:
	Securities Available for Sale
	Debt Securities:
	Government-sponsored enterprises	$	1,998	$	(3	)	$	—		$	—			5	$	1,998	$	(3	)
	Government-sponsored and government-guaranteed mortgage- backed securities		41,537		(444	)		—			—			81		41,537		(444	)
	Private label mortgage-backed securities		1,671		(56	)		—			—			9		1,671		(56	)
	Municipal bonds		16,293		(481	)		—			—			38		16,293		(481	)
	Total	$	61,499	$	(984	)	$	—		$	—			133	$	61,499	$	(984	)

Loans_Tables

Loans (Tables)	9 Months Ended
	Sep. 30, 2013
Receivables [Abstract]	'
Summary of Components of Loan	'
	The components of the loan portfolio were as follows at September 30, 2013 and December 31, 2012:
		September 30,			December 31,
		2013			2012
	Commercial:
	Commercial and industrial	$	304,228		$	306,192
	Commercial real estate		872,340			814,692
	Construction		59,788			52,778
	Consumer:
	Residential real estate		459,714			441,874
	Home equity		179,507			179,039
	Consumer		17,920			21,501
	Total loans		1,893,497			1,816,076
	Net deferred loan costs and fees		2,653			3,414
	Allowance for loan losses		(13,642	)		(12,089	)
	Loans, net	$	1,882,508		$	1,807,401
Summary of Activity Pertaining to Allowance for Loan Losses	'
	A summary of the activity pertaining to the allowance for loan losses for the three and nine months ended September 30, 2013 and 2012 is as follows:
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Three Months Ended September 30, 2013:
	Beginning balance	$	3,374		$	5,831		$	1,034		$	627		$	595		$	676		$	387		$	80		$	466		$	13,070
	Charge-offs		(326	)		(106	)		—			—			—			(113	)		(53	)		(2	)		—			(600	)
	Recoveries		7			27			—			—			—			—			1			12			—			47
	Provision (credit)		(155	)		1,064			(10	)		7			(6	)		183			50			(22	)		14			1,125
	Ending balance	$	2,900		$	6,816		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,642
											Business Banking
		Commercial									Commercial			Banking
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Three Months Ended September 30, 2012:
	Beginning balance	$	2,828		$	5,232		$	742		$	727		$	683		$	690		$	379		$	97		$	373		$	11,751
	Charge-offs		(109	)		(97	)		—			(40	)		(12	)		(45	)		(40	)		(10	)		—			(353	)
	Recoveries		84			10			—			1			—			—			—			7			—			102
	Provision (credit)		163			242			67			85			70			55			69			(7	)		306			1,050
	Ending balance	$	2,966		$	5,387		$	809		$	773		$	741		$	700		$	408		$	87		$	679		$	12,550
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Nine Months Ended September 30, 2013:
	Beginning balance	$	2,680		$	5,497		$	710		$	788		$	706		$	602		$	383		$	83		$	640		$	12,089
	Charge-offs		(758	)		(158	)		—			(123	)		(122	)		(188	)		(79	)		(67	)		—			(1,495	)
	Recoveries		24			27			—			—			—			1			2			27			—			81
	Provision (credit)		954			1,450			314			(31	)		5			331			79			25			(160	)		2,967
	Ending balance	$	2,900		$	6,816		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,642
											Business Banking
		Commercial									Commercial			Banking
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	Nine Months Ended September 30, 2012:
	Beginning balance	$	3,446		$	5,572		$	860		$	—		$	—		$	666		$	474		$	114		$	—		$	11,132
	Charge-offs		(315	)		(370	)		(127	)		(128	)		(52	)		(133	)		(70	)		(15	)		—			(1,210	)
	Recoveries		123			45			1			2			—			—			—			7			—			178
	Provision (credit)		(288	)		140			75			899			793			167			4			(19	)		679			2,450
	Ending balance	$	2,966		$	5,387		$	809		$	773		$	741		$	700		$	408		$	87		$	679		$	12,550
Information Pertaining to Allowance for Loan Losses	'
	Further information pertaining to the allowance for loan losses at September 30, 2013 and December 31, 2012 is as follows:
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	At September 30, 2013:
	Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	$	30		$	400		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	430
	Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	$	2,870		$	6,416		$	1,024		$	634		$	589		$	746		$	385		$	68		$	480		$	13,212
	Total loans	$	272,989		$	792,503		$	59,788		$	31,239		$	79,837		$	459,714		$	179,507		$	17,920		$	—		$	1,893,497
	Loans deemed to be impaired and individually evaluated for impairment	$	5,112		$	2,364		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	7,476
	Loans not deemed to be impaired and collectively evaluated for impairment	$	267,617		$	788,198		$	59,788		$	31,239		$	79,837		$	459,714		$	179,507		$	17,920		$	—		$	1,883,820
	Loans acquired with deteriorated credit quality and deemed to be impaired	$	260		$	1,941		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	2,201
											Business Banking
		Commercial									Commercial
		and			Commercial						and			Commercial						Home
		Industrial			Real Estate			Construction			Industrial			Real Estate			Residential			Equity			Consumer			Unallocated			Total
	At December 31, 2012:
	Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	$	32		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	—		$	32
	Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	$	2,648		$	5,497		$	710		$	788		$	706		$	602		$	383		$	83		$	640		$	12,057
	Total loans	$	272,789		$	732,272		$	52,778		$	33,403		$	82,420		$	441,874		$	179,039		$	21,501		$	—		$	1,816,076
	Loans deemed to be impaired and individually evaluated for impairment	$	5,943		$	3,882		$	591		$	—		$	—		$	—		$	—		$	—		$	—		$	10,416
	Loans not deemed to be impaired and collectively evaluated for impairment	$	266,091		$	722,470		$	51,838		$	33,403		$	82,420		$	441,874		$	179,039		$	21,501		$	—		$	1,798,636
	Loans acquired with deteriorated credit quality and deemed to be impaired	$	755		$	5,920		$	349		$	—		$	—		$	—		$	—		$	—		$	—		$	7,024
Summary of Past Due Loans	'
	The following is a summary of past due loans at September 30, 2013 and December 31, 2012:
																				Recorded
								90 Days									Total			Investments
		30-59 Days			60-89 Days			and Over			Total						Financing			> 90 Days
		Past Due			Past Due			Past Due			Past Due			Current			Receivables			and Accruing
	At September 30, 2013:
	Commercial:
	Commercial and industrial	$	1,603		$	21		$	2,990		$	4,614		$	299,614		$	304,228		$	—
	Commercial real estate		3,633			4,873			3,462			11,968			860,372			872,340			—
	Construction		—			280			—			280			59,508			59,788			—
	Consumer:
	Residential real estate		—			1,786			4,224			6,010			453,704			459,714			—
	Home equity		392			190			941			1,523			177,984			179,507			—
	Consumer		323			—			117			440			17,480			17,920			—
	Total	$	5,951		$	7,150		$	11,734		$	24,835		$	1,868,662		$	1,893,497		$	—
	At December 31, 2012:
	Commercial:
	Commercial and industrial	$	3,974		$	1,155		$	4,442		$	9,571		$	296,621		$	306,192		$	—
	Commercial real estate		6,326			1,136			5,351			12,813			801,879			814,692			—
	Construction		2,853			—			—			2,853			49,925			52,778			—
	Consumer:
	Residential real estate		11,760			2,450			2,615			16,825			425,049			441,874			—
	Home equity		1,044			161			137			1,342			177,697			179,039			—
	Consumer		329			35			120			484			21,017			21,501			—
	Total	$	26,286		$	4,937		$	12,665		$	43,888		$	1,772,188		$	1,816,076		$	—
Summary of Impaired Loans	'
	The following is a summary of impaired loans at September 30, 2013 and December 31, 2012:
		At September 30, 2013									At December 31, 2012
					Unpaid									Unpaid
		Recorded			Principal			Related			Recorded			Principal			Related
		Investment			Balance			Allowance			Investment			Balance			Allowance
	With no related allowance recorded:
	Commercial and industrial	$	4,452		$	4,473					$	6,666		$	6,997
	Commercial real estate		3,682			4,182						9,802			10,736
	Construction		—			—						940			940
	Total	$	8,134		$	8,655					$	17,408		$	18,673
	With an allowance recorded:
	Commercial and industrial		920			920		$	30			32			32		$	32
	Commercial real estate		623			623			400			—			—			—
	Total	$	1,543		$	1,543		$	430		$	32		$	32		$	32
	Total impaired loans	$	9,677		$	10,198		$	430		$	17,440		$	18,705		$	32
Summary of Impaired and Non-Accrual Loans	'
	The following is a summary of information pertaining to impaired loans:
		Three Months Ended September 30, 2013									Three Months Ended September 30, 2012
		Average			Interest Income						Average			Interest Income
		Recorded						Recognized			Recorded						Recognized
		Investment on						on a			Investment on						on a
		Impaired Loans			Recognized			Cash Basis			Impaired Loans			Recognized			Cash Basis
	Commercial:
	Commercial and industrial	$	5,922		$	40		$	—		$	4,396		$	1		$	—
	Commercial real estate		5,907			19			—			3,378			10			—
	Construction		144			—			—			617			6			—
	Consumer:
	Residential real estate		—			23			23			—			—			—
	Consumer		—			—			—			—			1			1
	Total	$	11,973		$	82		$	23		$	8,391		$	18		$	1
		Nine Months Ended September 30, 2013									Nine Months Ended September 30, 2012
		Average			Interest Income						Average			Interest Income
		Recorded						Recognized			Recorded						Recognized
		Investment on						on a			Investment on						on a
		Impaired Loans			Recognized			Cash Basis			Impaired Loans			Recognized			Cash Basis
	Commercial:
	Commercial and industrial	$	6,268		$	454		$	329		$	4,320		$	10		$	8
	Commercial real estate		6,724			52			10			3,477			35			7
	Construction		850			5			—			708			19			—
	Consumer:
	Residential real estate		—			39			39			—			2			2
	Consumer		—			—			—			—			1			1
	Total	$	13,842		$	550		$	378		$	8,505		$	67		$	18
Summary of Non-Accrual Loans	'
	The following is a summary of non-accrual loans, at September 30, 2013 and December 31, 2012:
		September 30,			December 31,
		2013			2012
	Commercial:
	Commercial and industrial	$	3,510		$	5,538
	Commercial real estate		3,462			5,596
	Construction		—			349
	Consumer:
	Residential real estate		4,256			2,970
	Home equity		941			137
	Consumer		117			120
	Total	$	12,286		$	14,710
Modifications, Deemed to be Troubled Debt Restructurings	'
	The following table represents modifications that were deemed to be troubled debt restructurings for the nine months ended September 30, 2013 and 2012:
		Nine Months Ended September 30, 2013									Nine Months Ended September 30, 2012
		Number of			Outstanding Recorded Investment						Number of			Outstanding Recorded Investment
		Contracts			Pre-Modification			Post-Modification			Contracts			Pre-Modification			Post-Modification
	Troubled Debt
	Restructurings:
	Commercial and industrial		2		$	1,824		$	1,420			1		$	140		$	140
	Commercial real estate		—			—			—			4			1,211			1,211
	Construction		—			—			—			2			613			613
	Total		2		$	1,824		$	1,420			7		$	1,964		$	1,964
Company's Loan Segment by Internally Assigned Grades	'
	The following tables present the Company’s loan segment by internally assigned grades:
		At September 30, 2013
		Commercial			Commercial
		and Industrial			Real Estate			Construction			Total
	Commercial:
	Grade:
	Pass	$	276,722		$	817,581		$	55,842		$	1,150,145
	Special Mention		9,292			27,332			428			37,052
	Substandard		17,551			27,427			3,518			48,496
	Doubtful		663			—			—			663
	Total	$	304,228		$	872,340		$	59,788		$	1,236,356
		Residential			Home Equity			Consumer			Total
	Consumer:
	Grade:
	Pass	$	455,676		$	178,693		$	17,894		$	652,263
	Special Mention		—			—			—			—
	Substandard		4,038			814			26			4,878
	Doubtful		—			—			—			—
	Total	$	459,714		$	179,507		$	17,920		$	657,141
		At December 31, 2012
		Commercial			Commercial
		and Industrial			Real Estate			Construction			Total
	Commercial:
	Grade:
	Pass	$	275,279		$	762,240		$	46,196		$	1,083,715
	Special Mention		14,788			29,092			1,632			45,512
	Substandard		15,472			23,360			4,950			43,782
	Doubtful		653			—			—			653
	Total	$	306,192		$	814,692		$	52,778		$	1,173,662
		Residential			Home Equity			Consumer			Total
	Consumer:
	Grade:
	Pass	$	439,201		$	178,920		$	21,382		$	639,503
	Special Mention		—			—			—			—
	Substandard		2,673			119			119			2,911
	Doubtful		—			—			—			—
	Total	$	441,874		$	179,039		$	21,501		$	642,414

Commitments_Tables

Commitments (Tables)	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Financial Instruments with Off-Balance Sheet Risk	'
	Financial instruments with off-balance sheet risk at September 30, 2013 and December 31, 2012 were as follows:
		September 30,		December 31,
		2013		2012
	Unused lines of credit	$	338,049	$	308,683
	Amounts due mortgagors		100,533		36,365
	Standby letters of credit		5,499		3,573
	Commitments to originate loans		22,851		63,974

Deposits_Tables

Deposits (Tables)	9 Months Ended
	Sep. 30, 2013
Banking And Thrift [Abstract]	'
Deposit Accounts	'
	Deposit accounts, by type, are summarized as follows at September 30, 2013 and December 31, 2012:
		September 30,		December 31,
		2013		2012
	Demand	$	333,206	$	307,302
	NOW		86,545		87,983
	Savings		335,623		350,188
	Money market		455,547		395,293
	Certificates of deposit		735,477		707,409
		$	1,946,398	$	1,848,175

Fair_Values_of_Assets_and_Liab1

Fair Values of Assets and Liabilities (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Assets Measured at Fair Value on Recurring Basis	'
	Assets measured at fair value on a recurring basis, are summarized below:
									Total
		Level 1			Level 2		Level 3		Fair Value
	At September 30, 2013
	Securities available for sale:
	Government-sponsored enterprises	$	—		$	1,911	$	—	$	1,911
	Government-sponsored and government-guaranteed mortgage-backed securities		—			235,394		—		235,394
	Private label mortgage-backed securities		—			8		—		8
	Municipal bonds		—			25,230		—		25,230
	Corporate bonds		—			—		1,880		1,880
	Total	$	—		$	262,543	$	1,880	$	264,423
									Total
		Level 1			Level 2		Level 3		Fair Value
	At December 31, 2012
	Securities available for sale:
	Government-sponsored enterprises	$	—		$	3,233	$	—	$	3,233
	Government-sponsored and government-guaranteed mortgage-backed securities		—			257,762		—		257,762
	Private label mortgage-backed securities		—			2,566		—		2,566
	Municipal bonds		—			28,827		—		28,827
	Corporate bonds		—			—		1,934		1,934
	Total	$	—		$	292,388	$	1,934	$	294,322
Changes in Level 3 Recurring Fair Value of Financial Instruments	'
	The table below presents the changes in Level 3 assets measured at fair value on a recurring basis for the nine months ended September 30, 2013.
	Balance at December 31, 2012	$	1,934
	Change in unrealized gain		(54	)
	Balance at September 30, 2013	$	1,880
Fair Value Hierarchy Used to Determine the Adjustment and Carrying Value of Related Individual Assets	'
	The following tables summarize the fair value hierarchy used to determine the adjustment and the carrying value of the related individual assets for the three and nine months ended September 30, 2013 and 2012.
									Three Months Ended			Nine Months Ended
									September 30, 2013			September 30, 2013
		At September 30, 2013							Total			Total
		Level 1			Level 2		Level 3		Gains/(Losses)			Gains/(Losses)
	Assets:
	Loans	$	—		$	—	$	714	$	57		$	(565	)
	Other real estate owned		—			—		711		—			(135	)
	Total assets	$	—		$	—	$	1,425	$	57		$	(700	)
									Three Months Ended			Nine Months Ended
									September 30, 2012			September 30, 2012
		At September 30, 2012							Total			Total
		Level 1			Level 2		Level 3		Gains/(Losses)			Gains/(Losses)
	Assets:
	Loans	$	—		$	—	$	722	$	(116	)	$	(126	)
	Other real estate owned		—			—		1,070		(134	)		(184	)
	Other assets		—			—		595		(37	)		(37	)
	Total assets	$	—		$	—	$	2,387	$	(287	)	$	(347	)
Fair Values of Financial Instruments	'
	The fair value of the Company’s financial instruments is as follows at dates indicated:
		At September 30, 2013
		Carrying										Estimated
		Value			Level 1		Level 2		Level 3			Fair Value
	Financial Assets:
	Cash and cash equivalents	$	58,960		$	58,960	$	—	$	—		$	58,960
	Securities available for sale		264,423			—		262,543		1,880			264,423
	Securities held to maturity		97,991			—		99,393		—			99,393
	Stock in Federal Home Loan Bank of Boston		17,334			—		—		17,334			17,334
	Net loans and loans held for sale		1,882,508			—		—		1,887,816			1,887,816
	Financial Liabilities:
	Deposits (with no stated maturity)		1,210,921			—		—		1,210,921			1,210,921
	Time deposits		735,477			—		—		740,330			740,330
	Federal Home Loan Bank of Boston advances		151,029			—		—		153,706			153,706
	Repurchase agreements		60,446			—		—		60,967			60,967
	Subordinated debentures		5,933			—		5,933		—			5,933
		At December 31, 2012
		Carrying										Estimated
		Value			Level 1		Level 2		Level 3			Fair Value
	Financial Assets:
	Cash and cash equivalents	$	30,679		$	30,679	$	—	$	—		$	30,679
	Securities available for sale		294,322			—		292,388		1,934			294,322
	Securities held to maturity		82,986			—		85,674		—			85,674
	Stock in Federal Home Loan Bank of Boston		18,554			—		—		18,554			18,554
	Net loans and loans held for sale		1,808,033			—		—		1,846,519			1,846,519
	Financial Liabilities:
	Deposits (with no stated maturity)		1,140,766			—		—		1,140,766			1,140,766
	Time deposits		707,409			—		—		711,845			711,845
	Federal Home Loan Bank of Boston advances		141,525			—		—		145,543			145,543
	Repurchase agreements		69,229			—		—		70,082			70,082
	Subordinated debentures		9,630			—		9,630		—			9,630

Pension_and_Postretirement_Ben1

Pension and Postretirement Benefit Plans (Tables)	9 Months Ended
	Sep. 30, 2013
Compensation And Retirement Disclosure [Abstract]	'
Components of Net Periodic Benefit Cost	'
	The following table presents the components of the net periodic benefit cost for the indicated periods:
		For the Three Months Ended September 30,								For the Nine Months Ended September 30,
		2013				2012				2013				2012
				Director				Director				Director				Director
				Retirement				Retirement				Retirement				Retirement
		SERP		Plan		SERP		Plan		SERP		Plan		SERP		Plan
	Periodic benefit cost:
	Service cost	$	101	$	14	$	78	$	24	$	301	$	41	$	236	$	70
	Interest cost		47		11		44		14		141		33		132		42
	Total pension cost		148		25		122		38		442		74		368		112
	Prior service cost amortization		50		10		29		9		150		32		86		27
	Net loss amortization		—		12		—		2		—		36		—		8
	Net periodic benefit cost	$	198	$	47	$	151	$	49	$	592	$	142	$	454	$	147

Critical_Accounting_Policies_A

Critical Accounting Policies - Additional Information (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Accounting Policies [Abstract]	'	'
Maximum amount of commercial and industrial loans	$250	'
Maximum amount of commercial real estate loans	500	'
Reserve for unfunded commitments	$213	$89

Earnings_Per_Share_Calculation

Earnings Per Share - Calculation of Basic and Diluted Earnings Per Common Share (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]	'	'	'	'
Net income	$4,647	$2,929	$13,397	$8,360
Weighted average common shares applicable to basic EPS	19,652,925	14,522,324	19,800,557	14,578,253
Effect of dilutive potential common shares	319,877	186,049	278,308	249,175
Weighted average common shares applicable to diluted EPS	19,972,802	14,708,373	20,078,865	14,827,428
Earnings per share:	'	'	'	'
Basic	$0.24	$0.20	$0.68	$0.57
Diluted	$0.23	$0.20	$0.67	$0.56

Earnings_Per_Share_Calculation1

Earnings Per Share - Calculation of Basic and Diluted Earnings Per Common Share (Parenthetical) (Detail) (Stock Options [Member])	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Stock Options [Member]	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Options to purchase, shares	163,229	277,550	197,628	197,300

Accumulated_Other_Comprehensiv2

Accumulated Other Comprehensive Income - Components of Accumulated Other Comprehensive Income and Related Tax Effects (Detail) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012
						Net Unrealized Gain on Securities Available for Sale [Member]	Net Unrealized Gain on Securities Available for Sale [Member]	Pension Liability [Member]	Pension Liability [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'	'	'	'	'	'	'	'
Before tax amount	'	'	'	'	'	$2,503	$10,147	($1,432)	($1,432)
Tax effect	-1,714	-890	-5,008	-2,853	'	-923	-3,847	533	533
Net-of-tax amount	'	'	'	'	'	1,580	6,300	-899	-899
Accumulated other comprehensive income	$681	'	$681	'	$5,401	'	'	'	'

Investment_Securities_Amortize

Investment Securities - Amortized Cost and Fair Value of Securities Classified as Available for Sale and Held to Maturity (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	$261,920	$284,175
Securities Available for Sale, Unrealized Gains	6,461	11,131
Securities Available for Sale, Unrealized Losses	-3,958	-984
Securities Available for Sale, Fair Value	264,423	294,322
Securities Held to Maturity, Amortized Cost	97,991	82,986
Securities Held to Maturity, Unrealized Gains	1,734	2,688
Securities Held to Maturity, Unrealized Losses	-332	'
Securities Held to Maturity, Fair Value	99,393	85,674
Government-Sponsored Enterprises [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	2,099	3,234
Securities Available for Sale, Unrealized Gains	'	2
Securities Available for Sale, Unrealized Losses	-188	-3
Securities Available for Sale, Fair Value	1,911	3,233
Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	232,372	248,370
Securities Available for Sale, Unrealized Gains	5,589	9,836
Securities Available for Sale, Unrealized Losses	-2,567	-444
Securities Available for Sale, Fair Value	235,394	257,762
Securities Held to Maturity, Amortized Cost	73,432	57,986
Securities Held to Maturity, Unrealized Gains	1,535	2,214
Securities Held to Maturity, Unrealized Losses	-332	'
Securities Held to Maturity, Fair Value	74,635	60,200
Private Label Mortgage-Backed Securities [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	8	2,568
Securities Available for Sale, Unrealized Gains	'	54
Securities Available for Sale, Unrealized Losses	'	-56
Securities Available for Sale, Fair Value	8	2,566
Securities Held to Maturity, Amortized Cost	58	79
Securities Held to Maturity, Unrealized Gains	2	2
Securities Held to Maturity, Unrealized Losses	'	'
Securities Held to Maturity, Fair Value	60	81
Municipal Bonds [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	26,149	28,713
Securities Available for Sale, Unrealized Gains	284	595
Securities Available for Sale, Unrealized Losses	-1,203	-481
Securities Available for Sale, Fair Value	25,230	28,827
Securities Held to Maturity, Amortized Cost	5,916	5,924
Securities Held to Maturity, Unrealized Gains	197	472
Securities Held to Maturity, Unrealized Losses	'	'
Securities Held to Maturity, Fair Value	6,113	6,396
Corporate Bonds [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Amortized Cost	1,292	1,290
Securities Available for Sale, Unrealized Gains	588	644
Securities Available for Sale, Unrealized Losses	'	'
Securities Available for Sale, Fair Value	1,880	1,934
Industrial Revenue Bonds [Member]	'	'
Investment [Line Items]	'	'
Securities Held to Maturity, Amortized Cost	18,410	18,847
Securities Held to Maturity, Unrealized Gains	'	'
Securities Held to Maturity, Unrealized Losses	'	'
Securities Held to Maturity, Fair Value	18,410	18,847
State of Israel Bonds [Member]	'	'
Investment [Line Items]	'	'
Securities Held to Maturity, Amortized Cost	175	150
Securities Held to Maturity, Unrealized Gains	'	'
Securities Held to Maturity, Unrealized Losses	'	'
Securities Held to Maturity, Fair Value	$175	$150

Investment_Securities_Schedule

Investment Securities - Scheduled Maturities of Debt Securities Available for Sale and Held to Maturity (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Investments Debt And Equity Securities [Abstract]	'	'
Securities Available for Sale, Amortized Cost, Due in one year or less	'	'
Securities Available for Sale, Amortized Cost, Due from one year to five years	2,278	'
Securities Available for Sale, Amortized Cost, Due from five years to ten years	15,112	'
Securities Available for Sale, Amortized Cost, Due after ten years	12,150	'
Securities Available for Sale, Amortized Cost, Total due maturity	29,540	'
Securities Available for Sale, Amortized Cost, Mortgage-backed securities	232,380	'
Securities Available for Sale, Amortized Cost	261,920	284,175
Securities Available for Sale, Fair Value, Due in one year or less	'	'
Securities Available for Sale, Fair Value, Due from one year to five years	2,338	'
Securities Available for Sale, Fair Value, Due from five years to ten years	14,707	'
Securities Available for Sale, Fair Value, Due after ten years	11,976	'
Securities Available for Sale, Fair Value, Total due maturity	29,021	'
Securities Available for Sale, Fair Value, Mortgage-backed securities	235,402	'
Securities Available for Sale, Fair Value	264,423	294,322
Securities Held to Maturity, Amortized Cost, Due in one year or less	125	'
Securities Held to Maturity, Amortized Cost, Due from one year to five years	810	'
Securities Held to Maturity, Amortized Cost, Due from five years to ten years	1,536	'
Securities Held to Maturity, Amortized Cost, Due after ten years	22,030	'
Securities Held to Maturity, Amortized Cost, Total due maturity	24,501	'
Securities Held to Maturity, Amortized Cost, Mortgage-backed securities	73,490	'
Securities Held to Maturity, Amortized Cost	97,991	82,986
Securities Held to Maturity, Fair Value, Due in one year or less	125	'
Securities Held to Maturity, Fair Value, Due from one year to five years	845	'
Securities Held to Maturity, Fair Value, Due from five years to ten years	1,592	'
Securities Held to Maturity, Fair Value, Due after ten years	22,136	'
Securities Held to Maturity, Fair Value, Total due maturity	24,698	'
Securities Held-to-maturity, Fair Value, Mortgage-backed securities	74,695	'
Securities Held to Maturity, Fair Value	$99,393	$85,674

Investment_Securities_Gross_Co

Investment Securities - Gross Continuous Unrealized Losses and Fair Values (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Securities	Securities
Investment [Line Items]	'	'
Securities Available for Sale, Less than 12 months, Fair Value	$130,635	$61,499
Securities Available for Sale, 12 months or longer, Fair Value	11,354	'
Securities Available for Sale, Fair Value, Total	141,989	61,499
Securities Held to Maturity, Less than 12 months, Fair Value	16,017	'
Securities Held to Maturity, 12 months or longer, Fair Value	'	'
Securities Held to Maturity, Fair Value, Total	16,017	'
Securities Available for Sale, Less than 12 months, Unrealized Losses	-3,722	-984
Securities Available for Sale, 12 months or longer, Unrealized Losses	-236	'
Securities Available for Sale, Number of Securities	187	133
Securities Available for Sale, Unrealized Losses, Total	-3,958	-984
Securities Held to Maturity, Less than 12 months, Unrealized Losses	-332	'
Securities Held to Maturity, 12 months or longer, Unrealized Losses	'	'
Securities Held to Maturity, Number of Securities	3	'
Securities Held to Maturity, Unrealized Losses, Total	-332	'
Government-Sponsored Enterprises [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Less than 12 months, Fair Value	1,911	1,998
Securities Available for Sale, 12 months or longer, Fair Value	'	'
Securities Available for Sale, Fair Value, Total	1,911	1,998
Securities Available for Sale, Less than 12 months, Unrealized Losses	-188	-3
Securities Available for Sale, 12 months or longer, Unrealized Losses	'	'
Securities Available for Sale, Number of Securities	5	5
Securities Available for Sale, Unrealized Losses, Total	-188	-3
Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Less than 12 months, Fair Value	109,234	41,537
Securities Available for Sale, 12 months or longer, Fair Value	11,354	'
Securities Available for Sale, Fair Value, Total	120,588	41,537
Securities Held to Maturity, Less than 12 months, Fair Value	16,017	'
Securities Held to Maturity, 12 months or longer, Fair Value	'	'
Securities Held to Maturity, Fair Value, Total	16,017	'
Securities Available for Sale, Less than 12 months, Unrealized Losses	-2,331	-444
Securities Available for Sale, 12 months or longer, Unrealized Losses	-236	'
Securities Available for Sale, Number of Securities	135	81
Securities Available for Sale, Unrealized Losses, Total	-2,567	-444
Securities Held to Maturity, Less than 12 months, Unrealized Losses	-332	'
Securities Held to Maturity, 12 months or longer, Unrealized Losses	'	'
Securities Held to Maturity, Number of Securities	3	'
Securities Held to Maturity, Unrealized Losses, Total	-332	'
Private Label Mortgage-Backed Securities [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Less than 12 months, Fair Value	'	1,671
Securities Available for Sale, 12 months or longer, Fair Value	'	'
Securities Available for Sale, Fair Value, Total	'	1,671
Securities Available for Sale, Less than 12 months, Unrealized Losses	'	-56
Securities Available for Sale, 12 months or longer, Unrealized Losses	'	'
Securities Available for Sale, Number of Securities	'	9
Securities Available for Sale, Unrealized Losses, Total	'	-56
Securities Held to Maturity, Unrealized Losses, Total	'	'
Municipal Bonds [Member]	'	'
Investment [Line Items]	'	'
Securities Available for Sale, Less than 12 months, Fair Value	19,490	16,293
Securities Available for Sale, 12 months or longer, Fair Value	'	'
Securities Available for Sale, Fair Value, Total	19,490	16,293
Securities Available for Sale, Less than 12 months, Unrealized Losses	-1,203	-481
Securities Available for Sale, 12 months or longer, Unrealized Losses	'	'
Securities Available for Sale, Number of Securities	47	38
Securities Available for Sale, Unrealized Losses, Total	-1,203	-481
Securities Held to Maturity, Unrealized Losses, Total	'	'

Investment_Securities_Addition

Investment Securities - Additional Information (Detail)	Sep. 30, 2013
	Investmentsecurities
Available For Sale Securities [Abstract]	'
Fair value of company's securities declined	0

Loans_Summary_of_Components_of

Loans - Summary of Components of Loan (Detail) (USD $)	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Commercial loan	$1,236,356	'	$1,173,662	'	'	'
Consumer Loan	657,141	'	642,414	'	'	'
Total loans	1,893,497	'	1,816,076	'	'	'
Net deferred loan costs and fees	2,653	'	3,414	'	'	'
Allowance for loan losses	-13,642	-13,070	-12,089	-12,550	-11,751	-11,132
Loans, net	1,882,508	'	1,807,401	'	'	'
Residential Real Estate [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Consumer Loan	459,714	'	441,874	'	'	'
Total loans	459,714	'	441,874	'	'	'
Home Equity [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Consumer Loan	179,507	'	179,039	'	'	'
Total loans	179,507	'	179,039	'	'	'
Allowance for loan losses	-385	-387	-383	-408	-379	-474
Consumer [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Consumer Loan	17,920	'	21,501	'	'	'
Commercial and Industrial [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Commercial loan	304,228	'	306,192	'	'	'
Total loans	272,989	'	272,789	'	'	'
Allowance for loan losses	-2,900	-3,374	-2,680	-2,966	-2,828	-3,446
Commercial Real Estate [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Commercial loan	872,340	'	814,692	'	'	'
Total loans	792,503	'	732,272	'	'	'
Allowance for loan losses	-6,816	-5,831	-5,497	-5,387	-5,232	-5,572
Construction [Member]	'	'	'	'	'	'
Accounts, Notes, Loans and Financing Receivable [Line Items]	'	'	'	'	'	'
Commercial loan	59,788	'	52,778	'	'	'
Total loans	59,788	'	52,778	'	'	'
Allowance for loan losses	($1,024)	($1,034)	($710)	($809)	($742)	($860)

Loans_Additional_Information_D

Loans - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]	'	'
Servicing loans for participants	$72	$57.70
Transferred portion of loan as secured debt	$2.60	$2.40

Loans_Summary_of_Activity_Pert

Loans - Summary of Activity Pertaining to Allowance for Loan Losses (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	$13,070	$11,751	$12,089	$11,132
Charge-offs	-600	-353	-1,495	-1,210
Recoveries	47	102	81	178
Provision (credit)	1,125	1,050	2,967	2,450
Ending balance	13,642	12,550	13,642	12,550
Commercial and Industrial [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	3,374	2,828	2,680	3,446
Charge-offs	-326	-109	-758	-315
Recoveries	7	84	24	123
Provision (credit)	-155	163	954	-288
Ending balance	2,900	2,966	2,900	2,966
Commercial Real Estate [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	5,831	5,232	5,497	5,572
Charge-offs	-106	-97	-158	-370
Recoveries	27	10	27	45
Provision (credit)	1,064	242	1,450	140
Ending balance	6,816	5,387	6,816	5,387
Construction [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	1,034	742	710	860
Charge-offs	'	'	'	-127
Recoveries	'	'	'	1
Provision (credit)	-10	67	314	75
Ending balance	1,024	809	1,024	809
Business Banking Commercial and Industrial [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	627	727	788	'
Charge-offs	'	-40	-123	-128
Recoveries	'	1	'	2
Provision (credit)	7	85	-31	899
Ending balance	634	773	634	773
Business Banking Commercial Real Estate [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	595	683	706	'
Charge-offs	'	-12	-122	-52
Recoveries	'	'	'	'
Provision (credit)	-6	70	5	793
Ending balance	589	741	589	741
Residential Mortgage [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	676	690	602	666
Charge-offs	-113	-45	-188	-133
Recoveries	'	'	1	'
Provision (credit)	183	55	331	167
Ending balance	746	700	746	700
Home Equity [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	387	379	383	474
Charge-offs	-53	-40	-79	-70
Recoveries	1	'	2	'
Provision (credit)	50	69	79	4
Ending balance	385	408	385	408
Consumer [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	80	97	83	114
Charge-offs	-2	-10	-67	-15
Recoveries	12	7	27	7
Provision (credit)	-22	-7	25	-19
Ending balance	68	87	68	87
Unallocated [Member]	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'
Beginning balance	466	373	640	'
Charge-offs	'	'	'	'
Recoveries	'	'	'	'
Provision (credit)	14	306	-160	679
Ending balance	$480	$679	$480	$679

Loans_Information_Pertaining_t

Loans - Information Pertaining to Allowance for Loan Losses (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	$430	$32
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	13,212	12,057
Total loans	1,893,497	1,816,076
Loans deemed to be impaired and individually evaluated for impairment	7,476	10,416
Loans not deemed to be impaired and collectively evaluated for impairment	1,883,820	1,798,636
Loans acquired with deteriorated credit quality and deemed to be impaired	2,201	7,024
Commercial and Industrial [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	30	32
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	2,870	2,648
Total loans	272,989	272,789
Loans deemed to be impaired and individually evaluated for impairment	5,112	5,943
Loans not deemed to be impaired and collectively evaluated for impairment	267,617	266,091
Loans acquired with deteriorated credit quality and deemed to be impaired	260	755
Commercial Real Estate [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	400	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	6,416	5,497
Total loans	792,503	732,272
Loans deemed to be impaired and individually evaluated for impairment	2,364	3,882
Loans not deemed to be impaired and collectively evaluated for impairment	788,198	722,470
Loans acquired with deteriorated credit quality and deemed to be impaired	1,941	5,920
Construction [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	1,024	710
Total loans	59,788	52,778
Loans deemed to be impaired and individually evaluated for impairment	'	591
Loans not deemed to be impaired and collectively evaluated for impairment	59,788	51,838
Loans acquired with deteriorated credit quality and deemed to be impaired	'	349
Business Banking Commercial and Industrial [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	634	788
Total loans	31,239	33,403
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	31,239	33,403
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'
Business Banking Commercial Real Estate [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	589	706
Total loans	79,837	82,420
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	79,837	82,420
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'
Residential Mortgage [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	746	602
Total loans	459,714	441,874
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	459,714	441,874
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'
Home Equity [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	385	383
Total loans	179,507	179,039
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	179,507	179,039
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'
Consumer [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	68	83
Total loans	17,920	21,501
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	17,920	21,501
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'
Unallocated [Member]	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'
Amount of allowance for loan losses for loans deemed to be impaired and individually evaluated for impairment	'	'
Amount of allowance for loan losses for loans not deemed to be impaired and collectively evaluated for impairment	480	640
Total loans	'	'
Loans deemed to be impaired and individually evaluated for impairment	'	'
Loans not deemed to be impaired and collectively evaluated for impairment	'	'
Loans acquired with deteriorated credit quality and deemed to be impaired	'	'

Loans_Summary_of_Past_Due_Loan

Loans - Summary of Past Due Loans (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	$5,951	$26,286
60-89 Days Past Due	7,150	4,937
90 Days and Over Past Due	11,734	12,665
Total Past Due	24,835	43,888
Current	1,868,662	1,772,188
Total Financing Receivables	1,893,497	1,816,076
Recorded Investments > 90 Days and Accruing	'	'
Commercial and Industrial [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	1,603	3,974
60-89 Days Past Due	21	1,155
90 Days and Over Past Due	2,990	4,442
Total Past Due	4,614	9,571
Current	299,614	296,621
Total Financing Receivables	272,989	272,789
Recorded Investments > 90 Days and Accruing	'	'
Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	3,633	6,326
60-89 Days Past Due	4,873	1,136
90 Days and Over Past Due	3,462	5,351
Total Past Due	11,968	12,813
Current	860,372	801,879
Total Financing Receivables	792,503	732,272
Recorded Investments > 90 Days and Accruing	'	'
Construction [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	'	2,853
60-89 Days Past Due	280	'
90 Days and Over Past Due	'	'
Total Past Due	280	2,853
Current	59,508	49,925
Total Financing Receivables	59,788	52,778
Recorded Investments > 90 Days and Accruing	'	'
Residential Real Estate [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	'	11,760
60-89 Days Past Due	1,786	2,450
90 Days and Over Past Due	4,224	2,615
Total Past Due	6,010	16,825
Current	453,704	425,049
Total Financing Receivables	459,714	441,874
Recorded Investments > 90 Days and Accruing	'	'
Home Equity [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	392	1,044
60-89 Days Past Due	190	161
90 Days and Over Past Due	941	137
Total Past Due	1,523	1,342
Current	177,984	177,697
Total Financing Receivables	179,507	179,039
Recorded Investments > 90 Days and Accruing	'	'
Consumer [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
30-59 Days Past Due	323	329
60-89 Days Past Due	'	35
90 Days and Over Past Due	117	120
Total Past Due	440	484
Current	17,480	21,017
Total Financing Receivables	17,920	21,501
Recorded Investments > 90 Days and Accruing	'	'

Loans_Summary_of_Impaired_Loan

Loans - Summary of Impaired Loans (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Impaired [Line Items]	'	'
Recorded Investment	$8,134	$17,408
Recorded Investment	9,677	17,440
Unpaid Principal Balance	8,655	18,673
Total Unpaid Principal Balance	10,198	18,705
Recorded Investment	1,543	32
Unpaid Principal Balance	1,543	32
Related Allowance	430	32
Commercial and Industrial [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Recorded Investment	4,452	6,666
Unpaid Principal Balance	4,473	6,997
Recorded Investment	920	32
Unpaid Principal Balance	920	32
Related Allowance	30	32
Commercial Real Estate [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Recorded Investment	3,682	9,802
Unpaid Principal Balance	4,182	10,736
Recorded Investment	623	'
Unpaid Principal Balance	623	'
Related Allowance	400	'
Construction [Member]	'	'
Financing Receivable, Impaired [Line Items]	'	'
Recorded Investment	'	940
Unpaid Principal Balance	'	$940

Loans_Summary_of_Impaired_and_

Loans - Summary of Impaired and Non-Accrual Loans (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	$11,973	$8,391	$13,842	$8,505
Recognized, Interest Income	82	18	550	67
Interest Income, Recognized on a Cash Basis	23	1	378	18
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	5,922	4,396	6,268	4,320
Recognized, Interest Income	40	1	454	10
Interest Income, Recognized on a Cash Basis	'	'	329	8
Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	5,907	3,378	6,724	3,477
Recognized, Interest Income	19	10	52	35
Interest Income, Recognized on a Cash Basis	'	'	10	7
Commercial Portfolio Segment [Member] | Construction [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	144	617	850	708
Recognized, Interest Income	'	6	5	19
Interest Income, Recognized on a Cash Basis	'	'	'	'
Consumer Portfolio Segment [Member] | Residential Real Estate [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	'	'	'	'
Recognized, Interest Income	23	'	39	2
Interest Income, Recognized on a Cash Basis	23	'	39	2
Consumer Portfolio Segment [Member] | Consumer [Member]	'	'	'	'
Financing Receivable, Impaired [Line Items]	'	'	'	'
Average Recorded Investment on Impaired Loans	'	'	'	'
Recognized, Interest Income	'	1	'	1
Interest Income, Recognized on a Cash Basis	'	$1	'	$1

Loans_Summary_of_NonAccrual_Lo

Loans - Summary of Non-Accrual Loans (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	$12,286	$14,710
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	3,510	5,538
Commercial Portfolio Segment [Member] | Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	3,462	5,596
Commercial Portfolio Segment [Member] | Construction [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	'	349
Consumer Portfolio Segment [Member] | Residential Real Estate [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	4,256	2,970
Consumer Portfolio Segment [Member] | Home Equity [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	941	137
Consumer Portfolio Segment [Member] | Consumer [Member]	'	'
Financing Receivable, Recorded Investment, Past Due [Line Items]	'	'
Summary of non-accrual loans	$117	$120

Loans_Modifications_Deemed_to_

Loans - Modifications, Deemed to be Troubled Debt Restructurings (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
	Contract	Contract
Financing Receivable, Modifications [Line Items]	'	'
Number of Contracts	2	7
Pre-Modification Recorded Investment	$1,824	$1,964
Post-Modification Recorded Investment	1,420	1,964
Commercial and Industrial [Member]	'	'
Financing Receivable, Modifications [Line Items]	'	'
Number of Contracts	2	1
Pre-Modification Recorded Investment	1,824	140
Post-Modification Recorded Investment	1,420	140
Commercial Real Estate [Member]	'	'
Financing Receivable, Modifications [Line Items]	'	'
Number of Contracts	'	4
Pre-Modification Recorded Investment	'	1,211
Post-Modification Recorded Investment	'	1,211
Construction [Member]	'	'
Financing Receivable, Modifications [Line Items]	'	'
Number of Contracts	'	2
Pre-Modification Recorded Investment	'	613
Post-Modification Recorded Investment	'	$613

Loans_Companys_Loan_Segment_by

Loans - Company's Loan Segment by Internally Assigned Grades (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	$1,236,356	$1,173,662
Consumer Loan	657,141	642,414
Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	1,150,145	1,083,715
Consumer Loan	652,263	639,503
Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	37,052	45,512
Consumer Loan	'	'
Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	48,496	43,782
Consumer Loan	4,878	2,911
Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	663	653
Consumer Loan	'	'
Residential [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	459,714	441,874
Residential [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	455,676	439,201
Residential [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Residential [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	4,038	2,673
Residential [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Home Equity [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	179,507	179,039
Home Equity [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	178,693	178,920
Home Equity [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Home Equity [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	814	119
Home Equity [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Consumer [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	17,920	21,501
Consumer [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	17,894	21,382
Consumer [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Consumer [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	26	119
Consumer [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Consumer Loan	'	'
Commercial and Industrial [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	304,228	306,192
Commercial and Industrial [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	276,722	275,279
Commercial and Industrial [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	9,292	14,788
Commercial and Industrial [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	17,551	15,472
Commercial and Industrial [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	663	653
Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	872,340	814,692
Commercial Real Estate [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	817,581	762,240
Commercial Real Estate [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	27,332	29,092
Commercial Real Estate [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	27,427	23,360
Commercial Real Estate [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	'	'
Construction [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	59,788	52,778
Construction [Member] | Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	55,842	46,196
Construction [Member] | Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	428	1,632
Construction [Member] | Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	3,518	4,950
Construction [Member] | Doubtful [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Commercial loan	'	'

Commitments_Financial_Instrume

Commitments - Financial Instruments with Off-Balance Sheet Risk (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Commitments And Contingencies Disclosure [Abstract]	'	'
Unused lines of credit	$338,049	$308,683
Amounts due mortgagors	100,533	36,365
Standby letters of credit	5,499	3,573
Commitments to originate loans	$22,851	$63,974

Commitments_Additional_Informa

Commitments - Additional Information (Detail) (USD $)	9 Months Ended				12 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013	Aug. 31, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013
		Low Income Housing Tax Credit [Member]	New Market Tax Credit Fund [Member]	New Market Tax Credit Fund [Member]	New Markets Housing Tax Credit Fund [Member]	Class A [Member]	Class B [Member]
Commitment And Contingencies [Line Items]	'	'	'	'	'	'	'
Commitment to invest in housing tax credits fund	$10,000,000	'	'	'	'	'	'
Representing percentage of Class A	'	'	'	'	'	25.00%	'
Investment in funds	8,400,000	'	'	'	'	'	'
Net operating losses related to investment in low income housing tax credit funds	2,000,000	165,000	'	'	'	'	'
Amount invested in low income housing tax credit funds, net carrying value	6,400,000	972,000	979,000	'	1,800,000	'	'
Transfer of investment period	'	'	'	'	'	'	'10 years
Percentage of tax credits and tax benefits	'	'	'	'	'	95.00%	'
Net operating losses period	'8 years	'	'	'	'	'	'
Investment in housing tax credit fund	'	1,100,000	'	979,000	1,800,000	'	'
Percentage of interest	'	'	'	'	50.00%	'	'
Loss on investment in housing tax credit fund	'	'	'	'	33,000	'	'
Commitment to invest in housing tax credit fund	'	$2,000,000	'	'	'	'	'

Deposits_Deposits_Accounts_Det

Deposits - Deposits Accounts (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Banking And Thrift [Abstract]	'	'
Demand	$333,206	$307,302
NOW	86,545	87,983
Savings	335,623	350,188
Money market	455,547	395,293
Certificates of deposit	735,477	707,409
Total deposits	$1,946,398	$1,848,175

Fair_Values_of_Assets_and_Liab2

Fair Values of Assets and Liabilities - Assets Measured at Fair Value on Recurring Basis (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	$264,423	$294,322
Government-Sponsored Enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,911	3,233
Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	235,394	257,762
Private Label Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	8	2,566
Municipal Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	25,230	28,827
Corporate Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,880	1,934
Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	262,543	292,388
Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,880	1,934
Assets Measured at Fair Value on a Recurring Basis [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	264,423	294,322
Assets Measured at Fair Value on a Recurring Basis [Member] | Government-Sponsored Enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,911	3,233
Assets Measured at Fair Value on a Recurring Basis [Member] | Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	235,394	257,762
Assets Measured at Fair Value on a Recurring Basis [Member] | Private Label Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	8	2,566
Assets Measured at Fair Value on a Recurring Basis [Member] | Municipal Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	25,230	28,827
Assets Measured at Fair Value on a Recurring Basis [Member] | Corporate Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,880	1,934
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Government-Sponsored Enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Private Label Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Municipal Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Corporate Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	262,543	292,388
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Government-Sponsored Enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,911	3,233
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	235,394	257,762
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Private Label Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	8	2,566
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Municipal Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	25,230	28,827
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Corporate Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	1,880	1,934
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Government-Sponsored Enterprises [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Government-Sponsored and Government-Guaranteed Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Private Label Mortgage-Backed Securities [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Municipal Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	'	'
Assets Measured at Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Corporate Bonds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Available-for-sale Securities, Fair Value, Total	$1,880	$1,934

Fair_Values_of_Assets_and_Liab3

Fair Values of Assets and Liabilities - Changes in Level 3 Recurring Fair Value of Financial Instruments (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Balance at beginning of year	$1,934
Change in unrealized gain	-54
Balance at end of year	$1,880

Fair_Values_of_Assets_and_Liab4

Fair Values of Assets and Liabilities - Fair Value Hierarchy Used to Determine Adjustment and Carrying Value of Related Individual Assets (Detail) (Fair Value Measurements Nonrecurring [Member], USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Gains (Losses) on fair value of Assets	$57	($287)	($700)	($347)
Level 1 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Level 2 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Level 3 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	1,425	2,387	1,425	2,387
Loans [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Gains (Losses) on fair value loans and other real estate owned	57	-116	-565	-126
Loans [Member] | Level 1 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Loans [Member] | Level 2 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Loans [Member] | Level 3 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	714	722	714	722
Other Real Estate Owned [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Gains (Losses) on fair value loans and other real estate owned	'	-134	-135	-184
Other Real Estate Owned [Member] | Level 1 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Other Real Estate Owned [Member] | Level 2 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Other Real Estate Owned [Member] | Level 3 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	711	1,070	711	1,070
Other Assets [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Gains (Losses) on fair value loans and other real estate owned	'	-37	'	-37
Other Assets [Member] | Level 1 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Other Assets [Member] | Level 2 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	'	'	'
Other Assets [Member] | Level 3 [Member]	'	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'	'
Assets, Fair Value	'	$595	'	$595

Fair_Values_of_Assets_and_Liab5

Fair Values of Assets and Liabilities - Fair Values of Financial Instruments (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financial Assets:	'	'
Securities available for sale	$264,423	$294,322
Securities held to maturity	99,393	85,674
Carrying Value [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	58,960	30,679
Securities available for sale	264,423	294,322
Securities held to maturity	97,991	82,986
Stock in Federal Home Loan Bank of Boston	17,334	18,554
Net loans and loans held for sale	1,882,508	1,808,033
Financial Liabilities:	'	'
Deposits (with no stated maturity)	1,210,921	1,140,766
Time deposits	735,477	707,409
Federal Home Loan Bank of Boston advances	151,029	141,525
Repurchase agreements	60,446	69,229
Subordinated debentures	5,933	9,630
Estimated Fair Value [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	58,960	30,679
Securities available for sale	264,423	294,322
Securities held to maturity	99,393	85,674
Stock in Federal Home Loan Bank of Boston	17,334	18,554
Net loans and loans held for sale	1,887,816	1,846,519
Financial Liabilities:	'	'
Deposits (with no stated maturity)	1,210,921	1,140,766
Time deposits	740,330	711,845
Federal Home Loan Bank of Boston advances	153,706	145,543
Repurchase agreements	60,967	70,082
Subordinated debentures	5,933	9,630
Level 1 [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	58,960	30,679
Securities available for sale	'	'
Securities held to maturity	'	'
Stock in Federal Home Loan Bank of Boston	'	'
Net loans and loans held for sale	'	'
Financial Liabilities:	'	'
Deposits (with no stated maturity)	'	'
Time deposits	'	'
Federal Home Loan Bank of Boston advances	'	'
Repurchase agreements	'	'
Subordinated debentures	'	'
Level 2 [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	'	'
Securities available for sale	262,543	292,388
Securities held to maturity	99,393	85,674
Stock in Federal Home Loan Bank of Boston	'	'
Net loans and loans held for sale	'	'
Financial Liabilities:	'	'
Deposits (with no stated maturity)	'	'
Time deposits	'	'
Federal Home Loan Bank of Boston advances	'	'
Repurchase agreements	'	'
Subordinated debentures	5,933	9,630
Level 3 [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	'	'
Securities available for sale	1,880	1,934
Securities held to maturity	'	'
Stock in Federal Home Loan Bank of Boston	17,334	18,554
Net loans and loans held for sale	1,887,816	1,846,519
Financial Liabilities:	'	'
Deposits (with no stated maturity)	1,210,921	1,140,766
Time deposits	740,330	711,845
Federal Home Loan Bank of Boston advances	153,706	145,543
Repurchase agreements	60,967	70,082
Subordinated debentures	'	'

Pension_and_Postretirement_Ben2

Pension and Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
SERP [Member]	'	'	'	'
Periodic benefit cost:	'	'	'	'
Service cost	$101	$78	$301	$236
Interest cost	47	44	141	132
Total pension cost	148	122	442	368
Prior service cost amortization	50	29	150	86
Net loss amortization	'	'	'	'
Net periodic benefit cost	198	151	592	454
Director Retirement Plan [Member]	'	'	'	'
Periodic benefit cost:	'	'	'	'
Service cost	14	24	41	70
Interest cost	11	14	33	42
Total pension cost	25	38	74	112
Prior service cost amortization	10	9	32	27
Net loss amortization	12	2	36	8
Net periodic benefit cost	$47	$49	$142	$147