Intervest Bancshares (IBCA) 10-K 3 Mar 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Jan. 31, 2014	Jun. 28, 2013
Document And Entity Information [Abstract]	'	'	'
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Entity Registrant Name	'INTERVEST BANCSHARES CORP	'	'
Entity Central Index Key	'0000927807	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	22,012,390	'
Entity Public Float	'	'	$129,958,111

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
ASSETS	'	'
Cash and due from banks	$16,689	$57,641
Federal funds sold and other short-term investments	8,011	2,754
Total cash and cash equivalents	24,700	60,395
Time deposits with banks	5,370	5,170
Securities available for sale, at estimated fair value	965	1,000
Securities held to maturity (estimated fair value of $378,507 and $442,166, respectively)	383,937	443,777
Federal Reserve Bank and Federal Home Loan Bank stock, at cost	8,244	8,151
Loans receivable (net of allowance for loan losses of $27,833 and $28,103, respectively)	1,099,689	1,079,363
Accrued interest receivable	4,861	5,191
Loan fees receivable	2,298	3,108
Premises and equipment, net	4,056	3,878
Foreclosed real estate (net of valuation allowance of $2,017 and $5,339, respectively)	10,669	15,923
Deferred income tax asset	18,362	29,234
Other assets	4,645	10,602
Total assets	1,567,796	1,665,792
Deposits:	'	'
Noninterest-bearing demand deposit accounts	5,211	5,130
Interest-bearing deposit accounts:	'	'
Checking (NOW) accounts	17,831	15,185
Savings accounts	10,027	9,601
Money market accounts	367,384	395,825
Certificate of deposit accounts	881,779	936,878
Total deposit accounts	1,282,232	1,362,619
Long-term debt - subordinated debentures (capital securities)	56,702	56,702
Accrued interest payable on long term debt	868	6,228
Accrued interest payable on deposits	1,508	2,379
Mortgage escrow funds payable	18,879	17,743
Official checks outstanding	7,335	7,003
Other liabilities	3,281	2,171
Total liabilities	1,370,805	1,454,845
Commitments and contingencies (notes 5, 9, 16, 17 and 18)	'	'
STOCKHOLDERS' EQUITY	'	'
Preferred stock ($1.00 par value; 300,000 shares authorized; 25,000 shares issued and outstanding at December 31, 2012)	'	25
Additional paid-in-capital, preferred	'	24,975
Preferred stock discount	'	-376
Common stock ($1.00 par value; 62,000,000 shares authorized; 21,918,623 and 21,589,589 shares issued and outstanding, respectively)	21,919	21,590
Additional paid-in-capital, common	88,043	85,726
Unearned compensation on restricted common stock awards	-1,898	-715
Retained earnings	88,959	79,722
Accumulated other comprehensive loss	-32	'
Total stockholders' equity	196,991	210,947
Total liabilities and stockholders' equity	$1,567,796	$1,665,792

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified
Statement Of Financial Position [Abstract]	'	'
Securities held to maturity, estimated fair value	$378,507	$442,166
Loans receivable, allowance for loan losses	27,833	28,103
Foreclosed real estate, valuation allowance	$2,017	$5,339
Preferred stock, par value	$1	$1
Preferred stock, shares authorized	300,000	300,000
Preferred stock, issued	'	25,000
Preferred stock, outstanding	'	25,000
Common stock, par value	$1	$1
Common stock, shares authorized	62,000,000	62,000,000
Common stock, shares issued	21,918,623	21,589,589
Common stock, shares outstanding	21,918,623	21,589,589

Consolidated_Statements_of_Ear

Consolidated Statements of Earnings (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
INTEREST AND DIVIDEND INCOME	'	'	'
Loans receivable	$59,074	$69,679	$81,185
Securities	4,473	7,559	11,633
Other interest-earning assets	69	46	19
Total interest and dividend income	63,616	77,284	92,837
INTEREST EXPENSE	'	'	'
Deposits	25,430	35,831	47,582
Subordinated debentures - capital securities	1,679	1,848	2,072
FHLB advances and all other borrowed funds	1	388	886
Total interest expense	27,110	38,067	50,540
Net interest and dividend income	36,506	39,217	42,297
(Credit) provision for loan losses	-550	'	5,018
Net interest and dividend income after (credit) provision for loan losses	37,056	39,217	37,279
NONINTEREST INCOME	'	'	'
Income from the early repayment of mortgage loans	2,590	5,134	2,516
Income from mortgage lending activities	1,467	1,169	1,507
Customer service fees	372	473	441
Impairment write downs on investment securities	-964	-582	-201
Gain from sale of securities available for sale	1,481	'	'
All other	'	'	45
Total noninterest income	4,946	6,194	4,308
NONINTEREST EXPENSES	'	'	'
Salaries and employee benefits	7,458	7,122	6,619
Stock compensation for employees and directors	823	1,194	326
Occupancy and equipment, net	2,184	2,059	1,779
FDIC insurance	1,451	2,352	3,045
Professional fees and services	1,407	1,576	1,657
General insurance	618	579	560
Data processing	355	370	416
Director and committee fees	353	413	415
Stationery, printing, supplies, postage and delivery	287	266	253
Real estate activities (income) expense, net	-836	2,146	1,619
Provision for real estate losses	1,105	4,068	3,349
Loss on early extinguishment of debt	'	177	'
All other	648	560	791
Total noninterest expenses	15,853	22,882	20,829
Earnings before provision for income taxes	26,149	22,529	20,758
Provision for income taxes	11,655	10,307	9,512
Net earnings	14,494	12,222	11,246
Preferred stock dividend requirements and discount amortization	1,057	1,801	1,730
Net earnings available to common stockholders	$13,437	$10,421	$9,516
Basic earnings per common share	$0.61	$0.48	$0.45
Diluted earnings per common share	$0.61	$0.48	$0.45
Cash dividends per common share	'	'	'

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement Of Income And Comprehensive Income [Abstract]	'	'	'
Net earnings	$14,494	$12,222	$11,246
Other Comprehensive Loss:	'	'	'
Net unrealized holding losses on available-for-sale securities	-56	'	'
Credit for income taxes related to unrealized losses on available-for-sale securities	24	'	'
Other comprehensive loss, net of tax	-32	'	'
Total comprehensive income, net of tax	$14,462	$12,222	$11,246

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' Equity (USD $)	Total	Preferred Stock [Member]	Additional Paid-In-Capital, Preferred [Member]	Preferred Stock Discount [Member]	Reconciliation of Common Shares Outstanding [Member]	Additional Paid-In-Capital, Common [Member]	Unearned Compensation - Restricted Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
In Thousands, except Share data
Balance at beginning of year at Dec. 31, 2010	'	$25	$24,975	($1,148)	$21,126	$84,705	($749)	$57,026	'
Balance at beginning of year (in shares) at Dec. 31, 2010	'	'	'	'	21,126,489	'	'	'	'
Total stockholders' equity	197,531	25	24,975	-762	21,125	84,765	-483	67,886	'
Net earnings	11,246	'	'	'	'	'	'	11,246	'
Amortization of preferred stock discount	'	'	'	386	'	'	'	'	'
Total preferred stockholder's equity at end of year	24,238	'	'	'	'	'	'	'	'
Amortization of unearned compensation to stock compensation expense	'	'	'	'	'	'	266	'	'
Total common stockholders' equity at end of year	173,293	'	'	'	'	'	'	'	'
Forfeitures of shares of restricted stock	'	'	'	'	-1	-2	'	'	'
Total stockholders' equity at end of year	197,531	25	24,975	-762	21,125	84,765	-483	67,886	'
Preferred stock discount amortization	-1,730	'	'	'	'	'	'	-386	'
Compensation expense related to stock option awards	'	'	'	'	'	62	'	'	'
Issuance (forfeitures) of shares of restricted stock, net	'	'	'	'	-1,200	'	'	'	'
Balance at end of year at Dec. 31, 2011	197,531	25	24,975	-762	21,125	84,765	-483	67,886	'
Balance at end of year (in shares) at Dec. 31, 2011	'	'	'	'	21,125,289	'	'	'	'
Total stockholders' equity	210,947	'	'	-376	21,590	85,726	-715	79,722	'
Issuance of shares of restricted stock	'	'	'	'	466	884	-1,350	'	'
Net earnings	12,222	'	'	'	'	'	'	12,222	'
Amortization of preferred stock discount	'	'	'	386	'	'	'	'	'
Total preferred stockholder's equity at end of year	24,624	'	'	'	'	'	'	'	'
Amortization of unearned compensation to stock compensation expense	'	'	'	'	'	'	1,118	'	'
Total common stockholders' equity at end of year	186,323	'	'	'	'	'	'	'	'
Forfeitures of shares of restricted stock	'	'	'	'	-1	-2	'	'	'
Total stockholders' equity at end of year	210,947	'	'	-376	21,590	85,726	-715	79,722	'
Preferred stock discount amortization	-1,801	'	'	'	'	'	'	-386	'
Compensation expense related to stock option awards	'	'	'	'	'	79	'	'	'
Issuance of shares upon exercise of stock options	100	'	'	'	100	'	'	'	'
Issuance (forfeitures) of shares of restricted stock, net	'	'	'	'	464,200	'	'	'	'
Balance at end of year at Dec. 31, 2012	210,947	25	24,975	-376	21,590	85,726	-715	79,722	'
Balance at end of year (in shares) at Dec. 31, 2012	'	'	'	'	21,589,589	'	'	'	'
Total stockholders' equity	196,991	'	'	'	21,919	88,043	-1,898	88,959	-32
Issuance of shares of restricted stock	'	'	'	'	466	1,999	-2,465	'	'
Net earnings	14,494	'	'	'	'	'	'	14,494	'
Repurchase and redemption of preferred stock	'	-25	-24,975	'	'	'	'	'	'
Amortization of preferred stock discount	'	'	'	376	'	'	'	'	'
Net change in accumulated other comprehensive loss, net of tax	-32	'	'	'	'	'	'	'	-32
Issuance of shares upon exercise of stock options	'	'	'	'	17	44	'	'	'
Cash dividends declared and paid on preferred stock	'	'	'	'	'	'	'	-5,068	'
Amortization of unearned compensation to stock compensation expense	'	'	'	'	'	'	1,282	'	'
Total common stockholders' equity at end of year	196,991	'	'	'	'	'	'	'	'
Forfeitures of shares of restricted stock	'	'	'	'	-154	-348	'	'	'
Discount from repurchase of preferred stock	'	'	'	'	'	'	'	187	'
Total stockholders' equity at end of year	196,991	'	'	'	21,919	88,043	-1,898	88,959	-32
Excess income tax benefit from vesting of restricted stock and exercise of stock options	'	'	'	'	'	579	'	'	'
Preferred stock discount amortization	-1,057	'	'	'	'	'	'	-376	'
Compensation expense related to stock option awards	'	'	'	'	'	43	'	'	'
Issuance of shares upon exercise of stock options	17,267	'	'	'	17,267	'	'	'	'
Issuance (forfeitures) of shares of restricted stock, net	'	'	'	'	311,767	'	'	'	'
Balance at end of year at Dec. 31, 2013	$196,991	'	'	'	$21,919	$88,043	($1,898)	$88,959	($32)
Balance at end of year (in shares) at Dec. 31, 2013	'	'	'	'	21,918,623	'	'	'	'

Consolidated_Statements_of_Cha1

Consolidated Statements of Changes in Stockholders' Equity (Parenthetical)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Issuance of shares upon exercise of stock options, shares	17,267	100	'
Reconciliation of Common Shares Outstanding [Member]	'	'	'
Issuance of shares of restricted stock, shares	466,200	465,400	'
Issuance of shares upon exercise of stock options, shares	17,267	100	'
Forfeitures of shares of restricted stock issued, shares	154,433	1,200	1,200
Unearned Compensation - Restricted Common Stock [Member]	'	'	'
Issuance of shares of restricted stock, shares	466,200	465,400	'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
OPERATING ACTIVITIES	'	'	'
Net earnings	$14,494	$12,222	$11,246
Adjustments to reconcile net earnings to net cash provided by operating activities:	'	'	'
Depreciation and amortization	353	345	357
Provisions for loan and real estate losses	555	4,068	8,367
Deferred income tax expense	10,896	9,602	8,243
Stock compensation expense	823	1,194	326
Amortization of deferred debenture offering costs	37	37	37
Amortization of premiums (accretion) of discounts and deferred loan fees, net	635	395	-1,448
Net gain from sale of securities available for sale	-1,481	'	'
Impairment writedowns on investment securities	964	582	201
Net (gains) losses from sales of or transfers of loans to foreclosed real estate	-963	93	-188
Net gain from sale of premises	'	'	-44
Net loss from early extinguishment of debt	'	177	'
Net decrease in loan fees receivable	810	1,080	1,282
Net (decrease) increase in accrued interest payable on borrowed funds	-5,360	1,867	2,099
Net increase (decrease) in official checks outstanding	332	2,003	-1,605
Net change in all other assets and liabilities	8,507	3,506	17,244
Net cash provided by operating activities	30,602	37,171	46,117
INVESTING ACTIVITIES	'	'	'
Purchases of time deposits with banks	-200	-3,700	-1,470
Purchases of securities available for sale	-21	-1,000	'
Proceeds from sale of securities available for sale	4,050	'	'
Purchases of securities held to maturity	-76,124	-438,671	-894,680
Maturities and calls of securities held to maturity	130,209	692,193	807,038
(Purchases) redemptions of FRB and FHLB stock, net	-93	1,098	406
(Originations) repayments of loans receivable, net	-20,007	53,643	161,592
Proceeds from sales of foreclosed real estate	4,912	8,749	'
Proceeds from sales of premises	'	'	379
Purchases of premises and equipment	-531	-119	-184
Net cash provided by investing activities	42,195	312,193	73,081
FINANCING ACTIVITIES	'	'	'
Net decrease in deposits	-80,387	-299,405	-104,059
Net increase (decrease) in mortgage escrow funds payable	1,136	-1,927	-1,039
Net decrease in FHLB advances - original terms of more than 3 months	'	-17,500	-8,000
Principal repayments of mortgage note payable	'	'	-148
Repurchase and redemption of preferred stock	-24,813	'	'
Cash dividends paid to preferred stockholders	-5,068	'	'
Proceeds from issuance of common stock upon exercise of stock options	61	'	'
Excess tax benefit from exercise of stock options and vesting of restricted stock	579	'	'
Net cash used in financing activities	-108,492	-318,832	-113,246
Net (decrease) increase in cash and cash equivalents	-35,695	30,532	5,952
Cash and cash equivalents at beginning of year	60,395	29,863	23,911
Cash and cash equivalents at end of year	24,700	60,395	29,863
SUPPLEMENTAL DISCLOSURES	'	'	'
Cash paid for interest	33,304	37,503	49,342
Cash paid for (received from refunds of) income taxes, net	940	734	-10,340
Loans transferred to foreclosed real estate	3,040	4,689	4,375
Loans originated to finance sales of foreclosed real estate	3,240	4,134	'
Preferred stock dividend requirements and amortization of related discount	1,801	1,801	1,730
Securities held to maturity transferred to securities available for sale	$2,569	'	'

Description_of_Business_and_Su

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Description of Business and Summary of Significant Accounting Policies	'
	1. Description of Business and Summary of Significant Accounting Policies
	Intervest Bancshares Corporation (IBC) is a bank holding company incorporated in 1993 under the laws of the State of Delaware and its common stock trades on the Nasdaq Global Select Market under the symbol IBCA. IBC is the parent company of Intervest National Bank (INB) and IBC owns 100% of its capital stock. IBC’s primary purpose is the ownership of INB. It does not engage in any other business activities other than, from time to time, a limited amount of real estate mortgage lending, including the participation in loans originated by INB. IBC also may issue debt and equity securities as needed to raise funds for working capital purposes.
	IBC also owns 100% of the capital stock of four statutory business trusts (Intervest Statutory Trust II, III, IV and V, the “Trusts”), all of which are unconsolidated entities for financial statement purposes. The Trusts do not conduct business and were formed prior to 2006 for the sole purpose of issuing and administering trust preferred securities and lending the proceeds to IBC.
	References to “we,” “us” and “our” in this report refer to IBC and INB on a consolidated basis, unless otherwise specified. The offices of IBC and INB’s headquarters and full-service banking office are located on the entire fourth floor of One Rockefeller Plaza in New York City, New York, 10020-2002. The main telephone number is 212-218-2800.
	Our business is banking and real estate lending conducted through INB’s operations. INB is a nationally chartered commercial bank that opened for business on April 1, 1999 and accounts for 99% of our consolidated assets. In addition to its headquarters and full-service banking office in Rockefeller Plaza in New York City, INB has a total of six full-service banking offices in Pinellas County, Florida - four in Clearwater, one in Clearwater Beach and one in South Pasadena. INB also has an ownership interest in a number of limited liability companies whose sole purpose is to own title to real estate that INB may acquire through foreclosure. INB conducts a personalized commercial and consumer banking business that attracts deposits from the general public. It also provides internet banking services through its web site www.intervestnatbank.com. INB solicits deposit accounts from individuals, small businesses and professional firms located throughout its primary market areas in New York and Florida through the offering of a variety of deposit products and providing online and telephone banking. INB’s web site also attracts deposit customers from both within and outside its primary market areas. INB uses these deposits, together with funds generated from its operations, principal repayments of loans and securities and other sources, to originate mortgage loans secured by commercial and multifamily real estate and to purchase investment securities.
	Principles of Consolidation, Basis of Presentation and Use of Estimates
	The consolidated financial statements in this report (which may also be referred to as “financial statements” throughout this report) include the accounts of IBC and its subsidiary. All significant intercompany balances and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior year amounts to conform to the current year’s presentation. Our accounting and reporting policies conform to Generally Accepted Accounting Principles (“GAAP”) and to general practices within the banking industry.
	In preparing the consolidated financial statements, we are required to make estimates and assumptions that affect the reported amounts of our assets, liabilities and disclosure of our contingent liabilities as of the date of the consolidated financial statements, and revenues and expenses during the reporting periods. Actual results could differ from those estimates. Estimates that are particularly susceptible to significant change currently relate to the determination of our allowance for loan losses, valuation allowance for real estate losses, other than temporary impairment assessments of our security investments and the need for and amount of a valuation allowance for our deferred tax asset. These estimates involve a higher degree of complexity and subjectivity and require assumptions about highly uncertain matters.
	Cash Equivalents
	For purposes of reporting cash flows, our cash equivalents include cash and balances due from banks, federal funds sold (generally sold for one-day periods) and other short-term investments that have maturities of three months or less from the time of purchase.
	Securities
	General. Investments in debt securities for which we have the ability and intent to hold until maturity are classified as held to maturity (“HTM”) and are carried at cost, adjusted for accretion of discounts and amortization of premiums, which are recognized into interest income using the effective interest method over their contractual lives. Securities that are held for indefinite periods of time which we intend to use as part of our asset/liability management strategy, or that may be sold in response to changes in interest rates or other factors, are classified as available for sale (“AFS”) and are carried at fair value. Unrealized gains and losses on securities available for sale, net of related income taxes, are reported as a separate component of comprehensive income. Realized gains and losses from sales of securities are determined using the specific identification method. We do not purchase securities for the purpose of engaging in trading activities.
	Impairment. We evaluate our security investments for other than temporary impairment (“OTTI”) at least quarterly or more frequently when conditions warrant such evaluation. Impairment is assessed at the individual security level. We consider an investment security to be impaired if, after a review of available evidence, the full collection of our principal investment and interest over the life of the security is no longer probable. The assessment for and the amount of impairment requires the exercise of considerable judgment by us and is entirely an estimate and not a precise determination.
	Our impairment evaluation process considers factors such as the expected cash flows of the security, severity, length of time and anticipated recovery period of the cash shortfalls, recent events specific to the issuer, including investment downgrades by rating agencies and current and anticipated economic and regulatory conditions of its industry, and the issuer’s financial condition, capital strength and near-term prospects. We also consider our intent and ability to retain the security for a period of time sufficient to allow for a recovery in fair value, or until maturity. Among the factors that we consider in determining our intent and ability to retain the security is a review of our capital adequacy, interest rate risk position and liquidity. If it is deemed that OTTI has occurred, the security is written down to a new cost basis and the resulting loss is charged to operations as a component of noninterest income.
	INB is a member of the Federal Home Loan Bank of New York (FHLB) and Federal Reserve Bank of New York (FRB) and is required hold a certain level capital stock of each entity based on various criteria. These investments are carried at cost and are also periodically reviewed for OTTI.
	Loans Receivable
	General. Loans for which we have the intent and ability to hold for the foreseeable future or until maturity or satisfaction are carried at their outstanding principal net of chargeoffs, the allowance for loan losses, unamortized discounts and deferred loan fees or costs. Loan origination and commitment fees, net of certain costs, are deferred and amortized to interest income as an adjustment to the yield of the related loans over the contractual life of the loans using the interest method. When a loan is paid off or sold, or if a commitment expires unexercised, any unamortized net deferred amount is credited or charged to operations.
	Loans are placed on nonaccrual status when principal or interest becomes 90 days or more past due or earlier in certain cases unless the loan is well secured and in the process of collection. Past due status is based on contractual terms of the loan. When a loan is placed on nonaccrual status, all interest accrued but not collected is reversed against interest income and amortization of net deferred fee income is discontinued. Interest payments received on loans in nonaccrual status are recognized as income on a cash basis unless future collections of principal are doubtful, in which case the payments received are applied as a reduction of principal.
	Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured. For loans that have been partially charged off, if the remaining book balance of the loan is deemed fully collectible, interest income is recognized on a cash basis but limited to that which would have been accrued on the recorded balance at the contractual rate. Any cash interest received over this limit is recorded as recoveries of prior charge offs until these chargeoffs have been fully recovered.
	Segments. We consider our loan portfolio to be comprised of two segments - (i) real estate loans (which is comprised of loans secured by commercial real estate and multifamily (5 or more units) real estate, loans secured by vacant land and loans secured by 1-4 family real estate) and (ii) all other loans (which is comprised of personal and business loans, both secured and unsecured). Each segment has different risk characteristics and methodologies for assessing risk.
	Commercial and multifamily real estate loans are generally considered to have more credit risk than traditional single family residential loans because these loans tend to involve larger loan balances and their repayment is typically dependent upon the successful operation and management of the underlying real estate. Included in this category are loans we originate on vacant or substantially vacant properties and owner-occupied properties, all of which typically have limited or no income streams and depend upon other sources of cash flow from the borrower for repayment, which add an additional element of risk. Our land loans normally have no income streams and depend upon other sources of cash flow from the borrower for repayment. Our 1-4 family loans consist almost entirely of loans secured by individual condominium dwelling units. We normally make these loans to investors who purchase multiple condo units that remain unsold after a condo conversion or the unsold units in a new condo development. The units are normally rented for a number of years until the economy improves and the units can be sold as was the original intention. Nearly all of these loans are in our Florida market. Although these loans are classified necessarily as loans secured by 1-4 family real estate as required by regulatory guidance, they are underwritten in accordance with our multifamily underwriting polices and their risk characteristics are essentially the same as our multifamily real estate lending and we risk weight them for regulatory capital purposes at 100%. All the above loans require ongoing evaluation and monitoring since they may be affected to a greater degree by adverse conditions in the real estate markets or the economy or changes in government regulation.
	Our real estate loans typically provide for periodic payments of interest and principal during the term of the loan, with the remaining principal balance and any accrued interest due at the maturity date. Most of these loans provide for balloon payments at maturity, which means that a substantial part of or the entire original principal amount is due in one lump sum payment at maturity. If the net revenue from the property is not sufficient to make all debt service payments due on the loan or, if at maturity or the due date of any balloon payment, the owner of the property fails to raise the funds (through refinancing the loan, sale of the property or otherwise) to make the lump sum payment, we could sustain a loss on our loan. As part of our written policies for real estate loans, loan-to-value ratios (the ratio that the original principal amount of the loan bears to the lower of the purchase price or appraised value of the property securing the loan at the time of origination) on loans originated by us typically do not exceed 80% and in practice, rarely exceed 75%. Debt service coverage ratios (the ratio of the net operating income generated by the property securing the loan to the required debt service) on multi-family and commercial real estate loans originated typically are not less than 1.2 times. As noted earlier, we may originate mortgage loans on vacant or substantially vacant properties and vacant land for which there is limited or no cash flow being generated by the operation of the underlying real estate. We may also require personal guarantees from the principals of our borrowers as additional security, although loans are often originated on a limited recourse basis. In originating loans, we consider the ability of the net operating income generated by the real estate to support the debt service, the financial resources, income level and managerial expertise of the borrower, the marketability of the property and our lending experience with the borrower. Our loans are not insured or guaranteed by governmental agencies. In the event of a default, our ability to recover our investment is dependent upon the market value of the mortgaged property.
	The “all other loans” segment is comprised of a small number of business and consumer loans that are extended for various purposes, including lines of credit, personal loans, and personal loans collateralized by deposit accounts. Repayment of consumer loans is primarily dependent on the personal income of the borrowers, which can be impacted by economic conditions in their market areas such as unemployment levels. Loans to businesses and consumers are extended after a credit evaluation, including the creditworthiness of the borrower, the purpose of the credit, and the secondary source of repayment. Risk is mitigated somewhat by the fact that the loans are of smaller individual amounts.
	Risk ratings. We categorize our loans into various risk categories (discussed below) based on an individual analysis of each loan’s quantitative factors and other relevant information, including: an analysis of the underlying collateral’s appraised value and its actual cash flows, with emphasis on projected or normalized cash flows in cases where the collateral currently has no or inadequate cash flows to service the debt; the ability of the borrowers to service their debt from other sources, including whether they have personally guaranteed the loan and the strength of that guaranty, which takes into account a review of their current personal financial information; credit and loan underwriting documentation; and other available pertinent information about the borrower or the collateral, such as an annual property inspection. All of our loans are assigned a risk grade upon based on the timely review, interpretation of and conclusions on the above data as received by us.
	Loans are normally classified as pass credits until they become past due or management becomes aware of deterioration in cash flows and or the credit worthiness of the collateral or the borrower based on the information we collect and monitor. All of our pass-rated loans our generally reviewed annually to determine if they are appropriately classified. Loans rated substandard or special mention are reviewed at least quarterly or more often in some cases to determine if they are appropriately classified. Further, during the renewal process of any maturing loan, as well as if any loan becomes past due, the loan’s risk rating is also reviewed for appropriateness.
	Our internally assigned risk grades and a general summary of the factors that determine the ratings are as follows:
	Pass – Loan is normally current and its primary source of repayment is satisfactory, with secondary sources adequate and very likely to be realized if necessary. This category also contains loans where the underlying collateral is not producing cash flows or is producing in-adequate cash flows to service the loan’s required payments (such as in cases where the collateral is a vacant or substantially vacant building or land) and such payments are being made by the borrower’s other sources of funds. In many cases, the borrower or its principals has guaranteed the loan and or deposited escrow funds with us to cover the loan’s contractual payments for a portion of the loan term.
	Special Mention – Loan is normally current but has one or more potential weaknesses that deserve close attention. If left uncorrected, these potential weaknesses may result in the deterioration of the loan’s repayment prospects or our credit position at some future date.
	Substandard – Loan is inadequately protected by the current worth and paying capacity of the borrower or of the underlying collateral. Such loans have a well-defined weakness or weaknesses that jeopardize the full repayment of the loan. These loans have the distinct possibility that we will sustain some loss if the deficiencies are not corrected.
	Doubtful – Loan has all the weaknesses inherent in one classified substandard with the added characteristics that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable.
	Loss – Loan is considered uncollectible and of such little value that continuance as an asset is not warranted. This classification does not mean that the asset has absolutely no recovery or salvage value, but rather it is not practical or desirable to defer writing off this basically worthless asset even though partial recovery may be occur in the future.
	Restructured Loans (TDRs). A TDR is a loan that we have restructured, for economic or legal reasons related to a borrower’s financial difficulties, and for which we have granted certain concessions to the borrower that we would not otherwise have considered. In order to be considered a TDR, we must conclude that the restructuring was to a borrower who is experiencing financial difficulties and the restructured loan constitutes a “concession”. We define a concession as a modification of existing terms granted to a borrower for economic or legal reasons related to the borrower’s financial difficulties. Concessions include modifying the original loan terms to reduce or defer cash payments required as part of the loan agreement, including but not limited to: a reduction of the stated interest rate for the remaining original life of the debt; an extension of the maturity date or dates at an interest rate lower than the current market rate for new debt with similar risk characteristics, a reduction of the face amount or maturity amount of the debt, or a reduction of accrued interest owed on the debt. A loan that is extended or renewed at a stated interest rate equal to the current interest rate for a new loan originated by us with similar risk is not reported as a TDR.
	In determining whether the borrower is experiencing financial difficulties, we consider, among other things, whether the borrower is in default on its existing loan, or is in an economic position where it is probable the borrower will be in default on its loan in the foreseeable future without a modification, including whether, without the modification, the borrower cannot obtain sufficient funds from other sources at an effective interest rate equal to the current market rate for similar debt for a non-troubled debtor. TDR loans are reviewed for specific impairment in accordance with our allowance for loan loss methodology with respect to impaired loans. A TDR that is on nonaccrual status is returned to an accrual status if ultimate collectability of the entire contractual principal is assured and the borrower has demonstrated satisfactory payment performance either before or after the restructuring, usually consisting of a six-month period.
	Impaired Loans. Loans are deemed to be impaired when, based upon current information and events, it is probable that we will be unable to collect both principal and interest due according to the loan’s contractual terms. We consider a variety of factors in determining whether a loan is impaired, including (i) any notice from the borrower that the borrower will be unable to repay all principal and interest amounts contractually due under the loan agreement, (ii) any delinquency in the principal and/or interest payments other than minimal delays or shortfalls in payments, and (iii) other information known by us that would indicate the full repayment of principal and interest is not probable. We generally consider delinquencies of 60 days or less to be minimal delays, and accordingly we do not consider such delinquent loans to be impaired in the absence of other indications.
	Our impaired loans normally consist of loans on nonaccrual status and TDRs. Generally, impairment for all of our impaired loans is calculated on a loan-by-loan basis using either the estimated fair value of the loan’s collateral less estimated selling costs (for collateral dependent loans) or the present value of the loan’s cash flows (for non-collateral dependent loans). Any calculated impairment is recognized as a valuation allowance within the overall allowance for loan losses and a charge through the provision for loan losses. We may charge off any portion of the impaired loan with a corresponding decrease to the valuation allowance when such impairment is deemed uncollectible and confirmed as a loss. The net carrying amount of an impaired loan (net of the valuation allowance) does not at any time exceed the recorded investment in the loan.
	Allowance for Loan Losses and Loan Chargeoffs
	The allowance for loan losses, which includes a valuation allowance for impaired loans, is netted against loans receivable and is increased by provisions charged to operations and decreased by chargeoffs (net of recoveries). The adequacy of the allowance is evaluated at least quarterly with consideration given to various factors beginning with our historical lending loss rate for each major loan type (exclusive of the impact of any transaction that is unusual and deemed not reflective of normal charge-off history).
	The historical loss rate is then adjusted either upward or downward based on a review of the following qualitative factors and their estimated impact to the historical loss rate: (i) the size of our loans; (ii) concentrations of our loans; (iii) changes in the quality of our review of specific problem loans, including loans on nonaccrual status, and estimates of fair value of the underlying properties; (iv) changes in the volume of our past due loans, nonaccrual loans and adversely classified assets. (iv) specific problem loans and estimates of fair value of the related collateral; (v) adverse situations which may affect our borrowers’ ability to repay; (vi) changes in national, regional and local economic and business conditions and other developments that may affect the collectability of our loan portfolio, including impacts of political, regulatory, legal and competitive changes on the portfolio; (vii) changes to our lending policies and procedures, underwriting standards, risk selection (loan volumes and loan terms) and to our collection, loan chargeoff and recovery practices; and (viii) changes in the experience, ability and depth of our lending management and other relevant staff.
	We fully or partially charge off an impaired loan when such amount has been deemed uncollectible and confirmed as a loss. In the case of impaired collateral dependent loans, we normally charge-off the portion of the loan’s recorded investment that exceeds the appraised value (net of estimated selling costs) of its underlying collateral. The remaining portion of the valuation allowance that we have provided and maintain on all of our impaired loans for the difference between the net appraised value and our internal estimate of fair value of the collateral is charged off only when such amount has been confirmed as a loss, either through the receipt of future appraisals or through our quarterly evaluation of the factors described below.
	Consistent with regulatory guidance, we normally maintain a specific valuation allowance on each of our impaired loans. We believe it is prudent to do so because the process of estimating real estate values is imprecise and subject to changing market conditions which could cause fluctuations in estimated values. Estimates are subjective in nature, involve uncertainties and matters of significant judgment and therefore, cannot be determined with precision. Changes in any of the market assumptions could cause fair value estimates to deviate substantially. Furthermore, commercial real estate markets and national and local economic conditions remain weak; unemployment rates and vacancy rates in retail and office properties continue to be high; and the timing of the resolution of impaired loans in many cases remains uncertain, which increases the negative impact to the portfolio from further declines in real estate values.
	Regulatory guidelines require that the appraised value of collateral should be used as a starting point for determining its estimated fair value. An institution should also consider other factors and events in the environment that may affect the current fair value of the collateral since the appraisal was performed. The institution’s experience with whether the appraised values of impaired collateral-dependent loans are actually realized should also be taken into account. In addition, the timing of when the cash flows are expected to be received from the underlying collateral could affect the fair value of the collateral if the timing was not contemplated in the appraisal. The consideration of all the above generally results in the appraised value of the collateral being greater than the institution’s estimate of the collateral’s fair value, less estimated costs to sell. As a consequence, an institution may necessarily still have a specific reserve on an impaired loan (whether or not a charge off has been taken) for the amount by which the institution’s estimated fair value of the collateral, less estimated costs to sell, is believed to be lower than its appraised value. As a result, we maintain a specific valuation allowance on all of our impaired loans for the reasons described above.
	We estimate the fair value of the properties that collateralize our impaired loans based on a variety of information, including third party appraisals and our management’s judgment of other factors. Our internal policy is to obtain externally prepared appraisals as follows (i) for all impaired loans; (ii) for all restructured or renewed loans; (iii) upon classification or downgrade of a loan; (iv) upon completion of foreclosure and acquisition of the collateral property; and at least annually thereafter for all impaired and substandard rated loans and real estate owned through foreclosure.
	In addition, we also consider the knowledge and experience of our two senior lending officers (our Chairman and INB’s President) and INB’s Chief Credit Officer related to values of properties in our lending markets. They take into account various information, including: discussions with real estate brokers and interested buyers, local and national real estate market data provided by third parties; the consideration of the type, condition, location, demand for and occupancy of the specific collateral property and current economic and real estate market conditions in the area the property is located in assessing our internal estimates of fair value.
	Our regulators, as an integral part of their examination process, also periodically review our allowances for loan and real estate losses. Accordingly, we may be required to take chargeoffs and/or recognize additions to these allowances based on the regulators’ judgment concerning information available to them during their examination. There were no changes to our methodology for the allowance for loan loss during the reporting periods in this report.
	Premises and Equipment
	Land is carried at cost. Buildings, leasehold improvements and furniture, fixtures and equipment are carried at cost, less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful life of the asset. Leasehold improvements are amortized using the straight-line method over the terms of the related leases, or the useful life of the asset, whichever is shorter. Maintenance, repairs and minor improvements are expensed as incurred, while major improvements are capitalized.
	Deferred Debenture Offering Costs
	Costs relating to offerings of our debentures consisting primarily of underwriters’ commissions are amortized over the life of the debentures. At December 31, 2013, these costs totaled approximately $0.7 million, net of accumulated amortization of $0.4 million. At December 31, 2012, these costs totaled approximately $0.8 million, net of accumulated amortization of $0.3 million.
	Foreclosed Real Estate and Valuation Allowance For Real Estate Losses
	Real estate that we acquire through loan foreclosure or similar proceedings is held for sale. At the time we acquire the property, the related loan is transferred from the loan portfolio to foreclosed real estate at the estimated fair value of the property less estimated selling costs. Such amount becomes the new cost basis of the property. Adjustments made to reduce the carrying value at the time of transfer are charged to the allowance for loan losses.
	We may periodically adjust the carrying values of the real estate to reflect decreases in its estimated fair value through a charge to earnings (recorded as a provision for real estate losses) and an increase to the valuation allowance for real estate losses. As the properties are sold, the valuation allowance associated with the property, if any, is charged off. We determine the estimated fair value of foreclosed real estate at least quarterly by performing market valuations of the properties, which normally consist of obtaining externally prepared appraisals at least annually for every property, as well as performing reviews of economic and real estate market conditions in the local area where the property is located, including taking into consideration discussions with real estate brokers and interested buyers, in order to determine if a valuation allowance is needed to reflect any decrease in the estimated fair value of the property since acquisition.
	Revenue and expenses from the operations of foreclosed real estate are included in the caption “Real Estate Activities” in the consolidated statements of earnings. This line item is comprised of real estate taxes, repairs and maintenance, insurance, utilities, legal fees and other charges (net of any rental income earned from the operation of the property) that are required in protecting our interest in real estate acquired through foreclosure and various properties collateralizing our nonaccrual loans.
	Stock-Based Compensation
	We recognize the cost of our employee and director services received in exchange for awards of our equity instruments (such as restricted stock and stock options grants) based on the grant-date fair value of the awards. Compensation cost related to the awards is recognized on a straight-line basis over the requisite service period, which is normally the vesting period of the grants. The fair value of options granted is estimated using the Black-Scholes option-pricing model based on various assumptions that are described in note 13. The fair value of restricted stock grants is based on the closing market value of the stock as reported on the Nasdaq Stock Market on the grant date.
	Advertising Costs
	Advertising costs are expensed as incurred and amounted to $23,000 in 2013, $17,000 in 2012 and $26,000 in 2011.
	Income Taxes
	Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of the enacted tax law to our taxable income or loss. Deferred income taxes are recognized for the tax consequences of temporary differences by applying enacted statutory tax rates, applicable to future years, to differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income tax expense in the period that includes the enactment date.
	Deferred tax assets are reduced by a valuation allowance if, based on the weight of evidence available, it is more likely than not that some portion or all of a deferred tax asset will not be realized. Certain tax benefits attributable to stock options, restricted stock and warrants are credited to additional paid-in-capital. Accruals of interest and penalties related to unrecognized tax benefits are recognized in income tax expense.
	Uncertain tax positions are recognized if it is more likely (a likelihood of more than 50 percent) than not that the tax position will be realized or sustained upon examination. A tax position that meets the more-likely-than-not recognition threshold is initially and subsequently measured as the largest amount of tax benefit that has a greater than 50 percent likelihood of being realized upon settlement with a taxing authority. The determination of whether or not a tax position has met the more-likely-than-not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management’s judgment. At December 31, 2013, we were not aware of any uncertain tax positions that would have a material effect on our financial statements.
	Earnings Per Common Share
	Basic earnings per common share is calculated by dividing net earnings available to common stockholders by the weighted-average number of shares of all common stock outstanding during the reporting period. Unvested restricted stock is deemed to be issued and outstanding. Diluted earnings per common share is calculated by dividing net earnings available to common stockholders by the weighted-average number of shares of common stock and dilutive potential common stock shares that may be outstanding in the future. Potential common stock shares consist of shares that may arise from outstanding dilutive common stock warrants and options (the number of which is computed using the “treasury stock method”).
	When applying the treasury stock method, we add: the assumed proceeds from stock option and warrant exercises; the tax benefit that would have been credited to additional paid-in capital assuming exercise of non-qualified stock options and warrants and the unamortized compensation costs related to unvested shares of stock options and warrants. We then divide this sum by our average stock price for the period to calculate shares assumed to be repurchased. The excess of the number of shares issuable over the number of shares assumed to be repurchased is added to basic weighted average common shares to calculate diluted earnings per common share.
Comprehensive Income
Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net earnings. However, certain changes in assets and liabilities, such as unrealized gains and losses on available-for-sale securities, are reported as a separate component of the stockholders’ equity section of the consolidated balance sheet, such items along with net earnings, are components of comprehensive income.
Off-Balance Sheet Financial Instruments
We enter into off-balance sheet financial instruments consisting of commitments to extend credit, unused lines of credit and from time to time standby letters of credit. Such financial instruments are recorded in the consolidated financial statements when they are funded or related fees are received.
Recent Accounting Standards Update
In July 2012, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) 2012-02, “Testing Indefinite-Lived Intangible Assets for Impairment,” which, among other things, gives an entity the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that an indefinite-lived intangible asset is impaired. We adopted this ASU on January 1, 2013, and since we do not have intangible assets, it had no impact on our financial statements.
In January 2013, the FASB issued ASU No. 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities,” which limits the scope of the new balance sheet offsetting disclosures in ASU 2011-11 to derivatives, repurchase agreements, and securities lending transactions to the extent that they are (1) offset in the financial statements or (2) subject to an enforceable master netting arrangement or similar agreement. We adopted this ASU on February 1, 2013 and it had no impact on our financial statements.
In February 2013, the FASB Issued ASU No. 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income,” which requires entities to present information about reclassification adjustments from accumulated other comprehensive income in their annual financial statements in a single note or on the face of the financial statements. We adopted this ASU on March 1, 2013 and it had no impact on our financial statements.
In February 2013, the FASB Issued ASU No. 2013-04, “Obligations Resulting from Joint and Several Liability Arrangements for Which the Total Amount of the Obligation Is Fixed at the Reporting Date”. ASU 2013-04 provides guidance for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for obligations within the scope of this ASU, which is effective January 1, 2014. Upon adoption, we do not expect this ASU to impact our financial statements.
In July 2013, the FASB issued ASU No. 2013-10, “Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes”. ASU No. 2013-10 permits the use of the Fed Funds Effective Swap Rate (OIS) to be used as a U.S. benchmark interest rate for hedge account purposes. The amendment is effective prospectively for qualifying new or re-designated hedging relationships entered into on or after July 17, 2013. The adoption of ASU No. 2013-10 did have an impact on our financial statements.
In July 2013, the FASB issued ASU 2013-11, “Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists,” which among other things, require an unrecognized tax benefit, or a portion of an unrecognized tax benefit, to 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 as denoted within the ASU. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. We are currently evaluating the impact of ASU 2013-11 on our financial statements.

Securities_Held_to_Maturity_an

Securities Held to Maturity and Available for Sale	12 Months Ended
	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]	'
Securities Held to Maturity and Available for Sale	'
	2. Securities Held to Maturity and Available for Sale
	The carrying value (amortized cost) and estimated fair value of securities held to maturity (“HTM”) are as follows:
	($ in thousands)		Number of			Amortized			Gross			Gross		Estimated		Wtd-Avg			Wtd-Avg		Wtd-Avg
			Securities			Cost			Unrealized			Unrealized		Fair		Yield			Expected		Remaining
									Gains			Losses		Value					Life		Maturity
	At December 31, 2013
	U.S. government agencies (1)			161		$	305,906		$	410		$	4,947	$	301,369		0.94	%	3.0 Yrs		3.8 Yrs
	Residential mortgage-backed (2)			57			77,500			130			1,017		76,613		1.79	%	4.3 Yrs		14.7 Yrs
	State and municipal			1			531			—			6		525		1.25	%	3.2 Yrs		3.3 Yrs
				219		$	383,937		$	540		$	5,970	$	378,507		1.11	%	3.3Yrs		6.0 Yrs
	At December 31, 2012
	U.S. government agencies (1)			165		$	355,244		$	1,109		$	233	$	356,120		0.87	%	1.6 Yrs		4.6 Yrs
	Residential mortgage-backed (2)			48			84,279			651			72		84,858		1.76	%	3.3 Yrs		17.3 Yrs
	State and municipal			1			533			—			3		530		1.25	%	4.2 Yrs		4.3 Yrs
	Corporate (3)			8			3,721			—			3,063		658		2.11	%	20.3 Yrs		20.9 Yrs
				222		$	443,777		$	1,760		$	3,371	$	442,166		1.05	%	2.0 Yrs		7.1 Yrs
	-1	Consisted of debt obligations of U.S. government sponsored agencies (GSEs) - Federal Home Loan Bank (FHLB), Federal Farm Credit Bank (FFCB), Federal National Mortgage Association (FNMA) and Federal Home Loan Mortgage Corporation (FHLMC), which are federally chartered corporations privately owned by shareholders. GSE securities carry no explicit U.S. government guarantee of creditworthiness. Neither principal nor interest payments are guaranteed by the U.S. government nor do they not constitute a debt or obligation of the U.S. government or any of its agencies or instrumentalities other than the applicable GSE. FNMA and FHLMC are under U.S. government conservatorship.
	-2	At December 31, 2013, consisted of $13.6 million of Government National Mortgage Association (GNMA) pass-through certificates, $45.6 million of FNMA participation certificates and $18.3 million of FHLMC participation certificates, compared to $18.7 million, $40.0 million and $25.6 million, respectively, at December 31, 2012. The GNMA pass-through certificates are guaranteed as to the payment of principal and interest by the full faith and credit of the U.S. government while the FNMA and FHLMC certificates have an implied guarantee by such agency as to principal and interest payments.
	-3	Consisted of variable-rate pooled trust preferred securities backed by obligations of companies in the banking industry. Amortized cost at December 2012 is reported net of other than temporary impairment (“OTTI”) charges of $4.2 million. During 2013, an additional $1.0 million of OTTI charges were recorded. In December 2013, these securities were transferred to available for sale and subsequently sold.
	The estimated fair values of HTM securities with gross unrealized losses segregated between securities that have been in a continuous unrealized loss position for less than twelve months at the respective dates and those that have been in a continuous unrealized loss position for twelve months or longer are summarized as follows:
	($ in thousands)		Number of			Less Than Twelve Months						Twelve Months or Longer				Total
			Securities			Estimated			Gross			Estimated		Gross		Estimated			Gross
						Fair			Unrealized			Fair		Unrealized		Fair			Unrealized
						Value			Losses			Value		Losses		Value			Losses
	At December 31, 2013
	U.S. government agencies			130		$	233,930		$	4,791		$	7,344	$	156	$	241,274		$	4,947
	Residential mortgage-backed			41			48,862			987			3,284		30		52,146			1,017
	State and municipal			1			525			6			—		—		525			6
				172		$	283,317		$	5,784		$	10,628	$	186	$	293,945		$	5,970
	At December 31, 2012
	U.S. government agencies			53		$	129,365		$	233		$	—	$	—	$	129,365		$	233
	Residential mortgage-backed			14			24,481			72			—		—		24,481			72
	State and municipal			1			530			3			—		—		530			3
	Corporate			8			—			—			658		3,063		658			3,063
				76		$	154,376		$	308		$	658	$	3,063	$	155,034		$	3,371
	At December 31, 2013, all of the securities were investment grade rated. The securities had either fixed interest rates or had predetermined scheduled interest rate increases and nearly all had call or prepayment features that allow the issuer to repay all or a portion of the security at par before its stated maturity without penalty. In general, as interest rates rise, the estimated fair value of fixed-rate securities will decrease; as interest rates fall, their value will increase. We generally view changes in fair value caused by changes in interest rates as temporary, which is consistent with our experience.
	At December 31, 2013 and 2012, INB, which owned the HTM portfolio, also had the ability and intent to hold all of the investments for a period of time sufficient for the estimated fair value of the securities with unrealized losses to recover, which may be at the time of maturity. Accordingly, we viewed all the gross unrealized losses related to the HTM portfolio as of those dates to be temporary for the reasons noted above.
	Except for corporate securities, the estimated fair values disclosed in this footnote for HTM securities were obtained from a third-party pricing service that used Level 2 inputs. For corporate securities, estimated fair value relied on a complex valuation model that factored in numerous assumptions and data, including anticipated discounts related to illiquid trading markets, credit and interest rate risk, which are Level 3 inputs.
	The following table is a summary of the carrying value (amortized cost) and estimated fair value of HTM securities at December 31, 2013, by remaining period to contractual maturity (ignoring earlier call dates, if any). The amounts reported in the table also did not consider the effects of possible prepayments or unscheduled repayments. Accordingly, actual maturities may differ from contractual maturities shown in the table.
	($ in thousands)		Amortized			Estimated			Wtd-Avg
			Cost			Fair Value			Yield
	Due in one year or less		$	12,329		$	12,394			1.27	%
	Due after one year through five years			262,878			259,611			0.9
	Due after five years through ten years			56,507			54,962			1.38
	Due after ten years			52,223			51,540			1.87
			$	383,937		$	378,507			1.11	%
	Prior to December 13, 2013, INB also owned corporate securities that were also classified as HTM. The investments consisted of mezzanine-class, variable-rate pooled trust preferred securities backed by debt obligations of companies in the banking industry. At the time of purchase in 2006 and 2007, these securities were investment grade rated, but subsequently their credit standing slowly deteriorated due to various factors, all of which severely reduced the demand for these securities, depressed their market values and rendered their trading market inactive. As a result and based on various assumptions and present value analyses of projected cash flows, the securities were deemed to be other than temporarily impaired (OTTI) to varying degrees. A total of $5.2 million of credit losses (or OTTI charges) were recorded on these securities since the end of 2008.
	The table below provides a roll forward of credit losses recognized on the corporate securities for the periods indicated.
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	Balance at beginning of period		$	4,233		$	3,651		$	3,450
	Additional credit losses on debt securities for which OTTI was previously recognized			964			582			201
	Balance at end of period		$	5,197		$	4,233		$	3,651
	In December 2013, INB no longer had the intention or ability to hold the corporate securities to maturity (due to their non-investment grade status as well as a new regulatory rule (the “Volcker Rule” issued by federal regulators in December 2013 pursuant to the Dodd-Frank Act) that likely would have required INB to sell the securities). Consequently, the securities were transferred to available for sale from HTM and subsequently sold in December 2013.
	The table below provides information ($ in thousands) regarding the corporate securities as of the date of sale.
	Original		Cumulative			Cumulative			Net			Net Proceeds		Net Gain
	Cost		Cash Payments			OTTI			Carrying			from Sale		on Sale
	Basis		Applied to Cost			Charges			Value
	$8,029		$	(263	)	$	(5,197	)	$	2,569		$	4,050	$	1,481
	At December 31, 2013 and 2012, the carrying value (estimated fair value) of securities available for sale amounted to approximately $1.0 million. The investment represented approximately 91,700 and 90,000 shares, respectively, of an intermediate bond fund that holds securities that are deemed to be qualified under the Community Reinvestment Act.

Loans_Receivable

Loans Receivable	12 Months Ended
	Dec. 31, 2013
Receivables [Abstract]	'
Loans Receivable	'
	3. Loans Receivable
	Major classifications of loans receivable are summarized as follows:
			At December 31, 2013								At December 31, 2012
	($ in thousands)		# of Loans				Amount				# of Loans				Amount
	Loans Secured By Real Estate:
	Commercial loans			394			$	838,766				376			$	852,213
	Multifamily loans			138				210,270				142				208,699
	One to four family loans			20				72,064				13				41,676
	Land loans			5				9,178				7				7,167
				557				1,130,278				538				1,109,755
	All Other Loans:
	Business loans			19				1,061				18				949
	Consumer loans			12				211				12				359
				31				1,272				30				1,308
	Loans receivable, gross			588				1,131,550				568				1,111,063
	Deferred loan fees							(4,028	)							(3,597	)
	Loans receivable, net of deferred fees							1,127,522								1,107,466
	Allowance for loan losses							(27,833	)							(28,103	)
	Loans receivable, net						$	1,099,689							$	1,079,363
	Loans 90 days past due and still accruing interest - At December 31, 2013, there were three loans totaling $4.1 million, compared to two loans totaling $4.4 million at December 31, 2012. These loans had matured and were in the process of being extended as of those dates. The borrowers were making the required monthly loan payments.
	Loans on nonaccrual status - At December 31, 2013 and 2012, there were $35.9 million and $45.9 million of loans, respectively, on nonaccrual status, which included restructured loans (or “TDRs”) of $33.2 million and $36.3 million, respectively. All the TDRs were current and performing in accordance with their restructured terms but were maintained on nonaccrual status based on regulatory guidance.
	TDRs on accrual status - At December 31, 2013 and 2012, there were $13.5 million and $20.1 million of TDR loans, respectively, classified as accruing TDRs.
	All of our nonaccrual loans and TDR loans were considered impaired loans. At December 31, 2013, we also had one performing and accruing loan of $7.8 million that was classified as impaired.
	The tables below summarize certain information regarding our impaired loans as follows:
	($ in thousands)		Recorded Investment by State (1)																							Specific		Total		# of
																										Valuation		Unpaid		Loans
	At December 31, 2013		NY				FL				VA				GA			CT		OH		SD		Total		Allowance (2)		Principal (3)
	Type
	Retail		$	8,223			$	9,005			$	7,828			$	—		$	2,719	$	1,000	$	—	$	28,775	$	3,052	$	36,216		7
	Office Building			—				14,937				—				8,695			—		—		—		23,632		1,947		23,632		3
	Multifamily			—				3,128				—				—			—		—		—		3,128		594		3,128		2
	Land			—				—				—				—			—		—		1,625		1,625		500		1,625		1
	Totals		$	8,223			$	27,070			$	7,828			$	8,695		$	2,719	$	1,000	$	1,625	$	57,160	$	6,093	$	64,601		13
	($ in thousands)		Recorded Investment by State (1)																			Specific		Total		# of
																						Valuation		Unpaid		Loans
	At December 31, 2012		NY				FL				NJ				OH			SD		Total		Allowance (2)		Principal (3)
	Type
	Retail		$	11,837			$	9,005			$	—			$	1,000		$	—	$	21,842	$	1,966	$	27,596		6
	Office Building			—				17,988				883				—			—		18,871		583		19,621		3
	Warehouse			950				—				—				—			—		950		28		950		1
	Mixed-use commercial			8,632				—				500				—			—		9,132		1,248		9,421		4
	Multifamily			—				12,577				—				—			—		12,577		1,542		14,225		6
	Land			515				—				—				—			2,086		2,601		521		2,601		3
	Totals		$	21,934			$	39,570			$	1,383			$	1,000		$	2,086	$	65,973	$	5,888	$	74,414		23
	-1	Represents unpaid principal less partial principal charge offs and interest received and applied as a reduction of principal in certain cases.
	-2	Represents a specific valuation allowance against the recorded investment, which is included as part of our overall allowance for loan losses.
	All impaired loans at the dates indicated in the table had a specific valuation allowance.
	-3	Represents contractual unpaid principal balance (shown for informational purposes only). The borrowers are obligated to pay such amounts.
	However, the ultimate collection by us of such amounts in this column is not assured.
	Other information related to our impaired loans is summarized as follows:
			For the Year Ended December 31,
	($ in thousands)		2013				2012				2011
	Average recorded investment in nonaccrual loans		$	40,345			$	52,199			$	51,356
	Total cash basis interest income recognized on nonaccrual loans			2,265				2,660				2,437
	Average recorded investment in accruing TDR loans			13,918				12,289				5,417
	Total interest income recognized on accruing TDR loans under modified terms			734				739				299
	Age analysis of our loan portfolio by segment at December 31, 2013 is summarized as follows:
	($ in thousands)		Total				Current				Past Due				Past Due			Past Due		Total		Total
			Portfolio								31-59				60-89			90 or more		Past Due		Classified
											Days				Days			Days				Nonaccrual
	Accruing Loans:
	Commercial real estate		$	802,863			$	796,980			$	1,796			$	—		$	4,087	$	5,883	$	—
	Multifamily			210,270				209,426				844				—			—		844		—
One to four family			72,064				72,064				—				—			—		—		—
Land			9,178				9,178				—				—			—		—		—
All other			1,272				1,271				1				—			—		1		—
Total accruing loans			1,095,647				1,088,919				2,641				—			4,087		6,728		—
Nonaccrual Loans (1):
Commercial real estate			35,903				35,903				—				—			—		—		35,903
Total nonaccrual loans			35,903				35,903				—				—			—		—		35,903
Total loans		$	1,131,550			$	1,124,822			$	2,641			$	—		$	4,087	$	6,728	$	35,903
Age analysis of our loan portfolio by segment at December 31, 2012 is summarized as follows:
($ in thousands)		Total				Current				Past Due				Past Due			Past Due		Total		Total
		Portfolio								31-59				60-89			90 or more		Past Due		Classified
										Days				Days			Days				Nonaccrual
Accruing Loans:
Commercial real estate		$	816,357			$	799,130			$	12,836			$	—		$	4,391	$	17,227	$	—
Multifamily			198,942				198,942				—				—			—		—		—
One to four family			41,676				41,676				—				—			—		—		—
Land			6,882				4,221				2,661				—			—		2,661		—
All other			1,308				1,308				—				—			—		—		—
Total accruing loans			1,065,165				1,045,277				15,497				—			4,391		19,888		—
Nonaccrual Loans (1):
Commercial real estate			35,856				32,701				—				—			3,155		3,155		35,856
Multifamily			9,757				7,261				—				—			2,496		2,496		9,757
Land			285				285				—				—			—		—		285
Total nonaccrual loans			45,898				40,247				—				—			5,651		5,651		45,898
Total loans		$	1,111,063			$	1,085,524			$	15,497			$	—		$	10,042	$	25,539	$	45,898
-1	The amount of nonaccrual loans in the current column included $33.2 million of TDRs at December 31, 2013 and $36.3 million of TDRs at December 31, 2012 for which payments were being made in accordance with their restructured terms, but the loans were maintained on nonaccrual status in accordance with regulatory guidance. The remaining portion at both dates was comprised of certain paying loans classified nonaccrual due to concerns regarding the borrowers’ ability to continue making payments. Interest income from loan payments on all loans in nonaccrual status is recognized on a cash basis, provided the remaining principal balance is deemed collectible.
Information regarding the credit quality of the loan portfolio based on our internally assigned grades follows:
($ in thousands)		Pass				Special Mention				Substandard (1)				Total
At December 31, 2013
Commercial real estate		$	772,900			$	3,522			$	62,344			$	838,766
Multifamily			204,298				2,369				3,603				210,270
One to four family			72,064				—				—				72,064
Land			7,553				—				1,625				9,178
All other			1,272				—				—				1,272
Total loans		$	1,058,087			$	5,891			$	67,572			$	1,131,550
Allocation of allowance for loan losses		$	20,720			$	169			$	6,944			$	27,833
At December 31, 2012
Commercial real estate		$	775,136			$	17,041			$	60,036			$	852,213
Multifamily			193,738				2,384				12,577				208,699
One to four family			41,676				—				—				41,676
Land			4,566				—				2,601				7,167
All other			1,308				—				—				1,308
Total loans		$	1,016,424			$	19,425			$	75,214			$	1,111,063
Allocation of allowance for loan losses		$	20,037			$	443			$	7,623			$	28,103
-1	Substandard loans consisted of $35.9 million of nonaccrual loans, $13.1 million of accruing TDRs and $18.6 million of other performing loans at December 31, 2013, compared to $45.9 million of nonaccrual loans, $20.1 million of accruing TDRs and $9.2 million of other performing loans at December 31, 2012. At December 31, 2013, we also had one accruing TDR for $0.4 million which was rated pass.
The geographic distribution of the loan portfolio by state follows:
($ in thousands)		At December 31, 2013								At December 31, 2012
		Amount				% of Total				Amount				% of Total
New York		$	670,052				59.2	%		$	717,141				64.5	%
Florida			321,812				28.4				286,619				25.8
North Carolina			22,611				2				14,256				1.3
Georgia			18,799				1.7				11,752				1.1
Pennsylvania			16,898				1.5				10,270				0.9
New Jersey			15,650				1.4				26,425				2.4
Kentucky			11,930				1.1				7,512				0.7
Virginia			11,491				1				11,758				1.1
South Carolina			9,223				0.8				5,853				0.5
Connecticut			8,429				0.7				11,216				1
Tennessee			5,843				0.5				770				0.1
Michigan			5,599				0.5				450				0
Ohio			4,703				0.4				2,260				0.2
Indiana			2,820				0.2				1,098				0.1
All other states			5,690				0.5				3,683				0.3
		$	1,131,550				100	%		$	1,111,063				100	%
Information regarding loans restructured during 2013 and 2012 is as follows:
				Number				Recorded Investment
($ in thousands)				of Loans				Pre-Modification				Post-Modification
In 2013		- Commercial real estate - extended maturity date			2			$	9,159			$	9,159
In 2012		- Commercial real estate - extended maturity date			1			$	5,010			$	5,010
		- Multifamily - extended maturity date			1				1,805				1,805
		- Land - extended maturity date			2				520				520
					4			$	7,335			$	7,335
During 2013, there was one TDR in the amount of $3.0 million that defaulted in March 2013 and it was subsequently paid off in June 2013. During 2013, one TDR in the amount of $1.9 million matured. The loan was re-financed by INB and transferred to a performing non-TDR category since the borrower was no longer experiencing financial difficulties. For 2012, there were no TDRs that defaulted or TDRs transferred to a non-TDR loan category.
The distribution of TDRs by accruing versus non-accruing, by loan type and by geographic distribution follows:
($ in thousands)		At December 31, 2013				At December 31, 2012
Performing - nonaccrual status		$	33,184			$	36,291
Performing - accrual status			13,429				20,076
		$	46,613			$	56,367
Commercial real estate		$	41,860			$	43,685
Multifamily			3,128				10,081
Land			1,625				2,601
		$	46,613			$	56,367
New York		$	8,223			$	18,478
Florida			27,070				33,920
New Jersey			—				883
Georgia			8,695				—
Ohio			1,000				1,000
South Dakota			1,625				2,086
		$	46,613			$	56,367

Allowance_for_Loan_Losses

Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Allowance for Loan Losses	'
	4. Allowance for Loan Losses
	Activity in the allowance for loan losses by loan type for the periods indicated follows:
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Balance at December 31, 2010		$	21,919		$	11,234		$	122	$	1,553		$	12		$	34,840
	Loan chargeoffs			(7,186	)		(2,412	)		—		—			—			(9,598	)
	Loan recoveries			90			65			—		—			—			155
	Provision (credit) for loan losses			4,333			(39	)		210		516			(2	)		5,018
	Balance at December 31, 2011		$	19,156		$	8,848		$	332	$	2,069		$	10		$	30,415
	Loan chargeoffs			(2,588	)		(564	)		—		—			—			(3,152	)
	Loan recoveries			507			333			—		—			—			840
	Provision (credit) for loan losses			1,976			(1,736	)		788		(1,026	)		(2	)		—
	Balance at December 31, 2012		$	19,051		$	6,881		$	1,120	$	1,043		$	8		$	28,103
	Loan chargeoffs			(1,932	)		(6	)		—		—			—			(1,938	)
	Loan recoveries			1,053			682			—		483			—			2,218
	Provision (credit) for loan losses			231			(2,460	)		1,897		(218	)		—			(550	)
	Balance at December 31, 2013		$	18,403		$	5,097		$	3,017	$	1,308		$	8		$	27,833
	The following table sets forth the balances of our loans receivable by segment and impairment evaluation and the allowance for loan losses associated with such loans at December 31, 2013.
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Loans:
	Individually evaluated for impairment		$	52,407		$	3,128		$	—	$	1,625		$	—		$	57,160
	Collectively evaluated for impairment			786,359			207,142			72,064		7,553			1,272			1,074,390
	Total loans		$	838,766		$	210,270		$	72,064	$	9,178		$	1,272		$	1,131,550
	Allowance for loan losses:
	Individually evaluated for impairment (1)		$	4,999		$	594		$	—	$	500		$	—		$	6,093
	Collectively evaluated for impairment			13,404			4,503			3,017		808			8			21,740
	Total allowance for loan losses		$	18,403		$	5,097		$	3,017	$	1,308		$	8		$	27,833
	-1	See note 3 to financial statements in this report.
	The following table sets forth the balances of our loans receivable by segment and impairment evaluation and the allowance for loan losses associated with such loans at December 31, 2012.
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Loans:
	Individually evaluated for impairment		$	50,795		$	12,577		$	—	$	2,601		$	—		$	65,973
	Collectively evaluated for impairment			801,418			196,122			41,676		4,566			1,308			1,045,090
	Total loans		$	852,213		$	208,699		$	41,676	$	7,167		$	1,308		$	1,111,063
	Allowance for loan losses:
	Individually evaluated for impairment (1)		$	3,825		$	1,542		$	—	$	521		$	—		$	5,888
	Collectively evaluated for impairment			15,226			5,339			1,120		522			8			22,215
	Total allowance for loan losses		$	19,051		$	6,881		$	1,120	$	1,043		$	8		$	28,103
	-1	See note 3 to financial statements in this report.

Premises_and_Equipment_Lease_C

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income	12 Months Ended
	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income	'
	5. Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income
	Premises and equipment is as follows:
			At December 31,
	($ in thousands)		2013			2012
	Land		$	1,264		$	1,264
	Buildings			5,214			5,020
	Leasehold improvements			1,786			1,632
	Furniture, fixtures and equipment			1,713			1,770
	Total cost			9,977			9,686
	Less accumulated deprecation and amortization			(5,921	)		(5,808	)
	Net book value		$	4,056		$	3,878
	The offices of IBC and INB’s headquarters and full-service banking office are located in leased premises on the entire fourth floor of One Rockefeller Plaza in New York City, with such lease expiring in March 2024. In addition, INB leases its Belcher Road and Mandalay Avenue branch offices in Florida, with such leases expiring in September 2022 and January 2016, respectively. All the leases above contain operating escalation clauses related to taxes and operating costs based upon various criteria and are accounted for as operating leases. INB owns all of its remaining offices in Florida and also leases a portion of the space in its office buildings in Florida that is not used for banking operations to other companies under leases that have expiration dates at various times through August 2017.
	Depreciation and amortization of premises and equipment is reflected as a component of noninterest expense in the consolidated statements of earnings and amounted to $0.4 million in 2013, 2012 and 2011.
	Future minimum annual lease payments and sublease income due under non-cancelable leases at December 31, 2013 are as follows:
			Minimum Rentals
	($ in thousands)		Lease Expense (1)			Sublease Income (2)
	In 2014		$	1,540		$	276
	In 2015			1,569			245
	In 2016			1,506			229
	In 2017			1,504			153
	In 2018			1,507			—
	Thereafter			8,314			—
			$	15,940		$	903
	-1	Rent expense under operating leases aggregated to $1.6 million in 2013, $1.5 million in 2012 and $1.2 million in 2011.
	-2	Rent income aggregated to $0.4 million in 2013, 2012 and 2011.

Foreclosed_Real_Estate_and_Val

Foreclosed Real Estate and Valuation Allowance for Real Estate Losses	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Foreclosed Real Estate and Valuation Allowance for Real Estate Losses	'
	6. Foreclosed Real Estate and Valuation Allowance for Real Estate Losses
	Real estate acquired through foreclosure by property type is summarized as follows:
			At December 31, 2013						At December 31, 2012
	($ in thousands)		# of Properties			Amount (1)			# of Properties		Amount (1)
	Commercial real estate			2		$	3,984			2	$	2,790
	Multifamily			1			6,685			3		12,000
	Land			—			—			1		1,133
	Real estate acquired through foreclosure			3		$	10,669			6	$	15,923
	-1	Reported net of any associated valuation allowance.
	Activity in the valuation allowance for real estate losses is as follows:
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	Valuation allowance at beginning of year		$	5,339		$	6,037		$	2,688
	Provision for real estate losses charged to expense			1,105			4,068			3,349
	Real estate chargeoffs:
	Commercial real estate			(256	)		(2,280	)		—
	Multifamily			(3,157	)		—			—
	Land			(1,014	)		(2,486	)		—
	Total real estate chargeoffs			(4,427	)		(4,766	)		—
	Valuation allowance at end of year		$	2,017		$	5,339		$	6,037

Deposits

Deposits	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Deposits	'
	7. Deposits
	Scheduled maturities of certificates of deposit accounts (CDs) are as follows:
		At December 31, 2013					At December 31, 2012
	($ in thousands)	Amount		Wtd-Avg			Amount		Wtd-Avg
				Stated Rate					Stated Rate
	Within one year	$	307,122		1.97	%	$	519,236		2.92	%
	Over one to two years		167,323		1.92			181,698		2.79
	Over two to three years		170,956		1.92			89,049		2.74
	Over three to four years		106,700		2.5			60,119		3.02
	Over four years		129,678		2.06			86,776		2.93
		$	881,779		2.03	%	$	936,878		2.89	%
	CDs of $100,000 or more totaled $473 million at December 31, 2013 and $463 million at December 31, 2012 and included brokered CDs of $91 million and $78 million, respectively. At December 31, 2013, all CDs of $100,000 or more (inclusive of brokered CDs) by remaining maturity were as follows: $143 million due within one year; $75 million due over one to two years; $107 million due over two to three years; $67 million due over three to four years; and $81 million due thereafter. At December 31, 2013, brokered CDs had a weighted average rate of 3.01% and their remaining maturities were as follows: $23 million due within one year; $5 million due over one to two years; $13 million due over two to three years; $29 million due over three to four years and $21 million due over four years.
	Interest expense on deposit accounts is as follows:
		For the Year Ended December 31,
	($ in thousands)	2013		2012			2011
	Interest checking accounts	$	65	$	65		$	79
	Savings accounts		29		34			58
	Money market accounts		1,530		2,142			3,669
	Certificates of deposit accounts		23,806		33,590			43,776
		$	25,430	$	35,831		$	47,582
	We have deposit accounts from affiliated companies, our directors, our executive officers and members of their immediate families and related business interests of approximately $3.7 million at December 31, 2013 and $3.4 million at December 31, 2012.

FHLB_Advances_and_Lines_of_Cre

FHLB Advances and Lines of Credit	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
FHLB Advances and Lines of Credit	'
	8. FHLB Advances and Lines of Credit
	At December 31, 2013, INB had $24 million of unsecured credit lines that were cancelable by the lender at any time. As a member of the FHLB and the FRB) INB can borrow from these institutions on a secured basis. At December 31, 2013, INB had available collateral consisting of investment securities and certain loans that could be pledged to support additional total borrowings of approximately $403 million from the FHLB and FRB, if needed.
	The following is a summary of certain information regarding INB’s borrowings in the aggregate:
		At or For the Year Ended December 31,
	($ in thousands)	2013			2012			2011
	Balance at year end	$	—		$	—		$	17,500
	Maximum amount outstanding at any month end during the year	$	—		$	13,500		$	25,500
	Average outstanding balance for the year	$	295		$	9,087		$	21,574
	Weighted-average interest rate paid for the year		0.38	%		4.27	%		4.1	%
	Weighted-average interest rate at year end		—			—			4.1	%
	In November 2012, FHLB advances totaling $7.0 million were repaid with cash on hand prior to their stated maturity. A loss of $0.2 million from the early extinguishment of these advances was recorded. This loss represented a prepayment penalty associated with the early retirement of these advances.

Subordinated_Debentures_Capita

Subordinated Debentures - Capital Securities	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Subordinated Debentures - Capital Securities	'
	9. Subordinated Debentures - Capital Securities
	Capital Securities (commonly referred to as trust preferred securities) outstanding are summarized as follows:
			At December 31, 2013							At December 31, 2012
	($ in thousands)		Principal		Accrued		Interest			Principal		Accrued		Interest
					Interest		Rate					Interest		Rate
					Payable							Payable
	Capital Securities II - debentures due September 17, 2033		$	15,464	$	275		3.19	%	$	15,464	$	1,661		3.26	%
	Capital Securities III - debentures due March 17, 2034			15,464		261		3.03	%		15,464		1,577		3.1	%
	Capital Securities IV - debentures due September 20, 2034			15,464		223		2.65	%		15,464		1,370		2.71	%
	Capital Securities V - debentures due December 15, 2036			10,310		109		1.89	%		10,310		1,620		1.96	%
			$	56,702	$	868				$	56,702	$	6,228
	The securities are obligations of IBC’s wholly owned statutory business trusts, Intervest Statutory Trust II, III, IV and V, respectively. Each Trust was formed with a capital contribution from IBC and for the sole purpose of issuing and administering the Capital Securities. The proceeds from the issuance of the Capital Securities together with the capital contribution for each Trust were used to acquire IBC’s Junior Subordinated Debentures (the “Debentures”) that are due concurrently with the Capital Securities. The Capital Securities, net of IBC’s capital contributions of $1.7 million, total $55 million and qualify as regulatory Tier 1 capital up to certain limits. IBC has guaranteed the payment of distributions on, payments on any redemptions of, and any liquidation distribution with respect to the Capital Securities. Issuance costs associated with Capital Securities II, III and IV were capitalized and are being amortized over the contractual life of the securities using the straight-line method. The unamortized balance totaled approximately $0.7 million at December 31, 2013. There were no issuance costs for Capital Securities V.
	Interest payments on the Debentures (and the corresponding distributions on the Capital Securities) are payable in arrears as follows:
		•		Capital Securities II - quarterly at the rate of 2.95% over 3 month libor;
		•		Capital Securities III - quarterly at the rate of 2.79% over 3 month libor;
		•		Capital Securities IV- quarterly at the rate of 2.40% over 3 month libor; and
		•		Capital Securities V - quarterly at the rate of 1.65% over 3 month libor.
	Interest payments may be deferred at any time and from time to time during the term of the Debentures at IBC’s election for up to 20 consecutive quarterly periods, or 5 years, with no limitations on the number of deferral periods IBC may elect, provided, however, no deferral period may extend beyond the maturity date of the Debentures. During an interest deferral period, interest will continue to accrue on the Debentures and interest on such accrued interest will accrue at an annual rate equal to the interest rate in effect for such deferral period, compounded quarterly from the date such interest would have been payable were it not deferred. At the end of the deferral period, IBC will be obligated to pay all interest then accrued and unpaid. During the deferral period, among other restrictions, IBC and any affiliate cannot, subject to certain exceptions: (i) declare or pay any dividends or distributions on, or redeem, purchase or acquire any capital stock of IBC or its affiliates (other than payment of dividends to IBC); or (ii) make any payment of principal or interest or premium on, or repay, repurchase or redeem any debt securities of IBC or its affiliates that rank pari passu with or junior to the Debentures. In February 2010, as required by its primary regulator, IBC exercised its right to defer interest payments as described above. In June 2013, IBC, with approval from its regulator, repaid all accrued interest payments in arrears as of that date on the Debentures. In September 2013, IBC again exercised its right to defer interest payments on the Debentures due to the restrictions of its written agreement with its regulator.
	The Capital Securities are subject to mandatory redemption as follows: (i) in whole, but not in part, upon repayment of the Debentures at stated maturity or earlier, at the option of IBC, within 90 days following the occurrence and continuation of certain changes in the tax or capital treatment of the Capital Securities, or a change in law such that the statutory trust would be considered an investment company, contemporaneously with the redemption by IBC of the Debentures; and (ii) in whole or in part at any time contemporaneously with the optional redemption by IBC of the Debentures in whole or in part. Any redemption would be subject to the receipt of regulatory approvals.

Stockholders_Equity_and_Redemp

Stockholders' Equity and Redemption of Preferred Stock	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Stockholders' Equity and Redemption of Preferred Stock	'
	10. Stockholders’ Equity and Redemption of Preferred Stock
	Prior to May 24, 2012, IBC had two classes of authorized common stock - Class A and Class B. At IBC’s 2012 Annual Meeting of Stockholders held on May 24, 2012, stockholders approved an amendment and restatement of IBC’s Certificate of Incorporation to eliminate any and all references to Class B common stock and to rename its Class A common stock “common stock.”
	IBC is authorized to issue up to 62,300,000 shares of its capital stock, consisting of 62,000,000 shares of common stock and 300,000 shares of preferred stock. IBC’s board of directors determines the powers, preferences and rights, and the qualifications, limitations, and restrictions thereof on any series of preferred stock issued.
	From December 23, 2008 through June 24, 2013 a total of 25,000 shares of preferred stock were designated as Series A (the “Preferred Stock”) and were owned by the U.S. Department of the Treasury (the “Treasury”). The Preferred Stock was issued to the Treasury by IBC in connection with IBC’s participation in the Capital Purchase Program (the “CPP”) under the Treasury’s Troubled Asset Relief Program (“TARP”), together with a ten-year warrant (the “Warrant”) to purchase 691,882 shares of IBC’s common stock at an exercise price of $5.42 per share. In February 2010, IBC ceased the declaration and payment of dividends on the Preferred Stock as required by IBC’s primary regulator.
	On June 6, 2013, the Treasury announced its intent to sell its investment in IBC’s Preferred Stock, along with similar investments the Treasury had made in five other financial institutions, primarily to qualified institutional buyers and certain institutional accredited investors. IBC obtained regulatory approvals allowing it to participate in the auction. Using a modified Dutch auction methodology that established a market price by allowing investors to submit bids at specified increments during the period from June 10 through June 13, 2013, the Treasury auctioned all of IBC’s 25,000 shares of Preferred Stock. IBC was the winning bidder on 6,250 shares of the Preferred Stock and the remaining 18,750 shares were purchased by unrelated third parties. The closing price of the auctioned shares was $970.00 per share.
	On June 24, 2013, IBC completed the repurchase of 6,250 shares of the Preferred Stock from the Treasury and those shares were retired. The shares were repurchased for $6.1 million, plus an additional $1.2 million in accrued and unpaid dividends through June 24, 2013, for a total of $7.3 million.
	On August 15, 2013, IBC redeemed the remaining 18,750 shares of the Preferred Stock held by the unrelated third parties for a purchase price equaling the stated liquidation value of $1,000 per share, plus accumulated and unpaid dividends earned through August 15, 2013. The total cost of redeeming these shares was $22.6 million, which included $3.9 million of accrued and unpaid dividends. IBC received all necessary regulatory approvals to complete the redemption. The Treasury continued to hold the Warrant as of December 31, 2013.

Asset_and_Dividend_Restriction

Asset and Dividend Restrictions	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Asset and Dividend Restrictions	'
	11. Asset and Dividend Restrictions
	INB is required under FRB regulations to maintain reserves against its transaction accounts. At December 31, 2013 and 2012, balances maintained as reserves were approximately $1.0 million. The FRB pays interest on required and excess reserve balances based on a defined formula.
	As a member of the FRB and FHLB, INB must maintain an investment in the capital stock of each entity. At December 31, 2013 and 2012, the total investment aggregated to $8.2 million. At December 31, 2013 and 2012, U.S. government agency security investments with a carrying value of approximately $27 million and $17 million, respectively, were pledged against lines of credit. At December 31, 2013 and 2012, certain mortgage loans totaling approximately $71 million and $105 million, respectively, were also pledged against lines of credit.
	The payment of cash dividends by IBC to its common and preferred shareholders and the payment of cash dividends by INB to IBC are subject to various regulatory restrictions, as well as restrictions that may arise from any outstanding indentures and other capital securities. These restrictions take into consideration various factors such as whether there are sufficient net earnings, as defined, liquidity, asset quality, capital adequacy and economic conditions. Since February 2010, as required by the FRB, IBC’s primary regulator, IBC may not, without the prior approval of the FRB, pay dividends on or redeem its capital stock, pay interest on or redeem its trust preferred securities, or incur new debt. No cash common dividends were declared or paid in 2013, 2012 or 2011. See note 10 for a discussion of cash preferred dividends paid in 2013.

Profit_Sharing_Plans

Profit Sharing Plans	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Profit Sharing Plans	'
	12. Profit Sharing Plans
	We have a tax-qualified profit sharing plan for our employees in accordance with the provisions of Section 401(k) of the Internal Revenue Code, whereby our eligible employees meeting certain length-of-service requirements may make tax-deferred contributions up to certain limits. We made discretionary matching contributions of up to 4% of employee compensation, which vest to the employees over a five-year period. Total cash contributions to the plan aggregated to $164,000, $161,000 and $141,000 in 2013, 2012 and 2011, respectively, and were included in the line item “salaries and employee benefits” in the consolidated statements of earnings.

Common_Stock_Warrant_Options_a

Common Stock Warrant, Options and Restricted Common Stock	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Common Stock Warrant, Options and Restricted Common Stock	'
	13. Common Stock Warrant, Options and Restricted Common Stock
	IBC has shareholder-approved incentive plans, the 2006 Long Term Incentive Plan and the 2013 Equity Incentive Plan (together referred to as the “Plans”) under which stock options, restricted stock and other forms of incentive compensation may be awarded from time to time to officers, employees and directors of IBC and its subsidiaries. The maximum number of shares of common stock that may be awarded under the Plans is 2,250,000. At December 31, 2013, 789,003 shares of common stock were available for award under the Plans.
	A summary of selected information regarding option awards made under the Plans for the three-year period ended December 31, 2013 follows. There were no option awards made in 2013 or 2012:
	($ in thousands, except per option amounts)		2011
			Option Award
	Date of award			12/8/11
	Total options awarded			44,100
	Exercise price of option		$	2.55
	Estimated fair value per option (1)		$	1.67
	Total estimated fair value of award		$	73,647
	Assumptions used in Black-Scholes Model:
	Expected dividend yield (2)			0	%
	Expected stock volatility (3)			75	%
	Risk-free interest rate (4)			1.13	%
	Expected term in years (5)			6
	-1	Fair value was estimated at the grant date of the award based on the Black-Scholes option-pricing model using the assumptions noted in the table above. The assumptions are subjective in nature, involve uncertainties and therefore, cannot be determined with precision. The Black-Scholes option pricing model also contains certain inherent limitations when applied to options which are not immediately exercisable and are not traded on public markets.
	-2	No dividends were assumed to be declared and paid for shares underlying the option grants.
	-3	Expected stock volatility is estimated based on an assessment of historical volatility of IBC’s common stock.
	-4	Risk-free interest rate was derived from a U.S. Treasury security having a similar expected life as the option as of the grant date.
	-5	Expected term (average life) was calculated using the “simplified method” as prescribed by the SEC guidance.
	A summary of the activity in IBC’s outstanding common stock warrant and options and related information follows:
	($ in thousands, except per share amounts)		Exercise Price Per Warrant/Option																					Wtd-Avg.
																								Exercise
			$5.42 (1)			$17.10			$7.50			$4.02			$3.00			$2.55			Total			Price
	Outstanding at December 31, 2010			691,882			118,140			122,290			71,710			41,400			—			1,045,422		$	6.79
	Forfeited/expired (2)			—			(300	)		(900	)		(1,200	)		(1,500	)		—			(3,900	)	$	5.44
	Options granted			—			—			—			—			—			44,100			44,100		$	2.55
	Outstanding at December 31, 2011			691,882			117,840			121,390			70,510			39,900			44,100			1,085,622		$	6.62
	Forfeited/expired (2)			—			(1,200	)		(1,200	)		(1,600	)		(1,600	)		(1,800	)		(7,400	)	$	6.13
	Exercised			—			—			—			—			(100	)		—			(100	)	$	3
	Outstanding at December 31, 2012			691,882			116,640			120,190			68,910			38,200			42,300			1,078,122		$	6.63
	Forfeited/expired (2)			—			(6,000	)		(6,200	)		(1,610	)		(2,100	)		(3,500	)		(19,410	)	$	8.8
	Options exercised			—			—			—			(9,900	)		(3,700	)		(3,667	)		(17,267	)	$	3.49
	Outstanding at December 31, 2013			691,882			110,640			113,990			57,400			32,400			35,133			1,041,445		$	6.64
	Expiration date			12/23/18			12/13/17			12/11/18			12/10/19			12/9/20			12/8/21
	Vested and exercisable (3)			100	%		100	%		100	%		100	%		100	%		67	%		99	%
	Wtd-avg contractual remaining term (in years)			5			4			4.9			5.9			6.9			7.9			5.1
	Intrinsic value at December 31, 2013 (4)		$	1,446			—		$	1		$	201		$	146		$	174		$	1,968
	-1	This warrant is held by the U.S. Treasury as described in note 10 to the financial statements.
	-2	Represent options forfeited or expired unexercised.
	-3	The $2.55 options further vest and become 100% exercisable on December 8, 2014. Full vesting may occur earlier upon the occurrence of certain events as defined in the option agreement.
	-4	Intrinsic value was calculated using the closing price of the common stock on December 31, 2013 of $7.51.
	A summary of selected information regarding restricted common stock awards made under the Plans for the three-year period ended December 31, 2013 follows:
	($ in thousands, except per share amounts)		Stock Grant			Stock			Stock
						Grant			Grant
	Grant date of award			12/12/13			1/24/13			1/19/12
	Total restricted shares of stock awarded (1)			135,500			330,700			465,400
	Estimated fair value per share awarded (2)		$	7.21		$	4.5		$	2.9
	Total estimated fair value of award		$	977		$	1,488		$	1,350
	Awards scheduled to vest as follows:
	Jan-13			—			—			256,800
	Jan-14			75,417			49,566			133,455
	Jan-15			44,917			170,888			75,145
	Jan-16			15,166			110,246			—
				135,500			330,700			465,400
	-1	The December 2013 awards were made to five executive officers vesting in five installments over a three-year period. These awards replaced certain awards that were forfeited during 2013 in connection with the requirements of TARP.
	The January 2013 awards were made as follows: a total of 182,000 shares to five executive officers (vesting in two installments, with two thirds vesting on the second anniversary of the grant and the remaining one third on the third anniversary of the grant); a total of 80,000 shares to eight non-employee directors and 68,700 shares to other officers and employees (vesting in three equal installments, with one third vesting on each of the first three anniversary dates of the grant).
	The January 2012 awards were made as follows: a total of 175,000 shares to five executive officers (vesting in two installments, with two thirds vesting on the second anniversary of the grant and the remaining one third on the third anniversary of the grant); a total of 240,000 shares to six non-employee directors (vesting 100% on the first anniversary of the grant); and a total of 50,400 shares to other officers and employees (vesting in three equal installments, with one third on each of the first three anniversary dates of the grant).
	-2	Fair value of each award was estimated as of the grant date based on the closing market price of the common stock on the grant date.
	A summary of activity in outstanding restricted common stock and related information follows:
			Price Per Share
			$2.35			$2.90			$4.50			$7.21			Total
	Outstanding at December 31, 2010			319,300			—			—			—			319,300
Shares forfeited			(1,200	)		—			—			—			(1,200	)
Outstanding at December 31, 2011			318,100			—			—			—			318,100
Shares granted			—			465,400			—			—			465,400
Shares forfeited			(600	)		(600	)		—			—			(1,200	)
Outstanding at December 31, 2012			317,500			464,800			—			—			782,300
Shares vested and no longer restricted			(264,150	)		(256,600	)		—			—			(520,750	)
Shares granted			—			—			330,700			135,500			466,200
Shares forfeited			(53,350	)		(49,883	)		(51,200	)		—			(154,433	)
Outstanding at December 31, 2013 (1) (2)			—			158,317			279,500			135,500			573,317
-1	All outstanding shares of restricted common stock at December 31, 2013 were unvested and subject to forfeiture.
Shares issued at $2.90 will vest as follows: 101,034 on January 19, 2014 and 57,283 on January 19, 2015.
Shares issued at $4.50 will vest as follows: 47,667 on January 24, 2014, 138,667 on January 24, 2015 and 93,166 on January 24, 2016.
Shares issued at $7.21 will vest as follows: 46,250 on January 2, 2014; 29,167 on January 19, 2014; 14,584 on January 19, 2015; 30,333 on January 24, 2015; and 15,166 on January 24, 2016.
-2	Vesting is subject to the grantee’s continued employment with us or, in the case of non-employee directors, the grantee’s continued service as our director on the vesting dates. All of the awards are subject to accelerated vesting upon the death or disability of the grantee or upon a change in control of IBC, as defined in the restricted stock agreements. The record holder of IBC’s restricted shares of common stock possesses all the rights of a holder of our common stock, including the right to receive dividends on and to vote the restricted shares. The restricted shares may not be sold, transferred, pledged, assigned, encumbered, or otherwise alienated or hypothecated until they become fully vested and transferable in accordance with the agreements.
Stock-based compensation expense is recognized on a straight-line basis over the vesting period of the awards and totaled $0.8 million, $1.2 million and $0.3 million in 2013, 2012 and 2011, respectively. As required by GAAP, stock-based compensation expense is recorded as an expense and a corresponding increase to our stockholders’ equity as additional paid-in capital. At December 31, 2013, pre-tax compensation expense related to all nonvested awards of options and restricted stock not yet recognized totaled $1.9 million and such amount is expected to be recognized in the future over a weighted-average period of approximately 1.9 years.
Our income taxes payable for 2013 was reduced by the excess income tax benefit associated with the vesting of restricted common stock awards and the exercise of stock option awards (calculated as the difference between the fair market value of the stock at the vesting date versus the grant date in the case of stock awards and the difference between the fair market value of the stock at the exercise date versus the exercise price per share in the case of options, multiplied by our effective income tax rate). The net tax benefit amounted to $0.6 million and is required to be recorded as an increase to our paid-in capital. There was no such tax benefit for 2012 and 2011.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	14. Income Taxes
	We file a consolidated federal income tax return and combined state and city income tax returns in New York. INB files a state income tax return in Florida. All returns are filed on a calendar year basis. Our income tax returns that have been filed and are no longer subject to examination by taxing authorities are for years prior to 2010. Our Federal returns for 2008, 2009 and 2010 were audited by the Internal Revenue Service. This audit was completed in 2013 and no adjustments were proposed. As of December 31, 2013, our New York State returns for 2010, 2011 and 2012 were being audited and we are not aware of any proposed adjustments as of the date of filing of this report.
	Allocation of our federal, state and local income tax expense between current and deferred portions is as follows:
	($ in thousands)	Current			Deferred			Total
	Year Ended December 31, 2013:
	Federal	$	420		$	9,130		$	9,550
	State and Local		339			1,766			2,105
		$	759		$	10,896		$	11,655
	Year Ended December 31, 2012:
	Federal	$	370		$	7,751		$	8,121
	State and Local		335			1,851			2,186
		$	705		$	9,602		$	10,307
	Year Ended December 31, 2011:
	Federal	$	958		$	6,670		$	7,628
	State and Local		311			1,573			1,884
		$	1,269		$	8,243		$	9,512
	The components of the deferred tax expense are as follows:
		For the Year Ended December 31,
	($ in thousands)	2013			2012			2011
	NOL and AMT credit carryforwards	$	7,353		$	8,084		$	8,138
	Allowances for loan losses and real estate losses		1,597			1,315			484
	Capitalized real estate expenses and nonaccrual interest		36			1,011			(232	)
	Impairment writedowns on investment securities		1,857			(282	)		(86	)
	Deferred compensation and benefits		285			(355	)		(48	)
	Depreciation		(234	)		(166	)		(16	)
	Deferred income		2			(5	)		3
		$	10,896		$	9,602		$	8,243
	The tax effects of the temporary differences that give rise to the deferred tax asset are as follows:
		At December 31,
	($ in thousands)	2013			2012
	NOL and AMT credit carryforwards	$	3,061		$	10,414
	Allowances for loan losses and real estate losses		12,814			14,411
	Capitalized real estate expenses and nonaccrual interest		1,152			1,188
	Impairment writedowns on investment securities		—			1,857
	Unrealized losses on securities available for sale		24			—
	Deferred compensation and benefits		852			1,137
	Depreciation		454			220
	Deferred income		5			7
	Total deferred tax asset	$	18,362		$	29,234
	Our deferred tax asset in the table above arises from to the unrealized benefit for net temporary differences between the financial statement carrying amounts of our existing assets and liabilities and their respective tax bases that will result in future income tax deductions as well as any unused net operating loss carryforwards (NOLs) and Federal AMT credit carry forwards, all of which can be applied against and reduce our future taxable income and tax liabilities. At December 31, 2013, our remaining unused state and local NOLs amounted to approximately $30 million, which are available for state and local income tax purposes. The NOLs expire in 2030.
	We have determined that a valuation allowance for our deferred tax asset was not required at any time during the reporting periods in this report because we believe that it is more likely than not that the asset will be fully realized. This conclusion is based on our taxable earnings history and our future projections of taxable income which indicate that we will be able to generate an adequate amount of future taxable income over a reasonable period of time to fully utilize the deferred tax asset.
	The reconciliation between the statutory federal income tax rate and our effective income tax rate is as follows:
		For the Year Ended December 31,
		2013			2012			2011
	Federal statutory income tax rate		35	%		35	%		35	%
	Increase resulting from:
	State and local income tax rate, net of federal benefit		7.8			9.4			9.3
	All other		1.8			1.4			1.5
	Effective Income Tax Rate		44.6	%		45.8	%		45.8	%
	As a Delaware corporation not earning income in Delaware, IBC is exempt from Delaware corporate income tax but is required to file an annual report with and pay an annual franchise tax to the State of Delaware. The tax is imposed as a percentage of the capital base of IBC and is reported in the line item “All other” in the noninterest expense section of our statements of earnings. Total annual franchise tax expense was $0.2 million in 2013, 2012 and 2011.

Earnings_Per_Common_Share

Earnings Per Common Share	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Earnings Per Common Share	'
	15. Earnings Per Common Share
	Net earnings available to common stockholders and the weighted-average number of shares used for basic and diluted earnings per common share computations are summarized in the table that follows:
			For the Year Ended December 31,
			2013		2012		2011
	Basic Earnings Per Common Share:
	Net earnings available to common stockholders		$	13,437,000	$	10,421,000	$	9,516,000
	Weighted-Average number of common shares outstanding			21,894,030		21,566,009		21,126,187
	Basic Earnings Per Common Share		$	0.61	$	0.48	$	0.45
	Diluted Earnings Per Common Share:
	Net earnings available to common stockholders		$	13,437,000	$	10,421,000	$	9,516,000
	Weighted-Average number of common shares outstanding:
	Common shares outstanding			21,894,030		21,566,009		21,126,187
	Potential dilutive shares resulting from exercise of warrants /options (1)			99,596		2,187		—
	Total average number of common shares outstanding used for dilution			21,993,626		21,568,196		21,126,187
	Diluted Earnings Per Common Share		$	0.61	$	0.48	$	0.45
	-1	All outstanding options/warrants to purchase shares of our common stock were considered for the Diluted EPS computations and only those that were dilutive (as determined by using the treasury stock method prescribed by GAAP) were included in the diluted earnings per share computations above. In 2013, 2012 and 2011, 224,630, 997,622 and 1,085,622 of options/warrants to purchase common stock, respectively, were not dilutive because the exercise price per share of each option/warrant was above the average market price of our common stock during these periods.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Contingencies	'
	16. Contingencies
	We are periodically a party to or otherwise involved in legal proceedings arising in the normal course of business, such as foreclosure proceedings. Based on review and consultation with our legal counsel, we do not believe that there is any pending or threatened proceeding against us, which, if determined adversely, would have a material effect on our business, results of operations, financial position or liquidity.
	In the first and second quarters of 2013, INB entered into settlement agreements with respect to certain litigation INB had pursued in connection with foreclosure actions it had commenced in 2010 on several of its loans. INB commenced the actions to collect, in one case, insurance proceeds, which it contended had been improperly paid to various third parties, and in another case, damages due to alleged legal malpractice when the loan was originated. As a result of these settlements, INB received net proceeds totaling $2.7 million and $0.1 million in the first and second quarters of 2013, respectively, which were recorded as $1.2 million of recoveries of prior loan charge offs and $1.6 million of recoveries of prior real estate expenses associated with two loans and underlying collateral property.

Contractual_Death_Benefit_Paym

Contractual Death Benefit Payments	12 Months Ended
	Dec. 31, 2013
Postemployment Benefits [Abstract]	'
Contractual Death Benefit Payments	'
	17. Contractual Death Benefit Payments
	We are contractually obligated to pay through June 30, 2014 death benefits to the spouse of our former chairman, Jerome Dansker, pursuant to the terms of his employment agreements with IBC and its former subsidiary, IMC. At December 31, 2013, the remaining amount of death benefit payments payable totaled $0.2 million. In the event of the death of the former chairman’s spouse prior to June 30, 2014, any remaining unpaid payments will be paid by us in a lump sum to the spouse’s estate. We also have a ten-year employment and supplemental benefits agreement with our current Chairman, Mr. Lowell Dansker, which expires on June 30, 2014. Pursuant to the agreement, his annual base salary as of July 1, 2013, is $1.2 million and is subject to annual increases effective July 1st of each year of the term of the agreement based on various criteria. Mr. Dansker’s employment agreement also contains certain other provisions, including disability and death benefits and indemnification. In the event of Mr. Dansker’s disability, as defined in the agreement, or death, we would be obligated to pay to Mr. Dansker’s wife or his estate, as applicable, a specified amount over a period equal to the greater of (i) three years, and (ii) the number of months remaining in the stated term of the agreement. The specified amount is equal to a percentage, 50% in the case of disability and 25% in the case of death, of Mr. Dansker’s monthly base salary had the agreement continued in force and effect. No provision for this contingent liability has been made in the financial statements.

OffBalance_Sheet_Financial_Ins

Off-Balance Sheet Financial Instruments	12 Months Ended
	Dec. 31, 2013
Investments All Other Investments [Abstract]	'
Off-Balance Sheet Financial Instruments	'
	18. Off-Balance Sheet Financial Instruments
	INB is party to financial instruments with off-balance sheet risk in the normal course of its business to meet the financing needs of its customers. These instruments can be in the form of commitments to extend credit, unused lines of credit and standby letters of credit, and may involve, to varying degrees, elements of credit and interest rate risk in excess of the amounts recognized in our financial statements. Our maximum exposure to credit risk is represented by the contractual amount of those instruments. Commitments to extend credit are agreements to lend funds to a customer as long as there is no violation of any condition established in the contract. Such commitments generally have fixed expiration dates or other termination clauses and normally require payment of fees to INB. Since some of the commitments are expected to expire without being drawn upon, the total commitment amount does not necessarily represent future cash requirements. We evaluate each customer’s creditworthiness on a case-by-case basis. Standby letters of credit are conditional commitments issued by INB to guarantee the performance of its customer to a third party. The credit risk involved in the underwriting of letters of credit is essentially the same as that involved in originating loans. INB had no standby letters of credit outstanding at December 31, 2013 or 2012.
	The contractual amounts of off-balance sheet financial instruments are as follows:
		At December 31,
	($ in thousands)	2013		2012
	Commitments to extend credit	$	19,386	$	19,154
	Unused lines of credit		877		854
		$	20,263	$	20,008

Regulatory_Capital_and_Regulat

Regulatory Capital and Regulatory Matters	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Regulatory Capital and Regulatory Matters	'
	19. Regulatory Capital and Regulatory Matters
	General. IBC is subject to regulation, examination and supervision by the FRB. INB is subject to regulation, examination and supervision by the Federal Deposit Insurance Corporation (“FDIC”) and the Office of the Comptroller of the Currency (“OCC”). Both IBC and INB are subject to various minimum regulatory capital requirements. Failure to comply with these requirements can initiate mandatory and discretionary actions by the aforementioned regulators that, if undertaken, could have a material adverse effect on our financial condition, results of operations and business. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, we must meet specific capital guidelines that involve quantitative measures of our assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. These capital amounts are also subject to qualitative judgement by the regulators about components, risk weighting and other factors. Quantitative measures established by the regulations to ensure capital adequacy require us to maintain minimum amounts and ratios of total Tier 1 capital to risk-weighted assets, total Tier 1 capital to average assets and total regulatory capital to risk weighted assets, as defined by the regulations.
	Capital Ratios. We believe that both IBC and INB met all capital adequacy requirements to which they were subject. As of the date of filing of this report, we are not aware of any conditions or events that would have changed the status of such compliance with regulatory capital requirements from December 31, 2013.
	Information regarding our regulatory capital and related ratios is summarized as follows:
			INB						IBC Consolidated
			At December 31,						At December 31,
	($ in thousands)		2013			2012			2013			2012
	Tier 1 capital (1)		$	240,918		$	244,081		$	245,191		$	249,465
	Tier 2 capital			15,479			15,566			15,517			15,620
	Total risk-based capital (2)		$	256,397		$	259,647		$	260,708		$	265,085
	Net risk-weighted assets for regulatory purposes		$	1,225,936		$	1,232,670		$	1,228,994		$	1,238,024
	Average assets for regulatory purposes		$	1,581,713		$	1,690,329		$	1,586,416		$	1,696,410
	Total capital to risk-weighted assets			20.91	%		21.06	%		21.21	%		21.41	%
	Tier 1 capital to risk-weighted assets			19.65	%		19.8	%		19.95	%		20.15	%
	Tier 1 capital to average assets			15.23	%		14.44	%		15.46	%		14.71	%
	-1	IBC’s consolidated Tier 1 capital at both dates included $55 million of IBC’s outstanding qualifying trust preferred securities.
	The table that follows presents information regarding our actual capital and minimum capital requirements.
			Actual Capital						Minimum						Minimum					Minimum
									Under Prompt						To Be “Well Capitalized”					Under Agreement
									Corrective						Under Prompt Corrective					With OCC
									Action Provisions						Action Provisions
	($ in thousands)		Amount			Ratio			Amount			Ratio			Amount		Ratio			Amount		Ratio
	IBC Consolidated at December 31, 2013:
	Total capital to risk-weighted assets (1)		$	260,708			21.21	%	$	98,320			8	%		NA		NA			NA		NA
	Tier 1 capital to risk-weighted assets (1)		$	245,191			19.95	%	$	49,160			4	%		NA		NA			NA		NA
	Tier 1 capital to average assets (1)		$	245,191			15.46	%	$	63,457			4	%		NA		NA			NA		NA
	IBC Consolidated at December 31, 2012:
	Total capital to risk-weighted assets		$	265,085			21.41	%	$	99,042			8	%		NA		NA			NA		NA
	Tier 1 capital to risk-weighted assets		$	249,465			20.15	%	$	49,521			4	%		NA		NA			NA		NA
	Tier 1 capital to average assets		$	249,465			14.71	%	$	67,856			4	%		NA		NA			NA		NA
	INB at December 31, 2013:
	Total capital to risk-weighted assets		$	256,397			20.91	%	$	98,075			8	%	$	122,594		10	%		NA		NA
	Tier 1 capital to risk-weighted assets		$	240,918			19.65	%	$	49,037			4	%	$	73,556		6	%		NA		NA
	Tier 1 capital to average assets		$	240,918			15.23	%	$	63,269			4	%	$	79,086		5	%		NA		NA
	INB at December 31, 2012:
	Total capital to risk-weighted assets		$	259,647			21.06	%	$	98,614			8	%	$	123,267		10	%	$	147,920		12	%
	Tier 1 capital to risk-weighted assets		$	244,081			19.8	%	$	49,307			4	%	$	73,960		6	%	$	123,267		10	%
	Tier 1 capital to average assets		$	244,081			14.44	%	$	67,613			4	%	$	84,516		5	%	$	152,130		9	%
	-1	Assuming IBC had excluded all of its eligible outstanding trust preferred securities (which totaled $55 million) from its Tier 1 capital and included the entire amount in its Tier 2 capital, consolidated proforma capital ratios at December 31, 2013 would have been 21.21%, 15.48% and 11.99%, respectively.
	The table that follows presents additional information regarding our capital adequacy at December 31, 2013.
			INB Regulatory Capital									Consolidated Regulatory Capital
	($ in thousands)		Actual			Required (1)			Excess			Actual			Required		Excess
	Total capital to risk-weighted assets		$	256,397		$	122,594		$	133,803		$	260,708		$	98,320	$	162,388
	Tier 1 capital to risk-weighted assets		$	240,918		$	73,556		$	167,362		$	245,191		$	49,160	$	196,031
	Tier 1 capital to average assets		$	240,918		$	79,086		$	161,832		$	245,191		$	63,457	$	181,734
	-1	Minimum amount required to be considered “Well-Capitalized.”
	Formal Agreements and Regulatory Restrictions. Since January 2011, IBC has been operating under a written agreement with its primary regulator, the Federal Reserve Bank of New York (the “FRB”). The FRB agreement, among other things, requires IBC to use its financial and managerial resources to serve as a source of strength to INB. In addition, the FRB agreement requires IBC to obtain approval from the FRB to do any of the following: declare or pay dividends on its capital stock; take any payments from INB that represent a reduction in INB’s capital; make any distributions of interest, principal or other sums on IBC’s outstanding debt (subordinated debentures); and incur, increase or guarantee any debt or purchase or redeem any shares of IBC’s capital stock. IBC must also notify the FRB when appointing any new director or senior executive officer or changing responsibilities of any senior executive officer. IBC is also restricted in making certain severance and indemnification payments.
	IBC believes that it has complied with all of the requirements of the above agreement. As of December 31, 2013, IBC remained subject to this written agreement with the FRB and all the restrictions contained therein, including those described above. The FRB has advised IBC that it is reviewing the need for such agreement.
	From December 2010 through March 20, 2013, INB was also operating under a formal written agreement with its primary regulator, the Office of the Comptroller of the Currency (the “OCC”). INB’s agreement with the OCC required INB to take certain actions, including (1) creating a compliance committee to monitor and coordinate INB’s performance under the agreement and to submit periodic progress reports to the OCC, (2) develop strategic and capital plans covering at least three years, (3) complete an assessment of management and ensure effective management, and (4) develop programs related to: (i) loan portfolio management; (ii) criticized assets; (iii) loan review; (iv) credit concentrations; (v) accounting for other real estate owned; (vi) maintaining an adequate allowance for loan losses; (vii) liquidity risk management; and (viii) interest rate risk management. On March 21, 2013, INB received notification from the OCC that all of the actions taken by INB since December 2010 satisfied the OCC’s regulatory directives and the OCC terminated the agreement. Additionally, effective March 21, 2013, the OCC terminated its heightened regulatory capital requirements that had also been imposed on INB since February 2010. As a result, as of December 31, 2013, INB was no longer subject to any regulatory agreement or heightened capital requirements.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	20. Fair Value Measurements
	We use fair value measurements to record fair value adjustments to certain of our assets and to determine our fair value disclosures contained in this report.
	At December 31, 2013 and 2012, we had no liabilities recorded at fair value and approximately $1.0 million of assets (comprised of securities available for sale) recorded at fair value on a recurring basis. From time to time, we are required to record at fair value other assets on a non-recurring basis, such as impaired loans and securities and real estate we own through foreclosure. These fair value adjustments generally involve the application of lower-of-cost-or-market accounting or writedowns of individual assets. All of our assets measured at fair value on a nonrecurring basis in this report used Level 3 inputs in the fair value measurements.
	In accordance with GAAP, we group the fair value measurements of our assets and liabilities into 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 – Fair value is based upon quoted prices for identical instruments traded in active markets. This level has the highest level of reliability;
	Level 2 – Fair value is based upon quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant assumptions are observable in the market; and
	Level 3 – Fair Value is generated from model-based techniques that use significant assumptions that generally are not observable in the marketplace. The assumptions used therein reflect our estimates of the assumptions that market participants would use in pricing the asset or liability, and cannot be assured that they would be identical. Valuation techniques for Level 3 include the use of discounted cash flow models.
	The fair value results obtained through the use of Level 3 valuation techniques cannot be determined with precision. Moreover, any of the fair value estimates disclosed in this report may not be realized in an actual sale or immediate settlement of the asset or liability.
	The following tables provide information regarding our assets measured at fair value on a nonrecurring basis.
			Outstanding Carrying Value
			At December 31,
			2013			2012
	($ in thousands)		Level 3			Level 3
	Impaired loans (1) :
	Commercial real estate		$	52,407		$	50,795
	Multifamily			3,128			12,577
	Land			1,625			2,601
	Total impaired loans			57,160			65,973
	Impaired securities (2)			—			3,721
	Foreclosed real estate			10,669			15,923
			Accumulated Losses on
			Outstanding Balance						Total Losses (Gains) (3)
			At December 31,						For the Year Ended December 31,
	($ in thousands)		2013			2012			2013			2012			2011
	Impaired loans:
	Commercial real estate		$	10,294		$	9,979		$	2,053		$	1,038		$	4,936
	Multifamily			598			3,092			(966	)		(364	)		4,190
	Land			500			521			(21	)		(488	)		1,009
	Total impaired loans			11,392			13,592			1,066			186			10,135
	Impaired securities			—			4,233			(517	)		582			201
	Foreclosed real estate			2,017			5,339			142			4,161			3,161
	-1	Outstanding carrying value excludes a specific valuation allowance included in the overall allowance for loan losses. See notes 3 and 4 to the financial statements.
	-2	Comprised at December 31, 2012 of certain held-to maturity investments in trust preferred securities considered other than temporarily impaired. See note 2 to the financial statements.
	-3	Represents total losses or (gains) recognized on all assets measured at fair value on a nonrecurring basis during the period indicated. The losses or (gains) for impaired loans represent the change (before net chargeoffs) during the period in the corresponding specific valuation allowance, while the losses (gains) for foreclosed real estate represent writedowns in carrying values subsequent to foreclosure (recorded as provisions for real estate losses) adjusted for any recoveries of prior write downs and (gains) or losses from the transfer/sale of properties during the period. The (gains) losses on securities represent the total of other than temporary impairment charges and net gains from sales, which are recorded as components of noninterest income. See note 2 to the financial statements in this report.
	The following table presents information regarding the change in assets measured at fair value on a nonrecurring basis for the three-year period ended December 31, 2013.
			Impaired			Impaired			Foreclosed
	($ in thousands)		Securities			Loans			Real Estate
	Balance at December 31, 2010		$	4,580		$	56,555		$	27,064
	Net new impaired loans			—			41,768			—
	Principal repayments/sales			—			(18,198	)		—
	Chargeoffs			—			(9,481	)		—
	Ttransferred to foreclosed real estate			—			(4,375	)		4,375
	Other than temporary impairment writedowns			(201	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(3,349	)
	Gain on sales/transfers from loans			—			—			188
	All other			(1	)		—			—
	Balance at December 31, 2011		$	4,378		$	66,269		$	28,278
	Net new impaired loans			—			19,875			—
	Principal repayments/sales			(75	)		(12,330	)		(12,883	)
	Chargeoffs			—			(3,152	)		—
	Ttransferred to foreclosed real estate			—			(4,689	)		4,689
	Other than temporary impairment writedowns			(582	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(4,068	)
	Loss on sales			—			—			(93	)
	Balance at December 31, 2012		$	3,721		$	65,973		$	15,923
	Net new impaired loans			—			16,122			—
	Principal repayments/sales			(4,238	)		(19,957	)		(8,152	)
	Chargeoffs			—			(1,938	)		—
	Ttransferred to foreclosed real estate			—			(3,040	)		3,040
	Other than temporary impairment writedowns			(964	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(1,105	)
	Gain on sales			1,481			—			963
	Balance at December 31, 2013		$	—		$	57,160		$	10,669
We are required to disclose the estimated fair value of each class of our financial instruments for which it is practicable to estimate, which values are shown in the table that follows on the next page. The fair value of a financial instrument is the current estimated amount that would be exchanged between willing parties, other than in a forced liquidation. The fair value estimates are made at a specific point in time based on available information. A significant portion of our financial instruments, such as our mortgage loans, do not have an active marketplace in which they can be readily sold or purchased to determine fair value. Consequently, fair value estimates for such instruments are based on assumptions made by us that include the instrument’s credit risk characteristics and future estimated cash flows and prevailing interest rates. As a result, these fair value estimates are subjective in nature, involve uncertainties and matters of significant judgment and therefore, cannot be determined with precision. Accordingly, changes in any of our assumptions could cause the fair value estimates to deviate substantially. Fair value estimates included in the table are based on existing on- and off-balance-sheet financial instruments without attempting to estimate the value of anticipated future business and the fair value of assets that are not required to be recorded or disclosed at fair value, like our premises and equipment. Accordingly, the aggregate fair value amounts presented in the table that follows may not necessarily represent the underlying fair value of our Company. In addition, the tax ramifications related to the realization of the unrealized gains and losses can have a significant effect on fair value estimates and have not been considered in the estimates presented in the table.
The carrying and estimated fair values of our financial instruments are as follows:
		At December 31, 2013						At December 31, 2012
($ in thousands)		Carrying			Fair			Carrying			Fair
		Value			Value			Value			Value
Financial Assets:
Cash and cash equivalents (1)		$	24,700		$	24,700		$	60,395		$	60,395
Time deposits with banks (1)			5,370			5,370			5,170			5,170
Securities available for sale, net (1)			965			965			1,000			1,000
Securities held to maturity, net (2)			383,937			378,507			443,777			442,166
FRB and FHLB stock (3)			8,244			8,244			8,151			8,151
Loans receivable, net (3)			1,099,689			1,100,858			1,079,363			1,102,333
Accrued interest receivable (3)			4,861			4,861			5,191			5,191
Loan fees receivable (3)			2,298			1,808			3,108			2,547
Total Financial Assets		$	1,530,064		$	1,525,313		$	1,606,155		$	1,626,953
Financial Liabilities:
Deposits (3)		$	1,282,232		$	1,294,690		$	1,362,619		$	1,389,629
Borrowed funds plus accrued interest payable (3)			57,570			57,260			62,930			62,448
Accrued interest payable on deposits (3)			1,508			1,508			2,379			2,379
Commitments to lend (3)			408			408			386			386
Total Financial Liabilities		$	1,341,718		$	1,353,866		$	1,428,314		$	1,454,842
Net Financial Assets		$	188,346		$	171,447		$	177,841		$	172,111
-1	We consider these fair value measurements to be Level 1.
-2	We consider these fair value measurements to be Level 2, except for our corporate security investments held to maturity, which are considered to be Level 3.
-3	We consider these fair value measurements to be Level 3.
The following methods and assumptions were used to estimate the fair value of financial instruments.
Cash and Equivalents and Time Deposits with Banks - Carrying value approximated estimated fair value because of the relatively short time between the origination of the instrument and its expected realization.
Securities - Except for investments in corporate securities, the estimated fair value for our securities held to maturity and available for sale was obtained from third-party brokers who provided quoted prices derived from active markets for identical or similar securities. The estimated fair value of our corporate security investments, which did not have an active trading market, were obtained from a third-party pricing service, which used a complex valuation model that factored in numerous assumptions and data, including anticipated discounts related to illiquid trading markets, and credit and interest rate risk. The estimated fair value of our investments in FRB and FHLB stock approximated carrying value since the securities were redeemable at cost.
Loans Receivable - The estimated fair value of non-impaired loans was based on a discounted cash flow analysis using discount rates which we believe a third party would require as a reasonable rate of return for loans in our portfolio with similar terms and credit quality. The estimated fair value of impaired loans was approximated to be their net carrying value, net of any specific reserve, as of the dates indicated. We can make no assurance that our perception and quantification of the factors we used in determining the estimated fair value of our loans, including our estimate of perceived credit risk, would be viewed in the same manner as that of a potential investor. Therefore, changes in any of our assumptions could cause the fair value estimates of our loans to deviate substantially.
Deposits - The estimated fair value of deposits with no stated maturity, such as savings, money market, checking and noninterest-bearing demand deposit accounts approximated carrying value since these deposits are payable on demand. The estimated fair value of certificates of deposit (CDs) was based on a discounted cash flow analysis using a discount rate estimated from comparison to interest rates offered by INB as of the dates indicated for CDs with similar remaining maturities. We can make no assurance that this discount rate would be the same used by a potential purchaser. Therefore, any changes in the discount rate could cause their fair value to deviate substantially.
Borrowed Funds and Accrued Interest Payable - The estimated fair value of borrowed funds and related accrued interest payable was based on a discounted cash flow analysis. The discount rate used in the present value computation was estimated by comparison to what we believe to be our incremental borrowing rate for similar arrangements.
All Other Financial Assets and Liabilities - The estimated fair value of accrued interest receivable and accrued interest payable on deposits approximated their carrying values since these instruments have a relatively short time before they are realized or satisfied as the case may be. The estimated fair value of loan fees receivable is based on a discounted cash flow analysis using the same discount rate that was used to value non-impaired loans. The carrying amounts of commitments to lend approximated estimated fair value. Estimated fair value was based on fees charged to enter into similar agreements, taking into account the remaining terms of the agreements and the counter party’s credit standing.

Holding_Company_Financial_Info

Holding Company Financial Information	12 Months Ended
	Dec. 31, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Holding Company Financial Information	'
	21. Holding Company Financial Information
	The following IBC (parent company only) condensed financial information should be read in conjunction with the other notes to the consolidated financial statements in this report.
	Condensed Balance Sheets
			At December 31,
	($ in thousands)		2013			2012
	ASSETS
	Cash and due from banks		$	319		$	46
	Short-term investments			2,241			8,070
	Total cash and cash equivalents			2,560			8,116
	Loans receivable (net of allowance for loan losses of $50)			1,777			2,753
	Investment in consolidated subsidiaries			240,918			254,815
	Investment in unconsolidated subsidiaries - Intervest Statutory Trusts			1,702			1,702
	Deferred income tax asset			6,800			5,748
	Deferred debenture offering costs, net of amortization			742			779
	All other assets			220			388
	Total assets		$	254,719		$	274,301
	LIABILITIES
	Debentures payable - capital securities		$	56,702		$	56,702
	Accrued interest payable on debentures			868			6,228
	All other liabilities			158			424
	Total liabilities			57,728			63,354
	STOCKHOLDERS’ EQUITY
	Preferred equity, net of preferred stock discount			—			24,624
	Common equity			196,991			186,323
	Total stockholders’ equity			196,991			210,947
	Total liabilities and stockholders’ equity		$	254,719		$	274,301
	Condensed Statements of Earnings
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	Interest income		$	129		$	264		$	475
	Interest expense			1,679			1,848			2,072
	Net interest expense			(1,550	)		(1,584	)		(1,597	)
	Provision for loan losses			—			—			290
	Noninterest income			5			5			8
	Noninterest expenses			745			773			816
	Loss before credit for income taxes			(2,290	)		(2,352	)		(2,695	)
	Credit for income taxes			1,052			1,080			1,237
	Net loss before earnings of subsidiary			(1,238	)		(1,272	)		(1,458	)
	Equity in undistributed earnings of Intervest National Bank			15,732			13,494			12,704
	Consolidated net earnings			14,494			12,222			11,246
	Preferred stock dividend requirements and discount amortization (1)			1,057			1,801			1,730
	Consolidated net earnings available to common stockholders		$	13,437		$	10,421		$	9,516
	-1	Represents dividend requirements on preferred stock and amortization of related preferred stock discount.
	Condensed Statements of Cash Flows
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	OPERATING ACTIVITIES
	Consolidated net earnings		$	14,494		$	12,222		$	11,246
	Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:
	Equity in earnings of subsidiary			(15,732	)		(13,494	)		(12,704	)
	Cash dividends from subsidiary			31,000			—			—
	(Decrease) increase in accrued interest payable on debentures			(5,360	)		1,867			2,099
	All other, net change			(1,460	)		(1,116	)		(926	)
	Net cash provided by (used in) operating activities			22,942			(521	)		(285	)
	INVESTING ACTIVITIES
	Return of capital from subsidiary			—			—			229
	Net decrease in loans receivable			981			45			3,884
	Purchase of premises and equipment			(154	)		—			—
	Net cash provided by investing activities			827			45			4,113
	FINANCING ACTIVITIES
	Net (decrease) increase in mortgage escrow funds payable			(84	)		44			(217	)
	Redemption of preferred stock			(24,813	)		—			—
	Cash dividends paid to preferred stockholders			(5,068	)		—			—
Proceeds from issuance of common stock upon exercise of options			61			—			—
Excess tax benefit from exercise of options and vesting of restricted stock			579			—			—
Net cash (used in) provided by financing activities			(29,325	)		44			(217	)
Net (decrease) increase in cash and cash equivalents			(5,556	)		(432	)		3,611
Cash and cash equivalents at beginning of year			8,116			8,548			4,937
Cash and cash equivalents at end of year		$	2,560		$	8,116		$	8,548
SUPPLEMENTAL DISCLOSURES
Cash paid for interest		$	7,002		$	—		$	—
Cash paid for (received from refunds of) income taxes, net			—			—			(43	)
Transfer of loans from subsidiary			—			—			7,437
Transfer of all other net assets from subsidiary			—			—			1,030
Subsidiary’s compensation expense related to equity awards			823			1,194			326
Preferred dividend requirements and amortization of preferred stock discount			1,057			1,801			1,730

Selected_Quarterly_Financial_D

Selected Quarterly Financial Data	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Selected Quarterly Financial Data	'
	22. Selected Quarterly Financial Data (Unaudited)
	The following is a summary of our unaudited interim results of operations and other period-end selected information by quarter for the years ended December 31, 2013 and 2012.
		2013
	($ in thousands, except per share amounts)	Q1			Q2			Q3		Q4
	Interest and dividend income	$	16,249		$	15,623		$	15,624	$	16,120
	Interest expense		7,245			7,048			6,794		6,023
	Net interest and dividend income		9,004			8,575			8,830		10,097
	(Credit) provision for loan losses		(1,000	)		(750	)		250		950
	Net interest and dividend income after (credit) provision for loan losses		10,004			9,325			8,580		9,147
	Noninterest income		743			702			901		2,600
	Noninterest expenses:
	Provision for real estate losses		629			76			250		150
	Real estate expenses (income), net		(986	)		(346	)		212		284
	Operating expenses		4,138			3,954			3,862		3,630
	Earnings before provision for income taxes		6,966			6,343			5,157		7,683
	Provision for income taxes		3,075			2,804			2,300		3,476
	Net earnings		3,891			3,539			2,857		4,207
	Preferred dividend requirements and discount amortization		462			326			269		—
	Net earnings available to common stockholders	$	3,429		$	3,213		$	2,588	$	4,207
	Basic earnings per common share	$	0.16		$	0.14		$	0.12	$	0.19
	Diluted earnings per common share		0.16			0.14			0.12		0.19
	Cash dividends paid per common share		—			—			—		—
	Total assets	$	1,627,787		$	1,596,639		$	1,584,239	$	1,567,796
	Total cash, short-term investments and security investments		507,665			512,573			461,197		423,216
	Total loans, net of unearned fees		1,081,482			1,056,191			1,100,277		1,127,522
	Total deposits		1,318,215			1,293,175			1,298,403		1,282,232
	Total borrowed funds and related accrued interest payable		63,373			56,760			57,165		57,570
	Total stockholders’ equity		215,265			211,775			192,288		196,991
		2012
	($ in thousands, except per share amounts)	Q1			Q2			Q3		Q4
	Interest and dividend income	$	20,698		$	19,706		$	19,082	$	17,798
	Interest expense		10,740			10,001			9,223		8,103
	Net interest and dividend income		9,958			9,705			9,859		9,695
	Provision for loan losses		—			—			—		—
	Net interest and dividend income after provision for loan losses		9,958			9,705			9,859		9,695
	Noninterest income		1,125			1,406			1,187		2,476
	Noninterest expenses:
	Provision for real estate losses		511			1,397			1,025		1,135
	Real estate expenses, net		460			479			883		324
	Operating expenses		4,164			4,149			4,160		4,195
	Earnings before provision for income taxes		5,948			5,086			4,978		6,517
	Provision for income taxes		2,694			2,326			2,300		2,987
	Net earnings		3,254			2,760			2,678		3,530
	Preferred dividend requirements and discount amortization		444			448			453		456
	Net earnings available to common stockholders	$	2,810		$	2,312		$	2,225	$	3,074
	Basic earnings per common share	$	0.13		$	0.11		$	0.1	$	0.14
	Diluted earnings per common share		0.13			0.11			0.1		0.14
	Cash dividends paid per common share		—			—			—		—
	Total assets	$	1,909,052		$	1,862,110		$	1,751,880	$	1,665,792
	Total cash, short-term investments and security investments		691,205			667,509			546,397		518,493
	Total loans, net of unearned fees		1,155,437			1,137,780			1,155,171		1,107,466
	Total deposits		1,599,653			1,554,615			1,432,209		1,362,619
	Total borrowed funds and related accrued interest payable		72,064			72,528			69,487		62,930
	Total stockholders’ equity		201,051			204,121			207,108		210,947

Description_of_Business_and_Su1

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Principles of Consolidation, Basis of Presentation and Use of Estimates	'
	Principles of Consolidation, Basis of Presentation and Use of Estimates
	The consolidated financial statements in this report (which may also be referred to as “financial statements” throughout this report) include the accounts of IBC and its subsidiary. All significant intercompany balances and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior year amounts to conform to the current year’s presentation. Our accounting and reporting policies conform to Generally Accepted Accounting Principles (“GAAP”) and to general practices within the banking industry.
	In preparing the consolidated financial statements, we are required to make estimates and assumptions that affect the reported amounts of our assets, liabilities and disclosure of our contingent liabilities as of the date of the consolidated financial statements, and revenues and expenses during the reporting periods. Actual results could differ from those estimates. Estimates that are particularly susceptible to significant change currently relate to the determination of our allowance for loan losses, valuation allowance for real estate losses, other than temporary impairment assessments of our security investments and the need for and amount of a valuation allowance for our deferred tax asset. These estimates involve a higher degree of complexity and subjectivity and require assumptions about highly uncertain matters.
Cash Equivalents	'
	Cash Equivalents
	For purposes of reporting cash flows, our cash equivalents include cash and balances due from banks, federal funds sold (generally sold for one-day periods) and other short-term investments that have maturities of three months or less from the time of purchase.
Securities	'
	Securities
	General. Investments in debt securities for which we have the ability and intent to hold until maturity are classified as held to maturity (“HTM”) and are carried at cost, adjusted for accretion of discounts and amortization of premiums, which are recognized into interest income using the effective interest method over their contractual lives. Securities that are held for indefinite periods of time which we intend to use as part of our asset/liability management strategy, or that may be sold in response to changes in interest rates or other factors, are classified as available for sale (“AFS”) and are carried at fair value. Unrealized gains and losses on securities available for sale, net of related income taxes, are reported as a separate component of comprehensive income. Realized gains and losses from sales of securities are determined using the specific identification method. We do not purchase securities for the purpose of engaging in trading activities.
	Impairment. We evaluate our security investments for other than temporary impairment (“OTTI”) at least quarterly or more frequently when conditions warrant such evaluation. Impairment is assessed at the individual security level. We consider an investment security to be impaired if, after a review of available evidence, the full collection of our principal investment and interest over the life of the security is no longer probable. The assessment for and the amount of impairment requires the exercise of considerable judgment by us and is entirely an estimate and not a precise determination.
	Our impairment evaluation process considers factors such as the expected cash flows of the security, severity, length of time and anticipated recovery period of the cash shortfalls, recent events specific to the issuer, including investment downgrades by rating agencies and current and anticipated economic and regulatory conditions of its industry, and the issuer’s financial condition, capital strength and near-term prospects. We also consider our intent and ability to retain the security for a period of time sufficient to allow for a recovery in fair value, or until maturity. Among the factors that we consider in determining our intent and ability to retain the security is a review of our capital adequacy, interest rate risk position and liquidity. If it is deemed that OTTI has occurred, the security is written down to a new cost basis and the resulting loss is charged to operations as a component of noninterest income.
	INB is a member of the Federal Home Loan Bank of New York (FHLB) and Federal Reserve Bank of New York (FRB) and is required hold a certain level capital stock of each entity based on various criteria. These investments are carried at cost and are also periodically reviewed for OTTI.
Loans Receivable	'
	Loans Receivable
	General. Loans for which we have the intent and ability to hold for the foreseeable future or until maturity or satisfaction are carried at their outstanding principal net of chargeoffs, the allowance for loan losses, unamortized discounts and deferred loan fees or costs. Loan origination and commitment fees, net of certain costs, are deferred and amortized to interest income as an adjustment to the yield of the related loans over the contractual life of the loans using the interest method. When a loan is paid off or sold, or if a commitment expires unexercised, any unamortized net deferred amount is credited or charged to operations.
	Loans are placed on nonaccrual status when principal or interest becomes 90 days or more past due or earlier in certain cases unless the loan is well secured and in the process of collection. Past due status is based on contractual terms of the loan. When a loan is placed on nonaccrual status, all interest accrued but not collected is reversed against interest income and amortization of net deferred fee income is discontinued. Interest payments received on loans in nonaccrual status are recognized as income on a cash basis unless future collections of principal are doubtful, in which case the payments received are applied as a reduction of principal.
	Loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured. For loans that have been partially charged off, if the remaining book balance of the loan is deemed fully collectible, interest income is recognized on a cash basis but limited to that which would have been accrued on the recorded balance at the contractual rate. Any cash interest received over this limit is recorded as recoveries of prior charge offs until these chargeoffs have been fully recovered.
	Segments. We consider our loan portfolio to be comprised of two segments - (i) real estate loans (which is comprised of loans secured by commercial real estate and multifamily (5 or more units) real estate, loans secured by vacant land and loans secured by 1-4 family real estate) and (ii) all other loans (which is comprised of personal and business loans, both secured and unsecured). Each segment has different risk characteristics and methodologies for assessing risk.
	Commercial and multifamily real estate loans are generally considered to have more credit risk than traditional single family residential loans because these loans tend to involve larger loan balances and their repayment is typically dependent upon the successful operation and management of the underlying real estate. Included in this category are loans we originate on vacant or substantially vacant properties and owner-occupied properties, all of which typically have limited or no income streams and depend upon other sources of cash flow from the borrower for repayment, which add an additional element of risk. Our land loans normally have no income streams and depend upon other sources of cash flow from the borrower for repayment. Our 1-4 family loans consist almost entirely of loans secured by individual condominium dwelling units. We normally make these loans to investors who purchase multiple condo units that remain unsold after a condo conversion or the unsold units in a new condo development. The units are normally rented for a number of years until the economy improves and the units can be sold as was the original intention. Nearly all of these loans are in our Florida market. Although these loans are classified necessarily as loans secured by 1-4 family real estate as required by regulatory guidance, they are underwritten in accordance with our multifamily underwriting polices and their risk characteristics are essentially the same as our multifamily real estate lending and we risk weight them for regulatory capital purposes at 100%. All the above loans require ongoing evaluation and monitoring since they may be affected to a greater degree by adverse conditions in the real estate markets or the economy or changes in government regulation.
	Our real estate loans typically provide for periodic payments of interest and principal during the term of the loan, with the remaining principal balance and any accrued interest due at the maturity date. Most of these loans provide for balloon payments at maturity, which means that a substantial part of or the entire original principal amount is due in one lump sum payment at maturity. If the net revenue from the property is not sufficient to make all debt service payments due on the loan or, if at maturity or the due date of any balloon payment, the owner of the property fails to raise the funds (through refinancing the loan, sale of the property or otherwise) to make the lump sum payment, we could sustain a loss on our loan. As part of our written policies for real estate loans, loan-to-value ratios (the ratio that the original principal amount of the loan bears to the lower of the purchase price or appraised value of the property securing the loan at the time of origination) on loans originated by us typically do not exceed 80% and in practice, rarely exceed 75%. Debt service coverage ratios (the ratio of the net operating income generated by the property securing the loan to the required debt service) on multi-family and commercial real estate loans originated typically are not less than 1.2 times. As noted earlier, we may originate mortgage loans on vacant or substantially vacant properties and vacant land for which there is limited or no cash flow being generated by the operation of the underlying real estate. We may also require personal guarantees from the principals of our borrowers as additional security, although loans are often originated on a limited recourse basis. In originating loans, we consider the ability of the net operating income generated by the real estate to support the debt service, the financial resources, income level and managerial expertise of the borrower, the marketability of the property and our lending experience with the borrower. Our loans are not insured or guaranteed by governmental agencies. In the event of a default, our ability to recover our investment is dependent upon the market value of the mortgaged property.
	The “all other loans” segment is comprised of a small number of business and consumer loans that are extended for various purposes, including lines of credit, personal loans, and personal loans collateralized by deposit accounts. Repayment of consumer loans is primarily dependent on the personal income of the borrowers, which can be impacted by economic conditions in their market areas such as unemployment levels. Loans to businesses and consumers are extended after a credit evaluation, including the creditworthiness of the borrower, the purpose of the credit, and the secondary source of repayment. Risk is mitigated somewhat by the fact that the loans are of smaller individual amounts.
	Risk ratings. We categorize our loans into various risk categories (discussed below) based on an individual analysis of each loan’s quantitative factors and other relevant information, including: an analysis of the underlying collateral’s appraised value and its actual cash flows, with emphasis on projected or normalized cash flows in cases where the collateral currently has no or inadequate cash flows to service the debt; the ability of the borrowers to service their debt from other sources, including whether they have personally guaranteed the loan and the strength of that guaranty, which takes into account a review of their current personal financial information; credit and loan underwriting documentation; and other available pertinent information about the borrower or the collateral, such as an annual property inspection. All of our loans are assigned a risk grade upon based on the timely review, interpretation of and conclusions on the above data as received by us.
	Loans are normally classified as pass credits until they become past due or management becomes aware of deterioration in cash flows and or the credit worthiness of the collateral or the borrower based on the information we collect and monitor. All of our pass-rated loans our generally reviewed annually to determine if they are appropriately classified. Loans rated substandard or special mention are reviewed at least quarterly or more often in some cases to determine if they are appropriately classified. Further, during the renewal process of any maturing loan, as well as if any loan becomes past due, the loan’s risk rating is also reviewed for appropriateness.
	Our internally assigned risk grades and a general summary of the factors that determine the ratings are as follows:
	Pass – Loan is normally current and its primary source of repayment is satisfactory, with secondary sources adequate and very likely to be realized if necessary. This category also contains loans where the underlying collateral is not producing cash flows or is producing in-adequate cash flows to service the loan’s required payments (such as in cases where the collateral is a vacant or substantially vacant building or land) and such payments are being made by the borrower’s other sources of funds. In many cases, the borrower or its principals has guaranteed the loan and or deposited escrow funds with us to cover the loan’s contractual payments for a portion of the loan term.
	Special Mention – Loan is normally current but has one or more potential weaknesses that deserve close attention. If left uncorrected, these potential weaknesses may result in the deterioration of the loan’s repayment prospects or our credit position at some future date.
	Substandard – Loan is inadequately protected by the current worth and paying capacity of the borrower or of the underlying collateral. Such loans have a well-defined weakness or weaknesses that jeopardize the full repayment of the loan. These loans have the distinct possibility that we will sustain some loss if the deficiencies are not corrected.
	Doubtful – Loan has all the weaknesses inherent in one classified substandard with the added characteristics that the weaknesses make collection or liquidation in full, on the basis of currently existing facts, conditions, and values, highly questionable and improbable.
	Loss – Loan is considered uncollectible and of such little value that continuance as an asset is not warranted. This classification does not mean that the asset has absolutely no recovery or salvage value, but rather it is not practical or desirable to defer writing off this basically worthless asset even though partial recovery may be occur in the future.
	Restructured Loans (TDRs). A TDR is a loan that we have restructured, for economic or legal reasons related to a borrower’s financial difficulties, and for which we have granted certain concessions to the borrower that we would not otherwise have considered. In order to be considered a TDR, we must conclude that the restructuring was to a borrower who is experiencing financial difficulties and the restructured loan constitutes a “concession”. We define a concession as a modification of existing terms granted to a borrower for economic or legal reasons related to the borrower’s financial difficulties. Concessions include modifying the original loan terms to reduce or defer cash payments required as part of the loan agreement, including but not limited to: a reduction of the stated interest rate for the remaining original life of the debt; an extension of the maturity date or dates at an interest rate lower than the current market rate for new debt with similar risk characteristics, a reduction of the face amount or maturity amount of the debt, or a reduction of accrued interest owed on the debt. A loan that is extended or renewed at a stated interest rate equal to the current interest rate for a new loan originated by us with similar risk is not reported as a TDR.
	In determining whether the borrower is experiencing financial difficulties, we consider, among other things, whether the borrower is in default on its existing loan, or is in an economic position where it is probable the borrower will be in default on its loan in the foreseeable future without a modification, including whether, without the modification, the borrower cannot obtain sufficient funds from other sources at an effective interest rate equal to the current market rate for similar debt for a non-troubled debtor. TDR loans are reviewed for specific impairment in accordance with our allowance for loan loss methodology with respect to impaired loans. A TDR that is on nonaccrual status is returned to an accrual status if ultimate collectability of the entire contractual principal is assured and the borrower has demonstrated satisfactory payment performance either before or after the restructuring, usually consisting of a six-month period.
	Impaired Loans. Loans are deemed to be impaired when, based upon current information and events, it is probable that we will be unable to collect both principal and interest due according to the loan’s contractual terms. We consider a variety of factors in determining whether a loan is impaired, including (i) any notice from the borrower that the borrower will be unable to repay all principal and interest amounts contractually due under the loan agreement, (ii) any delinquency in the principal and/or interest payments other than minimal delays or shortfalls in payments, and (iii) other information known by us that would indicate the full repayment of principal and interest is not probable. We generally consider delinquencies of 60 days or less to be minimal delays, and accordingly we do not consider such delinquent loans to be impaired in the absence of other indications.
	Our impaired loans normally consist of loans on nonaccrual status and TDRs. Generally, impairment for all of our impaired loans is calculated on a loan-by-loan basis using either the estimated fair value of the loan’s collateral less estimated selling costs (for collateral dependent loans) or the present value of the loan’s cash flows (for non-collateral dependent loans). Any calculated impairment is recognized as a valuation allowance within the overall allowance for loan losses and a charge through the provision for loan losses. We may charge off any portion of the impaired loan with a corresponding decrease to the valuation allowance when such impairment is deemed uncollectible and confirmed as a loss. The net carrying amount of an impaired loan (net of the valuation allowance) does not at any time exceed the recorded investment in the loan.
Allowance for Loan Losses and Loan Chargeoffs	'
	Allowance for Loan Losses and Loan Chargeoffs
	The allowance for loan losses, which includes a valuation allowance for impaired loans, is netted against loans receivable and is increased by provisions charged to operations and decreased by chargeoffs (net of recoveries). The adequacy of the allowance is evaluated at least quarterly with consideration given to various factors beginning with our historical lending loss rate for each major loan type (exclusive of the impact of any transaction that is unusual and deemed not reflective of normal charge-off history).
	The historical loss rate is then adjusted either upward or downward based on a review of the following qualitative factors and their estimated impact to the historical loss rate: (i) the size of our loans; (ii) concentrations of our loans; (iii) changes in the quality of our review of specific problem loans, including loans on nonaccrual status, and estimates of fair value of the underlying properties; (iv) changes in the volume of our past due loans, nonaccrual loans and adversely classified assets. (iv) specific problem loans and estimates of fair value of the related collateral; (v) adverse situations which may affect our borrowers’ ability to repay; (vi) changes in national, regional and local economic and business conditions and other developments that may affect the collectability of our loan portfolio, including impacts of political, regulatory, legal and competitive changes on the portfolio; (vii) changes to our lending policies and procedures, underwriting standards, risk selection (loan volumes and loan terms) and to our collection, loan chargeoff and recovery practices; and (viii) changes in the experience, ability and depth of our lending management and other relevant staff.
	We fully or partially charge off an impaired loan when such amount has been deemed uncollectible and confirmed as a loss. In the case of impaired collateral dependent loans, we normally charge-off the portion of the loan’s recorded investment that exceeds the appraised value (net of estimated selling costs) of its underlying collateral. The remaining portion of the valuation allowance that we have provided and maintain on all of our impaired loans for the difference between the net appraised value and our internal estimate of fair value of the collateral is charged off only when such amount has been confirmed as a loss, either through the receipt of future appraisals or through our quarterly evaluation of the factors described below.
	Consistent with regulatory guidance, we normally maintain a specific valuation allowance on each of our impaired loans. We believe it is prudent to do so because the process of estimating real estate values is imprecise and subject to changing market conditions which could cause fluctuations in estimated values. Estimates are subjective in nature, involve uncertainties and matters of significant judgment and therefore, cannot be determined with precision. Changes in any of the market assumptions could cause fair value estimates to deviate substantially. Furthermore, commercial real estate markets and national and local economic conditions remain weak; unemployment rates and vacancy rates in retail and office properties continue to be high; and the timing of the resolution of impaired loans in many cases remains uncertain, which increases the negative impact to the portfolio from further declines in real estate values.
	Regulatory guidelines require that the appraised value of collateral should be used as a starting point for determining its estimated fair value. An institution should also consider other factors and events in the environment that may affect the current fair value of the collateral since the appraisal was performed. The institution’s experience with whether the appraised values of impaired collateral-dependent loans are actually realized should also be taken into account. In addition, the timing of when the cash flows are expected to be received from the underlying collateral could affect the fair value of the collateral if the timing was not contemplated in the appraisal. The consideration of all the above generally results in the appraised value of the collateral being greater than the institution’s estimate of the collateral’s fair value, less estimated costs to sell. As a consequence, an institution may necessarily still have a specific reserve on an impaired loan (whether or not a charge off has been taken) for the amount by which the institution’s estimated fair value of the collateral, less estimated costs to sell, is believed to be lower than its appraised value. As a result, we maintain a specific valuation allowance on all of our impaired loans for the reasons described above.
	We estimate the fair value of the properties that collateralize our impaired loans based on a variety of information, including third party appraisals and our management’s judgment of other factors. Our internal policy is to obtain externally prepared appraisals as follows (i) for all impaired loans; (ii) for all restructured or renewed loans; (iii) upon classification or downgrade of a loan; (iv) upon completion of foreclosure and acquisition of the collateral property; and at least annually thereafter for all impaired and substandard rated loans and real estate owned through foreclosure.
	In addition, we also consider the knowledge and experience of our two senior lending officers (our Chairman and INB’s President) and INB’s Chief Credit Officer related to values of properties in our lending markets. They take into account various information, including: discussions with real estate brokers and interested buyers, local and national real estate market data provided by third parties; the consideration of the type, condition, location, demand for and occupancy of the specific collateral property and current economic and real estate market conditions in the area the property is located in assessing our internal estimates of fair value.
	Our regulators, as an integral part of their examination process, also periodically review our allowances for loan and real estate losses. Accordingly, we may be required to take chargeoffs and/or recognize additions to these allowances based on the regulators’ judgment concerning information available to them during their examination. There were no changes to our methodology for the allowance for loan loss during the reporting periods in this report
Premises and Equipment	'
	Premises and Equipment
	Land is carried at cost. Buildings, leasehold improvements and furniture, fixtures and equipment are carried at cost, less accumulated depreciation and amortization. Depreciation is computed using the straight-line method over the estimated useful life of the asset. Leasehold improvements are amortized using the straight-line method over the terms of the related leases, or the useful life of the asset, whichever is shorter. Maintenance, repairs and minor improvements are expensed as incurred, while major improvements are capitalized.
Deferred Debenture Offering Costs	'
	Deferred Debenture Offering Costs
	Costs relating to offerings of our debentures consisting primarily of underwriters’ commissions are amortized over the life of the debentures. At December 31, 2013, these costs totaled approximately $0.7 million, net of accumulated amortization of $0.4 million. At December 31, 2012, these costs totaled approximately $0.8 million, net of accumulated amortization of $0.3 million.
Foreclosed Real Estate and Valuation Allowance For Real Estate Losses	'
	Foreclosed Real Estate and Valuation Allowance For Real Estate Losses
	Real estate that we acquire through loan foreclosure or similar proceedings is held for sale. At the time we acquire the property, the related loan is transferred from the loan portfolio to foreclosed real estate at the estimated fair value of the property less estimated selling costs. Such amount becomes the new cost basis of the property. Adjustments made to reduce the carrying value at the time of transfer are charged to the allowance for loan losses.
	We may periodically adjust the carrying values of the real estate to reflect decreases in its estimated fair value through a charge to earnings (recorded as a provision for real estate losses) and an increase to the valuation allowance for real estate losses. As the properties are sold, the valuation allowance associated with the property, if any, is charged off. We determine the estimated fair value of foreclosed real estate at least quarterly by performing market valuations of the properties, which normally consist of obtaining externally prepared appraisals at least annually for every property, as well as performing reviews of economic and real estate market conditions in the local area where the property is located, including taking into consideration discussions with real estate brokers and interested buyers, in order to determine if a valuation allowance is needed to reflect any decrease in the estimated fair value of the property since acquisition.
	Revenue and expenses from the operations of foreclosed real estate are included in the caption “Real Estate Activities” in the consolidated statements of earnings. This line item is comprised of real estate taxes, repairs and maintenance, insurance, utilities, legal fees and other charges (net of any rental income earned from the operation of the property) that are required in protecting our interest in real estate acquired through foreclosure and various properties collateralizing our nonaccrual loans.
Stock-Based Compensation	'
	Stock-Based Compensation
	We recognize the cost of our employee and director services received in exchange for awards of our equity instruments (such as restricted stock and stock options grants) based on the grant-date fair value of the awards. Compensation cost related to the awards is recognized on a straight-line basis over the requisite service period, which is normally the vesting period of the grants. The fair value of options granted is estimated using the Black-Scholes option-pricing model based on various assumptions that are described in note 13. The fair value of restricted stock grants is based on the closing market value of the stock as reported on the Nasdaq Stock Market on the grant date.
Advertising Costs	'
	Advertising Costs
	Advertising costs are expensed as incurred and amounted to $23,000 in 2013, $17,000 in 2012 and $26,000 in 2011.
Income Taxes	'
	Income Taxes
	Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of the enacted tax law to our taxable income or loss. Deferred income taxes are recognized for the tax consequences of temporary differences by applying enacted statutory tax rates, applicable to future years, to differences between the financial statement carrying amounts and the tax basis of existing assets and liabilities The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income tax expense in the period that includes the enactment date.
	Deferred tax assets are reduced by a valuation allowance if, based on the weight of evidence available, it is more likely than not that some portion or all of a deferred tax asset will not be realized. Certain tax benefits attributable to stock options, restricted stock and warrants are credited to additional paid-in-capital. Accruals of interest and penalties related to unrecognized tax benefits are recognized in income tax expense.
	Uncertain tax positions are recognized if it is more likely (a likelihood of more than 50 percent) than not that the tax position will be realized or sustained upon examination. A tax position that meets the more-likely-than-not recognition threshold is initially and subsequently measured as the largest amount of tax benefit that has a greater than 50 percent likelihood of being realized upon settlement with a taxing authority. The determination of whether or not a tax position has met the more-likely-than-not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management’s judgment. At December 31, 2013, we were not aware of any uncertain tax positions that would have a material effect on our financial statements.
Earnings Per Common Share	'
	Earnings Per Common Share
	Basic earnings per common share is calculated by dividing net earnings available to common stockholders by the weighted-average number of shares of all common stock outstanding during the reporting period. Unvested restricted stock is deemed to be issued and outstanding. Diluted earnings per common share is calculated by dividing net earnings available to common stockholders by the weighted-average number of shares of common stock and dilutive potential common stock shares that may be outstanding in the future. Potential common stock shares consist of shares that may arise from outstanding dilutive common stock warrants and options (the number of which is computed using the “treasury stock method”).
	When applying the treasury stock method, we add: the assumed proceeds from stock option and warrant exercises; the tax benefit that would have been credited to additional paid-in capital assuming exercise of non-qualified stock options and warrants and the unamortized compensation costs related to unvested shares of stock options and warrants. We then divide this sum by our average stock price for the period to calculate shares assumed to be repurchased. The excess of the number of shares issuable over the number of shares assumed to be repurchased is added to basic weighted average common shares to calculate diluted earnings per common share.
Comprehensive Earnings	'
	Comprehensive Income
	Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net earnings. However, certain changes in assets and liabilities, such as unrealized gains and losses on available-for-sale securities, are reported as a separate component of the stockholders’ equity section of the consolidated balance sheet, such items along with net earnings, are components of comprehensive income.
Off-Balance Sheet Financial Instruments	'
	Off-Balance Sheet Financial Instruments
	We enter into off-balance sheet financial instruments consisting of commitments to extend credit, unused lines of credit and from time to time standby letters of credit. Such financial instruments are recorded in the consolidated financial statements when they are funded or related fees are received.
Recent Accounting Standards Update	'
	Recent Accounting Standards Update
	In July 2012, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) 2012-02, “Testing Indefinite-Lived Intangible Assets for Impairment,” which, among other things, gives an entity the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that an indefinite-lived intangible asset is impaired. We adopted this ASU on January 1, 2013, and since we do not have intangible assets, it had no impact on our financial statements.
	In January 2013, the FASB issued ASU No. 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities,” which limits the scope of the new balance sheet offsetting disclosures in ASU 2011-11 to derivatives, repurchase agreements, and securities lending transactions to the extent that they are (1) offset in the financial statements or (2) subject to an enforceable master netting arrangement or similar agreement. We adopted this ASU on February 1, 2013 and it had no impact on our financial statements.
	In February 2013, the FASB Issued ASU No. 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income,” which requires entities to present information about reclassification adjustments from accumulated other comprehensive income in their annual financial statements in a single note or on the face of the financial statements. We adopted this ASU on March 1, 2013 and it had no impact on our financial statements.
	In February 2013, the FASB Issued ASU No. 2013-04, “Obligations Resulting from Joint and Several Liability Arrangements for Which the Total Amount of the Obligation Is Fixed at the Reporting Date”. ASU 2013-04 provides guidance for the recognition, measurement, and disclosure of obligations resulting from joint and several liability arrangements for obligations within the scope of this ASU, which is effective January 1, 2014. Upon adoption, we do not expect this ASU to impact our financial statements.
	In July 2013, the FASB issued ASU No. 2013-10, “Inclusion of the Fed Funds Effective Swap Rate (or Overnight Index Swap Rate) as a Benchmark Interest Rate for Hedge Accounting Purposes”. ASU No. 2013-10 permits the use of the Fed Funds Effective Swap Rate (OIS) to be used as a U.S. benchmark interest rate for hedge account purposes. The amendment is effective prospectively for qualifying new or re-designated hedging relationships entered into on or after July 17, 2013. The adoption of ASU No. 2013-10 did have an impact on our financial statements.
	In July 2013, the FASB issued ASU 2013-11, “Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists,” which among other things, require an unrecognized tax benefit, or a portion of an unrecognized tax benefit, to 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 as denoted within the ASU. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. We are currently evaluating the impact of ASU 2013-11 on our financial statements.

Securities_Held_to_Maturity_an1

Securities Held to Maturity and Available for Sale (Tables)	12 Months Ended
	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]	'
Carrying Value (Amortized Cost) and Estimated Fair Value of Securities Held to Maturity	'
	The carrying value (amortized cost) and estimated fair value of securities held to maturity (“HTM”) are as follows:
	($ in thousands)		Number of			Amortized			Gross			Gross		Estimated		Wtd-Avg			Wtd-Avg		Wtd-Avg
			Securities			Cost			Unrealized			Unrealized		Fair		Yield			Expected		Remaining
									Gains			Losses		Value					Life		Maturity
	At December 31, 2013
	U.S. government agencies (1)			161		$	305,906		$	410		$	4,947	$	301,369		0.94	%	3.0 Yrs		3.8 Yrs
	Residential mortgage-backed (2)			57			77,500			130			1,017		76,613		1.79	%	4.3 Yrs		14.7 Yrs
	State and municipal			1			531			—			6		525		1.25	%	3.2 Yrs		3.3 Yrs
				219		$	383,937		$	540		$	5,970	$	378,507		1.11	%	3.3Yrs		6.0 Yrs
	At December 31, 2012
	U.S. government agencies (1)			165		$	355,244		$	1,109		$	233	$	356,120		0.87	%	1.6 Yrs		4.6 Yrs
	Residential mortgage-backed (2)			48			84,279			651			72		84,858		1.76	%	3.3 Yrs		17.3 Yrs
	State and municipal			1			533			—			3		530		1.25	%	4.2 Yrs		4.3 Yrs
	Corporate (3)			8			3,721			—			3,063		658		2.11	%	20.3 Yrs		20.9 Yrs
				222		$	443,777		$	1,760		$	3,371	$	442,166		1.05	%	2.0 Yrs		7.1 Yrs
	-1	Consisted of debt obligations of U.S. government sponsored agencies (GSEs) - Federal Home Loan Bank (FHLB), Federal Farm Credit Bank (FFCB), Federal National Mortgage Association (FNMA) and Federal Home Loan Mortgage Corporation (FHLMC), which are federally chartered corporations privately owned by shareholders. GSE securities carry no explicit U.S. government guarantee of creditworthiness. Neither principal nor interest payments are guaranteed by the U.S. government nor do they not constitute a debt or obligation of the U.S. government or any of its agencies or instrumentalities other than the applicable GSE. FNMA and FHLMC are under U.S. government conservatorship.
	-2	At December 31, 2013, consisted of $13.6 million of Government National Mortgage Association (GNMA) pass-through certificates, $45.6 million of FNMA participation certificates and $18.3 million of FHLMC participation certificates, compared to $18.7 million, $40.0 million and $25.6 million, respectively, at December 31, 2012. The GNMA pass-through certificates are guaranteed as to the payment of principal and interest by the full faith and credit of the U.S. government while the FNMA and FHLMC certificates have an implied guarantee by such agency as to principal and interest payments.
	-3	Consisted of variable-rate pooled trust preferred securities backed by obligations of companies in the banking industry. Amortized cost at December 2012 is reported net of other than temporary impairment (“OTTI”) charges of $4.2 million. During 2013, an additional $1.0 million of OTTI charges were recorded. In December 2013, these securities were transferred to available for sale and subsequently sold.
Continuous Unrealized Loss Position	'
	The estimated fair values of HTM securities with gross unrealized losses segregated between securities that have been in a continuous unrealized loss position for less than twelve months at the respective dates and those that have been in a continuous unrealized loss position for twelve months or longer are summarized as follows:
	($ in thousands)		Number of			Less Than Twelve Months						Twelve Months or Longer				Total
			Securities			Estimated			Gross			Estimated		Gross		Estimated			Gross
						Fair			Unrealized			Fair		Unrealized		Fair			Unrealized
						Value			Losses			Value		Losses		Value			Losses
	At December 31, 2013
	U.S. government agencies			130		$	233,930		$	4,791		$	7,344	$	156	$	241,274		$	4,947
	Residential mortgage-backed			41			48,862			987			3,284		30		52,146			1,017
	State and municipal			1			525			6			—		—		525			6
				172		$	283,317		$	5,784		$	10,628	$	186	$	293,945		$	5,970
	At December 31, 2012
	U.S. government agencies			53		$	129,365		$	233		$	—	$	—	$	129,365		$	233
	Residential mortgage-backed			14			24,481			72			—		—		24,481			72
	State and municipal			1			530			3			—		—		530			3
	Corporate			8			—			—			658		3,063		658			3,063
				76		$	154,376		$	308		$	658	$	3,063	$	155,034		$	3,371
Summary of Carrying Value (Amortized Cost) and Fair Value of Securities Held to Maturity	'
	The following table is a summary of the carrying value (amortized cost) and estimated fair value of HTM securities at December 31, 2013, by remaining period to contractual maturity (ignoring earlier call dates, if any). The amounts reported in the table also did not consider the effects of possible prepayments or unscheduled repayments. Accordingly, actual maturities may differ from contractual maturities shown in the table.
	($ in thousands)		Amortized			Estimated			Wtd-Avg
			Cost			Fair Value			Yield
	Due in one year or less		$	12,329		$	12,394			1.27	%
	Due after one year through five years			262,878			259,611			0.9
	Due after five years through ten years			56,507			54,962			1.38
	Due after ten years			52,223			51,540			1.87
			$	383,937		$	378,507			1.11	%
Credit Losses Recognized on Securities	'
	The table below provides a roll forward of credit losses recognized on the corporate securities for the periods indicated.
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	Balance at beginning of period		$	4,233		$	3,651		$	3,450
	Additional credit losses on debt securities for which OTTI was previously recognized			964			582			201
	Balance at end of period		$	5,197		$	4,233		$	3,651
Schedule of Corporate Securities Available for Sale	'
	The table below provides information ($ in thousands) regarding the corporate securities as of the date of sale.
	Original		Cumulative			Cumulative			Net			Net Proceeds		Net Gain
	Cost		Cash Payments			OTTI			Carrying			from Sale		on Sale
	Basis		Applied to Cost			Charges			Value
	$8,029		$	(263	)	$	(5,197	)	$	2,569		$	4,050	$	1,481

Loans_Receivable_Tables

Loans Receivable (Tables)	12 Months Ended
	Dec. 31, 2013
Receivables [Abstract]	'
Major Classifications of Loans Receivable	'
	Major classifications of loans receivable are summarized as follows:
			At December 31, 2013								At December 31, 2012
	($ in thousands)		# of Loans				Amount				# of Loans				Amount
	Loans Secured By Real Estate:
	Commercial loans			394			$	838,766				376			$	852,213
	Multifamily loans			138				210,270				142				208,699
	One to four family loans			20				72,064				13				41,676
	Land loans			5				9,178				7				7,167
				557				1,130,278				538				1,109,755
	All Other Loans:
	Business loans			19				1,061				18				949
	Consumer loans			12				211				12				359
				31				1,272				30				1,308
	Loans receivable, gross			588				1,131,550				568				1,111,063
	Deferred loan fees							(4,028	)							(3,597	)
	Loans receivable, net of deferred fees							1,127,522								1,107,466
	Allowance for loan losses							(27,833	)							(28,103	)
	Loans receivable, net						$	1,099,689							$	1,079,363
Summary of Impaired Loans	'
	The tables below summarize certain information regarding our impaired loans as follows:
	($ in thousands)		Recorded Investment by State (1)																							Specific		Total		# of
																										Valuation		Unpaid		Loans
	At December 31, 2013		NY				FL				VA				GA			CT		OH		SD		Total		Allowance (2)		Principal (3)
	Type
	Retail		$	8,223			$	9,005			$	7,828			$	—		$	2,719	$	1,000	$	—	$	28,775	$	3,052	$	36,216		7
	Office Building			—				14,937				—				8,695			—		—		—		23,632		1,947		23,632		3
	Multifamily			—				3,128				—				—			—		—		—		3,128		594		3,128		2
	Land			—				—				—				—			—		—		1,625		1,625		500		1,625		1
	Totals		$	8,223			$	27,070			$	7,828			$	8,695		$	2,719	$	1,000	$	1,625	$	57,160	$	6,093	$	64,601		13
	($ in thousands)		Recorded Investment by State (1)																			Specific		Total		# of
																						Valuation		Unpaid		Loans
	At December 31, 2012		NY				FL				NJ				OH			SD		Total		Allowance (2)		Principal (3)
	Type
	Retail		$	11,837			$	9,005			$	—			$	1,000		$	—	$	21,842	$	1,966	$	27,596		6
	Office Building			—				17,988				883				—			—		18,871		583		19,621		3
	Warehouse			950				—				—				—			—		950		28		950		1
	Mixed-use commercial			8,632				—				500				—			—		9,132		1,248		9,421		4
	Multifamily			—				12,577				—				—			—		12,577		1,542		14,225		6
	Land			515				—				—				—			2,086		2,601		521		2,601		3
	Totals		$	21,934			$	39,570			$	1,383			$	1,000		$	2,086	$	65,973	$	5,888	$	74,414		23
	-1	Represents unpaid principal less partial principal charge offs and interest received and applied as a reduction of principal in certain cases.
	-2	Represents a specific valuation allowance against the recorded investment, which is included as part of our overall allowance for loan losses.
	All impaired loans at the dates indicated in the table had a specific valuation allowance.
	-3	Represents contractual unpaid principal balance (shown for informational purposes only). The borrowers are obligated to pay such amounts.
Other Information Related to Impaired Loans	'
	Other information related to our impaired loans is summarized as follows:
			For the Year Ended December 31,
	($ in thousands)		2013				2012				2011
	Average recorded investment in nonaccrual loans		$	40,345			$	52,199			$	51,356
	Total cash basis interest income recognized on nonaccrual loans			2,265				2,660				2,437
	Average recorded investment in accruing TDR loans			13,918				12,289				5,417
	Total interest income recognized on accruing TDR loans under modified terms			734				739				299
Age Analysis of Loan Portfolio by Segment	'
	Age analysis of our loan portfolio by segment at December 31, 2013 is summarized as follows:
	($ in thousands)		Total				Current				Past Due				Past Due			Past Due		Total		Total
			Portfolio								31-59				60-89			90 or more		Past Due		Classified
											Days				Days			Days				Nonaccrual
	Accruing Loans:
	Commercial real estate		$	802,863			$	796,980			$	1,796			$	—		$	4,087	$	5,883	$	—
	Multifamily			210,270				209,426				844				—			—		844		—
	One to four family			72,064				72,064				—				—			—		—		—
	Land			9,178				9,178				—				—			—		—		—
	All other			1,272				1,271				1				—			—		1		—
	Total accruing loans			1,095,647				1,088,919				2,641				—			4,087		6,728		—
	Nonaccrual Loans (1):
	Commercial real estate			35,903				35,903				—				—			—		—		35,903
	Total nonaccrual loans			35,903				35,903				—				—			—		—		35,903
	Total loans		$	1,131,550			$	1,124,822			$	2,641			$	—		$	4,087	$	6,728	$	35,903
	Age analysis of our loan portfolio by segment at December 31, 2012 is summarized as follows:
	($ in thousands)		Total				Current				Past Due				Past Due			Past Due		Total		Total
			Portfolio								31-59				60-89			90 or more		Past Due		Classified
											Days				Days			Days				Nonaccrual
	Accruing Loans:
	Commercial real estate		$	816,357			$	799,130			$	12,836			$	—		$	4,391	$	17,227	$	—
	Multifamily			198,942				198,942				—				—			—		—		—
	One to four family			41,676				41,676				—				—			—		—		—
	Land			6,882				4,221				2,661				—			—		2,661		—
	All other			1,308				1,308				—				—			—		—		—
	Total accruing loans			1,065,165				1,045,277				15,497				—			4,391		19,888		—
	Nonaccrual Loans (1):
	Commercial real estate			35,856				32,701				—				—			3,155		3,155		35,856
	Multifamily			9,757				7,261				—				—			2,496		2,496		9,757
	Land			285				285				—				—			—		—		285
	Total nonaccrual loans			45,898				40,247				—				—			5,651		5,651		45,898
	Total loans		$	1,111,063			$	1,085,524			$	15,497			$	—		$	10,042	$	25,539	$	45,898
	-1	The amount of nonaccrual loans in the current column included $33.2 million of TDRs at December 31, 2013 and $36.3 million of TDRs at December 31, 2012 for which payments were being made in accordance with their restructured terms, but the loans were maintained on nonaccrual status in accordance with regulatory guidance. The remaining portion at both dates was comprised of certain paying loans classified nonaccrual due to concerns regarding the borrowers’ ability to continue making payments. Interest income from loan payments on all loans in nonaccrual status is recognized on a cash basis, provided the remaining principal balance is deemed collectible.
Information Regarding Credit Quality of Loan Portfolio	'
	Information regarding the credit quality of the loan portfolio based on our internally assigned grades follows:
	($ in thousands)		Pass				Special Mention				Substandard (1)				Total
	At December 31, 2013
	Commercial real estate		$	772,900			$	3,522			$	62,344			$	838,766
	Multifamily			204,298				2,369				3,603				210,270
	One to four family			72,064				—				—				72,064
	Land			7,553				—				1,625				9,178
	All other			1,272				—				—				1,272
	Total loans		$	1,058,087			$	5,891			$	67,572			$	1,131,550
	Allocation of allowance for loan losses		$	20,720			$	169			$	6,944			$	27,833
	At December 31, 2012
	Commercial real estate		$	775,136			$	17,041			$	60,036			$	852,213
	Multifamily			193,738				2,384				12,577				208,699
	One to four family			41,676				—				—				41,676
	Land			4,566				—				2,601				7,167
	All other			1,308				—				—				1,308
	Total loans		$	1,016,424			$	19,425			$	75,214			$	1,111,063
	Allocation of allowance for loan losses		$	20,037			$	443			$	7,623			$	28,103
	-1	Substandard loans consisted of $35.9 million of nonaccrual loans, $13.1 million of accruing TDRs and $18.6 million of other performing loans at December 31, 2013, compared to $45.9 million of nonaccrual loans, $20.1 million of accruing TDRs and $9.2 million of other performing loans at December 31, 2012. At December 31, 2013, we also had one accruing TDR for $0.4 million which was rated pass.
Geographic Distribution of Loan Portfolio	'
	The geographic distribution of the loan portfolio by state follows:
	($ in thousands)		At December 31, 2013								At December 31, 2012
			Amount				% of Total				Amount				% of Total
	New York		$	670,052				59.2	%		$	717,141				64.5	%
	Florida			321,812				28.4				286,619				25.8
	North Carolina			22,611				2				14,256				1.3
	Georgia			18,799				1.7				11,752				1.1
	Pennsylvania			16,898				1.5				10,270				0.9
	New Jersey			15,650				1.4				26,425				2.4
	Kentucky			11,930				1.1				7,512				0.7
	Virginia			11,491				1				11,758				1.1
	South Carolina			9,223				0.8				5,853				0.5
	Connecticut			8,429				0.7				11,216				1
	Tennessee			5,843				0.5				770				0.1
	Michigan			5,599				0.5				450				0
	Ohio			4,703				0.4				2,260				0.2
	Indiana			2,820				0.2				1,098				0.1
	All other states			5,690				0.5				3,683				0.3
			$	1,131,550				100	%		$	1,111,063				100	%
Information Regarding Loans Restructured	'
	Information regarding loans restructured during 2013 and 2012 is as follows:
					Number				Recorded Investment
	($ in thousands)				of Loans				Pre-Modification				Post-Modification
	In 2013		- Commercial real estate - extended maturity date			2			$	9,159			$	9,159
	In 2012		- Commercial real estate - extended maturity date			1			$	5,010			$	5,010
			- Multifamily - extended maturity date			1				1,805				1,805
			- Land - extended maturity date			2				520				520
						4			$	7,335			$	7,335
Distribution of TDRs by Accruing Versus Non-Accruing, by Segment and by Geographic	'
	The distribution of TDRs by accruing versus non-accruing, by loan type and by geographic distribution follows:
	($ in thousands)		At December 31, 2013				At December 31, 2012
	Performing - nonaccrual status		$	33,184			$	36,291
	Performing - accrual status			13,429				20,076
			$	46,613			$	56,367
	Commercial real estate		$	41,860			$	43,685
	Multifamily			3,128				10,081
	Land			1,625				2,601
			$	46,613			$	56,367
	New York		$	8,223			$	18,478
	Florida			27,070				33,920
	New Jersey			—				883
	Georgia			8,695				—
	Ohio			1,000				1,000
	South Dakota			1,625				2,086
			$	46,613			$	56,367

Allowance_for_Loan_Losses_Tabl

Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Allowance for Loan Losses by Loan Type	'
	Activity in the allowance for loan losses by loan type for the periods indicated follows:
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Balance at December 31, 2010		$	21,919		$	11,234		$	122	$	1,553		$	12		$	34,840
	Loan chargeoffs			(7,186	)		(2,412	)		—		—			—			(9,598	)
	Loan recoveries			90			65			—		—			—			155
	Provision (credit) for loan losses			4,333			(39	)		210		516			(2	)		5,018
	Balance at December 31, 2011		$	19,156		$	8,848		$	332	$	2,069		$	10		$	30,415
	Loan chargeoffs			(2,588	)		(564	)		—		—			—			(3,152	)
	Loan recoveries			507			333			—		—			—			840
	Provision (credit) for loan losses			1,976			(1,736	)		788		(1,026	)		(2	)		—
	Balance at December 31, 2012		$	19,051		$	6,881		$	1,120	$	1,043		$	8		$	28,103
	Loan chargeoffs			(1,932	)		(6	)		—		—			—			(1,938	)
	Loan recoveries			1,053			682			—		483			—			2,218
	Provision (credit) for loan losses			231			(2,460	)		1,897		(218	)		—			(550	)
	Balance at December 31, 2013		$	18,403		$	5,097		$	3,017	$	1,308		$	8		$	27,833
Loans Receivable by Segment and Impairment Evaluation and Allowance for Loan Losses	'
	The following table sets forth the balances of our loans receivable by segment and impairment evaluation and the allowance for loan losses associated with such loans at December 31, 2013.
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Loans:
	Individually evaluated for impairment		$	52,407		$	3,128		$	—	$	1,625		$	—		$	57,160
	Collectively evaluated for impairment			786,359			207,142			72,064		7,553			1,272			1,074,390
	Total loans		$	838,766		$	210,270		$	72,064	$	9,178		$	1,272		$	1,131,550
	Allowance for loan losses:
	Individually evaluated for impairment (1)		$	4,999		$	594		$	—	$	500		$	—		$	6,093
	Collectively evaluated for impairment			13,404			4,503			3,017		808			8			21,740
	Total allowance for loan losses		$	18,403		$	5,097		$	3,017	$	1,308		$	8		$	27,833
	-1	See note 3 to financial statements in this report.
	The following table sets forth the balances of our loans receivable by segment and impairment evaluation and the allowance for loan losses associated with such loans at December 31, 2012.
	($ in thousands)		Commercial			Multifamily			One to Four		Land			All Other			Total
			Real Estate						Family
	Loans:
	Individually evaluated for impairment		$	50,795		$	12,577		$	—	$	2,601		$	—		$	65,973
	Collectively evaluated for impairment			801,418			196,122			41,676		4,566			1,308			1,045,090
	Total loans		$	852,213		$	208,699		$	41,676	$	7,167		$	1,308		$	1,111,063
	Allowance for loan losses:
	Individually evaluated for impairment (1)		$	3,825		$	1,542		$	—	$	521		$	—		$	5,888
	Collectively evaluated for impairment			15,226			5,339			1,120		522			8			22,215
	Total allowance for loan losses		$	19,051		$	6,881		$	1,120	$	1,043		$	8		$	28,103
	-1	See note 3 to financial statements in this report.

Premises_and_Equipment_Lease_C1

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income (Tables)	12 Months Ended
	Dec. 31, 2013
Property Plant And Equipment [Abstract]	'
Premises and Equipment	'
	Premises and equipment is as follows:
		At December 31,
	($ in thousands)	2013			2012
	Land	$	1,264		$	1,264
	Buildings		5,214			5,020
	Leasehold improvements		1,786			1,632
	Furniture, fixtures and equipment		1,713			1,770
	Total cost		9,977			9,686
	Less accumulated deprecation and amortization		(5,921	)		(5,808	)
	Net book value	$	4,056		$	3,878

Foreclosed_Real_Estate_and_Val1

Foreclosed Real Estate and Valuation Allowance for Real Estate Losses (Tables)	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Summary of Activity in the Valuation Allowance for Real Estate Losses	'
	Activity in the valuation allowance for real estate losses is as follows:
		For the Year Ended December 31,
	($ in thousands)	2013			2012			2011
	Valuation allowance at beginning of year	$	5,339		$	6,037		$	2,688
	Provision for real estate losses charged to expense		1,105			4,068			3,349
	Real estate chargeoffs:
	Commercial real estate		(256	)		(2,280	)		—
	Multifamily		(3,157	)		—			—
	Land		(1,014	)		(2,486	)		—
	Total real estate chargeoffs		(4,427	)		(4,766	)		—
	Valuation allowance at end of year	$	2,017		$	5,339		$	6,037

Deposits_Tables

Deposits (Tables)	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Scheduled Maturities of Certificates of Deposits	'
	Scheduled maturities of certificates of deposit accounts (CDs) are as follows:
		At December 31, 2013					At December 31, 2012
	($ in thousands)	Amount		Wtd-Avg			Amount		Wtd-Avg
				Stated Rate					Stated Rate
	Within one year	$	307,122		1.97	%	$	519,236		2.92	%
	Over one to two years		167,323		1.92			181,698		2.79
	Over two to three years		170,956		1.92			89,049		2.74
	Over three to four years		106,700		2.5			60,119		3.02
	Over four years		129,678		2.06			86,776		2.93
		$	881,779		2.03	%	$	936,878		2.89	%
Interest Expense on Deposit Accounts	'
	Interest expense on deposit accounts is as follows:
		For the Year Ended December 31,
	($ in thousands)	2013		2012			2011
	Interest checking accounts	$	65	$	65		$	79
	Savings accounts		29		34			58
	Money market accounts		1,530		2,142			3,669
	Certificates of deposit accounts		23,806		33,590			43,776
		$	25,430	$	35,831		$	47,582

FHLB_Advances_and_Lines_of_Cre1

FHLB Advances and Lines of Credit (Tables)	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Summary of Certain Information Regarding INB Borrowings	'
	The following is a summary of certain information regarding INB’s borrowings in the aggregate:
		At or For the Year Ended December 31,
	($ in thousands)	2013			2012			2011
	Balance at year end	$	—		$	—		$	17,500
	Maximum amount outstanding at any month end during the year	$	—		$	13,500		$	25,500
	Average outstanding balance for the year	$	295		$	9,087		$	21,574
	Weighted-average interest rate paid for the year		0.38	%		4.27	%		4.1	%
	Weighted-average interest rate at year end		—			—			4.1	%

Subordinated_Debentures_Capita1

Subordinated Debentures - Capital Securities (Tables)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Summary of Capital Securities Outstanding	'
	Capital Securities (commonly referred to as trust preferred securities) outstanding are summarized as follows:
		At December 31, 2013							At December 31, 2012
	($ in thousands)	Principal		Accrued		Interest			Principal		Accrued		Interest
				Interest		Rate					Interest		Rate
				Payable							Payable
	Capital Securities II - debentures due September 17, 2033	$	15,464	$	275		3.19	%	$	15,464	$	1,661		3.26	%
	Capital Securities III - debentures due March 17, 2034		15,464		261		3.03	%		15,464		1,577		3.1	%
	Capital Securities IV - debentures due September 20, 2034		15,464		223		2.65	%		15,464		1,370		2.71	%
	Capital Securities V - debentures due December 15, 2036		10,310		109		1.89	%		10,310		1,620		1.96	%
		$	56,702	$	868				$	56,702	$	6,228

Common_Stock_Warrant_Options_a1

Common Stock Warrant, Options and Restricted Common Stock (Tables)	12 Months Ended
	Dec. 31, 2013
Text Block [Abstract]	'
Summary of Selected Information Regarding Option Awards Made Under Plans	'
	A summary of selected information regarding option awards made under the Plans for the three-year period ended December 31, 2013 follows. There were no option awards made in 2013 or 2012:
	($ in thousands, except per option amounts)		2011
			Option Award
	Date of award			12/8/11
	Total options awarded			44,100
	Exercise price of option		$	2.55
	Estimated fair value per option (1)		$	1.67
	Total estimated fair value of award		$	73,647
	Assumptions used in Black-Scholes Model:
	Expected dividend yield (2)			0	%
	Expected stock volatility (3)			75	%
	Risk-free interest rate (4)			1.13	%
	Expected term in years (5)			6
	-1	Fair value was estimated at the grant date of the award based on the Black-Scholes option-pricing model using the assumptions noted in the table above. The assumptions are subjective in nature, involve uncertainties and therefore, cannot be determined with precision. The Black-Scholes option pricing model also contains certain inherent limitations when applied to options which are not immediately exercisable and are not traded on public markets.
	-2	No dividends were assumed to be declared and paid for shares underlying the option grants.
	-3	Expected stock volatility is estimated based on an assessment of historical volatility of IBC’s common stock.
	-4	Risk-free interest rate was derived from a U.S. Treasury security having a similar expected life as the option as of the grant date.
	-5	Expected term (average life) was calculated using the “simplified method” as prescribed by the SEC guidance.
Summary of the Activity in IBC's Outstanding Common Stock Warrant and Options	'
	A summary of the activity in IBC’s outstanding common stock warrant and options and related information follows:
	($ in thousands, except per share amounts)		Exercise Price Per Warrant/Option																					Wtd-Avg.
																								Exercise
			$5.42 (1)			$17.10			$7.50			$4.02			$3.00			$2.55			Total			Price
	Outstanding at December 31, 2010			691,882			118,140			122,290			71,710			41,400			—			1,045,422		$	6.79
	Forfeited/expired (2)			—			(300	)		(900	)		(1,200	)		(1,500	)		—			(3,900	)	$	5.44
	Options granted			—			—			—			—			—			44,100			44,100		$	2.55
	Outstanding at December 31, 2011			691,882			117,840			121,390			70,510			39,900			44,100			1,085,622		$	6.62
	Forfeited/expired (2)			—			(1,200	)		(1,200	)		(1,600	)		(1,600	)		(1,800	)		(7,400	)	$	6.13
	Exercised			—			—			—			—			(100	)		—			(100	)	$	3
	Outstanding at December 31, 2012			691,882			116,640			120,190			68,910			38,200			42,300			1,078,122		$	6.63
	Forfeited/expired (2)			—			(6,000	)		(6,200	)		(1,610	)		(2,100	)		(3,500	)		(19,410	)	$	8.8
	Options exercised			—			—			—			(9,900	)		(3,700	)		(3,667	)		(17,267	)	$	3.49
	Outstanding at December 31, 2013			691,882			110,640			113,990			57,400			32,400			35,133			1,041,445		$	6.64
	Expiration date			12/23/18			12/13/17			12/11/18			12/10/19			12/9/20			12/8/21
	Vested and exercisable (3)			100	%		100	%		100	%		100	%		100	%		67	%		99	%
	Wtd-avg contractual remaining term (in years)			5			4			4.9			5.9			6.9			7.9			5.1
	Intrinsic value at December 31, 2013 (4)		$	1,446			—		$	1		$	201		$	146		$	174		$	1,968
	-1	This warrant is held by the U.S. Treasury as described in note 10 to the financial statements.
	-2	Represent options forfeited or expired unexercised.
	-3	The $2.55 options further vest and become 100% exercisable on December 8, 2014. Full vesting may occur earlier upon the occurrence of certain events as defined in the option agreement.
	-4	Intrinsic value was calculated using the closing price of the common stock on December 31, 2013 of $7.51.
Summary of Selected Information Regarding Restricted Common Stock Awards Made Under Plans	'
	A summary of selected information regarding restricted common stock awards made under the Plans for the three-year period ended December 31, 2013 follows:
	($ in thousands, except per share amounts)		Stock Grant			Stock			Stock
						Grant			Grant
	Grant date of award			12/12/13			1/24/13			1/19/12
	Total restricted shares of stock awarded (1)			135,500			330,700			465,400
	Estimated fair value per share awarded (2)		$	7.21		$	4.5		$	2.9
	Total estimated fair value of award		$	977		$	1,488		$	1,350
	Awards scheduled to vest as follows:
	Jan-13			—			—			256,800
	Jan-14			75,417			49,566			133,455
	Jan-15			44,917			170,888			75,145
	Jan-16			15,166			110,246			—
				135,500			330,700			465,400
	-1	The December 2013 awards were made to five executive officers vesting in five installments over a three-year period. These awards replaced certain awards that were forfeited during 2013 in connection with the requirements of TARP.
	The January 2013 awards were made as follows: a total of 182,000 shares to five executive officers (vesting in two installments, with two thirds vesting on the second anniversary of the grant and the remaining one third on the third anniversary of the grant); a total of 80,000 shares to eight non-employee directors and 68,700 shares to other officers and employees (vesting in three equal installments, with one third vesting on each of the first three anniversary dates of the grant).
	The January 2012 awards were made as follows: a total of 175,000 shares to five executive officers (vesting in two installments, with two thirds vesting on the second anniversary of the grant and the remaining one third on the third anniversary of the grant); a total of 240,000 shares to six non-employee directors (vesting 100% on the first anniversary of the grant); and a total of 50,400 shares to other officers and employees (vesting in three equal installments, with one third on each of the first three anniversary dates of the grant).
	-2	Fair value of each award was estimated as of the grant date based on the closing market price of the common stock on the grant date.
Summary of Activity in IBCs Restricted Class A Common Stock	'
	A summary of activity in outstanding restricted common stock and related information follows:
			Price Per Share
			$2.35			$2.90			$4.50			$7.21			Total
	Outstanding at December 31, 2010			319,300			—			—			—			319,300
	Shares forfeited			(1,200	)		—			—			—			(1,200	)
	Outstanding at December 31, 2011			318,100			—			—			—			318,100
	Shares granted			—			465,400			—			—			465,400
	Shares forfeited			(600	)		(600	)		—			—			(1,200	)
	Outstanding at December 31, 2012			317,500			464,800			—			—			782,300
	Shares vested and no longer restricted			(264,150	)		(256,600	)		—			—			(520,750	)
	Shares granted			—			—			330,700			135,500			466,200
	Shares forfeited			(53,350	)		(49,883	)		(51,200	)		—			(154,433	)
	Outstanding at December 31, 2013 (1) (2)			—			158,317			279,500			135,500			573,317
	-1	All outstanding shares of restricted common stock at December 31, 2013 were unvested and subject to forfeiture.
	Shares issued at $2.90 will vest as follows: 101,034 on January 19, 2014 and 57,283 on January 19, 2015.
	Shares issued at $4.50 will vest as follows: 47,667 on January 24, 2014, 138,667 on January 24, 2015 and 93,166 on January 24, 2016.
	Shares issued at $7.21 will vest as follows: 46,250 on January 2, 2014; 29,167 on January 19, 2014; 14,584 on January 19, 2015; 30,333 on January 24, 2015; and 15,166 on January 24, 2016.
	-2	Vesting is subject to the grantee’s continued employment with us or, in the case of non-employee directors, the grantee’s continued service as our director on the vesting dates. All of the awards are subject to accelerated vesting upon the death or disability of the grantee or upon a change in control of IBC, as defined in the restricted stock agreements. The record holder of IBC’s restricted shares of common stock possesses all the rights of a holder of our common stock, including the right to receive dividends on and to vote the restricted shares. The restricted shares may not be sold, transferred, pledged, assigned, encumbered, or otherwise alienated or hypothecated until they become fully vested and transferable in accordance with the agreements.

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Allocation of Federal, State and Local Income Tax Expense between Current and Deferred Portions	'
	Allocation of our federal, state and local income tax expense between current and deferred portions is as follows:
	($ in thousands)	Current			Deferred			Total
	Year Ended December 31, 2013:
	Federal	$	420		$	9,130		$	9,550
	State and Local		339			1,766			2,105
		$	759		$	10,896		$	11,655
	Year Ended December 31, 2012:
	Federal	$	370		$	7,751		$	8,121
	State and Local		335			1,851			2,186
		$	705		$	9,602		$	10,307
	Year Ended December 31, 2011:
	Federal	$	958		$	6,670		$	7,628
	State and Local		311			1,573			1,884
		$	1,269		$	8,243		$	9,512
Components of Deferred Tax Expense	'
	The components of the deferred tax expense are as follows:
		For the Year Ended December 31,
	($ in thousands)	2013			2012			2011
	NOL and AMT credit carryforwards	$	7,353		$	8,084		$	8,138
	Allowances for loan losses and real estate losses		1,597			1,315			484
	Capitalized real estate expenses and nonaccrual interest		36			1,011			(232	)
	Impairment writedowns on investment securities		1,857			(282	)		(86	)
	Deferred compensation and benefits		285			(355	)		(48	)
	Depreciation		(234	)		(166	)		(16	)
	Deferred income		2			(5	)		3
		$	10,896		$	9,602		$	8,243
Tax Effects of Temporary Differences in Deferred Tax Asset	'
	The tax effects of the temporary differences that give rise to the deferred tax asset are as follows:
		At December 31,
	($ in thousands)	2013			2012
	NOL and AMT credit carryforwards	$	3,061		$	10,414
	Allowances for loan losses and real estate losses		12,814			14,411
	Capitalized real estate expenses and nonaccrual interest		1,152			1,188
	Impairment writedowns on investment securities		—			1,857
	Unrealized losses on securities available for sale		24			—
	Deferred compensation and benefits		852			1,137
	Depreciation		454			220
	Deferred income		5			7
	Total deferred tax asset	$	18,362		$	29,234
Reconciliation between Statutory Federal Income Tax Rate and Our Effective Income Tax Rate	'
	The reconciliation between the statutory federal income tax rate and our effective income tax rate is as follows:
		For the Year Ended December 31,
		2013			2012			2011
	Federal statutory income tax rate		35	%		35	%		35	%
	Increase resulting from:
	State and local income tax rate, net of federal benefit		7.8			9.4			9.3
	All other		1.8			1.4			1.5
	Effective Income Tax Rate		44.6	%		45.8	%		45.8	%

Earnings_Per_Common_Share_Tabl

Earnings Per Common Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Summary of Basic and Diluted Earnings Per Common Share	'
	Net earnings available to common stockholders and the weighted-average number of shares used for basic and diluted earnings per common share computations are summarized in the table that follows:
			For the Year Ended December 31,
			2013		2012		2011
	Basic Earnings Per Common Share:
	Net earnings available to common stockholders		$	13,437,000	$	10,421,000	$	9,516,000
	Weighted-Average number of common shares outstanding			21,894,030		21,566,009		21,126,187
	Basic Earnings Per Common Share		$	0.61	$	0.48	$	0.45
	Diluted Earnings Per Common Share:
	Net earnings available to common stockholders		$	13,437,000	$	10,421,000	$	9,516,000
	Weighted-Average number of common shares outstanding:
	Common shares outstanding			21,894,030		21,566,009		21,126,187
	Potential dilutive shares resulting from exercise of warrants /options (1)			99,596		2,187		—
	Total average number of common shares outstanding used for dilution			21,993,626		21,568,196		21,126,187
	Diluted Earnings Per Common Share		$	0.61	$	0.48	$	0.45
	-1	All outstanding options/warrants to purchase shares of our common stock were considered for the Diluted EPS computations and only those that were dilutive (as determined by using the treasury stock method prescribed by GAAP) were included in the diluted earnings per share computations above. In 2013, 2012 and 2011, 224,630, 997,622 and 1,085,622 of options/warrants to purchase common stock, respectively, were not dilutive because the exercise price per share of each option/warrant was above the average market price of our common stock during these periods.

OffBalance_Sheet_Financial_Ins1

Off-Balance Sheet Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2013
Investments All Other Investments [Abstract]	'
Summary of Contractual Amounts of Off-Balance Sheet Financial Instruments	'
	The contractual amounts of off-balance sheet financial instruments are as follows:
		At December 31,
	($ in thousands)	2013		2012
	Commitments to extend credit	$	19,386	$	19,154
	Unused lines of credit		877		854
		$	20,263	$	20,008

Regulatory_Capital_and_Regulat1

Regulatory Capital and Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2013
Banking And Thrift [Abstract]	'
Summary of Regulatory Capital and Related Ratios	'
	Information regarding our regulatory capital and related ratios is summarized as follows:
			INB						IBC Consolidated
			At December 31,						At December 31,
	($ in thousands)		2013			2012			2013			2012
	Tier 1 capital (1)		$	240,918		$	244,081		$	245,191		$	249,465
	Tier 2 capital			15,479			15,566			15,517			15,620
	Total risk-based capital (2)		$	256,397		$	259,647		$	260,708		$	265,085
	Net risk-weighted assets for regulatory purposes		$	1,225,936		$	1,232,670		$	1,228,994		$	1,238,024
	Average assets for regulatory purposes		$	1,581,713		$	1,690,329		$	1,586,416		$	1,696,410
	Total capital to risk-weighted assets			20.91	%		21.06	%		21.21	%		21.41	%
	Tier 1 capital to risk-weighted assets			19.65	%		19.8	%		19.95	%		20.15	%
	Tier 1 capital to average assets			15.23	%		14.44	%		15.46	%		14.71	%
	-1	IBC’s consolidated Tier 1 capital at both dates included $55 million of IBC’s outstanding qualifying trust preferred securities.
Capital Adequacy	'
	The table that follows presents information regarding our actual capital and minimum capital requirements.
			Actual Capital						Minimum						Minimum					Minimum
									Under Prompt						To Be “Well Capitalized”					Under Agreement
									Corrective						Under Prompt Corrective					With OCC
									Action Provisions						Action Provisions
	($ in thousands)		Amount			Ratio			Amount			Ratio			Amount		Ratio			Amount		Ratio
	IBC Consolidated at December 31, 2013:
	Total capital to risk-weighted assets (1)		$	260,708			21.21	%	$	98,320			8	%		NA		NA			NA		NA
	Tier 1 capital to risk-weighted assets (1)		$	245,191			19.95	%	$	49,160			4	%		NA		NA			NA		NA
	Tier 1 capital to average assets (1)		$	245,191			15.46	%	$	63,457			4	%		NA		NA			NA		NA
	IBC Consolidated at December 31, 2012:
	Total capital to risk-weighted assets		$	265,085			21.41	%	$	99,042			8	%		NA		NA			NA		NA
	Tier 1 capital to risk-weighted assets		$	249,465			20.15	%	$	49,521			4	%		NA		NA			NA		NA
	Tier 1 capital to average assets		$	249,465			14.71	%	$	67,856			4	%		NA		NA			NA		NA
	INB at December 31, 2013:
	Total capital to risk-weighted assets		$	256,397			20.91	%	$	98,075			8	%	$	122,594		10	%		NA		NA
	Tier 1 capital to risk-weighted assets		$	240,918			19.65	%	$	49,037			4	%	$	73,556		6	%		NA		NA
	Tier 1 capital to average assets		$	240,918			15.23	%	$	63,269			4	%	$	79,086		5	%		NA		NA
	INB at December 31, 2012:
	Total capital to risk-weighted assets		$	259,647			21.06	%	$	98,614			8	%	$	123,267		10	%	$	147,920		12	%
	Tier 1 capital to risk-weighted assets		$	244,081			19.8	%	$	49,307			4	%	$	73,960		6	%	$	123,267		10	%
	Tier 1 capital to average assets		$	244,081			14.44	%	$	67,613			4	%	$	84,516		5	%	$	152,130		9	%
	-1	Assuming IBC had excluded all of its eligible outstanding trust preferred securities (which totaled $55 million) from its Tier 1 capital and included the entire amount in its Tier 2 capital, consolidated proforma capital ratios at December 31, 2013 would have been 21.21%, 15.48% and 11.99%, respectively.
Additional Information Regarding Capital Adequacy	'
	The table that follows presents additional information regarding our capital adequacy at December 31, 2013.
			INB Regulatory Capital									Consolidated Regulatory Capital
	($ in thousands)		Actual			Required (1)			Excess			Actual			Required		Excess
	Total capital to risk-weighted assets		$	256,397		$	122,594		$	133,803		$	260,708		$	98,320	$	162,388
	Tier 1 capital to risk-weighted assets		$	240,918		$	73,556		$	167,362		$	245,191		$	49,160	$	196,031
	Tier 1 capital to average assets		$	240,918		$	79,086		$	161,832		$	245,191		$	63,457	$	181,734
	-1	Minimum amount required to be considered “Well-Capitalized.”

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Assets Measured at Fair Value on a Nonrecurring Basis	'
	The following tables provide information regarding our assets measured at fair value on a nonrecurring basis.
			Outstanding Carrying Value
			At December 31,
			2013			2012
	($ in thousands)		Level 3			Level 3
	Impaired loans (1) :
	Commercial real estate		$	52,407		$	50,795
	Multifamily			3,128			12,577
	Land			1,625			2,601
	Total impaired loans			57,160			65,973
	Impaired securities (2)			—			3,721
	Foreclosed real estate			10,669			15,923
			Accumulated Losses on
			Outstanding Balance						Total Losses (Gains) (3)
			At December 31,						For the Year Ended December 31,
	($ in thousands)		2013			2012			2013			2012			2011
	Impaired loans:
	Commercial real estate		$	10,294		$	9,979		$	2,053		$	1,038		$	4,936
	Multifamily			598			3,092			(966	)		(364	)		4,190
	Land			500			521			(21	)		(488	)		1,009
	Total impaired loans			11,392			13,592			1,066			186			10,135
	Impaired securities			—			4,233			(517	)		582			201
	Foreclosed real estate			2,017			5,339			142			4,161			3,161
	-1	Outstanding carrying value excludes a specific valuation allowance included in the overall allowance for loan losses. See notes 3 and 4 to the financial statements.
	-2	Comprised at December 31, 2012 of certain held-to maturity investments in trust preferred securities considered other than temporarily impaired. See note 2 to the financial statements.
	-3	Represents total losses or (gains) recognized on all assets measured at fair value on a nonrecurring basis during the period indicated. The losses or (gains) for impaired loans represent the change (before net chargeoffs) during the period in the corresponding specific valuation allowance, while the losses (gains) for foreclosed real estate represent writedowns in carrying values subsequent to foreclosure (recorded as provisions for real estate losses) adjusted for any recoveries of prior write downs and (gains) or losses from the transfer/sale of properties during the period. The (gains) losses on securities represent the total of other than temporary impairment charges and net gains from sales, which are recorded as components of noninterest income. See note 2 to the financial statements in this report.
Change in Assets Measured at Fair Value on a Nonrecurring Basis	'
	The following table presents information regarding the change in assets measured at fair value on a nonrecurring basis for the three-year period ended December 31, 2013.
			Impaired			Impaired			Foreclosed
	($ in thousands)		Securities			Loans			Real Estate
	Balance at December 31, 2010		$	4,580		$	56,555		$	27,064
	Net new impaired loans			—			41,768			—
	Principal repayments/sales			—			(18,198	)		—
	Chargeoffs			—			(9,481	)		—
	Ttransferred to foreclosed real estate			—			(4,375	)		4,375
	Other than temporary impairment writedowns			(201	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(3,349	)
	Gain on sales/transfers from loans			—			—			188
	All other			(1	)		—			—
	Balance at December 31, 2011		$	4,378		$	66,269		$	28,278
	Net new impaired loans			—			19,875			—
	Principal repayments/sales			(75	)		(12,330	)		(12,883	)
	Chargeoffs			—			(3,152	)		—
	Ttransferred to foreclosed real estate			—			(4,689	)		4,689
	Other than temporary impairment writedowns			(582	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(4,068	)
	Loss on sales			—			—			(93	)
	Balance at December 31, 2012		$	3,721		$	65,973		$	15,923
	Net new impaired loans			—			16,122			—
	Principal repayments/sales			(4,238	)		(19,957	)		(8,152	)
	Chargeoffs			—			(1,938	)		—
	Ttransferred to foreclosed real estate			—			(3,040	)		3,040
	Other than temporary impairment writedowns			(964	)		—			—
	Writedowns of carrying value subsequent to foreclosure			—			—			(1,105	)
	Gain on sales			1,481			—			963
	Balance at December 31, 2013		$	—		$	57,160		$	10,669
Carrying and Estimated Fair Values of Financial Instruments	'
	The carrying and estimated fair values of our financial instruments are as follows:
			At December 31, 2013						At December 31, 2012
	($ in thousands)		Carrying			Fair			Carrying			Fair
			Value			Value			Value			Value
	Financial Assets:
	Cash and cash equivalents (1)		$	24,700		$	24,700		$	60,395		$	60,395
	Time deposits with banks (1)			5,370			5,370			5,170			5,170
	Securities available for sale, net (1)			965			965			1,000			1,000
	Securities held to maturity, net (2)			383,937			378,507			443,777			442,166
	FRB and FHLB stock (3)			8,244			8,244			8,151			8,151
	Loans receivable, net (3)			1,099,689			1,100,858			1,079,363			1,102,333
	Accrued interest receivable (3)			4,861			4,861			5,191			5,191
	Loan fees receivable (3)			2,298			1,808			3,108			2,547
	Total Financial Assets		$	1,530,064		$	1,525,313		$	1,606,155		$	1,626,953
	Financial Liabilities:
	Deposits (3)		$	1,282,232		$	1,294,690		$	1,362,619		$	1,389,629
	Borrowed funds plus accrued interest payable (3)			57,570			57,260			62,930			62,448
	Accrued interest payable on deposits (3)			1,508			1,508			2,379			2,379
	Commitments to lend (3)			408			408			386			386
	Total Financial Liabilities		$	1,341,718		$	1,353,866		$	1,428,314		$	1,454,842
	Net Financial Assets		$	188,346		$	171,447		$	177,841		$	172,111
	-1	We consider these fair value measurements to be Level 1.
	-2	We consider these fair value measurements to be Level 2, except for our corporate security investments held to maturity, which are considered to be Level 3.
	-3	We consider these fair value measurements to be Level 3.

Holding_Company_Financial_Info1

Holding Company Financial Information (Tables)	12 Months Ended
	Dec. 31, 2013
Organization Consolidation And Presentation Of Financial Statements [Abstract]	'
Condensed Balance Sheets	'
	The following IBC (parent company only) condensed financial information should be read in conjunction with the other notes to the consolidated financial statements in this report.
	Condensed Balance Sheets
			At December 31,
	($ in thousands)		2013			2012
	ASSETS
	Cash and due from banks		$	319		$	46
	Short-term investments			2,241			8,070
	Total cash and cash equivalents			2,560			8,116
	Loans receivable (net of allowance for loan losses of $50)			1,777			2,753
	Investment in consolidated subsidiaries			240,918			254,815
	Investment in unconsolidated subsidiaries - Intervest Statutory Trusts			1,702			1,702
	Deferred income tax asset			6,800			5,748
	Deferred debenture offering costs, net of amortization			742			779
	All other assets			220			388
	Total assets		$	254,719		$	274,301
	LIABILITIES
	Debentures payable - capital securities		$	56,702		$	56,702
	Accrued interest payable on debentures			868			6,228
	All other liabilities			158			424
	Total liabilities			57,728			63,354
	STOCKHOLDERS’ EQUITY
	Preferred equity, net of preferred stock discount			—			24,624
	Common equity			196,991			186,323
	Total stockholders’ equity			196,991			210,947
	Total liabilities and stockholders’ equity		$	254,719		$	274,301
Condensed Statements of Earnings	'
	Condensed Statements of Earnings
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	Interest income		$	129		$	264		$	475
	Interest expense			1,679			1,848			2,072
	Net interest expense			(1,550	)		(1,584	)		(1,597	)
	Provision for loan losses			—			—			290
	Noninterest income			5			5			8
	Noninterest expenses			745			773			816
	Loss before credit for income taxes			(2,290	)		(2,352	)		(2,695	)
	Credit for income taxes			1,052			1,080			1,237
	Net loss before earnings of subsidiary			(1,238	)		(1,272	)		(1,458	)
	Equity in undistributed earnings of Intervest National Bank			15,732			13,494			12,704
	Consolidated net earnings			14,494			12,222			11,246
	Preferred stock dividend requirements and discount amortization (1)			1,057			1,801			1,730
	Consolidated net earnings available to common stockholders		$	13,437		$	10,421		$	9,516
	-1	Represents dividend requirements on preferred stock and amortization of related preferred stock discount.
Condensed Statements of Cash Flows	'
	Condensed Statements of Cash Flows
			For the Year Ended December 31,
	($ in thousands)		2013			2012			2011
	OPERATING ACTIVITIES
	Consolidated net earnings		$	14,494		$	12,222		$	11,246
	Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:
	Equity in earnings of subsidiary			(15,732	)		(13,494	)		(12,704	)
	Cash dividends from subsidiary			31,000			—			—
	(Decrease) increase in accrued interest payable on debentures			(5,360	)		1,867			2,099
	All other, net change			(1,460	)		(1,116	)		(926	)
	Net cash provided by (used in) operating activities			22,942			(521	)		(285	)
	INVESTING ACTIVITIES
	Return of capital from subsidiary			—			—			229
	Net decrease in loans receivable			981			45			3,884
	Purchase of premises and equipment			(154	)		—			—
	Net cash provided by investing activities			827			45			4,113
	FINANCING ACTIVITIES
	Net (decrease) increase in mortgage escrow funds payable			(84	)		44			(217	)
	Redemption of preferred stock			(24,813	)		—			—
	Cash dividends paid to preferred stockholders			(5,068	)		—			—
	Proceeds from issuance of common stock upon exercise of options			61			—			—
	Excess tax benefit from exercise of options and vesting of restricted stock			579			—			—
	Net cash (used in) provided by financing activities			(29,325	)		44			(217	)
	Net (decrease) increase in cash and cash equivalents			(5,556	)		(432	)		3,611
	Cash and cash equivalents at beginning of year			8,116			8,548			4,937
	Cash and cash equivalents at end of year		$	2,560		$	8,116		$	8,548
	SUPPLEMENTAL DISCLOSURES
	Cash paid for interest		$	7,002		$	—		$	—
	Cash paid for (received from refunds of) income taxes, net			—			—			(43	)
	Transfer of loans from subsidiary			—			—			7,437
	Transfer of all other net assets from subsidiary			—			—			1,030
	Subsidiary’s compensation expense related to equity awards			823			1,194			326
	Preferred dividend requirements and amortization of preferred stock discount			1,057			1,801			1,730

Selected_Quarterly_Financial_D1

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Interim Results of Operations and Other Period-End Selected Information by Quarter	'
	The following is a summary of our unaudited interim results of operations and other period-end selected information by quarter for the years ended December 31, 2013 and 2012.
		2013
	($ in thousands, except per share amounts)	Q1			Q2			Q3		Q4
	Interest and dividend income	$	16,249		$	15,623		$	15,624	$	16,120
	Interest expense		7,245			7,048			6,794		6,023
	Net interest and dividend income		9,004			8,575			8,830		10,097
	(Credit) provision for loan losses		(1,000	)		(750	)		250		950
	Net interest and dividend income after (credit) provision for loan losses		10,004			9,325			8,580		9,147
	Noninterest income		743			702			901		2,600
	Noninterest expenses:
	Provision for real estate losses		629			76			250		150
	Real estate expenses (income), net		(986	)		(346	)		212		284
	Operating expenses		4,138			3,954			3,862		3,630
	Earnings before provision for income taxes		6,966			6,343			5,157		7,683
	Provision for income taxes		3,075			2,804			2,300		3,476
	Net earnings		3,891			3,539			2,857		4,207
	Preferred dividend requirements and discount amortization		462			326			269		—
	Net earnings available to common stockholders	$	3,429		$	3,213		$	2,588	$	4,207
	Basic earnings per common share	$	0.16		$	0.14		$	0.12	$	0.19
	Diluted earnings per common share		0.16			0.14			0.12		0.19
	Cash dividends paid per common share		—			—			—		—
	Total assets	$	1,627,787		$	1,596,639		$	1,584,239	$	1,567,796
	Total cash, short-term investments and security investments		507,665			512,573			461,197		423,216
	Total loans, net of unearned fees		1,081,482			1,056,191			1,100,277		1,127,522
	Total deposits		1,318,215			1,293,175			1,298,403		1,282,232
	Total borrowed funds and related accrued interest payable		63,373			56,760			57,165		57,570
	Total stockholders’ equity		215,265			211,775			192,288		196,991
		2012
	($ in thousands, except per share amounts)	Q1			Q2			Q3		Q4
	Interest and dividend income	$	20,698		$	19,706		$	19,082	$	17,798
	Interest expense		10,740			10,001			9,223		8,103
	Net interest and dividend income		9,958			9,705			9,859		9,695
	Provision for loan losses		—			—			—		—
	Net interest and dividend income after provision for loan losses		9,958			9,705			9,859		9,695
	Noninterest income		1,125			1,406			1,187		2,476
	Noninterest expenses:
	Provision for real estate losses		511			1,397			1,025		1,135
	Real estate expenses, net		460			479			883		324
	Operating expenses		4,164			4,149			4,160		4,195
	Earnings before provision for income taxes		5,948			5,086			4,978		6,517
	Provision for income taxes		2,694			2,326			2,300		2,987
	Net earnings		3,254			2,760			2,678		3,530
	Preferred dividend requirements and discount amortization		444			448			453		456
	Net earnings available to common stockholders	$	2,810		$	2,312		$	2,225	$	3,074
	Basic earnings per common share	$	0.13		$	0.11		$	0.1	$	0.14
	Diluted earnings per common share		0.13			0.11			0.1		0.14
	Cash dividends paid per common share		—			—			—		—
	Total assets	$	1,909,052		$	1,862,110		$	1,751,880	$	1,665,792
	Total cash, short-term investments and security investments		691,205			667,509			546,397		518,493
	Total loans, net of unearned fees		1,155,437			1,137,780			1,155,171		1,107,466
	Total deposits		1,599,653			1,554,615			1,432,209		1,362,619
	Total borrowed funds and related accrued interest payable		72,064			72,528			69,487		62,930
	Total stockholders’ equity		201,051			204,121			207,108		210,947

Description_of_Business_and_Su2

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Office
Business Acquisition [Line Items]	'	'	'
Percentage owns by IBC of Statutory business trusts capital stock	100.00%	'	'
Number of full-service banking offices	6	'	'
Federal funds sold for period	'1 day	'	'
Short-term investments maturities	'3 months	'	'
Non accrual loans past due period	'90 days	'	'
Risk weight of loan for regulatory capital purposes	100.00%	'	'
Compliance related to real estate loan	'loan-to-value ratios (the ratio that the original principal amount of the loan bears to the lower of the purchase price or appraised value of the property securing the loan at the time of origination) on loans originated by us typically do not exceed 80% and in practice, rarely exceed 75%	'	'
Minimum debt service coverage ratio	1.2	'	'
Period over which borrower has demonstrated satisfactory payment performance leading to TDR that is on nonaccrual status returned to an accrual status	'6 months	'	'
Maximum period of delinquencies for minimal delays	'60 days	'	'
Costs relating to offerings of debentures (approximately)	$700,000	$800,000	'
Accumulated amortization	400,000	300,000	'
Advertising costs	$23,000	$17,000	$26,000
More-likely-than-not recognition threshold (Percent) of tax position	50.00%	'	'
Clearwater [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Number of full-service banking offices	4	'	'
Clearwater Beach [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Number of full-service banking offices	1	'	'
South Pasadena [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Number of full-service banking offices	1	'	'
INB [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Percentage owned in subsidiary	100.00%	'	'
Percent INB accounts in parents consolidated assets	99.00%	'	'
IMC [Member]	'	'	'
Business Acquisition [Line Items]	'	'	'
Number of Statutory business trusts	4	'	'

Securities_Held_to_Maturity_an2

Securities Held to Maturity and Available for Sale - Carrying Value (Amortized Cost) and Estimated Fair Value of Securities Held to Maturity (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Security	Security
Schedule of Held-to-maturity Securities [Line Items]	'	'
Number of Securities	219	222
Amortized Cost	$383,937	$443,777
Gross Unrealized Gains	540	1,760
Gross Unrealized Losses	5,970	3,371
Estimated Fair Value	378,507	442,166
Wtd-Avg Yield	1.11%	1.05%
Wtd-Avg Expected Life	'3 years 3 months 18 days	'2 years
Wtd-Avg Remaining Maturity	'6 years	'7 years 1 month 6 days
U.S. Government Agencies [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Number of Securities	161	165
Amortized Cost	305,906	355,244
Gross Unrealized Gains	410	1,109
Gross Unrealized Losses	4,947	233
Estimated Fair Value	301,369	356,120
Wtd-Avg Yield	0.94%	0.87%
Wtd-Avg Expected Life	'3 years	'1 year 7 months 6 days
Wtd-Avg Remaining Maturity	'3 years 9 months 18 days	'4 years 7 months 6 days
Residential Mortgage-backed [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Number of Securities	57	48
Amortized Cost	77,500	84,279
Gross Unrealized Gains	130	651
Gross Unrealized Losses	1,017	72
Estimated Fair Value	76,613	84,858
Wtd-Avg Yield	1.79%	1.76%
Wtd-Avg Expected Life	'4 years 3 months 18 days	'3 years 3 months 18 days
Wtd-Avg Remaining Maturity	'14 years 8 months 12 days	'17 years 3 months 18 days
State and Municipal [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Number of Securities	1	1
Amortized Cost	531	533
Gross Unrealized Gains	'	'
Gross Unrealized Losses	6	3
Estimated Fair Value	525	530
Wtd-Avg Yield	1.25%	1.25%
Wtd-Avg Expected Life	'3 years 2 months 12 days	'4 years 2 months 12 days
Wtd-Avg Remaining Maturity	'3 years 3 months 18 days	'4 years 3 months 18 days
Corporate [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Number of Securities	'	8
Amortized Cost	'	3,721
Gross Unrealized Gains	'	'
Gross Unrealized Losses	'	3,063
Estimated Fair Value	'	$658
Wtd-Avg Yield	'	2.11%
Wtd-Avg Expected Life	'	'20 years 3 months 18 days
Wtd-Avg Remaining Maturity	'	'20 years 10 months 24 days

Securities_Held_to_Maturity_an3

Securities Held to Maturity and Available for Sale - Carrying Value (Amortized Cost) and Estimated Fair Value of Securities Held to Maturity (Parenthetical) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	$383,937,000	$443,777,000
Other than temporary impairment charges	'	4,200,000
Additional OTTI charges	1,000,000	'
Government National Mortgage Association [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	13,600,000	18,700,000
Federal National Mortgage Association [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	45,600,000	40,000,000
Federal Home Loan Mortgage Corporation Participation Certificates [Member]	'	'
Schedule of Held-to-maturity Securities [Line Items]	'	'
Amortized Cost	$18,300,000	$25,600,000

Securities_Held_to_Maturity_an4

Securities Held to Maturity and Available for Sale - Continuous Unrealized Loss Position (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Security	Security
Long Term Debt Maturity [Line Items]	'	'
Number of Securities	172	76
Less Than Twelve Months, Estimated Fair Value	$283,317	$154,376
Less Than Twelve Months, Gross Unrealized Losses	5,784	308
Twelve Months or Longer, Estimated Fair Value	10,628	658
Twelve Months or Longer, Gross Unrealized Losses	186	3,063
Total Estimated Fair Value	293,945	155,034
Total Gross Unrealized Losses	5,970	3,371
U.S. Government Agencies [Member]	'	'
Long Term Debt Maturity [Line Items]	'	'
Number of Securities	130	53
Less Than Twelve Months, Estimated Fair Value	233,930	129,365
Less Than Twelve Months, Gross Unrealized Losses	4,791	233
Twelve Months or Longer, Estimated Fair Value	7,344	'
Twelve Months or Longer, Gross Unrealized Losses	156	'
Total Estimated Fair Value	241,274	129,365
Total Gross Unrealized Losses	4,947	233
Residential Mortgage-backed [Member]	'	'
Long Term Debt Maturity [Line Items]	'	'
Number of Securities	41	14
Less Than Twelve Months, Estimated Fair Value	48,862	24,481
Less Than Twelve Months, Gross Unrealized Losses	987	72
Twelve Months or Longer, Estimated Fair Value	3,284	'
Twelve Months or Longer, Gross Unrealized Losses	30	'
Total Estimated Fair Value	52,146	24,481
Total Gross Unrealized Losses	1,017	72
State and Municipal [Member]	'	'
Long Term Debt Maturity [Line Items]	'	'
Number of Securities	1	1
Less Than Twelve Months, Estimated Fair Value	525	530
Less Than Twelve Months, Gross Unrealized Losses	6	3
Twelve Months or Longer, Estimated Fair Value	'	'
Twelve Months or Longer, Gross Unrealized Losses	'	'
Total Estimated Fair Value	525	530
Total Gross Unrealized Losses	6	3
Corporate [Member]	'	'
Long Term Debt Maturity [Line Items]	'	'
Number of Securities	'	8
Less Than Twelve Months, Estimated Fair Value	'	'
Less Than Twelve Months, Gross Unrealized Losses	'	'
Twelve Months or Longer, Estimated Fair Value	'	658
Twelve Months or Longer, Gross Unrealized Losses	'	3,063
Total Estimated Fair Value	'	658
Total Gross Unrealized Losses	'	$3,063

Securities_Held_to_Maturity_an5

Securities Held to Maturity and Available for Sale - Summary of Carrying Value (Amortized Cost) and Fair Value of Securities Held to Maturity (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Investments Debt And Equity Securities [Abstract]	'	'
Due in one year or less, Amortized Cost	$12,329	'
Due in one year or less, Estimated Fair Value	12,394	'
Due in one year or less, Wtd-Avg Yield	1.27%	'
Due after one year through five years, Amortized Cost	262,878	'
Due after one year through five years, Estimated Fair Value	259,611	'
Due after one year through five years, Wtd-Avg Yield	0.90%	'
Due after five years through ten years, Amortized Cost	56,507	'
Due after five years through ten years, Estimated Fair Value	54,962	'
Due after five years through ten years, Wtd-Avg Yield	1.38%	'
Due after ten years, Amortized Cost	52,223	'
Due after ten years, Estimated Fair Value	51,540	'
Due after ten years, Wtd-Avg Yield	1.87%	'
Securities held to maturity, Total Amortized Cost	383,937	'
Estimated Fair Value	$378,507	$442,166
Securities held to maturity, Wtd-Avg Yield	1.11%	1.05%

Securities_Held_to_Maturity_an6

Securities Held to Maturity and Available for Sale - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Investments Debt And Equity Securities [Abstract]	'	'
Credit losses	$5,200,000	'
Securities available for sale	$965,000	$1,000,000
Shares owned in an intermediate bond fund	91,700	90,000

Securities_Held_to_Maturity_an7

Securities Held to Maturity and Available for Sale - Credit Losses Recognized on Securities (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Investments Debt And Equity Securities [Abstract]	'	'	'
Balance at beginning of period	$4,233	$3,651	$3,450
Additional credit losses on debt securities for which OTTI was previously recognized	964	582	201
Balance at end of period	$5,197	$4,233	$3,651

Securities_Held_to_Maturity_an8

Securities Held to Maturity and Available for Sale - Schedule of Corporate Securities Available for Sale (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]	'	'
Cumulative OTTI Charges	$5,200	'
Net Carrying Value	965	1,000
Net Proceeds from Sale	4,050	'
Net Gain on Sale	1,481	'
Corporate [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Original Cost Basis	8,029	'
Cumulative Cash Payments Applied to Cost	-263	'
Cumulative OTTI Charges	-5,197	'
Net Carrying Value	2,569	'
Net Proceeds from Sale	4,050	'
Net Gain on Sale	$1,481	'

Loans_Receivable_Major_Classif

Loans Receivable - Major Classification of Loans Receivable (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified	SecurityLoan	SecurityLoan
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	588,000	568,000	'	'
Loans receivable, gross, Amount	$1,131,550	$1,111,063	'	'
Deferred loan fees	-4,028	-3,597	'	'
Loans receivable, net of deferred fees	1,127,522	1,107,466	'	'
Allowance for loan losses	-27,833	-28,103	-30,415	-34,840
Loans receivable, net	1,099,689	1,079,363	'	'
Loans Secured by Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	557,000	538,000	'	'
Loans receivable, gross, Amount	1,130,278	1,109,755	'	'
All Other Loans [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	31,000	30,000	'	'
Loans receivable, gross, Amount	1,272	1,308	'	'
Commercial Real Estate [Member] | Loans Secured by Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	394,000	376,000	'	'
Loans receivable, gross, Amount	838,766	852,213	'	'
Multifamily [Member] | Loans Secured by Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	138,000	142,000	'	'
Loans receivable, gross, Amount	210,270	208,699	'	'
One to Four Family [Member] | Loans Secured by Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	20,000	13,000	'	'
Loans receivable, gross, Amount	72,064	41,676	'	'
Land Loans [Member] | Loans Secured by Real Estate [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	5,000	7,000	'	'
Loans receivable, gross, Amount	9,178	7,167	'	'
Business Loans [Member] | All Other Loans [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	19,000	18,000	'	'
Loans receivable, gross, Amount	1,061	949	'	'
Consumer Loans [Member] | All Other Loans [Member]	'	'	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'	'	'
Loans receivable, gross, # of Loans	12,000	12,000	'	'
Loans receivable, gross, Amount	$211	$359	'	'

Loans_Receivable_Additional_In

Loans Receivable - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
	SecurityLoan	Debt
	Debt
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
90 days past due and still accruing interest loan	$4,087,000	$10,042,000
Troubled debt restructured loans	46,613,000	56,367,000
Performing and accruing loans classified as impaired	7,800,000	'
Performing loans	1	'
Amount of TDR defaulted	3,000,000	'
TDR matured	1,900,000	'
TDR defaulted	1	0
Accruing Loans [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Number of loans, 90 days past due and still accruing	3	2
90 days past due and still accruing interest loan	4,100,000	4,400,000
Troubled debt restructured loans	13,100,000	20,100,000
Troubled debt restructured loans	13,500,000	20,100,000
Nonaccrual Loans [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total loans	35,900,000	45,900,000
Troubled debt restructured loans	35,900,000	45,900,000
Non-accrual Status [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Troubled debt restructured loans	$33,200,000	$36,300,000

Loans_Receivable_Summary_of_Im

Loans Receivable - Summary of Impaired Loans (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	SecurityLoan	SecurityLoan
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	$57,160	$65,973
Specific Valuation Allowance	6,093	5,888
Total Unpaid Principal	64,601	74,414
# of Loans	13	23
New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	8,223	21,934
Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	27,070	39,570
Virginia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	7,828	'
Georgia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	8,695	'
Connecticut [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	2,719	'
Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	1,000	1,000
South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	1,625	2,086
New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	1,383
Retail [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	28,775	21,842
Specific Valuation Allowance	3,052	1,966
Total Unpaid Principal	36,216	27,596
# of Loans	7	6
Retail [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	8,223	11,837
Retail [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	9,005	9,005
Retail [Member] | Virginia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	7,828	'
Retail [Member] | Georgia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Retail [Member] | Connecticut [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	2,719	'
Retail [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	1,000	1,000
Retail [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Retail [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	233,632	18,871
Specific Valuation Allowance	1,947	583
Total Unpaid Principal	23,632	19,621
# of Loans	3	3
Office Building [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	14,937	17,988
Office Building [Member] | Virginia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member] | Georgia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	8,695	'
Office Building [Member] | Connecticut [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Office Building [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	883
Multifamily [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	3,128	12,577
Specific Valuation Allowance	594	1,542
Total Unpaid Principal	3,128	14,225
# of Loans	2	6
Multifamily [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	3,128	12,577
Multifamily [Member] | Virginia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | Georgia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | Connecticut [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Multifamily [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	1,625	2,601
Specific Valuation Allowance	500	521
Total Unpaid Principal	1,625	2,601
# of Loans	1	3
Land [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	515
Land [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member] | Virginia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member] | Georgia [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member] | Connecticut [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Land [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	1,625	2,086
Land [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Warehouse [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	950
Specific Valuation Allowance	'	28
Total Unpaid Principal	'	950
# of Loans	'	1
Warehouse [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	950
Warehouse [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Warehouse [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Warehouse [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Warehouse [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Mixed-Use Commercial [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	9,132
Specific Valuation Allowance	'	1,248
Total Unpaid Principal	'	9,421
# of Loans	'	4
Mixed-Use Commercial [Member] | New York [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	8,632
Mixed-Use Commercial [Member] | Florida [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Mixed-Use Commercial [Member] | Ohio [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Mixed-Use Commercial [Member] | South Dakota [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	'
Mixed-Use Commercial [Member] | New Jersey [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Recorded Investment	'	$500

Loans_Receivable_Other_Informa

Loans Receivable - Other Information Related to Impaired Loans (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Nonaccrual Loans [Member]	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'
Average recorded investment in loans	$40,345	$52,199	$51,356
Total cash basis interest income recognized on nonaccrual loans	2,265	2,660	2,437
TDR Loans [Member]	'	'	'
Financing Receivable, Modifications [Line Items]	'	'	'
Average recorded investment in loans	13,918	12,289	5,417
Total interest income recognized on accruing TDR loans under modified terms	$734	$739	$299

Loans_Receivable_Age_Analysis_

Loans Receivable - Age Analysis of Loan Portfolio by Segment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	$1,131,550	$1,111,063
Current	1,124,822	1,085,524
Past Due 31-59 Days	2,641	15,497
Past Due 60-89 Days	'	'
Past Due 90 or more Days	4,087	10,042
Total Past Due	6,728	25,539
Total Classified Nonaccrual	35,903	45,898
Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	1,095,647	1,065,165
Current	1,088,919	1,045,277
Past Due 31-59 Days	2,641	15,497
Past Due 60-89 Days	'	'
Past Due 90 or more Days	4,087	4,391
Total Past Due	6,728	19,888
Total Classified Nonaccrual	'	'
Nonaccrual Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	35,903	45,898
Current	35,903	40,247
Past Due 31-59 Days	'	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	5,651
Total Past Due	'	5,651
Total Classified Nonaccrual	35,903	45,898
Commercial Real Estate [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	838,766	852,213
Commercial Real Estate [Member] | Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	802,863	816,357
Current	796,980	799,130
Past Due 31-59 Days	1,796	12,836
Past Due 60-89 Days	'	'
Past Due 90 or more Days	4,087	4,391
Total Past Due	5,883	17,227
Total Classified Nonaccrual	'	'
Commercial Real Estate [Member] | Nonaccrual Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	35,903	35,856
Current	35,903	32,701
Past Due 31-59 Days	'	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	3,155
Total Past Due	'	3,155
Total Classified Nonaccrual	35,903	35,856
Multifamily [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	210,270	208,699
Multifamily [Member] | Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	210,270	198,942
Current	209,426	198,942
Past Due 31-59 Days	844	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	'
Total Past Due	844	'
Total Classified Nonaccrual	'	'
Multifamily [Member] | Nonaccrual Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	'	9,757
Current	'	7,261
Past Due 31-59 Days	'	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	2,496
Total Past Due	'	2,496
Total Classified Nonaccrual	'	9,757
One to Four Family [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	72,064	41,676
One to Four Family [Member] | Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	72,064	41,676
Current	72,064	41,676
Past Due 31-59 Days	'	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	'
Total Past Due	'	'
Total Classified Nonaccrual	'	'
Land [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	9,178	7,167
Land [Member] | Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	9,178	6,882
Current	9,178	4,221
Past Due 31-59 Days	'	2,661
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	'
Total Past Due	'	2,661
Total Classified Nonaccrual	'	'
Land [Member] | Nonaccrual Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	'	285
Current	'	285
Past Due 31-59 Days	'	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	'
Total Past Due	'	'
Total Classified Nonaccrual	'	285
All Other [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	1,272	1,308
All Other [Member] | Accruing Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Total Portfolio	1,272	1,308
Current	1,271	1,308
Past Due 31-59 Days	1	'
Past Due 60-89 Days	'	'
Past Due 90 or more Days	'	'
Total Past Due	1	'
Total Classified Nonaccrual	'	'

Loans_Receivable_Age_Analysis_1

Loans Receivable - Age Analysis of Loan Portfolio by Segment (Parenthetical) (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Mortgage Loans on Real Estate [Line Items]	'	'
Current	$1,124,822	$1,085,524
Nonaccrual Loans [Member]	'	'
Mortgage Loans on Real Estate [Line Items]	'	'
Current	$33,200	$36,300

Loans_Receivable_Information_R

Loans Receivable - Information Regarding Credit Quality of Loan Portfolio (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	$1,131,550	$1,111,063
Allocation o allowance for loan losses	27,833	28,103
Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	838,766	852,213
Multifamily [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	210,270	208,699
One to Four Family [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	72,064	41,676
Land [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	9,178	7,167
All Other [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	1,272	1,308
Pass [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	1,058,087	1,016,424
Allocation o allowance for loan losses	20,720	20,037
Pass [Member] | Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	772,900	775,136
Pass [Member] | Multifamily [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	204,298	193,738
Pass [Member] | One to Four Family [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	72,064	41,676
Pass [Member] | Land [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	7,553	4,566
Pass [Member] | All Other [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	1,272	1,308
Special Mention [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	5,891	19,425
Allocation o allowance for loan losses	169	443
Special Mention [Member] | Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	3,522	17,041
Special Mention [Member] | Multifamily [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	2,369	2,384
Special Mention [Member] | One to Four Family [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	'	'
Special Mention [Member] | Land [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	'	'
Special Mention [Member] | All Other [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	'	'
Substandard [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	67,572	75,214
Allocation o allowance for loan losses	6,944	7,623
Substandard [Member] | Commercial Real Estate [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	62,344	60,036
Substandard [Member] | Multifamily [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	3,603	12,577
Substandard [Member] | One to Four Family [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	'	'
Substandard [Member] | Land [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	1,625	2,601
Substandard [Member] | All Other [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total loans	'	'

Loans_Receivable_Information_R1

Loans Receivable - Information Regarding Credit Quality of Loan Portfolio (Parenthetical) (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
	Security_Loan	SecurityLoan
Financing Receivable, Recorded Investment [Line Items]	'	'
Total Financing Receivable by TDRs	$46,613	$56,367
Number of rated pass accruing TDR	1	4
Nonaccrual Loans [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total Financing Receivable by TDRs	35,900	45,900
Accruing Loans [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total Financing Receivable by TDRs	13,100	20,100
All Other [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total Financing Receivable by TDRs	18,600	9,200
Pass [Member] | Accruing Loans One [Member]	'	'
Financing Receivable, Recorded Investment [Line Items]	'	'
Total Financing Receivable by TDRs	$400	'

Loans_Receivable_Geographic_Di

Loans Receivable - Geographic Distribution of Loan Portfolio (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	$1,131,550	$1,111,063
Total Loan Receivable, % of Total	100.00%	100.00%
New York [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	670,052	717,141
Total Loan Receivable, % of Total	59.20%	64.50%
Florida [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	321,812	286,619
Total Loan Receivable, % of Total	28.40%	25.80%
North Carolina [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	22,611	14,256
Total Loan Receivable, % of Total	2.00%	1.30%
Georgia [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	18,799	11,752
Total Loan Receivable, % of Total	1.70%	1.10%
Pennsylvania [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	16,898	10,270
Total Loan Receivable, % of Total	1.50%	0.90%
New Jersey [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	15,650	26,425
Total Loan Receivable, % of Total	1.40%	2.40%
Kentucky [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	11,930	7,512
Total Loan Receivable, % of Total	1.10%	0.70%
Virginia [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	11,491	11,758
Total Loan Receivable, % of Total	1.00%	1.10%
South Carolina [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	9,223	5,853
Total Loan Receivable, % of Total	0.80%	0.50%
Connecticut [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	8,429	11,216
Total Loan Receivable, % of Total	0.70%	1.00%
Tennessee [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	5,843	770
Total Loan Receivable, % of Total	0.50%	0.10%
Michigan [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	5,599	450
Total Loan Receivable, % of Total	0.50%	0.00%
Ohio [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	4,703	2,260
Total Loan Receivable, % of Total	0.40%	0.20%
Indiana [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	2,820	1,098
Total Loan Receivable, % of Total	0.20%	0.10%
All Other States [Member]	'	'
Noncancelable Obligations Future Minimum Payments Due [Line Items]	'	'
Total loans	$5,690	$3,683
Total Loan Receivable, % of Total	0.50%	0.30%

Loans_Receivable_Information_R2

Loans Receivable - Information Regarding Loans Restructured (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
	Security_Loan	SecurityLoan
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Number of Loans	1	4
Loans restructured, Pre-Modification Recorded Investment	'	$7,335
Loans restructured, Post-Modification Recorded Investment	'	7,335
Commercial Real Estate [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Number of Loans	2	1
Loans restructured, Pre-Modification Recorded Investment	9,159	5,010
Loans restructured, Post-Modification Recorded Investment	9,159	5,010
Multifamily [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Number of Loans	'	1
Loans restructured, Pre-Modification Recorded Investment	'	1,805
Loans restructured, Post-Modification Recorded Investment	'	1,805
Land [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Number of Loans	'	2
Loans restructured, Pre-Modification Recorded Investment	'	520
Loans restructured, Post-Modification Recorded Investment	'	$520

Loans_Receivable_Distribution_

Loans Receivable - Distribution of TDRs by Accruing Versus Non-Accruing, by Segment and by Geographic (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	$46,613	$56,367
Total Financing Receivable by TDRs	46,613	56,367
Total Financing Receivable by TDRs	46,613	56,367
New York [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	8,223	18,478
Total Financing Receivable by TDRs	8,223	18,478
Total Financing Receivable by TDRs	8,223	18,478
Florida [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	27,070	33,920
Total Financing Receivable by TDRs	27,070	33,920
Total Financing Receivable by TDRs	27,070	33,920
New Jersey [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	'	883
Total Financing Receivable by TDRs	'	883
Total Financing Receivable by TDRs	'	883
Georgia [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	8,695	'
Total Financing Receivable by TDRs	8,695	'
Total Financing Receivable by TDRs	8,695	'
Ohio [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	1,000	1,000
Total Financing Receivable by TDRs	1,000	1,000
Total Financing Receivable by TDRs	1,000	1,000
SD [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	1,625	2,086
Total Financing Receivable by TDRs	1,625	2,086
Total Financing Receivable by TDRs	1,625	2,086
Commercial Real Estate [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	41,860	43,685
Total Financing Receivable by TDRs	41,860	43,685
Total Financing Receivable by TDRs	41,860	43,685
Multifamily [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	3,128	10,081
Total Financing Receivable by TDRs	3,128	10,081
Total Financing Receivable by TDRs	3,128	10,081
Land [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	1,625	2,601
Total Financing Receivable by TDRs	1,625	2,601
Total Financing Receivable by TDRs	1,625	2,601
Non-accrual Status [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	33,200	36,300
Total Financing Receivable by TDRs	33,200	36,300
Total Financing Receivable by TDRs	33,200	36,300
Performing [Member] | Non-accrual Status [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	33,184	36,291
Total Financing Receivable by TDRs	33,184	36,291
Total Financing Receivable by TDRs	33,184	36,291
Performing [Member] | Accrual Status [Member]	'	'
Financing Receivable Modifications Number Of Contracts [Line Items]	'	'
Total Financing Receivable by TDRs	13,429	20,076
Total Financing Receivable by TDRs	13,429	20,076
Total Financing Receivable by TDRs	$13,429	$20,076

Allowance_for_Loan_Losses_Allo

Allowance for Loan Losses - Allowance for Loan Losses by Loan Type (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	$28,103	'	'	'	$30,415	$28,103	$30,415	$34,840
Loan chargeoffs	'	'	'	'	'	'	'	'	-1,938	-3,152	-9,598
Loan recoveries	'	'	'	'	'	'	'	'	2,218	840	155
Provision (credit) for loan losses	950	250	-750	-1,000	'	'	'	'	-550	'	5,018
Balance at end of period	27,833	'	'	'	28,103	'	'	'	27,833	28,103	30,415
Commercial Real Estate [Member]	'	'	'	'	'	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	19,051	'	'	'	19,156	19,051	19,156	21,919
Loan chargeoffs	'	'	'	'	'	'	'	'	-1,932	-2,588	-7,186
Loan recoveries	'	'	'	'	'	'	'	'	1,053	507	90
Provision (credit) for loan losses	'	'	'	'	'	'	'	'	231	1,976	4,333
Balance at end of period	18,403	'	'	'	19,051	'	'	'	18,403	19,051	19,156
Multifamily [Member]	'	'	'	'	'	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	6,881	'	'	'	8,848	6,881	8,848	11,234
Loan chargeoffs	'	'	'	'	'	'	'	'	-6	-564	-2,412
Loan recoveries	'	'	'	'	'	'	'	'	682	333	65
Provision (credit) for loan losses	'	'	'	'	'	'	'	'	-2,460	-1,736	-39
Balance at end of period	5,097	'	'	'	6,881	'	'	'	5,097	6,881	8,848
One to Four Family [Member]	'	'	'	'	'	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	1,120	'	'	'	332	1,120	332	122
Provision (credit) for loan losses	'	'	'	'	'	'	'	'	1,897	788	210
Balance at end of period	3,017	'	'	'	1,120	'	'	'	3,017	1,120	332
Land [Member]	'	'	'	'	'	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	1,043	'	'	'	2,069	1,043	2,069	1,553
Loan recoveries	'	'	'	'	'	'	'	'	483	'	'
Provision (credit) for loan losses	'	'	'	'	'	'	'	'	-218	-1,026	516
Balance at end of period	1,308	'	'	'	1,043	'	'	'	1,308	1,043	2,069
All Other [Member]	'	'	'	'	'	'	'	'	'	'	'
Financing Receivable, Allowance for Credit Losses [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Balance at beginning of period	'	'	'	'	'	'	'	10	'	10	12
Provision (credit) for loan losses	'	'	'	'	'	'	'	'	'	-2	-2
Balance at end of period	$8	'	'	'	$8	'	'	'	$8	$8	$10

Allowance_for_Loan_Losses_Loan

Allowance for Loan Losses - Loans Receivable by Segment and Impairment Evaluation and Allowance for Loan Losses (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
Loans:	'	'	'	'
Individually evaluated for impairment	$57,160	$65,973	'	'
Collectively evaluated for impairment	1,074,390	1,045,090	'	'
Total loans	1,131,550	1,111,063	'	'
Allowance for loan losses:	'	'	'	'
Individually evaluated for impairment	6,093	5,888	'	'
Collectively evaluated for impairment	21,740	22,215	'	'
Total allowance for loan losses	27,833	28,103	30,415	34,840
Commercial Real Estate [Member]	'	'	'	'
Loans:	'	'	'	'
Individually evaluated for impairment	52,407	50,795	'	'
Collectively evaluated for impairment	786,359	801,418	'	'
Total loans	838,766	852,213	'	'
Allowance for loan losses:	'	'	'	'
Individually evaluated for impairment	4,999	3,825	'	'
Collectively evaluated for impairment	13,404	15,226	'	'
Total allowance for loan losses	18,403	19,051	'	'
Multifamily [Member]	'	'	'	'
Loans:	'	'	'	'
Individually evaluated for impairment	3,128	12,577	'	'
Collectively evaluated for impairment	207,142	196,122	'	'
Total loans	210,270	208,699	'	'
Allowance for loan losses:	'	'	'	'
Individually evaluated for impairment	594	1,542	'	'
Collectively evaluated for impairment	4,503	5,339	'	'
Total allowance for loan losses	5,097	6,881	'	'
One to Four Family [Member]	'	'	'	'
Loans:	'	'	'	'
Collectively evaluated for impairment	72,064	41,676	'	'
Total loans	72,064	41,676	'	'
Allowance for loan losses:	'	'	'	'
Collectively evaluated for impairment	3,017	1,120	'	'
Total allowance for loan losses	3,017	1,120	'	'
Land [Member]	'	'	'	'
Loans:	'	'	'	'
Individually evaluated for impairment	1,625	2,601	'	'
Collectively evaluated for impairment	7,553	4,566	'	'
Total loans	9,178	7,167	'	'
Allowance for loan losses:	'	'	'	'
Individually evaluated for impairment	500	521	'	'
Collectively evaluated for impairment	808	522	'	'
Total allowance for loan losses	1,308	1,043	'	'
All Other [Member]	'	'	'	'
Loans:	'	'	'	'
Collectively evaluated for impairment	1,272	1,308	'	'
Total loans	1,272	1,308	'	'
Allowance for loan losses:	'	'	'	'
Collectively evaluated for impairment	8	8	'	'
Total allowance for loan losses	$8	$8	'	'

Premises_and_Equipment_Lease_C2

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income - Premises and Equipment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Total cost	$9,977	$9,686
Less accumulated depreciation and amortization	-5,921	-5,808
Net book value	4,056	3,878
Land [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Total cost	1,264	1,264
Buildings [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Total cost	5,214	5,020
Leasehold Improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Total cost	1,786	1,632
Furniture, Fixtures and Equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Total cost	$1,713	$1,770

Premises_and_Equipment_Lease_C3

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property Subject to or Available for Operating Lease [Line Items]	'	'	'
Depreciation and amortization of premises and equipment	$353	$345	$357
Premises and Equipment [Member]	'	'	'
Property Subject to or Available for Operating Lease [Line Items]	'	'	'
Depreciation and amortization of premises and equipment	$400	$400	$400
One Rockefeller Plaza [Member]	'	'	'
Property Subject to or Available for Operating Lease [Line Items]	'	'	'
Lease expiration date	'2024-03	'	'
Belcher Road [Member]	'	'	'
Property Subject to or Available for Operating Lease [Line Items]	'	'	'
Lease expiration date	'2022-09	'	'
Mandalay Avenue [Member]	'	'	'
Property Subject to or Available for Operating Lease [Line Items]	'	'	'
Lease expiration date	'2016-01	'	'

Premises_and_Equipment_Lease_C4

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income - Future Minimum Annual Lease Payments and Sublease Income Due under Non-Cancelable Leases (Detail) (USD $)	Dec. 31, 2013
Leases [Abstract]	'
In 2014, Lease Expense	$1,540,000
In 2015, Lease Expense	1,569,000
In 2016, Lease Expense	1,506,000
In 2017, Lease Expense	1,504,000
In 2018, Lease Expense	1,507,000
In 2019 and thereafter, Lease Expense	8,314,000
Total, Lease Expense	15,940,000
In 2014, Sublease Income	276
In 2015, Sublease Income	245
In 2016, Sublease Income	229
In 2017, Sublease Income	153
In 2018, Sublease Income	'
In 2019 and thereafter, Sublease Income	'
Total, Sublease Income	$903

Premises_and_Equipment_Lease_C5

Premises and Equipment, Lease Commitments, Rental Expense and Sublease Income - Future Minimum Annual Lease Payments and Sublease Income Due under Non-Cancelable Leases (Parenthetical) (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Leases [Abstract]	'	'	'
Rent expense	$1.60	$1.50	$1.20
Lease rental income	$0.40	$0.40	$0.40

Foreclosed_Real_Estate_and_Val2

Foreclosed Real Estate and Valuation Allowance for Real Estate Losses - Summary of Real Estate Acquired through Foreclosure by Property Type (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Property	Property
Real Estate Properties [Line Items]	'	'
# of Properties	3	6
Amount	$10,669	$15,923
Commercial Real Estate [Member]	'	'
Real Estate Properties [Line Items]	'	'
# of Properties	2	2
Amount	3,984	2,790
Multifamily [Member]	'	'
Real Estate Properties [Line Items]	'	'
# of Properties	1	3
Amount	6,685	12,000
Land [Member]	'	'
Real Estate Properties [Line Items]	'	'
# of Properties	'	1
Amount	'	$1,133

Foreclosed_Real_Estate_and_Val3

Foreclosed Real Estate and Valuation Allowance for Real Estate Losses - Summary of Activity in the Valuation Allowance for Real Estate Losses (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Real Estate Properties [Line Items]	'	'	'
Valuation allowance at beginning of year	$5,339	$6,037	$2,688
Provision for real estate losses charged to expense	1,105	4,068	3,349
Real estate chargeoffs	-4,427	-4,766	'
Valuation allowance at end of year	2,017	5,339	6,037
Commercial Real Estate [Member]	'	'	'
Real Estate Properties [Line Items]	'	'	'
Real estate chargeoffs	-256	-2,280	'
Multifamily [Member]	'	'	'
Real Estate Properties [Line Items]	'	'	'
Real estate chargeoffs	-3,157	'	'
Land [Member]	'	'	'
Real Estate Properties [Line Items]	'	'	'
Real estate chargeoffs	($1,014)	($2,486)	'

Deposits_Scheduled_Maturities_

Deposits - Scheduled Maturities of Certificates of Deposits (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Time Deposits By Maturity [Abstract]	'	'
Within one year, Amount	$307,122	$519,236
Over one to two years, Amount	167,323	181,698
Over two to three years, Amount	170,956	89,049
Over three to four years, Amount	106,700	60,119
Over four years, Amount	129,678	86,776
Total certificates of deposit, Amount	$881,779	$936,878
Within one year, Wtd-Avg Stated Rate	1.97%	2.92%
Over one to two years, Wtd-Avg Stated Rate	1.92%	2.79%
Over two to three years, Wtd-Avg Stated Rate	1.92%	2.74%
Over three to four years, Wtd-Avg Stated Rate	2.50%	3.02%
Over four years, Wtd-Avg Stated Rate	2.06%	2.93%
Total certificates of deposit, Wtd-Avg Stated Rate	2.03%	2.89%

Deposits_Additional_Informatio

Deposits - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Assets Sold under Agreements to Repurchase [Line Items]	'	'
CDs of $100,000 or more	$473,000,000	$463,000,000
Brokered certificate deposits amount	91,000,000	78,000,000
Due within one year	307,122,000	519,236,000
Due over one to two years	167,323,000	181,698,000
Due over two to three years	170,956,000	89,049,000
Due over three to four years	106,700,000	60,119,000
Due thereafter	129,678,000	86,776,000
Business Interests	3,700,000	3,400,000
CDs of $100,000 or More [Member]	'	'
Assets Sold under Agreements to Repurchase [Line Items]	'	'
Due within one year	143,000,000	'
Due over one to two years	75,000,000	'
Due over two to three years	107,000,000	'
Due over three to four years	67,000,000	'
Due thereafter	81,000,000	'
Brokered CDs [Member]	'	'
Assets Sold under Agreements to Repurchase [Line Items]	'	'
Due within one year	23,000,000	'
Due over one to two years	5,000,000	'
Due over two to three years	13,000,000	'
Due over three to four years	29,000,000	'
Due thereafter	$21,000,000	'
Brokered certificates deposits weighted average rate	3.01%	'

Deposits_Interest_Expense_on_D

Deposits - Interest Expense on Deposit Accounts (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]	'	'	'
Interest expense on deposit, Total	$25,430	$35,831	$47,582
Interest Checking Accounts [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Interest expense on deposit, Total	65	65	79
Savings Accounts [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Interest expense on deposit, Total	29	34	58
Money Market Accounts [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Interest expense on deposit, Total	1,530	2,142	3,669
Certificates of Deposit Accounts [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Interest expense on deposit, Total	$23,806	$33,590	$43,776

FHLB_Advances_and_Lines_of_Cre2

FHLB Advances and Lines of Credit - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]	'	'	'	'
FHLB advances repaid	$7	'	'	'
Loss on extinguishment of advances	0.2	0.2	0.2	0.2
Federal Home Loan Bank of New York and Federal Reserve Bank of New York [Member]	'	'	'	'
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]	'	'	'	'
Unsecured credit lines	'	24	'	'
Available collateral investment securities and loans pledged to support additional borrowings	'	$403	'	'

FHLB_Advances_and_Lines_of_Cre3

FHLB Advances and Lines of Credit - Summary of Certain Information Regarding INB Borrowings (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Debt Disclosure [Abstract]	'	'	'
Balance at year end	'	'	$17,500
Maximum amount outstanding at any month end during the year	'	13,500	25,500
Average outstanding balance for the year	$295	$9,087	$21,574
Weighted-average interest rate paid for the year	0.38%	4.27%	4.10%
Weighted-average interest rate at year end	'	'	4.10%

Subordinated_Debentures_Capita2

Subordinated Debentures - Capital Securities - Summary of Capital Securities Outstanding (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'	'
Accrued Interest Payable	$868	$6,228
Capital Securities II [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal	15,464	15,464
Accrued Interest Payable	275	1,661
Interest Rate	3.19%	3.26%
Capital Securities III [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal	15,464	15,464
Accrued Interest Payable	261	1,577
Interest Rate	3.03%	3.10%
Capital Securities IV [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal	15,464	15,464
Accrued Interest Payable	223	1,370
Interest Rate	2.65%	2.71%
Capital Securities V [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal	10,310	10,310
Accrued Interest Payable	109	1,620
Interest Rate	1.89%	1.96%
Capital Securities [Member]	'	'
Debt Instrument [Line Items]	'	'
Principal	56,702	56,702
Accrued Interest Payable	$868	$6,228

Subordinated_Debentures_Capita3

Subordinated Debentures - Capital Securities - Summary of Capital Securities Outstanding (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2013
Capital Securities II [Member]	'
Debt Instrument [Line Items]	'
Subordinated debentures due date	17-Sep-33
Capital Securities III [Member]	'
Debt Instrument [Line Items]	'
Subordinated debentures due date	17-Mar-34
Capital Securities IV [Member]	'
Debt Instrument [Line Items]	'
Subordinated debentures due date	20-Sep-34
Capital Securities V [Member]	'
Debt Instrument [Line Items]	'
Subordinated debentures due date	15-Dec-36

Subordinated_Debentures_Capita4

Subordinated Debentures - Capital Securities - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013
Debt Instrument [Line Items]	'
Capital securities, net of IBC's capital contributions	$55
IBC's capital contributions	1.7
Unamortized balance of issuance costs	0.7
Capital Securities V [Member]	'
Debt Instrument [Line Items]	'
Capital securities issuance costs	$0
Frequency of periodic interest payment	'Quarterly
Debt instrument interest rate	1.65%
Debt instrument, interest rate terms	'1.65% over 3 month libor
Junior Subordinated Debentures [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, limit on extension periods	20
Debt instrument, interest payment, maximum extension period	'5 years
Capital securities, mandatory maturity period	'90 days
Capital Securities II [Member]	'
Debt Instrument [Line Items]	'
Frequency of periodic interest payment	'Quarterly
Debt instrument interest rate	2.95%
Debt instrument, interest rate terms	'2.95% over 3 month libor
Capital Securities III [Member]	'
Debt Instrument [Line Items]	'
Frequency of periodic interest payment	'Quarterly
Debt instrument interest rate	2.79%
Debt instrument, interest rate terms	'2.79% over 3 month libor
Capital Securities IV [Member]	'
Debt Instrument [Line Items]	'
Frequency of periodic interest payment	'Quarterly
Debt instrument interest rate	2.40%
Debt instrument, interest rate terms	'2.40% over 3 month libor

Stockholders_Equity_and_Redemp1

Stockholders' Equity and Redemption of Preferred Stock - Additional Information (Detail) (USD $)	0 Months Ended			12 Months Ended
	Aug. 15, 2013	Jun. 24, 2013	Jun. 13, 2013	Dec. 31, 2013	Dec. 31, 2012
				Stock_Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Classes of authorized common stock	'	'	'	2	'
Capital stock, shares authorized to issue	'	'	'	62,300,000	'
Common stock, shares authorized	'	'	'	62,000,000	62,000,000
Preferred stock, shares authorized	'	'	'	300,000	300,000
Preferred stock, stock issued	'	'	'	'	25,000
Duration of warrant	'	'10 years	'	'	'
Number of shares to be exercised upon warrants	'	691,882	'	'	'
Conversion price for warrants	'	$5.42	'	'	'
Treasury auctioned shares	'	'	25,000	'	'
Number of preferred stock	'	'	6,250	'	'
Purchase of preferred stock shares by third parties	'	'	18,750	'	'
Closing price of the auctioned shares	'	'	$970	'	'
Number of preferred stock repurchased	'	6,250	'	'	'
Rate of repurchase of shares	'	$6,100,000	'	'	'
Additional accrued and unpaid dividends	'	1,200,000	'	'	'
Total shares repurchase	'	7,300,000	'	'	'
Preferred Stock outstanding redeemed	18,750	'	'	'	'
Effective date of the planned redemption	15-Aug-13	'	'	'	'
Purchase price of shares	$1,000	'	'	'	'
Total expected cost to redeem shares	22,600,000	'	'	'	'
Preferred dividends	$3,900,000	'	'	'	'
Warrant [Member]	'	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'
Preferred stock, stock issued	'	25,000	'	'	'

Asset_and_Dividend_Restriction1

Asset and Dividend Restrictions - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]	'	'	'
Total capital to risk-weighted assets, Required	$98,320,000	$99,042,000	'
Investment	8,200,000	8,200,000	'
Mortgage loans	71,000,000	105,000,000	'
Common stock dividend declared or paid not in cash	0	0	0
US Government Corporations and Agencies Securities [Member]	'	'	'
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]	'	'	'
U.S. government agency security investments	$27,000,000	$17,000,000	'

Profit_Sharing_Plans_Additiona

Profit Sharing Plans - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation And Retirement Disclosure [Abstract]	'	'	'
Employee compensation contribution	4.00%	'	'
Vesting period	'5 years	'	'
Total cash contributions	$164,000	$161,000	$141,000

Common_Stock_Warrant_Options_a2

Common Stock Warrant, Options and Restricted Common Stock - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Stock-based compensation expense	$0.80	$1.20	$0.30
Pre-tax, stock-based compensation cost related to all nonvested awards of options and restricted stock not yet recognized	1.9	'	'
Options and restricted stock not yet recognized and will be recognized over a weighted-average period	'1 year 10 months 24 days	'	'
Net tax benefit	$0.60	$0	$0
Long Term Incentive Plan [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Maximum number of shares of common stock that may be awarded	2,250,000	'	'
Common stock were available for award	789,003	'	'

Common_Stock_Warrant_Options_a3

Common Stock Warrant, Options and Restricted Common Stock - Summary of Selected Information Regarding Option Awards Made Under Plans (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Date of award	8-Dec-11
Total options awarded	44,100
Exercise price of option	$2.55
Estimated fair value per option	$1.67
Total estimated fair value of award	$73,647
Assumptions used in Black-Scholes Model:	'
Expected dividend yield	0.00%
Expected stock volatility	75.00%
Risk-free interest rate	1.13%
Expected term in years	'6 years

Common_Stock_Warrant_Options_a4

Common Stock Warrant, Options and Restricted Common Stock - Summary of the Activity in IBC's Outstanding Common Stock Warrant and Options (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Beginning Outstanding	1,078,122	1,085,622	1,045,422
Forfeited/expired	-19,410	-7,400	-3,900
Options granted	'	'	44,100
Ending Outstanding	1,041,445	1,078,122	1,085,622
Options exercised	-17,267	-100	'
Vested and exercisable	99.00%	'	'
Wtd-avg contractual remaining term (in years)	'5 years 1 month 6 days	'	'
Intrinsic value at December 31, 2013	$1,968	'	'
Wtd-Avg Exercise Price, Beginning Outstanding	$6.63	$6.62	$6.79
Wtd-Avg Exercise Price, Forfeited/expired	$8.80	$6.13	$5.44
Wtd-Avg Exercise Price, Options granted	'	'	$2.55
Wtd-Avg Exercise Price, Ending Outstanding	$6.64	$6.63	$6.62
Wtd-Avg Exercise Price, Exercised	$3.49	$3	'
Exercise Price Per Warrant/Option $5.42 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$5.42
Beginning Outstanding	691,882	'	691,882
Ending Outstanding	691,882	'	691,882
Expiration date	23-Dec-18	'	'
Vested and exercisable	100.00%	'	'
Wtd-avg contractual remaining term (in years)	'5 years	'	'
Intrinsic value at December 31, 2013	1,446	'	'
Exercise Price Per Warrant/Option $17.10 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$17.10
Beginning Outstanding	116,640	117,840	118,140
Forfeited/expired	-6,000	-1,200	-300
Ending Outstanding	110,640	116,640	117,840
Expiration date	13-Dec-17	'	'
Vested and exercisable	100.00%	'	'
Wtd-avg contractual remaining term (in years)	'4 years	'	'
Exercise Price Per Warrant/Option $7.50 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$7.50
Beginning Outstanding	120,190	121,390	122,290
Forfeited/expired	-6,200	-1,200	-900
Ending Outstanding	113,990	120,190	121,390
Expiration date	11-Dec-18	'	'
Vested and exercisable	100.00%	'	'
Wtd-avg contractual remaining term (in years)	'4 years 10 months 24 days	'	'
Intrinsic value at December 31, 2013	1	'	'
Exercise Price Per Warrant/Option $4.02 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$4.02
Beginning Outstanding	68,910	70,510	71,710
Forfeited/expired	-1,610	-1,600	-1,200
Ending Outstanding	57,400	68,910	70,510
Options exercised	-9,900	'	'
Expiration date	10-Dec-19	'	'
Vested and exercisable	100.00%	'	'
Wtd-avg contractual remaining term (in years)	'5 years 10 months 24 days	'	'
Intrinsic value at December 31, 2013	201	'	'
Exercise Price Per Warrant/Option $3.00 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$3
Beginning Outstanding	38,200	39,900	41,400
Forfeited/expired	-2,100	-1,600	-1,500
Ending Outstanding	32,400	38,200	39,900
Options exercised	-3,700	-100	'
Expiration date	9-Dec-20	'	'
Vested and exercisable	100.00%	'	'
Wtd-avg contractual remaining term (in years)	'6 years 10 months 24 days	'	'
Intrinsic value at December 31, 2013	146	'	'
Exercise Price Per Warrant/Option $2.55 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Exercise Price Per Warrant/Option	'	'	$2.55
Beginning Outstanding	42,300	44,100	'
Forfeited/expired	-3,500	-1,800	'
Options granted	'	'	44,100
Ending Outstanding	35,133	42,300	44,100
Options exercised	-3,667	'	'
Expiration date	8-Dec-21	'	'
Vested and exercisable	67.00%	'	'
Wtd-avg contractual remaining term (in years)	'7 years 10 months 24 days	'	'
Intrinsic value at December 31, 2013	$174	'	'

Common_Stock_Warrant_Options_a5

Common Stock Warrant, Options and Restricted Common Stock - Summary of the Activity in IBC's Outstanding Common Stock Warrant and Options (Parenthetical) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Vested and exercisable	99.00%
Calculated intrinsic value	$7.51
Price Per Share $2.55 [Member]	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'
Exercise Price Per Warrant/Option	$2.55
Vested and exercisable	100.00%

Common_Stock_Warrant_Options_a6

Common Stock Warrant, Options and Restricted Common Stock - Summary of Selected Information Regarding Restricted Common Stock Awards Made Under Plans (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 12, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Grant date of award, Stock Grant	12-Dec-13	24-Jan-13	19-Jan-12
Total restricted shares of stock awarded	135,500	330,700	465,400
Estimated fair value per share awarded	$7.21	$4.50	$2.90
Total estimated fair value of award	$977	$1,488	$1,350
Awards scheduled to vest as follows:	'	'	'
Awards scheduled to vest, Stock Grant	135,500	330,700	465,400
January 2013 [Member]	'	'	'
Awards scheduled to vest as follows:	'	'	'
Awards scheduled to vest, Stock Grant	'	'	256,800
January 2014 [Member]	'	'	'
Awards scheduled to vest as follows:	'	'	'
Awards scheduled to vest, Stock Grant	75,417	49,566	133,455
January 2015 [Member]	'	'	'
Awards scheduled to vest as follows:	'	'	'
Awards scheduled to vest, Stock Grant	44,917	170,888	75,145
January 2016 [Member]	'	'	'
Awards scheduled to vest as follows:	'	'	'
Awards scheduled to vest, Stock Grant	15,166	110,246	'

Common_Stock_Warrant_Options_a7

Common Stock Warrant, Options and Restricted Common Stock - Summary of Selected Information Regarding Restricted Common Stock Awards Made Under Plans (Parenthetical) (Detail)

12 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

1 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Jan. 31, 2013

Jan. 31, 2012

Dec. 31, 2013

Jan. 31, 2013

Jan. 31, 2012

Jan. 31, 2013

Jan. 31, 2012

Jan. 31, 2013

Jan. 31, 2012

Jan. 31, 2013

Jan. 31, 2012

Jan. 31, 2013

Jan. 31, 2012

Restricted Common Stock [Member]

Restricted Common Stock [Member]

Executive Officers [Member]

Executive Officers [Member]

Executive Officers [Member]

Executive Officers [Member]

Executive Officers [Member]

Non-employee Directors [Member]

Non-employee Directors [Member]

Non-employee Directors [Member]

Non-employee Directors [Member]

Other Officers and Employees [Member]

Other Officers and Employees [Member]

Other Officers and Employees [Member]

Other Officers and Employees [Member]

Installment

Installment

Installment

Restricted Common Stock [Member]

Restricted Common Stock [Member]

Executives

Executives

Restricted Common Stock [Member]

Restricted Common Stock [Member]

Installment

Installment

Restricted Common Stock [Member]

Restricted Common Stock [Member]

Executives

Executives

Executives

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

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of participants

'

'

5

5

5

'

'

8

6

'

'

'

'

'

'

Number of installments

'

'

2

2

5

'

'

'

'

'

'

3

3

'

'

Vesting period

'

'

'

'

'3 years

'

'

'

'

'

'

'

'

'

'

Shares Awarded

466,200

465,400

'

'

'

182,000

175,000

'

'

80,000

240,000

'

'

68,700

50,400

Restricted stock awards vesting in second anniversary of the grant

'

'

66.67%

66.67%

'

'

'

33.33%

'

'

'

33.33%

33.33%

'

'

Restricted stock awards vesting in third anniversary of the grant

'

'

33.33%

33.33%

'

'

'

33.33%

'

'

'

33.33%

33.33%

'

'

Restricted stock awards vesting in first anniversary of the grant

'

'

'

'

'

'

'

33.33%

100.00%

'

'

33.33%

33.33%

'

'

Common_Stock_Warrant_Options_a8

Common Stock Warrant, Options and Restricted Common Stock - Summary of Activity in IBCs Restricted Class A Common Stock (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Shares forfeited	-154,433	'	'
Ending Outstanding	573,317	'	'
Restricted Common Stock [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Price Per Share	$7.21	'	'
Beginning Outstanding	782,300	318,100	319,300
Shares forfeited	'	-1,200	-1,200
Ending Outstanding	'	782,300	318,100
Shares granted	466,200	465,400	'
Shares vested and no longer restricted	-520,750	'	'
Price Per Share $2.35 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Shares forfeited	-53,350	'	'
Price Per Share $2.35 [Member] | Restricted Common Stock [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Price Per Share	'	'	2.35
Beginning Outstanding	317,500	318,100	319,300
Shares forfeited	'	-600	-1,200
Ending Outstanding	'	317,500	318,100
Shares vested and no longer restricted	-264,150	'	'
Price Per Share $2.90 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Shares forfeited	-49,883	'	'
Ending Outstanding	158,317	'	'
Price Per Share $2.90 [Member] | Restricted Common Stock [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Price Per Share	'	'	2.9
Beginning Outstanding	464,800	'	'
Shares forfeited	'	-600	'
Ending Outstanding	'	464,800	'
Shares granted	'	465,400	'
Shares vested and no longer restricted	-256,600	'	'
Price Per Share $4.50 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Shares forfeited	-51,200	'	'
Ending Outstanding	279,500	'	'
Price Per Share $4.50 [Member] | Restricted Common Stock [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Price Per Share	$4.50	'	4.5
Shares granted	330,700	'	'
Price Per Share $7.21 [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Ending Outstanding	135,500	'	'
Price Per Share $7.21 [Member] | Restricted Common Stock [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Price Per Share	'	'	7.21
Shares granted	135,500	'	'

Common_Stock_Warrant_Options_a9

Common Stock Warrant, Options and Restricted Common Stock - Summary of Activity in IBCs Restricted Class A Common Stock (Parenthetical) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2011
Restricted Common Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Exercise Price Per Warrant/Option	$7.21	'
Restricted common stock will vest on date 1Restricted common stock will vest on date 2	15,166	'
Restricted Common Stock [Member] | January 2, 2014 [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted common stock will vest on date 1	46,250	'
Restricted Common Stock [Member] | January 19, 2014 [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted common stock will vest on date 1	29,167	'
Restricted Common Stock [Member] | January 19, 2015 [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted common stock will vest on date 1	14,584	'
Restricted Common Stock [Member] | January 24, 2015 [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Restricted common stock will vest on date 1	30,333	'
Price Per Share $2.35 [Member] | Vest and Become Exercisable on December 9, 2013 [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Exercise Price Per Warrant/Option	$2.90	'
Price Per Share $2.35 [Member] | Restricted Common Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Exercise Price Per Warrant/Option	'	$2.35
Price Per Share $2.90 [Member] | Restricted Common Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Exercise Price Per Warrant/Option	'	$2.90
Restricted common stock will vest on date 1	101,034	'
Restricted common stock will vest on date 1	57,283	'
Price Per Share $4.50 [Member] | Restricted Common Stock [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Exercise Price Per Warrant/Option	$4.50	$4.50
Restricted common stock will vest on date 1	47,667	'
Restricted common stock will vest on date 1	138,667	'
Restricted common stock will vest on date 1Restricted common stock will vest on date 2	93,166	'

Income_Taxes_Allocation_of_Fed

Income Taxes - Allocation of Federal, State and Local Income Tax Expense Between Current and Deferred Portions (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Current Federal Tax Expense	'	'	'	'	'	'	'	'	$420	$370	$958
Current State and Local Tax Expense	'	'	'	'	'	'	'	'	339	335	311
Current Income Tax Expense, Total	'	'	'	'	'	'	'	'	759	705	1,269
Deferred Federal Income Tax Expense	'	'	'	'	'	'	'	'	9,130	7,751	6,670
Deferred State and Local Income Tax Expense	'	'	'	'	'	'	'	'	1,766	1,851	1,573
Deferred Income Tax Expense, Total	'	'	'	'	'	'	'	'	10,896	9,602	8,243
Federal Income Tax Expense, Total	'	'	'	'	'	'	'	'	9,550	8,121	7,628
State and Local Income Tax Expense, Total	'	'	'	'	'	'	'	'	2,105	2,186	1,884
Income Tax Expense, Total	$3,476	$2,300	$2,804	$3,075	$2,987	$2,300	$2,326	$2,694	$11,655	$10,307	$9,512

Income_Taxes_Components_of_the

Income Taxes - Components of the Deferred Tax Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
NOL and AMT credit carryforwards	$7,353	$8,084	$8,138
Allowances for loan losses and real estate losses	1,597	1,315	484
Capitalized real estate expenses and nonaccrual interest	36	1,011	-232
Impairment writedowns on investment securities	1,857	-282	-86
Deferred compensation and benefits	285	-355	-48
Depreciation	-234	-166	-16
Deferred income	2	-5	3
Deferred Income Tax Expense, Total	$10,896	$9,602	$8,243

Income_Taxes_Tax_Effects_of_th

Income Taxes - Tax Effects of the Temporary Differences in Deferred Tax Asset (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Income Tax Disclosure [Abstract]	'	'
NOL and AMT credit carryforwards	$3,061	$10,414
Allowances for loan losses and real estate losses	12,814	14,411
Capitalized real estate expenses and nonaccrual interest	1,152	1,188
Impairment writedowns on investment securities	'	1,857
Unrealized losses on securities available for sale	24	'
Deferred compensation and benefits	852	1,137
Depreciation	454	220
Deferred income	5	7
Total deferred tax asset	$18,362	$29,234

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Nov. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Loss Carryforwards [Line Items]	'	'	'	'
Income tax proposed adjustments to federal returns under audit	'	$0	'	'
NOL carryforwards expiration year	'	'2030	'	'
Annual franchise tax expense	0.2	0.2	0.2	0.2
State and Local [Member]	'	'	'	'
Operating Loss Carryforwards [Line Items]	'	'	'	'
Unused net operating loss carryforward	'	$30	'	'

Income_Taxes_Reconciliation_be

Income Taxes - Reconciliation between Statutory Federal Income Tax Rate and Our Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Federal statutory income tax rate	35.00%	35.00%	35.00%
State and local income tax rate, net of federal benefit	7.80%	9.40%	9.30%
All other	1.80%	1.40%	1.50%
Effective Income Tax Rate	44.60%	45.80%	45.80%

Earning_Per_Common_Share_Summa

Earning Per Common Share - Summary of Basic and Diluted Earnings Per Common Share (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basic Earnings Per Common Share:	'	'	'	'	'	'	'	'	'	'	'
Net earnings available to common stockholders	$4,207	$2,588	$3,213	$3,429	$3,074	$2,225	$2,312	$2,810	$13,437	$10,421	$9,516
Weighted-Average number of common shares outstanding	'	'	'	'	'	'	'	'	21,894,030	21,566,009	21,126,187
Basic earnings per common share	$0.19	$0.12	$0.14	$0.16	$0.14	$0.10	$0.11	$0.13	$0.61	$0.48	$0.45
Diluted Earnings Per Common Share:	'	'	'	'	'	'	'	'	'	'	'
Net earnings available to common stockholders	$4,207	$2,588	$3,213	$3,429	$3,074	$2,225	$2,312	$2,810	$13,437	$10,421	$9,516
Weighted-Average number of common shares outstanding:	'	'	'	'	'	'	'	'	'	'	'
Common shares outstanding	'	'	'	'	'	'	'	'	21,894,030	21,566,009	21,126,187
Potential dilutive shares resulting from exercise of warrants /options	'	'	'	'	'	'	'	'	99,596	2,187	'
Total average number of common shares outstanding used for dilution	'	'	'	'	'	'	'	'	21,993,626	21,568,196	21,126,187
Diluted earnings per common share	$0.19	$0.12	$0.14	$0.16	$0.14	$0.10	$0.11	$0.13	$0.61	$0.48	$0.45

Earning_Per_Common_Share_Summa1

Earning Per Common Share - Summary of Basic and Diluted Earnings Per Common Share (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Earnings Per Share [Abstract]	'	'	'
Outstanding options/warrants to purchase, shares	224,630	997,622	1,085,622

Contingencies_Additional_Infor

Contingencies - Additional Information (Detail) (USD $)	12 Months Ended		3 Months Ended		12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2013
	Security_Loan	SecurityLoan	INB [Member]	INB [Member]	INB [Member]
					SecurityLoan
Loss Contingencies [Line Items]	'	'	'	'	'
Net Proceeds of loans	'	'	$0.10	$2.70	'
Recovery of prior loan charge offs	'	'	'	'	1.2
Recovery of prior real estate expenses	'	'	'	'	$1.60
Number of loans associated with recoveries of prior real estate expenses	1	4	'	'	2

Contractual_Death_Benefit_Paym1

Contractual Death Benefit Payments - Additional Information (Detail) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Jun. 30, 2013
Schedule Of Contractual Death Benefit Payments [Line Items]	'	'
Remaining death benefit payment net	0.2	'
Agreement condition obligated to pay to Mr. Dansker's wife or his estate	'Greater of (i) three years, and (ii) the number of months remaining in the stated term of the agreement	'
Period of agreement under condition one	'3 years	'
Percentage of amount in the case of disability	50.00%	'
Percentage of amount in the case of death	25.00%	'
Provision for contingent liability	0	'
Mr. Lowell S. Dansker [Member]	'	'
Schedule Of Contractual Death Benefit Payments [Line Items]	'	'
Employment and supplemental benefits agreement	'10 years	'
Employment and supplemental benefits agreement expiry date	30-Jun-14	'
Salary under employment agreement	'	$1.20

OffBalance_Sheet_Financial_Ins2

Off-Balance Sheet Financial Instruments - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Off Balance Sheet Financial Instruments [Abstract]	'	'
Standby letters of credit	$0	$0

OffBalance_Sheet_Financial_Ins3

Off-Balance Sheet Financial Instruments - Summary of Contractual Amounts of Off-Balance Sheet Financial Instruments (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]	'	'
Standby letters of credit	$20,263	$20,008
Commitments to Extend Credit [Member]	'	'
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]	'	'
Standby letters of credit	19,386	19,154
Unused Lines of Credit [Member]	'	'
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]	'	'
Standby letters of credit	$877	$854

Regulatory_Capital_and_Regulat2

Regulatory Capital and Regulatory Matters - Summary of Regulatory Capital and Related Ratios (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Tier 1 capital	$245,191	$249,465
Tier 2 capital	15,517	15,620
Total risk-based capital	260,708	265,085
Net risk-weighted assets for regulatory purposes	1,228,994	1,238,024
Average assets for regulatory purposes	1,586,416	1,696,410
Total capital to risk-weighted assets	21.21%	21.41%
Tier 1 capital to risk-weighted assets	19.95%	20.15%
Tier 1 capital to average assets	15.46%	14.71%
INB [Member]	'	'
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Tier 1 capital	240,918	244,081
Tier 2 capital	15,479	15,566
Total risk-based capital	256,397	259,647
Net risk-weighted assets for regulatory purposes	1,225,936	1,232,670
Average assets for regulatory purposes	$1,581,713	$1,690,329
Total capital to risk-weighted assets	20.91%	21.06%
Tier 1 capital to risk-weighted assets	19.65%	19.80%
Tier 1 capital to average assets	15.23%	14.44%

Regulatory_Capital_and_Regulat3

Regulatory Capital and Regulatory Matters - Summary of Regulatory Capital and Related Ratios (Parenthetical) (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Banking And Thrift [Abstract]	'	'
Outstanding qualifying trust preferred securities	$55	$55

Regulatory_Capital_and_Regulat4

Regulatory Capital and Regulatory Matters - Capital Adequacy (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Total capital to risk-weighted assets, Actual Capital, Amount	$260,708	$265,085
Tier 1 capital to risk-weighted assets, Actual Capital, Amount	245,191	249,465
Tier 1 capital to average assets, Actual Capital, Amount	245,191	249,465
Total capital to risk-weighted assets, Actual Capital, Ratio	21.21%	21.41%
Tier 1 capital to risk-weighted assets, Actual Capital, Ratio	19.95%	20.15%
Tier 1 capital to average assets, Actual Capital, Ratio	15.46%	14.71%
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	98,320	99,042
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	49,160	49,521
Tier 1 capital to average assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	63,457	67,856
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	4.00%	4.00%
Tier 1 capital to average assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	4.00%	4.00%
INB [Member]	'	'
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Total capital to risk-weighted assets, Actual Capital, Amount	256,397	259,647
Tier 1 capital to risk-weighted assets, Actual Capital, Amount	240,918	244,081
Tier 1 capital to average assets, Actual Capital, Amount	240,918	244,081
Total capital to risk-weighted assets, Actual Capital, Ratio	20.91%	21.06%
Tier 1 capital to risk-weighted assets, Actual Capital, Ratio	19.65%	19.80%
Tier 1 capital to average assets, Actual Capital, Ratio	15.23%	14.44%
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	98,075	98,614
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	49,037	49,307
Tier 1 capital to average assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Amount	63,269	67,613
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	4.00%	4.00%
Tier 1 capital to average assets, Capital Requirements, Minimum Under Prompt Corrective Action Provisions, Ratio	4.00%	4.00%
Total capital to risk-weighted assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Amount	122,594	123,267
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Amount	73,556	73,960
Tier 1 capital to average assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Amount	79,086	84,516
Total capital to risk-weighted assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Ratio	6.00%	6.00%
Tier 1 capital to average assets, Capital Requirements, Minimum To Be "Well Capitalized" Under Prompt Corrective Action Provisions, Ratio	5.00%	5.00%
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Agreement With OCC, Amount	'	147,920
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Agreement With OCC, Amount	'	123,267
Tier 1 capital to average assets, Capital Requirements, Minimum Under Agreement With OCC, Amount	'	$152,130
Total capital to risk-weighted assets, Capital Requirements, Minimum Under Agreement With OCC, Ratio	'	12.00%
Tier 1 capital to risk-weighted assets, Capital Requirements, Minimum Under Agreement With OCC, Ratio	'	10.00%
Tier 1 capital to average assets, Capital Requirements, Minimum Under Agreement With OCC, Ratio	'	9.00%

Regulatory_Capital_and_Regulat5

Regulatory Capital and Regulatory Matters - Capital Adequacy (Parenthetical) (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Banking And Thrift [Abstract]	'	'
Outstanding qualifying trust preferred securities	$55	$55
Tier 1 proforma capital ratio	21.21%	'
Tier two proforma capital ratio	15.48%	'
Consolidated proforma capital ratio	11.99%	'

Regulatory_Capital_and_Regulat6

Regulatory Capital and Regulatory Matters - Additional Information Regarding Capital Adequacy (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Total capital to risk-weighted assets, Actual Capital, Amount	$260,708	$265,085
Tier 1 capital to risk-weighted assets, Actual Capital, Amount	245,191	249,465
Tier 1 capital to average assets, Actual	245,191	'
Total capital to risk-weighted assets, Required	98,320	99,042
Tier 1 capital to risk-weighted assets, Required	49,160	49,521
Tier 1 capital to average assets, Required	63,457	67,856
Total capital to risk-weighted assets, Excess	162,388	'
Tier 1 capital to risk-weighted assets, Excess	196,031	'
Tier 1 capital to average assets, Excess	181,734	'
INB [Member]	'	'
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]	'	'
Total capital to risk-weighted assets, Actual Capital, Amount	256,397	259,647
Tier 1 capital to risk-weighted assets, Actual Capital, Amount	240,918	244,081
Tier 1 capital to average assets, Actual	240,918	'
Total capital to risk-weighted assets, Required	122,594	123,267
Tier 1 capital to risk-weighted assets, Required	73,556	73,960
Tier 1 capital to average assets, Required	79,086	84,516
Total capital to risk-weighted assets, Required	98,075	98,614
Tier 1 capital to risk-weighted assets, Required	49,037	49,307
Tier 1 capital to average assets, Required	63,269	67,613
Total capital to risk-weighted assets, Excess	133,803	'
Tier 1 capital to risk-weighted assets, Excess	167,362	'
Tier 1 capital to average assets, Excess	$161,832	'

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Securities available for sale, net	$965	$1,000
Fair Value, Inputs, Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Securities available for sale, net	1,000	1,000
Liabilities that were recorded at fair value	$0	$0

Fair_Value_Measurements_Assets

Fair Value Measurements - Assets Measured at Fair Value on a Nonrecurring Basis (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Impaired Securities [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	'	$4,233	'
Total Losses (Gains)	-517	582	201
Foreclosure Real Estate [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	2,017	5,339	'
Total Losses (Gains)	142	4,161	3,161
Level 3 [Member] | Impaired Securities [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	'	3,721	'
Level 3 [Member] | Foreclosure Real Estate [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	10,669	15,923	'
Impaired Loans [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	11,392	13,592	'
Total Losses (Gains)	1,066	186	10,135
Impaired Loans [Member] | Commercial Real Estate [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	10,294	9,979	'
Total Losses (Gains)	2,053	1,038	4,936
Impaired Loans [Member] | Multifamily [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	598	3,092	'
Total Losses (Gains)	-966	-364	4,190
Impaired Loans [Member] | Land [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Accumulated Losses on Outstanding Balance	500	521	'
Total Losses (Gains)	-21	-488	1,009
Impaired Loans [Member] | Level 3 [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	57,160	65,973	'
Impaired Loans [Member] | Level 3 [Member] | Commercial Real Estate [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	52,407	50,795	'
Impaired Loans [Member] | Level 3 [Member] | Multifamily [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	3,128	12,577	'
Impaired Loans [Member] | Level 3 [Member] | Land [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Outstanding Carrying Value	$1,625	$2,601	'

Fair_Value_Measurements_Change

Fair Value Measurements - Change in Assets Measured at Fair Value on a Nonrecurring Basis (Detail) (Assets Measured at Fair Value on a Nonrecurring Basis [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Impaired Securities [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Beginning balance	$3,721	$4,378	$4,580
Principal repayments/sales	-4,238	-75	'
Other than temporary impairment writedowns	-964	-582	-201
Gain (Loss) on sales	1,481	'	'
All other	'	'	-1
Ending balance	'	3,721	4,378
Impaired Loans [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Beginning balance	65,973	66,269	56,555
Net new impaired loans	16,122	19,875	41,768
Principal repayments/sales	-19,957	-12,330	-18,198
Chargeoffs	-1,938	-3,152	-9,481
Transferred to foreclosed real estate	-3,040	-4,689	-4,375
Ending balance	57,160	65,973	66,269
Foreclosure Real Estate [Member]	'	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'	'
Beginning balance	15,923	28,278	27,064
Principal repayments/sales	-8,152	-12,883	'
Transferred to foreclosed real estate	3,040	4,689	4,375
Writedowns of carrying value subsequent to foreclosure	-1,105	-4,068	-3,349
Gain on sales/transfers from loans	'	'	188
Gain (Loss) on sales	963	-93	'
Ending balance	$10,669	$15,923	$28,278

Fair_Value_Measurements_Carryi

Fair Value Measurements - Carrying and Estimated Fair Values of Financial Instruments (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Financial Assets:	'	'
Securities available for sale, net	$965	$1,000
Securities held to maturity, net	378,507	442,166
Fair Value [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	24,700	60,395
Time deposits with banks	5,370	5,170
Securities available for sale, net	965	1,000
Securities held to maturity, net	378,507	442,166
FRB and FHLB stock	8,244	8,151
Loans receivable, net	1,100,858	1,102,333
Accrued interest receivable	4,861	5,191
Loan fees receivable	1,808	2,547
Total Financial Assets	1,525,313	1,626,953
Financial Liabilities:	'	'
Deposits	1,294,690	1,389,629
Borrowed funds plus accrued interest payable	57,260	62,448
Accrued interest payable on deposits	1,508	2,379
Commitments to lend	408	386
Total Financial Liabilities	1,353,866	1,454,842
Net Financial Assets	171,447	172,111
Carrying Value [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents	24,700	60,395
Time deposits with banks	5,370	5,170
Securities available for sale, net	965	1,000
Securities held to maturity, net	383,937	443,777
FRB and FHLB stock	8,244	8,151
Loans receivable, net	1,099,689	1,079,363
Accrued interest receivable	4,861	5,191
Loan fees receivable	2,298	3,108
Total Financial Assets	1,530,064	1,606,155
Financial Liabilities:	'	'
Deposits	1,282,232	1,362,619
Borrowed funds plus accrued interest payable	57,570	62,930
Accrued interest payable on deposits	1,508	2,379
Commitments to lend	408	386
Total Financial Liabilities	1,341,718	1,428,314
Net Financial Assets	$188,346	$177,841

Holding_Company_Financial_Info2

Holding Company Financial Information - Condensed Balance Sheets (Detail) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
ASSETS	'	'	'	'	'	'	'	'	'
Cash and due from banks	$16,689	'	'	'	$57,641	'	'	'	'
Total cash and cash equivalents	423,216	461,197	512,573	507,665	518,493	546,397	667,509	691,205	'
Loans receivable (net of allowance for loan losses of $50)	1,099,689	'	'	'	1,079,363	'	'	'	'
Deferred income tax asset	18,362	'	'	'	29,234	'	'	'	'
Deferred debenture offering costs, net of amortization	700	'	'	'	800	'	'	'	'
All other assets	4,645	'	'	'	10,602	'	'	'	'
Total assets	1,567,796	1,584,239	1,596,639	1,627,787	1,665,792	1,751,880	1,862,110	1,909,052	'
LIABILITIES	'	'	'	'	'	'	'	'	'
All other liabilities	3,281	'	'	'	2,171	'	'	'	'
Total liabilities	1,370,805	'	'	'	1,454,845	'	'	'	'
STOCKHOLDERS' EQUITY	'	'	'	'	'	'	'	'	'
Common equity	21,919	'	'	'	21,590	'	'	'	'
Total stockholders' equity	196,991	192,288	211,775	215,265	210,947	207,108	204,121	201,051	197,531
Total liabilities and stockholders' equity	1,567,796	'	'	'	1,665,792	'	'	'	'
Parent Company [Member]	'	'	'	'	'	'	'	'	'
ASSETS	'	'	'	'	'	'	'	'	'
Cash and due from banks	319	'	'	'	46	'	'	'	'
Short-term investments	2,241	'	'	'	8,070	'	'	'	'
Total cash and cash equivalents	2,560	'	'	'	8,116	'	'	'	'
Loans receivable (net of allowance for loan losses of $50)	1,777	'	'	'	2,753	'	'	'	'
Investment in consolidated subsidiaries	240,918	'	'	'	254,815	'	'	'	'
Investment in unconsolidated subsidiaries - Intervest Statutory Trusts	1,702	'	'	'	1,702	'	'	'	'
Deferred income tax asset	6,800	'	'	'	5,748	'	'	'	'
Deferred debenture offering costs, net of amortization	742	'	'	'	779	'	'	'	'
All other assets	220	'	'	'	388	'	'	'	'
Total assets	254,719	'	'	'	274,301	'	'	'	'
LIABILITIES	'	'	'	'	'	'	'	'	'
Debentures payable - capital securities	56,702	'	'	'	56,702	'	'	'	'
Accrued interest payable on debentures	868	'	'	'	6,228	'	'	'	'
All other liabilities	158	'	'	'	424	'	'	'	'
Total liabilities	57,728	'	'	'	63,354	'	'	'	'
STOCKHOLDERS' EQUITY	'	'	'	'	'	'	'	'	'
Preferred equity, net of preferred stock discount	'	'	'	'	24,624	'	'	'	'
Common equity	196,991	'	'	'	186,323	'	'	'	'
Total stockholders' equity	196,991	'	'	'	210,947	'	'	'	'
Total liabilities and stockholders' equity	$254,719	'	'	'	$274,301	'	'	'	'

Holding_Company_Financial_Info3

Holding Company Financial Information - Condensed Balance Sheets (Parenthetical) (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Allowance for loan losses	$27,833	$28,103	$30,415	$34,840
Parent Company [Member]	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'
Allowance for loan losses	$50	$50	'	'

Holding_Company_Financial_Info4

Holding Company Financial Information - Condensed Statements of Earnings (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Interest expense	$6,023	$6,794	$7,048	$7,245	$8,103	$9,223	$10,001	$10,740	$27,110	$38,067	$50,540
Net interest and dividend income	10,097	8,830	8,575	9,004	9,695	9,859	9,705	9,958	36,506	39,217	42,297
Provision for loan losses	950	250	-750	-1,000	'	'	'	'	-550	'	5,018
Noninterest income	2,600	901	702	743	2,476	1,187	1,406	1,125	4,946	6,194	4,308
Noninterest expenses	'	'	'	'	'	'	'	'	15,853	22,882	20,829
Earnings before provision for income taxes	7,683	5,157	6,343	6,966	6,517	4,978	5,086	5,948	26,149	22,529	20,758
Credit for income taxes	3,476	2,300	2,804	3,075	2,987	2,300	2,326	2,694	11,655	10,307	9,512
Net earnings	4,207	2,857	3,539	3,891	3,530	2,678	2,760	3,254	14,494	12,222	11,246
Preferred stock dividend requirements and discount amortization	'	269	326	462	456	453	448	444	1,057	1,801	1,730
Consolidated net earnings available to common stockholders	4,207	2,588	3,213	3,429	3,074	2,225	2,312	2,810	13,437	10,421	9,516
Parent Company [Member]	'	'	'	'	'	'	'	'	'	'	'
Condensed Financial Statements, Captions [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Interest income	'	'	'	'	'	'	'	'	129	264	475
Interest expense	'	'	'	'	'	'	'	'	1,679	1,848	2,072
Net interest and dividend income	'	'	'	'	'	'	'	'	-1,550	-1,584	-1,597
Provision for loan losses	'	'	'	'	'	'	'	'	'	'	290
Noninterest income	'	'	'	'	'	'	'	'	5	5	8
Noninterest expenses	'	'	'	'	'	'	'	'	745	773	816
Earnings before provision for income taxes	'	'	'	'	'	'	'	'	-2,290	-2,352	-2,695
Credit for income taxes	'	'	'	'	'	'	'	'	1,052	1,080	1,237
Net loss before earnings of subsidiary	'	'	'	'	'	'	'	'	-1,238	-1,272	-1,458
Equity in undistributed earnings of Intervest National Bank	'	'	'	'	'	'	'	'	15,732	13,494	12,704
Net earnings	'	'	'	'	'	'	'	'	14,494	12,222	11,246
Preferred stock dividend requirements and discount amortization	'	'	'	'	'	'	'	'	1,057	1,801	1,730
Consolidated net earnings available to common stockholders	'	'	'	'	'	'	'	'	$13,437	$10,421	$9,516

Holding_Company_Financial_Info5

Holding Company Financial Information - Condensed Statements of Cash Flows (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
OPERATING ACTIVITIES	'	'	'
Net earnings	$14,494	$12,222	$11,246
Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:	'	'	'
(Decrease) increase in accrued interest payable on debentures	-5,360	1,867	2,099
Net change in all other assets and liabilities	8,507	3,506	17,244
Net cash provided by operating activities	30,602	37,171	46,117
INVESTING ACTIVITIES	'	'	'
Purchase of premises and equipment	-531	-119	-184
Net cash provided by investing activities	42,195	312,193	73,081
FINANCING ACTIVITIES	'	'	'
Net (decrease) increase in mortgage escrow funds payable	1,136	-1,927	-1,039
Redemption of preferred stock	-24,813	'	'
Cash dividends paid to preferred stockholders	-5,068	'	'
Proceeds from issuance of common stock upon exercise of options	61	'	'
Excess tax benefit from exercise of options and vesting of restricted stock	579	'	'
Net cash used in financing activities	-108,492	-318,832	-113,246
Net increase in cash and cash equivalents	-35,695	30,532	5,952
Cash and cash equivalents at beginning of year	60,395	29,863	23,911
Cash and cash equivalents at end of year	24,700	60,395	29,863
SUPPLEMENTAL DISCLOSURES	'	'	'
Cash paid for interest	33,304	37,503	49,342
Cash paid for (received from refunds of) income taxes, net	940	734	-10,340
Transfer of loans from subsidiary	3,040	4,689	4,375
Preferred dividend requirements and amortization of preferred stock discount	1,801	1,801	1,730
Parent Company [Member]	'	'	'
OPERATING ACTIVITIES	'	'	'
Net earnings	14,494	12,222	11,246
Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:	'	'	'
Equity in earnings of subsidiary	-15,732	-13,494	-12,704
Cash dividends from subsidiary	31,000	'	'
(Decrease) increase in accrued interest payable on debentures	-5,360	1,867	2,099
Net change in all other assets and liabilities	-1,460	-1,116	-926
Net cash provided by operating activities	22,942	-521	-285
INVESTING ACTIVITIES	'	'	'
Return of capital from subsidiary	'	'	229
Net decrease in loans receivable	981	45	3,884
Purchase of premises and equipment	-154	'	'
Net cash provided by investing activities	827	45	4,113
FINANCING ACTIVITIES	'	'	'
Net (decrease) increase in mortgage escrow funds payable	-84	44	-217
Redemption of preferred stock	-24,813	'	'
Cash dividends paid to preferred stockholders	-5,068	'	'
Proceeds from issuance of common stock upon exercise of options	61	'	'
Excess tax benefit from exercise of options and vesting of restricted stock	579	'	'
Net cash used in financing activities	-29,325	44	-217
Net increase in cash and cash equivalents	-5,556	-432	3,611
Cash and cash equivalents at beginning of year	8,116	8,548	4,937
Cash and cash equivalents at end of year	2,560	8,116	8,548
SUPPLEMENTAL DISCLOSURES	'	'	'
Cash paid for interest	7,002	'	'
Cash paid for (received from refunds of) income taxes, net	'	'	-43
Transfer of loans from subsidiary	'	'	7,437
Transfer of all other net assets from subsidiary	'	'	1,030
Subsidiary's compensation expense related to equity awards	823	1,194	326
Preferred dividend requirements and amortization of preferred stock discount	$1,057	$1,801	$1,730

Selected_Quarterly_Financial_D2

Selected Quarterly Financial Data - Interim Results of Operations and Other Period-End Selected Information by Quarter (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Interest and dividend income	$16,120	$15,624	$15,623	$16,249	$17,798	$19,082	$19,706	$20,698	$63,616	$77,284	$92,837
Interest expense	6,023	6,794	7,048	7,245	8,103	9,223	10,001	10,740	27,110	38,067	50,540
Net interest and dividend income	10,097	8,830	8,575	9,004	9,695	9,859	9,705	9,958	36,506	39,217	42,297
(Credit) provision for loan losses	950	250	-750	-1,000	'	'	'	'	-550	'	5,018
Net interest and dividend income after (credit) provision for loan losses	9,147	8,580	9,325	10,004	9,695	9,859	9,705	9,958	37,056	39,217	37,279
Noninterest income	2,600	901	702	743	2,476	1,187	1,406	1,125	4,946	6,194	4,308
Noninterest expenses:	'	'	'	'	'	'	'	'	'	'	'
Provision for real estate losses	150	250	76	629	1,135	1,025	1,397	511	'	'	'
Real estate expenses (income), net	284	212	-346	-986	'	'	'	'	'	'	'
Real estate expenses, net	'	'	'	'	324	883	479	460	-836	2,146	1,619
Operating expenses	3,630	3,862	3,954	4,138	4,195	4,160	4,149	4,164	'	'	'
Earnings before provision for income taxes	7,683	5,157	6,343	6,966	6,517	4,978	5,086	5,948	26,149	22,529	20,758
Provision for income taxes	3,476	2,300	2,804	3,075	2,987	2,300	2,326	2,694	11,655	10,307	9,512
Net earnings	4,207	2,857	3,539	3,891	3,530	2,678	2,760	3,254	14,494	12,222	11,246
Preferred dividend requirements and discount amortization	'	269	326	462	456	453	448	444	1,057	1,801	1,730
Net earnings available to common stockholders	4,207	2,588	3,213	3,429	3,074	2,225	2,312	2,810	13,437	10,421	9,516
Basic earnings per common share	$0.19	$0.12	$0.14	$0.16	$0.14	$0.10	$0.11	$0.13	$0.61	$0.48	$0.45
Diluted earnings per common share	$0.19	$0.12	$0.14	$0.16	$0.14	$0.10	$0.11	$0.13	$0.61	$0.48	$0.45
Cash dividends paid per common share	'	'	'	'	'	'	'	'	'	'	'
Total assets	1,567,796	1,584,239	1,596,639	1,627,787	1,665,792	1,751,880	1,862,110	1,909,052	1,567,796	1,665,792	'
Total cash, short-term investments and security investments	423,216	461,197	512,573	507,665	518,493	546,397	667,509	691,205	423,216	518,493	'
Total loans, net of unearned fees	1,127,522	1,100,277	1,056,191	1,081,482	1,107,466	1,155,171	1,137,780	1,155,437	1,127,522	1,107,466	'
Total deposits	1,282,232	1,298,403	1,293,175	1,318,215	1,362,619	1,432,209	1,554,615	1,599,653	1,282,232	1,362,619	'
Total borrowed funds and related accrued interest payable	57,570	57,165	56,760	63,373	62,930	69,487	72,528	72,064	57,570	62,930	'
Total stockholders' equity	$196,991	$192,288	$211,775	$215,265	$210,947	$207,108	$204,121	$201,051	$196,991	$210,947	$197,531