2.4.0.82406408 - Disclosure - Loans and Allowance for Loan Losses - Additional Information (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$I2013Q2http://www.sec.gov/CIK0000737210instant2013-06-30T00:00:000001-01-01T00:00:00numberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false falsefalseI2012Q4http://www.sec.gov/CIK0000737210instant2012-12-31T00:00:000001-01-01T00:00:00numberStandardhttp://www.xbrl.org/2003/instancepurexbrli03false truefalseD2013Q2YTD_us-gaap_RangeAxis_us-gaap_MaximumMemberhttp://www.sec.gov/CIK0000737210duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMember4false truefalseD2013Q2YTD_us-gaap_RangeAxis_us-gaap_MinimumMemberhttp://www.sec.gov/CIK0000737210duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMember1true 3us-gaap_AccountsNotesAndLoansReceivableLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Accounts, Notes, Loans and Financing Receivable [Line Items]2false 4lnbb_BankWideDelinquencyOfLoansPercentagelnbb_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.02150.0215falsefalsefalse2truetruefalse0.02890.0289falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalsenum:percentItemTypepureBank wide delinquency of loans in percentage.No definition available.false0Bank wide delinquency of loans in percentage3false 4lnbb_BankWideDelinquencyOfLoans30To59DaysDelinquentPercentagelnbb_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.00190.0019falsefalsefalse2truetruefalse0.00610.0061falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalsenum:percentItemTypepureBank Wide Delinquency of Loans, 30 to 59 Days Delinquent, PercentageNo definition available.false0Bank wide delinquency of loans, 30 to 59 days delinquent, percentage4false 4lnbb_BankWideDelinquencyOfLoans60To89DaysDelinquentPercentagelnbb_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.00230.0023falsefalsefalse2truetruefalse0.00320.0032falsefalsefalse3falsetruefalse00falsefalsefalse4falsetruefalse00falsefalsefalsenum:percentItemTypepureBank Wide Delinquency of Loans, 60 to 89 Days Delinquent, PercentageNo definition available.false0Bank wide delinquency of loans, 60 to 89 days delinquent, percentage5false 4lnbb_AllocatedReservesOfNonaccrualTroubledDebtRestructuringLoanslnbb_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse384000384USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAllocated reserves of nonaccrual TDR loans.No definition available.false2Allocated reserves of nonaccrual TDR loans6false 4us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLendus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse638000638USD$falsetruefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6951948&loc=d3e18794-111554 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 15 -Paragraph 40 -Subparagraph b. -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Additional commitments to lend7false 4lnbb_DelinquencyPeriodOnelnbb_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse0059 daysfalsefalsefalse4falsefalsefalse0030 daysfalsefalsefalsexbrli:durationItemTypenaDelinquency period one.No definition available.false0Time period of repayment based on delinquency period one8false 4lnbb_DelinquencyPeriodTwolnbb_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse0089 daysfalsefalsefalse4falsefalsefalse0060 daysfalsefalsefalsexbrli:durationItemTypenaDelinquency period two.No definition available.false0Time period of repayment based on delinquency period two9false 4lnbb_DelinquencyPeriodThreelnbb_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse0090 daysfalsefalsefalsexbrli:durationItemTypenaDelinquency period three.No definition available.false0Time period of repayment based on delinquency period threefalseLoans and Allowance for Loan Losses - Additional Information (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.4lnb.com/role/LoansAndAllowanceForLoanLossesAdditionalInformationDetails49