3.22.2.2 html 274 396 1 false 64 0 false 7 false false R1.htm 00090 - Document - Document and Entity Information Sheet http://www.johnmarshallbank.com/role/DocumentDocumentAndEntityInformation Document and Entity Information Cover 1 false false R2.htm 00100 - Statement - Consolidated Balance Sheets Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedBalanceSheets Consolidated Balance Sheets Statements 2 false false R3.htm 00105 - Statement - Consolidated Balance Sheets (Parenthetical) Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedBalanceSheetsParenthetical Consolidated Balance Sheets (Parenthetical) Statements 3 false false R4.htm 00200 - Statement - Consolidated Statements of Income Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfIncome Consolidated Statements of Income Statements 4 false false R5.htm 00300 - Statement - Consolidated Statements of Comprehensive Income (Loss) Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfComprehensiveIncomeLoss Consolidated Statements of Comprehensive Income (Loss) Statements 5 false false R6.htm 00305 - Statement - Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfComprehensiveIncomeLossParenthetical Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) Statements 6 false false R7.htm 00400 - Statement - Consolidated Statements of Shareholders' Equity Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfShareholdersEquity Consolidated Statements of Shareholders' Equity Statements 7 false false R8.htm 00405 - Statement - Consolidated Statements of Shareholders' Equity (Parenthetical) Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfShareholdersEquityParenthetical Consolidated Statements of Shareholders' Equity (Parenthetical) Statements 8 false false R9.htm 00500 - Statement - Consolidated Statements of Cash Flows Sheet http://www.johnmarshallbank.com/role/StatementConsolidatedStatementsOfCashFlows Consolidated Statements of Cash Flows Statements 9 false false R10.htm 10101 - Disclosure - Nature of Business and Summary of Significant Accounting Policies Sheet http://www.johnmarshallbank.com/role/DisclosureNatureOfBusinessAndSummaryOfSignificantAccountingPolicies Nature of Business and Summary of Significant Accounting Policies Notes 10 false false R11.htm 10201 - Disclosure - Investment Securities Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecurities Investment Securities Notes 11 false false R12.htm 10301 - Disclosure - Loans Sheet http://www.johnmarshallbank.com/role/DisclosureLoans Loans Notes 12 false false R13.htm 10401 - Disclosure - Allowance for Loan Losses Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLosses Allowance for Loan Losses Notes 13 false false R14.htm 10501 - Disclosure - Deposits and Borrowings Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowings Deposits and Borrowings Notes 14 false false R15.htm 10601 - Disclosure - Income Taxes Sheet http://www.johnmarshallbank.com/role/DisclosureIncomeTaxes Income Taxes Notes 15 false false R16.htm 10701 - Disclosure - Commitments and Contingencies Sheet http://www.johnmarshallbank.com/role/DisclosureCommitmentsAndContingencies Commitments and Contingencies Notes 16 false false R17.htm 10801 - Disclosure - Fair Value Measurements Sheet http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurements Fair Value Measurements Notes 17 false false R18.htm 10901 - Disclosure - Earnings per Common Share Sheet http://www.johnmarshallbank.com/role/DisclosureEarningsPerCommonShare Earnings per Common Share Notes 18 false false R19.htm 11001 - Disclosure - Stock Based Compensation Plan Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlan Stock Based Compensation Plan Notes 19 false false R20.htm 11101 - Disclosure - Regulatory Capital Sheet http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapital Regulatory Capital Notes 20 false false R21.htm 11201 - Disclosure - Revenue Sheet http://www.johnmarshallbank.com/role/DisclosureRevenue Revenue Notes 21 false false R22.htm 11301 - Disclosure - Other Operating Expenses Sheet http://www.johnmarshallbank.com/role/DisclosureOtherOperatingExpenses Other Operating Expenses Notes 22 false false R23.htm 11401 - Disclosure - Accumulated Other Comprehensive Income (Loss) Sheet http://www.johnmarshallbank.com/role/DisclosureAccumulatedOtherComprehensiveIncomeLoss Accumulated Other Comprehensive Income (Loss) Notes 23 false false R24.htm 20102 - Disclosure - Nature of Business and Summary of Significant Accounting Policies (Policies) Sheet http://www.johnmarshallbank.com/role/DisclosureNatureOfBusinessAndSummaryOfSignificantAccountingPoliciesPolicies Nature of Business and Summary of Significant Accounting Policies (Policies) Policies http://www.johnmarshallbank.com/role/DisclosureNatureOfBusinessAndSummaryOfSignificantAccountingPolicies 24 false false R25.htm 30203 - Disclosure - Investment Securities (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesTables Investment Securities (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureInvestmentSecurities 25 false false R26.htm 30303 - Disclosure - Loans (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureLoansTables Loans (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureLoans 26 false false R27.htm 30403 - Disclosure - Allowance for Loan Losses (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesTables Allowance for Loan Losses (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLosses 27 false false R28.htm 30503 - Disclosure - Deposits and Borrowings (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowingsTables Deposits and Borrowings (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowings 28 false false R29.htm 30603 - Disclosure - Income Taxes (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureIncomeTaxesTables Income Taxes (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureIncomeTaxes 29 false false R30.htm 30703 - Disclosure - Commitments and Contingencies (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureCommitmentsAndContingenciesTables Commitments and Contingencies (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureCommitmentsAndContingencies 30 false false R31.htm 30803 - Disclosure - Fair Value Measurements (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurementsTables Fair Value Measurements (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurements 31 false false R32.htm 30903 - Disclosure - Earnings per Common Share (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureEarningsPerCommonShareTables Earnings per Common Share (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureEarningsPerCommonShare 32 false false R33.htm 31003 - Disclosure - Stock Based Compensation Plan (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanTables Stock Based Compensation Plan (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlan 33 false false R34.htm 31103 - Disclosure - Regulatory Capital (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapitalTables Regulatory Capital (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapital 34 false false R35.htm 31203 - Disclosure - Revenue (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureRevenueTables Revenue (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureRevenue 35 false false R36.htm 31303 - Disclosure - Other Operating Expenses (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureOtherOperatingExpensesTables Other Operating Expenses (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureOtherOperatingExpenses 36 false false R37.htm 31403 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) Sheet http://www.johnmarshallbank.com/role/DisclosureAccumulatedOtherComprehensiveIncomeLossTables Accumulated Other Comprehensive Income (Loss) (Tables) Tables http://www.johnmarshallbank.com/role/DisclosureAccumulatedOtherComprehensiveIncomeLoss 37 false false R38.htm 40201 - Disclosure - Investment Securities - Amortized cost and fair value of securities held-to-maturity and available-for-sale (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesAmortizedCostAndFairValueOfSecuritiesHeldToMaturityAndAvailableForSaleDetails Investment Securities - Amortized cost and fair value of securities held-to-maturity and available-for-sale (Details) Details 38 false false R39.htm 40202 - Disclosure - Investment Securities - Fair value of securities held-to-maturity and available-for-sale (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesFairValueOfSecuritiesHeldToMaturityAndAvailableForSaleDetails Investment Securities - Fair value of securities held-to-maturity and available-for-sale (Details) Details 39 false false R40.htm 40203 - Disclosure - Investment Securities - Contractual maturities of investment securities (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesContractualMaturitiesOfInvestmentSecuritiesDetails Investment Securities - Contractual maturities of investment securities (Details) Details 40 false false R41.htm 40204 - Disclosure - Investment Securities - Carrying amount of restricted securities (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesCarryingAmountOfRestrictedSecuritiesDetails Investment Securities - Carrying amount of restricted securities (Details) Details 41 false false R42.htm 40205 - Disclosure - Investment Securities - Additional information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureInvestmentSecuritiesAdditionalInformationDetails Investment Securities - Additional information (Details) Details 42 false false R43.htm 40301 - Disclosure - Loans (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureLoansDetails Loans (Details) Details http://www.johnmarshallbank.com/role/DisclosureLoansTables 43 false false R44.htm 40401 - Disclosure - Allowance for Loan Losses - Additional information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesAdditionalInformationDetails Allowance for Loan Losses - Additional information (Details) Details 44 false false R45.htm 40402 - Disclosure - Allowance for Loan Losses - Allowance for loan losses activity (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesAllowanceForLoanLossesActivityDetails Allowance for Loan Losses - Allowance for loan losses activity (Details) Details 45 false false R46.htm 40403 - Disclosure - Allowance for Loan Losses - Balance of allowance for loan losses (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesBalanceOfAllowanceForLoanLossesDetails Allowance for Loan Losses - Balance of allowance for loan losses (Details) Details 46 false false R47.htm 40404 - Disclosure - Allowance for Loan Losses - Impaired loans (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesImpairedLoansDetails Allowance for Loan Losses - Impaired loans (Details) Details 47 false false R48.htm 40405 - Disclosure - Allowance for Loan Losses - Past due and non-accrual loans (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesPastDueAndNonAccrualLoansDetails Allowance for Loan Losses - Past due and non-accrual loans (Details) Details 48 false false R49.htm 40406 - Disclosure - Allowance for Loan Losses - Schedule of credit quality information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAllowanceForLoanLossesScheduleOfCreditQualityInformationDetails Allowance for Loan Losses - Schedule of credit quality information (Details) Details 49 false false R50.htm 40501 - Disclosure - Deposits and Borrowings - Deposits (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowingsDepositsDetails Deposits and Borrowings - Deposits (Details) Details 50 false false R51.htm 40502 - Disclosure - Deposits and Borrowings - Long-term Debt (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowingsLongTermDebtDetails Deposits and Borrowings - Long-term Debt (Details) Details 51 false false R52.htm 40503 - Disclosure - Deposits and Borrowings - Additional Information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowingsAdditionalInformationDetails Deposits and Borrowings - Additional Information (Details) Details 52 false false R53.htm 40504 - Disclosure - Deposits and Borrowings - Time deposits and FHLB advances by contractual maturity (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureDepositsAndBorrowingsTimeDepositsAndFhlbAdvancesByContractualMaturityDetails Deposits and Borrowings - Time deposits and FHLB advances by contractual maturity (Details) Details 53 false false R54.htm 40601 - Disclosure - Income Taxes - Provision for income taxes (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureIncomeTaxesProvisionForIncomeTaxesDetails Income Taxes - Provision for income taxes (Details) Details 54 false false R55.htm 40602 - Disclosure - Income Taxes - Income tax rate reconciliation (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureIncomeTaxesIncomeTaxRateReconciliationDetails Income Taxes - Income tax rate reconciliation (Details) Details 55 false false R56.htm 40701 - Disclosure - Commitments and Contingencies (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureCommitmentsAndContingenciesDetails Commitments and Contingencies (Details) Details http://www.johnmarshallbank.com/role/DisclosureCommitmentsAndContingenciesTables 56 false false R57.htm 40801 - Disclosure - Fair Value Measurements - Fair value of assets measured at fair value on a recurring basis (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurementsFairValueOfAssetsMeasuredAtFairValueOnRecurringBasisDetails Fair Value Measurements - Fair value of assets measured at fair value on a recurring basis (Details) Details 57 false false R58.htm 40802 - Disclosure - Fair Value Measurements - Carrying value and estimated fair value of financial instruments (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurementsCarryingValueAndEstimatedFairValueOfFinancialInstrumentsDetails Fair Value Measurements - Carrying value and estimated fair value of financial instruments (Details) Details 58 false false R59.htm 40803 - Disclosure - Fair Value Measurements - Additional information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureFairValueMeasurementsAdditionalInformationDetails Fair Value Measurements - Additional information (Details) Details 59 false false R60.htm 40901 - Disclosure - Earnings per Common Share - Computation of earnings per share (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureEarningsPerCommonShareComputationOfEarningsPerShareDetails Earnings per Common Share - Computation of earnings per share (Details) Details 60 false false R61.htm 40902 - Disclosure - Earnings per Common Share - Additional information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureEarningsPerCommonShareAdditionalInformationDetails Earnings per Common Share - Additional information (Details) Details 61 false false R62.htm 41001 - Disclosure - Stock Based Compensation Plan (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanDetails Stock Based Compensation Plan (Details) Details http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanTables 62 false false R63.htm 41002 - Disclosure - Stock Based Compensation Plan - Summary of Stock Options Activity (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanSummaryOfStockOptionsActivityDetails Stock Based Compensation Plan - Summary of Stock Options Activity (Details) Details 63 false false R64.htm 41003 - Disclosure - Stock Based Compensation Plan - Summary of Stock Options Outstanding and Exercisable (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanSummaryOfStockOptionsOutstandingAndExercisableDetails Stock Based Compensation Plan - Summary of Stock Options Outstanding and Exercisable (Details) Details 64 false false R65.htm 41004 - Disclosure - Stock Based Compensation Plan - Summary of Restricted Stock Awards (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureStockBasedCompensationPlanSummaryOfRestrictedStockAwardsDetails Stock Based Compensation Plan - Summary of Restricted Stock Awards (Details) Details 65 false false R66.htm 41101 - Disclosure - Regulatory Capital (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapitalDetails Regulatory Capital (Details) Details http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapitalTables 66 false false R67.htm 41102 - Disclosure - Regulatory Capital - Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureRegulatoryCapitalScheduleOfComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsDetails Regulatory Capital - Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations (Details) Details 67 false false R68.htm 41201 - Disclosure - Revenue - Components of Non-interest Income (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureRevenueComponentsOfNonInterestIncomeDetails Revenue - Components of Non-interest Income (Details) Details 68 false false R69.htm 41202 - Disclosure - Revenue - Additional information (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureRevenueAdditionalInformationDetails Revenue - Additional information (Details) Details 69 false false R70.htm 41301 - Disclosure - Other Operating Expenses (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureOtherOperatingExpensesDetails Other Operating Expenses (Details) Details http://www.johnmarshallbank.com/role/DisclosureOtherOperatingExpensesTables 70 false false R71.htm 41401 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Details) Sheet http://www.johnmarshallbank.com/role/DisclosureAccumulatedOtherComprehensiveIncomeLossDetails Accumulated Other Comprehensive Income (Loss) (Details) Details http://www.johnmarshallbank.com/role/DisclosureAccumulatedOtherComprehensiveIncomeLossTables 71 false false All Reports Book All Reports [dq-0542-Deprecated-Concept] Concept PledgedAssetsSeparatelyReportedSecuritiesPledgedAsCollateralAtFairValue in us-gaap/2021 used in 2 facts was deprecated in us-gaap/2022 as of 2022 and should not be used. jmsb-20220930x10q.htm 20 [dq-0542-Deprecated-Concept] Concept LoansPledgedAsCollateral in us-gaap/2021 used in 1 facts was deprecated in us-gaap/2022 as of 2022 and should not be used. jmsb-20220930x10q.htm 27 [ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 3 fact(s) appearing in ix:hidden were eligible for transformation: us-gaap:CommonStockSharesOutstanding, us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1 - jmsb-20220930x10q.htm 9 [ix-0514-Hidden-Fact-Not-Referenced] WARN: 2 fact(s) appearing in ix:hidden were not referenced by any -sec-ix-hidden style property: us-gaap:CommitmentsAndContingencies - jmsb-20220930x10q.htm 9 jmsb-20220930x10q.htm jmsb-20220930.xsd jmsb-20220930_cal.xml jmsb-20220930_def.xml jmsb-20220930_lab.xml jmsb-20220930_pre.xml jmsb-20220930xex31d1.htm jmsb-20220930xex31d2.htm jmsb-20220930xex32d1.htm jmsb-20220930xex4d2.htm http://fasb.org/us-gaap/2021-01-31 http://xbrl.sec.gov/dei/2021q4 true true