$MBWM
Mercantile Bank Corp Stock $mbwm

$mbwm Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000143774921005133 Filed on March 05, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020 Q2
Revenue	$37.62M	$35.59M	$37.16M
YoY Change	-4.91%	-11.71%	-6.67%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$3.170M	$1.300M	$1.300M
YoY Change	24.31%	44.44%	44.44%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$6.085M	$6.593M
YoY Change		-30.15%	-24.24%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$17.74M	$13.19M	$10.74M
YoY Change	11.92%	-15.18%	-25.75%
Income Tax	$3.660M	$2.507M	$2.041M
% Of Pretax Income	20.63%	19.0%	19.01%
Net Earnings	$14.08M	$10.69M	$8.697M
YoY Change	5.74%	-15.19%	-25.76%
Net Earnings / Revenue	37.43%	30.02%	23.4%
Basic Earnings Per Share	$0.86	$0.66	$0.54
Diluted Earnings Per Share	$0.86	$0.66	$0.54
COMMON SHARES
Basic Shares Outstanding	16.23M	16.23M	16.21M
Diluted Shares Outstanding		16.23M	16.21M

Balance Sheet

Concept	2020 Q4	2020 Q3	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$626.0M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$58.96M	$60.45M	$59.16M
YoY Change	2.85%	10.74%	14.15%
Goodwill	$49.47M	$49.47M	$49.47M
YoY Change	0.0%	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$4.437B	$4.421B	$4.314B
YoY Change	22.14%	19.14%	20.64%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$24.30M	$18.30M	$18.10M
YoY Change	8.48%	-14.49%	9.04%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$118.4M	$157.0M	$167.5M
YoY Change	15.29%	50.96%	39.93%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$24.30M	$18.30M	$18.10M
YoY Change	8.48%	-14.49%	9.04%
LONG-TERM LIABILITIES
Long-Term Debt	$47.60M	$47.40M	$47.20M
YoY Change	1.49%	1.5%	1.51%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$47.60M	$47.40M	$47.20M
YoY Change	1.49%	1.5%	1.51%
TOTAL LIABILITIES
Total Short-Term Liabilities	$24.30M	$18.30M	$18.10M
Total Long-Term Liabilities	$47.60M	$47.40M	$47.20M
Total Liabilities	$3.996B	$3.989B	$3.889B
YoY Change	24.23%	20.75%	22.45%
SHAREHOLDERS EQUITY
Retained Earnings	$134.0M	$124.5M	$118.2M
YoY Change	24.3%	25.87%	30.48%
Common Stock	$302.0M	$301.9M	$300.9M
YoY Change	-0.99%	-0.71%	-1.88%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$441.6M	$431.9M	$425.2M
YoY Change
Total Liabilities & Shareholders Equity	$4.437B	$4.421B	$4.314B
YoY Change	22.14%	19.14%	20.64%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020 Q2
OPERATING ACTIVITIES
Net Income	$14.08M	$10.69M	$8.697M
YoY Change	5.74%	-15.19%	-25.76%
Depreciation, Depletion And Amortization	$3.170M	$1.300M	$1.300M
YoY Change	24.31%	44.44%	44.44%
Cash From Operating Activities	$21.57M	$28.70M	-$2.610M
YoY Change	-12.46%	362.16%	-122.76%
INVESTING ACTIVITIES
Capital Expenditures	-$1.790M	-$2.770M	-$1.270M
YoY Change	-59.04%	-26.13%	-51.71%
Acquisitions
YoY Change
Other Investing Activities	$55.35M	-$37.55M	-$408.5M
YoY Change	-28.19%	-3.45%	437.56%
Cash From Investing Activities	$53.56M	-$40.32M	-$409.8M
YoY Change	-26.33%	-5.44%	421.19%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-3.720M	94.99M	646.9M
YoY Change	-95.96%	-17.07%	24127.34%
NET CHANGE
Cash From Operating Activities	21.57M	28.70M	-2.610M
Cash From Investing Activities	53.56M	-40.32M	-409.8M
Cash From Financing Activities	-3.720M	94.99M	646.9M
Net Change In Cash	71.41M	83.37M	234.5M
YoY Change	1273.27%	6.73%	-463.68%
FREE CASH FLOW
Cash From Operating Activities	$21.57M	$28.70M	-$2.610M
Capital Expenditures	-$1.790M	-$2.770M	-$1.270M
Free Cash Flow	$23.36M	$31.47M	-$1.340M
YoY Change	-19.48%	215.96%	-109.5%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2018	us-gaap	Other Noninterest Expense OtherNoninterestExpense	14944000	USD
CY2020	us-gaap	Noninterest Expense NoninterestExpense	98520000	USD
CY2019	us-gaap	Noninterest Expense NoninterestExpense	89280000	USD
CY2018	us-gaap	Noninterest Expense NoninterestExpense	86170000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	54848000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	60460000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	51822000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11004000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9798000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.01
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.53
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.71
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.01
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.53
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	2268000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	15106000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.71
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-4225000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	0	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	0	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax	2000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	2268000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	15106000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax Portion Attributable To Parent OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent	-4223000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	477000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	3172000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-846000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-0	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-0	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	1000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	477000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	3172000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax Portion Attributable To Parent1 OtherComprehensiveIncomeLossTaxPortionAttributableToParent1	-845000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1791000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	11934000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-3378000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	45929000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	61390000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	38646000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	365870000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	52000	USD
CY2018	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	1165000	USD
CY2018	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	108000	USD
CY2018	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	441000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2410000	USD
CY2018	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	5943000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	27500000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-3379000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	1000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	375249000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	375249000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	50000	USD
CY2019	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	729000	USD
CY2019	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	128000	USD
CY2019	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	375000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2931000	USD
CY2019	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	7183000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	17108000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	11934000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	416561000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	416561000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	49000	USD
CY2020	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	814000	USD
CY2020	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	3000	USD
CY2020	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	394000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2325000	USD
CY2020	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6591000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	17930000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	1791000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	441554000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	9425000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	9553000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	9766000	USD
CY2020	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	449000	USD
CY2019	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	686000	USD
CY2018	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	1373000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	14050000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1750000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1100000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-4141000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	26000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-372000	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	2325000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	2931000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	2410000	USD
CY2020	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	394000	USD
CY2019	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	375000	USD
CY2018	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	441000	USD
CY2020	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	677634000	USD
CY2019	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	261021000	USD
CY2018	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	101146000	USD
CY2020	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	665992000	USD
CY2019	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	256767000	USD
CY2018	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	96179000	USD
CY2020	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	29541000	USD
CY2019	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	8108000	USD
CY2018	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	3536000	USD
CY2020	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	325000	USD
CY2019	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	254000	USD
CY2018	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	169000	USD
CY2020	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	27000	USD
CY2019	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	436000	USD
CY2018	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	78000	USD
CY2020	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-1514000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-294000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-134000	USD
CY2020	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1214000	USD
CY2019	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	3886000	USD
CY2018	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	1287000	USD
CY2020	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	369682000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	62084000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	48664000	USD
CY2020	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	321164000	USD
CY2020	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	917000	USD
CY2019	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	48000	USD
CY2018	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	1126000	USD
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	10892000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	7636000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	2193000	USD
CY2020	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	1895000	USD
CY2019	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-2818000	USD
CY2018	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	11029000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	37877000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	44767000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	61737000	USD
CY2019	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	79478000	USD
CY2018	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	40308000	USD
CY2020	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	-0	USD
CY2019	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	1980000	USD
CY2018	us-gaap	Payments To Acquire Federal Home Loan Bank Stock PaymentsToAcquireFederalHomeLoanBankStock	4986000	USD
CY2020	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	341461000	USD
CY2019	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	99620000	USD
CY2018	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	193556000	USD
CY2020	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	700000	USD
CY2019	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	4500000	USD
CY2018	us-gaap	Payments To Acquire Life Insurance Policies PaymentsToAcquireLifeInsurancePolicies	-0	USD
CY2020	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2019	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	7708000	USD
CY2018	us-gaap	Proceeds From Life Insurance Policies ProceedsFromLifeInsurancePolicies	0	USD
CY2020	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	8989000	USD
CY2019	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	13484000	USD
CY2018	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	6318000	USD
CY2020	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	162000	USD
CY2019	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	854000	USD
CY2018	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	1964000	USD
CY2020	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	700000	USD
CY2019	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	790000	USD
CY2018	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	772000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-398806000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-92838000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-210480000	USD
CY2020	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-99294000	USD
CY2019	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	170921000	USD
CY2018	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-30091000	USD
CY2020	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	820463000	USD
CY2019	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	55755000	USD
CY2018	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	-28566000	USD
CY2020	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	15690000	USD
CY2019	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-844000	USD
CY2018	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	-15229000	USD
CY2020	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	60000000	USD
CY2019	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	44000000	USD
CY2018	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	160000000	USD
CY2020	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	20000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	27500000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	753204000	USD
CY2019	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	40000000	USD
CY2018	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	30000000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	3000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	128000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	108000	USD
CY2020	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	49000	USD
CY2019	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	50000	USD
CY2018	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	52000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	814000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	729000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	1165000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	6591000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	7183000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	5943000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	17930000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	17108000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	206448000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	23996000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	392275000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	158377000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-124747000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	233731000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	75354000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	200101000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	626006000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	233731000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	75354000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	27703000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	32103000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	21569000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	10950000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	11975000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	10075000	USD
CY2020	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	146000	USD
CY2019	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	337000	USD
CY2018	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	744000	USD
CY2020	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	613000	USD
CY2019	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	258000	USD
CY2018	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	296000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<span style="text-decoration: underline; ">Use of Estimates</span>: To prepare financial statements in conformity with accounting principles generally accepted in the United States of America, management makes estimates and assumptions based on available information. These estimates and assumptions affect the amounts reported in the financial statements and the disclosures provided, and actual results could differ. The allowance for loan losses and the fair values of financial instruments are particularly subject to change.
CY2020Q2	mbwm	Financing Receivable Advances Under Paycheck Protection Program Liquidity Facility FinancingReceivableAdvancesUnderPaycheckProtectionProgramLiquidityFacility	43700000	USD
CY2020Q4	mbwm	Financing Receivable Advances Under Paycheck Protection Program Liquidity Facility FinancingReceivableAdvancesUnderPaycheckProtectionProgramLiquidityFacility	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	4400000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Deferred Income LoansAndLeasesReceivableDeferredIncome	500000	USD
CY2020	mbwm	Interest Income On Commercial And Mortgage Loans Discontinued Period InterestIncomeOnCommercialAndMortgageLoansDiscontinuedPeriod	P90D
CY2020	mbwm	Maximum Delinquency Period For Consumer And Credit Card Loans To Be Charged Off MaximumDelinquencyPeriodForConsumerAndCreditCardLoansToBeChargedOff	P120D
CY2020Q4	us-gaap	Foreclosed Assets ForeclosedAssets	700000	USD
CY2019Q4	us-gaap	Foreclosed Assets ForeclosedAssets	500000	USD
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<span style="text-decoration: underline; ">Reclassifications</span>: Certain items in the prior years’ financial statements have been reclassified to conform to the current year presentation.
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	380403000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	7843000	USD
CY2020Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	899000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	387347000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	329979000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	5930000	USD
CY2019Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1254000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	334655000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	119073000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	899000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	0	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	119073000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	899000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	32243000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	395000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	85330000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	859000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	117573000	USD
CY2019Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	1254000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	64	pure
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	119000000	USD
CY2020Q4	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	900000	USD
CY2020Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	0	USD
CY2019Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	14622000	USD
CY2019Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	2842045000	USD
CY2020Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due In One Year Or Less WeightedAverageYieldOfSecuritiesPortfolioDueInOneYearOrLess	0.0252	pure
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost	5906000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	5939000	USD
CY2020Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due From One To Five Years WeightedAverageYieldOfSecuritiesPortfolioDueFromOneToFiveYears	0.0116	pure
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost	93320000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After One Through Five Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue	94474000	USD
CY2020Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due From Five To Ten Years WeightedAverageYieldOfSecuritiesPortfolioDueFromFiveToTenYears	0.0167	pure
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	176848000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	180541000	USD
CY2020Q4	mbwm	Weighted Average Yield Of Securities Portfolio Due Afterten Years WeightedAverageYieldOfSecuritiesPortfolioDueAftertenYears	0.0207	pure
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	79960000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	81003000	USD
CY2020Q4	mbwm	Weighted Average Yield Of Securities Portfolio WeightedAverageYieldOfSecuritiesPortfolio	0.0167	pure
CY2020Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	380403000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	387347000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3216358000	USD
CY2020Q4	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2856667000	USD
CY2019Q4	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
CY2020	mbwm	Loans And Leases Receivable Net Of Deferred Income Increase Decrease Percentage LoansAndLeasesReceivableNetOfDeferredIncomeIncreaseDecreasePercentage	0.126	pure
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	3041000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	3213317000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3216358000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Past Due FinancingReceivableRecordedInvestmentPastDue	1884000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment Current FinancingReceivableRecordedInvestmentCurrent	2854783000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2856667000	USD
CY2019Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	26892000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	24738000	USD
CY2020	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	17315000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	2266000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	2220000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	551000	USD
CY2020	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	2742000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	29158000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	26958000	USD
CY2020Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	551000	USD
CY2020	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	20057000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	13687000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	12245000	USD
CY2019	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	16675000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	2398000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	2377000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	1623000	USD
CY2019	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	8833000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	16085000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	14622000	USD
CY2019Q4	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	1623000	USD
CY2019	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	25508000	USD
CY2020	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1300000	USD
CY2018	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1100000	USD
CY2020	mbwm	Loans And Leases Receivable Nonaccrual Loans Interest Income Recognized LoansAndLeasesReceivableNonaccrualLoansInterestIncomeRecognized	100000	USD
CY2020	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	200000	USD
CY2019	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	100000	USD
CY2018	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	300000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	23889000	USD
CY2020	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	14050000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	838000	USD
CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	866000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37967000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	551000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	37416000	USD
CY2020Q4	mbwm	Loans And Leases Receivable Net Of Deferred Income Excluding Ppp Loans LoansAndLeasesReceivableNetOfDeferredIncomeExcludingPPPLoans	2851099000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	26958000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	2824141000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	22380000	USD
CY2019	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1750000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	883000	USD
CY2019	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	642000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	23889000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	1689000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	22200000	USD
CY2019Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2856667000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	57327000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	3400000	USD
CY2020	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	45	pure
CY2020	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	22498000	USD
CY2020	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	23298000	USD
CY2017Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	19501000	USD
CY2018	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1100000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	1450000	USD
CY2018	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	3229000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	22380000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	1089000	USD
CY2018Q4	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	21291000	USD
CY2018Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	2753085000	USD
CY2018Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	23908000	USD
CY2018Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	2729177000	USD
CY2019	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	36	pure
CY2019	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	2796000	USD
CY2019	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	2797000	USD
CY2020	mbwm	Minimum Number Of Days Past Due At Period End For Loans Modified As Troubled Debt Restructurings MinimumNumberOfDaysPastDueAtPeriodEndForLoansModifiedAsTroubledDebtRestructurings	P30D
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	pure
CY2020	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	3	pure
CY2019	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	126000	USD
CY2020Q4	mbwm	Allowance For Credit Losses Troubled Debt Restructuring AllowanceForCreditLossesTroubledDebtRestructuring	467000	USD
CY2019Q4	mbwm	Allowance For Credit Losses Troubled Debt Restructuring AllowanceForCreditLossesTroubledDebtRestructuring	1578000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	94169000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	92598000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	35210000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	35271000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	58959000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	600000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two And Three Years OperatingLeasesFutureMinimumPaymentsDueInTwoAndThreeYears	1200000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four And Five Years OperatingLeasesFutureMinimumPaymentsDueInFourAndFiveYears	500000	USD
CY2020Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	1100000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	3800000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	600000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two And Three Years OperatingLeasesFutureMinimumPaymentsDueInTwoAndThreeYears	1100000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four And Five Years OperatingLeasesFutureMinimumPaymentsDueInFourAndFiveYears	900000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	1200000	USD
CY2020	us-gaap	Depreciation Depreciation	5200000	USD
CY2019	us-gaap	Depreciation Depreciation	3900000	USD
CY2018	us-gaap	Depreciation Depreciation	3600000	USD
CY2020Q4	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	1038928000	USD
CY2019Q4	us-gaap	Continuing Involvement With Transferred Financial Assets Principal Amount Outstanding ContinuingInvolvementWithTransferredFinancialAssetsPrincipalAmountOutstanding	726960000	USD
CY2020Q4	mbwm	Continuing Involvement With Transferred Financial Assets Custodial Escrow Balance ContinuingInvolvementWithTransferredFinancialAssetsCustodialEscrowBalance	11800000	USD
CY2019Q4	mbwm	Continuing Involvement With Transferred Financial Assets Custodial Escrow Balance ContinuingInvolvementWithTransferredFinancialAssetsCustodialEscrowBalance	6400000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	4652000	USD
CY2018Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	4436000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	6467000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Additions ServicingAssetAtAmortizedValueAdditions	1962000	USD
CY2020	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	2930000	USD
CY2019	us-gaap	Servicing Asset At Amortized Value Amortization1 ServicingAssetAtAmortizedValueAmortization1	1746000	USD
CY2020Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	8189000	USD
CY2019Q4	us-gaap	Servicing Asset At Amortized Value ServicingAssetAtAmortizedValue	4652000	USD
CY2019Q4	us-gaap	Valuation Allowance For Impairment Of Recognized Servicing Assets Balance ValuationAllowanceForImpairmentOfRecognizedServicingAssetsBalance	0	USD
CY2020Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	10000000.0	USD
CY2019Q4	us-gaap	Servicing Asset At Fair Value Amount ServicingAssetAtFairValueAmount	7400000	USD
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.0775	pure
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.140	pure
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Expected Credit Losses ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueExpectedCreditLosses	0.0040	pure
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Discount Rate ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueDiscountRate	0.100	pure
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Prepayment Speed ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValuePrepaymentSpeed	0.153	pure
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Expected Credit Losses ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueExpectedCreditLosses	0.0032	pure
CY2020	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P6Y1M6D
CY2019	us-gaap	Servicing Assets And Servicing Liabilities At Fair Value Assumptions Used To Estimate Fair Value Weighted Average Life1 ServicingAssetsAndServicingLiabilitiesAtFairValueAssumptionsUsedToEstimateFairValueWeightedAverageLife1	P5Y3M18D
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense Next Twelve Months MortgageServicingRightsAmortizationExpenseNextTwelveMonths	1724000	USD
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	338070000	USD
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Two MortgageServicingRightsAmortizationExpenseYearTwo	1476000	USD
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Three MortgageServicingRightsAmortizationExpenseYearThree	1241000	USD
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Four MortgageServicingRightsAmortizationExpenseYearFour	1026000	USD
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense Year Five MortgageServicingRightsAmortizationExpenseYearFive	834000	USD
CY2020Q4	mbwm	Mortgage Servicing Rights Amortization Expense After Year Five MortgageServicingRightsAmortizationExpenseAfterYearFive	1888000	USD
CY2019Q4	us-gaap	Finite Lived Core Deposits Gross FiniteLivedCoreDepositsGross	17500000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	15100000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2400000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	13700000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	3800000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	1086000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	768000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	450000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	132000	USD
CY2020Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1433403000	USD
CY2020Q4	mbwm	Percentage Of Non Interest Bearing Domestic Deposits To Deposits Demand PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand	0.420	pure
CY2019Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	924916000	USD
CY2019Q4	mbwm	Percentage Of Non Interest Bearing Domestic Deposits To Deposits Demand PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand	0.344	pure
CY2020	mbwm	Percentage Of Increase Decrease In Non Interest Bearing Demand Deposits PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits	0.550	pure
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Checking InterestBearingDomesticDepositChecking	473053000	USD
CY2020Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Checking PercentageOfInterestBearingDomesticDepositsToDepositsChecking	0.139	pure
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Checking InterestBearingDomesticDepositChecking	332373000	USD
CY2019Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Checking PercentageOfInterestBearingDomesticDepositsToDepositsChecking	0.123	pure
CY2020	mbwm	Percentage Of Increase Decrease Of Interest Bearing Checking Deposits PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits	0.423	pure
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	611912000	USD
CY2020Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Money Market PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket	0.179	pure
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	509368000	USD
CY2019Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Money Market PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket	0.189	pure
CY2020	mbwm	Percentage Of Increase Decrease In Money Market Deposits PercentageOfIncreaseDecreaseInMoneyMarketDeposits	0.201	pure
CY2020Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.099	pure
CY2019Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	269318000	USD
CY2019Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.100	pure
CY2020Q4	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	165548000	USD
CY2020Q4	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.049	pure
CY2019Q4	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	198123000	USD
CY2019Q4	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.074	pure
CY2020	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits Under100000 PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000	-0.164	pure
CY2020Q4	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	342633000	USD
CY2020Q4	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.100	pure
CY2019Q4	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	322827000	USD
CY2019Q4	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.120	pure
CY2020	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits100000 And Over PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver	0.061	pure
CY2020	mbwm	Percentage Of Increase Or Decrease Of Savings Deposits PercentageOfIncreaseOrDecreaseOfSavingsDeposits	0.255	pure
CY2020Q4	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	3364619000	USD
CY2020Q4	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	0.986	pure
CY2019Q4	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	2556925000	USD
CY2019Q4	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	0.950	pure
CY2020	mbwm	Aggregate Percentage Increase Decrease In Local Deposits AggregatePercentageIncreaseDecreaseInLocalDeposits	0.316	pure
CY2020Q4	mbwm	Out Of Area Time Deposits100000 And Over OutOfAreaTimeDeposits100000AndOver	46934000	USD
CY2020Q4	mbwm	Percentage Of Out Of Area Time Deposits100000 And Over PercentageOfOutOfAreaTimeDeposits100000AndOver	0.014	pure
CY2019Q4	mbwm	Out Of Area Time Deposits100000 And Over OutOfAreaTimeDeposits100000AndOver	133459000	USD
CY2019Q4	mbwm	Percentage Of Out Of Area Time Deposits100000 And Over PercentageOfOutOfAreaTimeDeposits100000AndOver	0.050	pure
CY2020	mbwm	Percentage Of Increase Decrease In Out Of Area Time100000 And Over PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver	-0.648	pure
CY2020Q4	us-gaap	Deposits Deposits	3411553000	USD
CY2020Q4	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
CY2019Q4	us-gaap	Deposits Deposits	2690384000	USD
CY2019Q4	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
CY2020	mbwm	Aggregate Increase Decrease In Percentage Of Deposits AggregateIncreaseDecreaseInPercentageOfDeposits	0.268	pure
CY2020Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	327246000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year One TimeDepositMaturitiesYearOne	360395000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	139801000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Two TimeDepositMaturitiesYearTwo	173512000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	39801000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Three TimeDepositMaturitiesYearThree	82480000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	25577000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Four TimeDepositMaturitiesYearFour	16019000	USD
CY2020Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	22690000	USD
CY2019Q4	us-gaap	Time Deposit Maturities Year Five TimeDepositMaturitiesYearFive	22003000	USD
CY2020Q4	us-gaap	Time Deposits TimeDeposits	555115000	USD
CY2019Q4	us-gaap	Time Deposits TimeDeposits	654409000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	79500000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Or Less ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsOrLess	100635000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	79373000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Three Months Through Six Months ContractualMaturitiesTimeDeposits100000OrMoreThreeMonthsThroughSixMonths	59838000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Three To Four Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate	80000000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	77363000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More Six Months Through12 Months ContractualMaturitiesTimeDeposits100000OrMoreSixMonthsThrough12Months	93691000	USD
CY2020Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More After12 Months ContractualMaturitiesTimeDeposits100000OrMoreAfter12Months	153331000	USD
CY2019Q4	us-gaap	Contractual Maturities Time Deposits100000 Or More After12 Months ContractualMaturitiesTimeDeposits100000OrMoreAfter12Months	202122000	USD
CY2020Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	389567000	USD
CY2019Q4	us-gaap	Time Deposits100000 Or More TimeDeposits100000OrMore	456286000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	272000000	USD
CY2019Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	320000000	USD
CY2020	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<table border="0" cellpadding="0" cellspacing="0" class="finTable" style="margin-right: 5%; margin-left: 9pt; width: 95%; font-size: 10pt; font-family: "Times New Roman", Times, serif; text-indent: 0px;"><tbody><tr style="vertical-align: bottom;"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">2020</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; padding-bottom: 1px;"> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td colspan="2" style="text-align: center; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:center;">2019</p> </td><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; padding-bottom: 1px;"> </td></tr> <tr style="vertical-align: bottom;"><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt; width: 68%;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Outstanding balance at year-end</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">118,365,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">102,675,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Weighted average interest rate at year-end</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">0.12</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">%</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">0.17</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">%</p> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Average daily balance during the year</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">132,880,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">105,234,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Weighted average interest rate during the year</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">0.12</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">%</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">0.24</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:'Times New Roman', Times, serif;font-size:10pt;margin:0pt;text-align:left;">%</p> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td><td> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"><td style="font-family: "Times New Roman", Times, serif; font-size: 10pt;"> <p style="font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-top: 0pt; margin-bottom: 0pt;">Maximum daily balance during the year</p> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">173,186,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt;"> </td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;">133,411,000</td><td style="width: 1%; font-family: "Times New Roman", Times, serif; font-size: 10pt; margin-left: 0pt;"> </td></tr> </tbody></table>
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	118365000	USD
CY2019Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	102675000	USD
CY2020	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	132880000	USD
CY2019	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	105234000	USD
CY2020	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	173186000	USD
CY2019	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	133411000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	754000000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	354000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	20000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	94000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	80000000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	10978000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Four To Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromFourToFiveYearsOfBalanceSheetDate	50000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due After Five Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueAfterFiveYearsOfBalanceSheetDate	70000000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	10170000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	14945000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-4141000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	26000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-372000	USD
CY2020	mbwm	Income Tax Expense Benefit Continuing Operations Change In Valuation Allowance IncomeTaxExpenseBenefitContinuingOperationsChangeInValuationAllowance	-94000	USD
CY2019	mbwm	Income Tax Expense Benefit Continuing Operations Change In Valuation Allowance IncomeTaxExpenseBenefitContinuingOperationsChangeInValuationAllowance	0	USD
CY2018	mbwm	Income Tax Expense Benefit Continuing Operations Change In Valuation Allowance IncomeTaxExpenseBenefitContinuingOperationsChangeInValuationAllowance	0	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11004000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9798000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	11518000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	12697000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	10883000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	681000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	644000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	620000	USD
CY2020	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	238000	USD
CY2019	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	804000	USD
CY2018	mbwm	Effective Income Tax Reconciliation Bank Owned Life Insurance EffectiveIncomeTaxReconciliationBankOwnedLifeInsurance	201000	USD
CY2020	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-94000	USD
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2020	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	205000	USD
CY2019	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-245000	USD
CY2018	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-264000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	10710000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11004000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	9798000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21	pure
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	7973000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Provision For Loan Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsProvisionForLoanLosses	5017000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	511000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	577000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	541000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Share Based Compensation Cost DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost	720000	USD
CY2020Q4	mbwm	Deferred Tax Assets Non Accrual Loan Interest Income DeferredTaxAssetsNonAccrualLoanInterestIncome	211000	USD
CY2019Q4	mbwm	Deferred Tax Assets Non Accrual Loan Interest Income DeferredTaxAssetsNonAccrualLoanInterestIncome	239000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	924000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	104000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Capital Loss Carryforwards DeferredTaxAssetsCapitalLossCarryforwards	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Capital Loss Carryforwards DeferredTaxAssetsCapitalLossCarryforwards	94000	USD
CY2020Q4	mbwm	Deferred Tax Assets Fair Value Write Downs On Foreclosed Properties DeferredTaxAssetsFairValueWriteDownsOnForeclosedProperties	537000	USD
CY2019Q4	mbwm	Deferred Tax Assets Fair Value Write Downs On Foreclosed Properties DeferredTaxAssetsFairValueWriteDownsOnForeclosedProperties	26000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	938000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	683000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	11635000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	7460000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	-0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	94000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	11635000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	7366000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1175000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	1743000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	297000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Prepaid Expenses DeferredTaxLiabilitiesPrepaidExpenses	269000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	498000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	787000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	1720000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Mortgage Servicing Rights DeferredTaxLiabilitiesMortgageServicingRights	977000	USD
CY2020Q4	mbwm	Deferred Tax Liabilities Unrealized Gains On Available For Sale Securities DeferredTaxLiabilitiesUnrealizedGainsOnAvailableForSaleSecurities	1458000	USD
CY2019Q4	mbwm	Deferred Tax Liabilities Unrealized Gains On Available For Sale Securities DeferredTaxLiabilitiesUnrealizedGainsOnAvailableForSaleSecurities	982000	USD
CY2020Q4	mbwm	Deferred Tax Liabilities Business Combination Adjustments DeferredTaxLiabilitiesBusinessCombinationAdjustments	2142000	USD
CY2019Q4	mbwm	Deferred Tax Liabilities Business Combination Adjustments DeferredTaxLiabilitiesBusinessCombinationAdjustments	2058000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	521000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	485000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	7811000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	7301000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	3824000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Liabilities Net DeferredTaxAssetsLiabilitiesNet	65000	USD
CY2020	us-gaap	Valuation Allowance Deferred Tax Asset Change In Amount ValuationAllowanceDeferredTaxAssetChangeInAmount	-100000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	0	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	361000
CY2020	mbwm	Interest Expense Deferred Compensation Plan InterestExpenseDeferredCompensationPlan	100000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0
CY2020Q4	mbwm	Related Party Deposits And Repurchase Agreements RelatedPartyDepositsAndRepurchaseAgreements	19400000	USD
CY2019Q4	mbwm	Related Party Deposits And Repurchase Agreements RelatedPartyDepositsAndRepurchaseAgreements	15000000.0	USD
CY2019Q4	mbwm	Reserve Or Liability Balance For Financial Instruments With Off Balance Sheet Risk ReserveOrLiabilityBalanceForFinancialInstrumentsWithOffBalanceSheetRisk	0	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1430195000	USD
CY2019Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1038444000	USD
CY2019Q4	mbwm	Amount Of Federal Reserve Required AmountOfFederalReserveRequired	10700000	USD
CY2014	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.0425	pure
CY2020	us-gaap	Defined Contribution Plan Employer Matching Contribution Percent DefinedContributionPlanEmployerMatchingContributionPercent	0.0500	pure
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1900000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1700000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	1600000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	24000000.0	USD
CY2019Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	5000000.0	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16268689
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16405159
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16600612
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.71
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.01
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.53
CY2020	us-gaap	Net Income Loss NetIncomeLoss	44138000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	49456000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	42024000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16268689
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16405159
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16600612
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	630
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	3976
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	5804
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16269319
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16409135
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16606416
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.71
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.01
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.53
CY2014Q2	mbwm	Fair Value Discount Of Subordinated Debentures Related To Assumed Business Trusts At Time Af Merger FairValueDiscountOfSubordinatedDebenturesRelatedToAssumedBusinessTrustsAtTimeAfMerger	15000000.0	USD
CY2014Q2	mbwm	Amortization Of Fair Value Discount Related To Subordinated Debentures Of Assumed Business Trusts AmortizationOfFairValueDiscountRelatedToSubordinatedDebenturesOfAssumedBusinessTrusts	700000	USD
CY2014Q2	mbwm	Amortization Period Of Fair Value Discount Related To Subordinated Debentures Of Assumed Business Trusts AmortizationPeriodOfFairValueDiscountRelatedToSubordinatedDebenturesOfAssumedBusinessTrusts	P21Y6M
CY2020Q4	mbwm	Capital Conservation Buffer CapitalConservationBuffer	0.025	pure
CY2020Q4	mbwm	Common Equity Tier1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets CommonEquityTier1RiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.070	pure
CY2020Q4	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.085	pure
CY2020Q4	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.105	pure
CY2020Q4	us-gaap	Statutory Accounting Practices Statutory Amount Available For Dividend Payments Without Regulatory Approval StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval	85700000	USD
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.28
CY2019Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000.0	USD
CY2020Q1	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	222000
CY2020Q1	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	6300000	USD
CY2020Q4	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	14000
CY2020Q4	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	300000	USD
CY2020Q4	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	22.05
CY2020Q4	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	10000000.0	USD
CY2020Q4	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	45500000	USD
CY2019Q4	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	44800000	USD
CY2020	mbwm	Maximum Restricted Core Element Allowed In Tier One Capital Percent MaximumRestrictedCoreElementAllowedInTierOneCapitalPercent	0.25	pure
CY2009Q4	mbwm	Maximum Level Of Consolidated Aggregate Assets Allowing For Inclusion Of Trust Preferred Securities In Tier One Capital MaximumLevelOfConsolidatedAggregateAssetsAllowingForInclusionOfTrustPreferredSecuritiesInTierOneCapital	15000000000.0	USD
CY2020Q4	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	45500000	USD
CY2019Q4	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	44800000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	5500000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	3700000	USD
CY2020Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	37935000	USD
CY2020Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	30317000	USD
CY2020Q1	us-gaap	Net Income Loss NetIncomeLoss	10673000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.65
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.65
CY2020Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	37164000	USD
CY2020Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	30571000	USD
CY2020Q2	us-gaap	Net Income Loss NetIncomeLoss	8697000	USD
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.54
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.54
CY2020Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	35594000	USD
CY2020Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	29509000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	10686000	USD
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.66
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.66
CY2020Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	37620000	USD
CY2020Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	31849000	USD
CY2020Q4	us-gaap	Net Income Loss NetIncomeLoss	14082000	USD
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.86
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.86
CY2019Q1	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	38637000	USD
CY2019Q1	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	30645000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	11824000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.72
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.72
CY2019Q2	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	39820000	USD
CY2019Q2	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	31116000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	11715000	USD
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.71
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	40316000	USD
CY2019Q4	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	31168000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	13317000	USD
CY2019Q3	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	31605000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	12600000	USD
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.77
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.77
CY2019Q4	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	39564000	USD
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.81
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.81

Files In Submission

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$MBWM
Mercantile Bank Corp Stock $mbwm

2020 Q4 Form 10-K Financial Statement

#000143774921005133 Filed on March 05, 2021

Income Statement

Balance Sheet

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Facts In Submission

Files In Submission

$MBWM Mercantile Bank Corp Stock $mbwm

2020 Q4 Form 10-K Financial Statement

#000143774921005133 Filed on March 05, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$MBWM
Mercantile Bank Corp Stock $mbwm