$MBWM
Mercantile Bank Corp Stock $mbwm

$mbwm Overview Financials Valuation SEC Filings Company Website

2021 Q4 Form 10-Q Financial Statement

#000143774921025404 Filed on November 05, 2021

Income Statement

Concept	2021 Q4	2021 Q3	2020 Q3
Revenue	$37.05M	$35.89M	$35.59M
YoY Change	-1.53%	0.83%	-11.71%
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	$3.480M	$1.500M	$1.300M
YoY Change	9.78%	15.38%	44.44%
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense		$4.764M	$6.085M
YoY Change		-21.71%	-30.15%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$15.22M	$18.58M	$13.19M
YoY Change	-14.21%	40.85%	-15.18%
Income Tax	$3.580M	$3.531M	$2.507M
% Of Pretax Income	23.52%	19.0%	19.0%
Net Earnings	$11.64M	$15.05M	$10.69M
YoY Change	-17.35%	40.85%	-15.19%
Net Earnings / Revenue	31.42%	41.94%	30.02%
Basic Earnings Per Share	$0.74	$0.95	$0.66
Diluted Earnings Per Share	$0.74	$0.95	$0.66
COMMON SHARES
Basic Shares Outstanding	15.67M	15.86M	16.23M
Diluted Shares Outstanding		15.86M	16.23M

Balance Sheet

Concept	2021 Q4	2021 Q3	2020 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$975.2M
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	$57.30M	$57.47M	$60.45M
YoY Change	-2.82%	-4.93%	10.74%
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	$5.258B	$4.964B	$4.421B
YoY Change	18.49%	12.3%	19.14%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$24.60M	$25.20M	$18.30M
YoY Change	1.23%	37.7%	-14.49%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt	$197.5M	$175.9M	$157.0M
YoY Change	66.81%	12.04%	50.96%
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$24.60M	$25.20M	$18.30M
YoY Change	1.23%	37.7%	-14.49%
LONG-TERM LIABILITIES
Long-Term Debt	$121.9M	$48.10M	$47.40M
YoY Change	156.09%	1.48%	1.5%
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities	$121.9M	$48.10M	$47.40M
YoY Change	156.09%	1.48%	1.5%
TOTAL LIABILITIES
Total Short-Term Liabilities	$24.60M	$25.20M	$18.30M
Total Long-Term Liabilities	$121.9M	$48.10M	$47.40M
Total Liabilities	$4.801B	$4.512B	$3.989B
YoY Change	20.16%	13.12%	20.75%
SHAREHOLDERS EQUITY
Retained Earnings	$174.5M	$167.5M	$124.5M
YoY Change	30.21%	34.62%	25.87%
Common Stock	$285.8M	$285.0M	$301.9M
YoY Change	-5.39%	-5.59%	-0.71%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$456.6M	$452.3M	$431.9M
YoY Change
Total Liabilities & Shareholders Equity	$5.258B	$4.964B	$4.421B
YoY Change	18.49%	12.3%	19.14%

Cashflow Statement

Concept	2021 Q4	2021 Q3	2020 Q3
OPERATING ACTIVITIES
Net Income	$11.64M	$15.05M	$10.69M
YoY Change	-17.35%	40.85%	-15.19%
Depreciation, Depletion And Amortization	$3.480M	$1.500M	$1.300M
YoY Change	9.78%	15.38%	44.44%
Cash From Operating Activities	$45.40M	-$3.010M	$28.70M
YoY Change	110.48%	-110.49%	362.16%
INVESTING ACTIVITIES
Capital Expenditures	-$1.350M	-$690.0K	-$2.770M
YoY Change	-24.58%	-75.09%	-26.13%
Acquisitions
YoY Change
Other Investing Activities	-$177.7M	-$121.0M	-$37.55M
YoY Change	-421.08%	222.21%	-3.45%
Cash From Investing Activities	-$179.1M	-$121.7M	-$40.32M
YoY Change	-434.34%	201.81%	-5.44%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	283.5M	190.5M	94.99M
YoY Change	-7720.16%	100.57%	-17.07%
NET CHANGE
Cash From Operating Activities	45.40M	-3.010M	28.70M
Cash From Investing Activities	-179.1M	-121.7M	-40.32M
Cash From Financing Activities	283.5M	190.5M	94.99M
Net Change In Cash	149.8M	65.82M	83.37M
YoY Change	109.77%	-21.05%	6.73%
FREE CASH FLOW
Cash From Operating Activities	$45.40M	-$3.010M	$28.70M
Capital Expenditures	-$1.350M	-$690.0K	-$2.770M
Free Cash Flow	$46.75M	-$2.320M	$31.47M
YoY Change	100.13%	-107.37%	215.96%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020Q4	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	626006000	USD
CY2021Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	15670645
CY2021Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2021Q3	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2020Q4	us-gaap	Preferred Stock No Par Value PreferredStockNoParValue	0
CY2021Q3	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	1000000
CY2020Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	1000000
CY2021Q3	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0
CY2020Q4	us-gaap	Preferred Stock Shares Issued PreferredStockSharesIssued	0
CY2021Q3	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2020Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2021Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	40000000
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	40000000
CY2021Q3	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	15717663
CY2021Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	15717663
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	16425136
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	16425136
	mbwm	Loans And Leases Receivable Nonaccrual Loans Interest Income Recognized LoansAndLeasesReceivableNonaccrualLoansInterestIncomeRecognized	0	USD
CY2020Q3	mbwm	Loans And Leases Receivable Nonaccrual Loans Interest Income Recognized LoansAndLeasesReceivableNonaccrualLoansInterestIncomeRecognized	0	USD
	mbwm	Loans And Leases Receivable Nonaccrual Loans Interest Income Recognized LoansAndLeasesReceivableNonaccrualLoansInterestIncomeRecognized	0	USD
CY2020Q3	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	100000	USD
CY2021Q3	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	92907000	USD
	us-gaap	Repurchase Agreement Counterparty Weighted Average Maturity Of Agreements1 RepurchaseAgreementCounterpartyWeightedAverageMaturityOfAgreements1	P1Y
CY2020Q4	mbwm	Reserve Or Liability Balance For Financial Instruments With Off Balance Sheet Risk ReserveOrLiabilityBalanceForFinancialInstrumentsWithOffBalanceSheetRisk	0	USD
CY2021Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.29
CY2021Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.29
CY2021Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.30
CY2021Q3	us-gaap	Cash And Due From Banks CashAndDueFromBanks	83804000	USD
CY2020Q4	us-gaap	Cash And Due From Banks CashAndDueFromBanks	62832000	USD
CY2021Q3	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	741557000	USD
CY2020Q4	us-gaap	Interest Bearing Deposits In Banks InterestBearingDepositsInBanks	563174000	USD
CY2021Q3	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	825361000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	559564000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	387347000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	18002000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Stock FederalHomeLoanBankStock	18002000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3313709000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3193470000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	37423000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Allowance LoansAndLeasesReceivableAllowance	37967000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	3276286000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Reported Amount LoansAndLeasesReceivableNetReportedAmount	3155503000	USD
CY2021Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	57465000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	58959000	USD
CY2021Q3	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	72963000	USD
CY2020Q4	us-gaap	Bank Owned Life Insurance BankOwnedLifeInsurance	72131000	USD
CY2021Q3	us-gaap	Goodwill Goodwill	49473000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	49473000	USD
CY2021Q3	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1589000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	2436000	USD
CY2021Q3	mbwm	Mortgage Loans Held For Sale MortgageLoansHeldForSale	47247000	USD
CY2020Q4	mbwm	Mortgage Loans Held For Sale MortgageLoansHeldForSale	22888000	USD
CY2021Q3	us-gaap	Other Assets OtherAssets	56462000	USD
CY2020Q4	us-gaap	Other Assets OtherAssets	44599000	USD
CY2021Q3	us-gaap	Assets Assets	4964412000	USD
CY2020Q4	us-gaap	Assets Assets	4437344000	USD
CY2021Q3	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1647380000	USD
CY2020Q4	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1433403000	USD
CY2021Q3	us-gaap	Interest Bearing Deposit Liabilities Domestic InterestBearingDepositLiabilitiesDomestic	2221611000	USD
CY2020Q4	us-gaap	Interest Bearing Deposit Liabilities Domestic InterestBearingDepositLiabilitiesDomestic	1978150000	USD
CY2021Q3	us-gaap	Deposits Deposits	3868991000	USD
CY2020Q4	us-gaap	Deposits Deposits	3411553000	USD
CY2021Q3	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	175850000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	118365000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	394000000	USD
CY2020Q4	us-gaap	Federal Home Loan Bank Advances Long Term FederalHomeLoanBankAdvancesLongTerm	394000000	USD
CY2021Q3	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	48074000	USD
CY2020Q4	us-gaap	Junior Subordinated Debenture Owed To Unconsolidated Subsidiary Trust JuniorSubordinatedDebentureOwedToUnconsolidatedSubsidiaryTrust	47563000	USD
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CY2020Q4	us-gaap	Accrued Liabilities Current And Noncurrent AccruedLiabilitiesCurrentAndNoncurrent	24309000	USD
CY2021Q3	us-gaap	Liabilities Liabilities	4512134000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	3995790000	USD
CY2021Q3	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2020Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	USD
CY2021Q3	us-gaap	Common Stock Value CommonStockValue	285033000	USD
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	302029000	USD
CY2021Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	167541000	USD
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CY2021Q3	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-296000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	5486000	USD
CY2021Q3	us-gaap	Stockholders Equity StockholdersEquity	452278000	USD
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CY2021Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	4964412000	USD
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	us-gaap	Interest And Fee Income Loans And Leases InterestAndFeeIncomeLoansAndLeases	101428000	USD
CY2021Q3	us-gaap	Interest Income Securities Taxable InterestIncomeSecuritiesTaxable	1341000	USD
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	us-gaap	Interest Expense Short Term Borrowings InterestExpenseShortTermBorrowings	132000	USD
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	us-gaap	Interest Expense Subordinated Notes And Debentures InterestExpenseSubordinatedNotesAndDebentures	1857000	USD
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CY2020Q3	us-gaap	Interest Expense InterestExpense	6085000	USD
	us-gaap	Interest Expense InterestExpense	14919000	USD
	us-gaap	Interest Expense InterestExpense	20296000	USD
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	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	91528000	USD
	us-gaap	Interest Income Expense Net InterestIncomeExpenseNet	90397000	USD
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	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11550000	USD
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CY2020Q3	mbwm	Interest Rate Swap Program Fees InterestRateSwapProgramFees	0	USD
	mbwm	Interest Rate Swap Program Fees InterestRateSwapProgramFees	6086000	USD
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CY2020Q3	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	290000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	872000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	933000	USD
CY2021Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
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	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	1058000	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2021Q3	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1095000	USD
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	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1916000	USD
	us-gaap	Noninterest Income Other Operating Income NoninterestIncomeOtherOperatingIncome	1042000	USD
CY2021Q3	us-gaap	Noninterest Income NoninterestIncome	15568000	USD
CY2020Q3	us-gaap	Noninterest Income NoninterestIncome	13307000	USD
	us-gaap	Noninterest Income NoninterestIncome	43587000	USD
	us-gaap	Noninterest Income NoninterestIncome	30839000	USD
CY2021Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	15975000	USD
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	us-gaap	Labor And Related Expense LaborAndRelatedExpense	47255000	USD
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	44388000	USD
CY2021Q3	us-gaap	Occupancy Net OccupancyNet	2030000	USD
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	us-gaap	Occupancy Net OccupancyNet	6021000	USD
	us-gaap	Occupancy Net OccupancyNet	5944000	USD
CY2021Q3	us-gaap	Equipment Expense EquipmentExpense	929000	USD
CY2020Q3	us-gaap	Equipment Expense EquipmentExpense	871000	USD
	us-gaap	Equipment Expense EquipmentExpense	2719000	USD
	us-gaap	Equipment Expense EquipmentExpense	2500000	USD
CY2021Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	2746000	USD
CY2020Q3	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	2676000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	8138000	USD
	us-gaap	Information Technology And Data Processing InformationTechnologyAndDataProcessing	7793000	USD
CY2021Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4530000	USD
CY2020Q3	us-gaap	Other Noninterest Expense OtherNoninterestExpense	4119000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	13386000	USD
	us-gaap	Other Noninterest Expense OtherNoninterestExpense	11954000	USD
CY2021Q3	us-gaap	Noninterest Expense NoninterestExpense	26210000	USD
CY2020Q3	us-gaap	Noninterest Expense NoninterestExpense	26423000	USD
	us-gaap	Noninterest Expense NoninterestExpense	77519000	USD
	us-gaap	Noninterest Expense NoninterestExpense	72579000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	18582000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	13193000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	58496000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	37107000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	3531000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2507000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	11114000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7051000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	15051000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	10686000	USD
	us-gaap	Net Income Loss NetIncomeLoss	47382000	USD
	us-gaap	Net Income Loss NetIncomeLoss	30056000	USD
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.95
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.66
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.95
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.85
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.95
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.66
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.95
CY2020Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.28
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.88
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.84
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	15859955
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16233196
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16084806
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16265208
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.85
CY2021Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.30
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	15860314
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16233666
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16085274
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16265986
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	15051000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	10686000	USD
	us-gaap	Net Income Loss NetIncomeLoss	47382000	USD
	us-gaap	Net Income Loss NetIncomeLoss	30056000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-2281000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-675000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	-7318000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Before Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodBeforeTax	2352000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-479000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-143000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-1536000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	494000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-1802000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-532000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-5782000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	1858000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	13249000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	10154000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	41600000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	31914000	USD
CY2021Q2	us-gaap	Stockholders Equity StockholdersEquity	451888000	USD
CY2021Q3	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	13000	USD
CY2021Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	237000	USD
CY2021Q3	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	50000	USD
CY2021Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	448000	USD
CY2021Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	8947000	USD
CY2021Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	4660000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	15051000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-1802000	USD
CY2021Q3	us-gaap	Stockholders Equity StockholdersEquity	452278000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	441554000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	35000	USD
	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	648000	USD
	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	344000	USD
	us-gaap	Stock Issued During Period Value Stock Options Exercised StockIssuedDuringPeriodValueStockOptionsExercised	50000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	1725000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	19798000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	13880000	USD
	us-gaap	Net Income Loss NetIncomeLoss	47382000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-5782000	USD
CY2021Q3	us-gaap	Stockholders Equity StockholdersEquity	452278000	USD
CY2020Q2	us-gaap	Stockholders Equity StockholdersEquity	425221000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	12000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	206000	USD
CY2020Q3	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	45000	USD
CY2020Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	736000	USD
CY2020Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	4474000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	10686000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-532000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	431900000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	416561000	USD
	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	37000	USD
	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	610000	USD
	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	394000	USD
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2102000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6282000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	13436000	USD
	us-gaap	Net Income Loss NetIncomeLoss	30056000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	1858000	USD
CY2020Q3	us-gaap	Stockholders Equity StockholdersEquity	431900000	USD
	us-gaap	Net Income Loss NetIncomeLoss	47382000	USD
	us-gaap	Net Income Loss NetIncomeLoss	30056000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	10200000	USD
	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	6262000	USD
	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	102000	USD
	mbwm	Discount Accretion On Acquired Loans DiscountAccretionOnAcquiredLoans	337000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-900000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11550000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	1725000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	2102000	USD
	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	344000	USD
	us-gaap	Issuance Of Stock And Warrants For Services Or Claims IssuanceOfStockAndWarrantsForServicesOrClaims	394000	USD
	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	509763000	USD
	us-gaap	Proceeds From Sale Of Mortgage Loans Held For Sale ProceedsFromSaleOfMortgageLoansHeldForSale	505602000	USD
	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	510571000	USD
	us-gaap	Payments For Origination Of Mortgage Loans Held For Sale PaymentsForOriginationOfMortgageLoansHeldForSale	506683000	USD
	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	23551000	USD
	us-gaap	Gain Loss On Sale Of Mortgage Loans GainLossOnSaleOfMortgageLoans	20055000	USD
	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	74000	USD
	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Foreclosed Assets NetGainLossFromSaleAndValuationWriteDownOfForeclosedAssets	183000	USD
	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	-243000	USD
	mbwm	Net Gain Loss From Sale And Valuation Write Down Of Former Bank Premises NetGainLossFromSaleAndValuationWriteDownOfFormerBankPremises	27000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-246000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-54000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	872000	USD
	us-gaap	Bank Owned Life Insurance Income BankOwnedLifeInsuranceIncome	933000	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	1058000	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	-0	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-853000	USD
	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	1080000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	15369000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	6269000	USD
	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	910000	USD
	us-gaap	Increase Decrease In Accrued Liabilities And Other Operating Liabilities IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities	-4147000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	19169000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	16306000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	129522000	USD
	us-gaap	Payments For Proceeds From Loans And Leases PaymentsForProceedsFromLoansAndLeases	472417000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	257967000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	270119000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	77531000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	296895000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	181000	USD
	us-gaap	Proceeds From Sale Of Foreclosed Assets ProceedsFromSaleOfForeclosedAssets	313000	USD
	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	270000	USD
	mbwm	Proceeds From Sale Of Former Bank Premises ProceedsFromSaleOfFormerBankPremises	162000	USD
	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	2679000	USD
	us-gaap	Payments For Proceeds From Businesses And Interest In Affiliates PaymentsForProceedsFromBusinessesAndInterestInAffiliates	-0	USD
	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	4250000	USD
	us-gaap	Payments For Proceeds From Productive Assets PaymentsForProceedsFromProductiveAssets	7201000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-316436000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-452367000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-113842000	USD
	us-gaap	Increase Decrease In Time Deposits IncreaseDecreaseInTimeDeposits	-65389000	USD
	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	585924000	USD
	us-gaap	Increase Decrease In Other Deposits IncreaseDecreaseInOtherDeposits	747039000	USD
	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	57485000	USD
	us-gaap	Proceeds From Payments For In Securities Sold Under Agreements To Repurchase ProceedsFromPaymentsForInSecuritiesSoldUnderAgreementsToRepurchase	54342000	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	-0	USD
	us-gaap	Repayments Of Federal Home Loan Bank Borrowings RepaymentsOfFederalHomeLoanBankBorrowings	20000000	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	0	USD
	us-gaap	Proceeds From Federal Home Loan Bank Borrowings ProceedsFromFederalHomeLoanBankBorrowings	60000000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	50000	USD
	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	USD
	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	35000	USD
	us-gaap	Proceeds From Stock Plans ProceedsFromStockPlans	37000	USD
	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	648000	USD
	us-gaap	Proceeds From Issuance Of Common Stock Dividend Reinvestment Plan ProceedsFromIssuanceOfCommonStockDividendReinvestmentPlan	610000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	19798000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	6282000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	13880000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	13436000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	496622000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	756921000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	199355000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	320860000	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
CY2021Q3	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	825361000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents And Federal Funds Sold CashCashEquivalentsAndFederalFundsSold	554591000	USD
	us-gaap	Interest Paid Net InterestPaidNet	15826000	USD
	us-gaap	Interest Paid Net InterestPaidNet	21798000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	14450000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	7950000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	30000	USD
	us-gaap	Transfer To Other Real Estate TransferToOtherRealEstate	146000	USD
	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	0	USD
	mbwm	Transfer Of Bank Premises To Other Real Estate Owned TransferOfBankPremisesToOtherRealEstateOwned	179000	USD
CY2021Q3	mbwm	Number Of Unconsolidated Business Trusts Formed To Issue Trust Preferred Securities NumberOfUnconsolidatedBusinessTrustsFormedToIssueTrustPreferredSecurities	5	pure
	mbwm	Interest Income On Commercial And Mortgage Loans Discontinued Period InterestIncomeOnCommercialAndMortgageLoansDiscontinuedPeriod	P90D
	mbwm	Maximum Delinquency Period For Consumer And Credit Card Loans To Be Charged Off MaximumDelinquencyPeriodForConsumerAndCreditCardLoansToBeChargedOff	P120D
CY2021Q3	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	49100000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	24000000.0	USD
CY2021Q3	us-gaap	Servicing Asset ServicingAsset	1260000000	USD
CY2020Q4	us-gaap	Servicing Asset ServicingAsset	1040000000.00	USD
	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<span style="text-decoration: underline; ">Out-of-Period Adjustment</span>: During the <em style="font: inherit;">second</em> quarter of <em style="font: inherit;">2021,</em> a formula error was identified in the spreadsheet used to calculate and record the present values of right-to-use assets consisting of several banking offices along with various printer and copy machines. As a result, Premises and Equipment, Net and Other Liabilities on our Consolidated Balance Sheets were understated by $2.8 million and $2.7 million as of <em style="font: inherit;"> December 31, 2020 </em>and <em style="font: inherit;"> March 31, 2021, </em>respectively. There was <em style="font: inherit;">no</em> impact to our Consolidated Statements of Income. We evaluated the impact, both individually and in the aggregate, and determined these out-of-period adjustments were <em style="font: inherit;">not</em> material to our Consolidated Balance Sheets in the respective impacted periods.
CY2021Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	559938000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	5582000	USD
CY2021Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	5956000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	559564000	USD
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
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months	341046000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	4954000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger	49160000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	1002000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	390206000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	5956000	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
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Number Of Positions DebtSecuritiesAvailableForSaleUnrealizedLossPositionNumberOfPositions	291	pure
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position DebtSecuritiesAvailableForSaleUnrealizedLossPosition	390000000	USD
CY2021Q3	us-gaap	Debt Securities Available For Sale Unrealized Loss Position Accumulated Loss DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss	6000000.0	USD
CY2021Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	0	USD
CY2021Q3	mbwm	Weighted Average Yield Of Securities Portfolio Due In One Year Or Less WeightedAverageYieldOfSecuritiesPortfolioDueInOneYearOrLess	0.0225	pure
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities Remainder Of Fiscal Year Amortized Cost Basis AvailableForSaleSecuritiesDebtMaturitiesRemainderOfFiscalYearAmortizedCostBasis	545000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities Remainder Of Fiscal Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesRemainderOfFiscalYearFairValue	547000	USD
CY2021Q3	mbwm	Weighted Average Yield Of Securities Portfolio Due From One To Five Years WeightedAverageYieldOfSecuritiesPortfolioDueFromOneToFiveYears	0.0101	pure
CY2021Q3	mbwm	Debt Securities Availableforsale Amortized Cost Maturity Allocated And Single Maturity Date Year One Through Five DebtSecuritiesAvailableforsaleAmortizedCostMaturityAllocatedAndSingleMaturityDateYearOneThroughFive	187220000	USD
CY2021Q3	mbwm	Debt Securities Availableforsale Fair Value Maturity Allocated And Single Maturity Date Year One Through Five DebtSecuritiesAvailableforsaleFairValueMaturityAllocatedAndSingleMaturityDateYearOneThroughFive	188005000	USD
CY2021Q3	mbwm	Weighted Average Yield Of Securities Portfolio Due From Five To Ten Years WeightedAverageYieldOfSecuritiesPortfolioDueFromFiveToTenYears	0.0156	pure
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost	266478000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue	265719000	USD
CY2021Q3	mbwm	Weighted Average Yield Of Securities Portfolio Due Afterten Years WeightedAverageYieldOfSecuritiesPortfolioDueAftertenYears	0.0198	pure
CY2021Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3313709000	USD
CY2021Q3	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3193470000	USD
CY2020Q4	mbwm	Loan Portfolio Classes And Segments As Percentage Of Aggregate Loan LoanPortfolioClassesAndSegmentsAsPercentageOfAggregateLoan	1.000	pure
	mbwm	Loans And Leases Receivable Net Of Deferred Income Increase Decrease Percentage LoansAndLeasesReceivableNetOfDeferredIncomeIncreaseDecreasePercentage	0.038	pure
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Amortized Cost AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost	65896000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities After Ten Years Fair Value AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue	65340000	USD
CY2021Q3	mbwm	Weighted Average Yield Of Securities Portfolio WeightedAverageYieldOfSecuritiesPortfolio	0.0144	pure
CY2021Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	559938000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	559564000	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3310000000	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3190000000	USD
	mbwm	Loans And Leases Receivable Period Increase Decrease LoansAndLeasesReceivablePeriodIncreaseDecrease	120000000	USD
	mbwm	Loans And Leases Receivable Percentage Period Increase Decrease LoansAndLeasesReceivablePercentagePeriodIncreaseDecrease	0.038	pure
CY2021Q3	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3313709000	USD
CY2021Q3	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2020Q4	us-gaap	Loans And Leases Receivable Net Of Deferred Income LoansAndLeasesReceivableNetOfDeferredIncome	3193470000	USD
CY2020Q4	us-gaap	Financing Receivable Recorded Investment90 Days Past Due And Still Accruing FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing	0	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance	20453000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment	19102000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	18958000	USD
	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	20892000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With Related Allowance Unpaid Principal Balance ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance	4326000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With Related Allowance Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment	4307000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	765000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	4703000	USD
	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	3387000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Unpaid Principal Balance ImpairedFinancingReceivableUnpaidPrincipalBalance	24779000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Recorded Investment ImpairedFinancingReceivableRecordedInvestment	23409000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Related Allowance ImpairedFinancingReceivableRelatedAllowance	765000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	23661000	USD
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	24279000	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
CY2020Q3	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	15506000	USD
	us-gaap	Impaired Financing Receivable With No Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment	15459000	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
CY2020Q3	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	2667000	USD
	us-gaap	Impaired Financing Receivable With Related Allowance Average Recorded Investment ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment	2870000	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
CY2020Q3	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	18173000	USD
	us-gaap	Impaired Financing Receivable Average Recorded Investment ImpairedFinancingReceivableAverageRecordedInvestment	18329000	USD
CY2021Q3	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	400000	USD
CY2020Q3	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	200000	USD
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	1200000	USD
	us-gaap	Impaired Financing Receivable Interest Income Accrual Method ImpairedFinancingReceivableInterestIncomeAccrualMethod	800000	USD
CY2021Q3	mbwm	Loans And Leases Receivable Nonaccrual Loans Interest Income Recognized LoansAndLeasesReceivableNonaccrualLoansInterestIncomeRecognized	0	USD
CY2021Q3	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	100000	USD
	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	100000	USD
	us-gaap	Loans And Leases Receivable Impaired Interest Lost On Nonaccrual Loans LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans	200000	USD
CY2021Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	35913000	USD
CY2021Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	1900000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	743000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	353000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37423000	USD
CY2020Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37967000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	-900000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	865000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	1221000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	37423000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	765000	USD
CY2021Q3	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	36658000	USD
CY2021Q3	mbwm	Loans And Leases Receivable Net Of Deferred Income Excluding Ppp Loans LoansAndLeasesReceivableNetOfDeferredIncomeExcludingPPPLoans	3198056000	USD
CY2021Q3	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	23409000	USD
CY2021Q3	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	3174647000	USD
CY2020Q2	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	32246000	USD
CY2020Q3	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	3200000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	123000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	249000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	35572000	USD
CY2019Q4	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	23889000	USD
	us-gaap	Provision For Loan And Lease Losses ProvisionForLoanAndLeaseLosses	11550000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Write Offs FinancingReceivableAllowanceForCreditLossesWriteOffs	499000	USD
	us-gaap	Financing Receivable Allowance For Credit Losses Recovery FinancingReceivableAllowanceForCreditLossesRecovery	632000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses FinancingReceivableAllowanceForCreditLosses	35572000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Individually Evaluated For Impairment1 FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1	910000	USD
CY2020Q3	us-gaap	Financing Receivable Allowance For Credit Losses Collectively Evaluated For Impairment FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment	34662000	USD
CY2020Q4	mbwm	Loans And Leases Receivable Net Of Deferred Income Excluding Ppp Loans LoansAndLeasesReceivableNetOfDeferredIncomeExcludingPPPLoans	2828211000	USD
CY2020Q4	us-gaap	Financing Receivable Individually Evaluated For Impairment FinancingReceivableIndividuallyEvaluatedForImpairment	26958000	USD
CY2020Q4	us-gaap	Financing Receivable Collectively Evaluated For Impairment FinancingReceivableCollectivelyEvaluatedForImpairment	2801253000	USD
CY2021Q3	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	3	pure
CY2021Q3	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	279000	USD
CY2021Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	278000	USD
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	18	pure
	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	4333000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	4329000	USD
CY2021Q3	us-gaap	Deposits Deposits	3870000000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	12	pure
CY2020Q3	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	784000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	784000	USD
	us-gaap	Financing Receivable Modifications Number Of Contracts2 FinancingReceivableModificationsNumberOfContracts2	34	pure
	us-gaap	Financing Receivable Modifications Pre Modification Recorded Investment2 FinancingReceivableModificationsPreModificationRecordedInvestment2	11074000	USD
	us-gaap	Financing Receivable Modifications Post Modification Recorded Investment2 FinancingReceivableModificationsPostModificationRecordedInvestment2	10478000	USD
	mbwm	Minimum Number Of Days Past Due At Period End For Loans Modified As Troubled Debt Restructurings MinimumNumberOfDaysPastDueAtPeriodEndForLoansModifiedAsTroubledDebtRestructurings	P30D
CY2021Q3	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	pure
CY2021Q3	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	5000	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	pure
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	5000	USD
CY2020Q3	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	0	pure
CY2020Q3	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	0	USD
	us-gaap	Financing Receivable Modifications Subsequent Default Number Of Contracts1 FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1	1	pure
	us-gaap	Financing Receivable Modifications Subsequent Default Recorded Investment1 FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1	31000	USD
CY2021Q3	mbwm	Allowance For Credit Losses Troubled Debt Restructuring AllowanceForCreditLossesTroubledDebtRestructuring	598000	USD
CY2020Q4	mbwm	Allowance For Credit Losses Troubled Debt Restructuring AllowanceForCreditLossesTroubledDebtRestructuring	467000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	94169000	USD
CY2021Q3	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	35442000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	35210000	USD
CY2021Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	57465000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	58959000	USD
CY2021Q3	us-gaap	Depreciation Depreciation	1500000	USD
CY2020Q3	us-gaap	Depreciation Depreciation	1300000	USD
	us-gaap	Depreciation Depreciation	4300000	USD
	us-gaap	Depreciation Depreciation	3800000	USD
	us-gaap	Increase Decrease In Deposits IncreaseDecreaseInDeposits	457000000	USD
	mbwm	Aggregate Increase Decrease In Percentage Of Deposits AggregateIncreaseDecreaseInPercentageOfDeposits	0.134	pure
CY2021Q3	us-gaap	Noninterest Bearing Domestic Deposit Demand NoninterestBearingDomesticDepositDemand	1647380000	USD
CY2021Q3	mbwm	Percentage Of Non Interest Bearing Domestic Deposits To Deposits Demand PercentageOfNonInterestBearingDomesticDepositsToDepositsDemand	0.426	pure
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
	mbwm	Percentage Of Increase Decrease In Non Interest Bearing Demand Deposits PercentageOfIncreaseDecreaseInNonInterestBearingDemandDeposits	0.149	pure
CY2021Q3	us-gaap	Interest Bearing Domestic Deposit Checking InterestBearingDomesticDepositChecking	535983000	USD
CY2021Q3	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Checking PercentageOfInterestBearingDomesticDepositsToDepositsChecking	0.139	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
	mbwm	Percentage Of Increase Decrease Of Interest Bearing Checking Deposits PercentageOfIncreaseDecreaseOfInterestBearingCheckingDeposits	0.133	pure
CY2021Q3	us-gaap	Interest Bearing Domestic Deposit Money Market InterestBearingDomesticDepositMoneyMarket	854763000	USD
CY2021Q3	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Money Market PercentageOfInterestBearingDomesticDepositsToDepositsMoneyMarket	0.221	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
	mbwm	Percentage Of Increase Decrease In Money Market Deposits PercentageOfIncreaseDecreaseInMoneyMarketDeposits	0.397	pure
CY2021Q3	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	392298000	USD
CY2021Q3	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.101	pure
CY2020Q4	us-gaap	Interest Bearing Domestic Deposit Savings InterestBearingDomesticDepositSavings	338070000	USD
CY2020Q4	us-gaap	Percentage Of Interest Bearing Domestic Deposits To Deposits Savings PercentageOfInterestBearingDomesticDepositsToDepositsSavings	0.099	pure
	mbwm	Percentage Of Increase Or Decrease Of Savings Deposits PercentageOfIncreaseOrDecreaseOfSavingsDeposits	0.160	pure
CY2021Q3	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	139031000	USD
CY2021Q3	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.036	pure
CY2020Q4	mbwm	Domestic Time Deposits Less Than100000 DomesticTimeDepositsLessThan100000	165548000	USD
CY2020Q4	mbwm	Percentage Of Domestic Time Deposits Under100000 PercentageOfDomesticTimeDepositsUnder100000	0.049	pure
	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits Under100000 PercentageOfIncreaseDecreaseInDomesticTimeDepositsUnder100000	-0.160	pure
CY2021Q3	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	275623000	USD
CY2021Q3	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.071	pure
CY2020Q4	mbwm	Domestic Time Deposits100000 Or More DomesticTimeDeposits100000OrMore	342633000	USD
CY2020Q4	mbwm	Percentage Of Domestic Time Deposits100000 And Over PercentageOfDomesticTimeDeposits100000AndOver	0.100	pure
	mbwm	Percentage Of Increase Decrease In Domestic Time Deposits100000 And Over PercentageOfIncreaseDecreaseInDomesticTimeDeposits100000AndOver	-0.196	pure
CY2021Q3	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	3845078000	USD
CY2021Q3	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	0.994	pure
CY2020Q4	mbwm	Aggregate Local Deposit Liabilities AggregateLocalDepositLiabilities	3364619000	USD
CY2020Q4	mbwm	Aggregate Percentage Of Local Deposits AggregatePercentageOfLocalDeposits	0.986	pure
	mbwm	Aggregate Percentage Increase Decrease In Local Deposits AggregatePercentageIncreaseDecreaseInLocalDeposits	0.143	pure
CY2021Q3	mbwm	Out Of Area Time Deposits100000 And Over OutOfAreaTimeDeposits100000AndOver	23913000	USD
CY2021Q3	mbwm	Percentage Of Out Of Area Time Deposits100000 And Over PercentageOfOutOfAreaTimeDeposits100000AndOver	0.006	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
	mbwm	Percentage Of Increase Decrease In Out Of Area Time100000 And Over PercentageOfIncreaseDecreaseInOutOfAreaTime100000AndOver	-0.490	pure
CY2021Q3	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	46000000.0	USD
CY2020Q4	mbwm	Preferred Securities Of Subsidiary Trust PreferredSecuritiesOfSubsidiaryTrust	45500000	USD
CY2021Q3	us-gaap	Deposits Deposits	3868991000	USD
CY2021Q3	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
CY2020Q4	us-gaap	Deposits Deposits	3411553000	USD
CY2020Q4	mbwm	Aggregate Percentage Of Deposits AggregatePercentageOfDeposits	1.000	pure
	mbwm	Aggregate Increase Decrease In Percentage Of Deposits AggregateIncreaseDecreaseInPercentageOfDeposits	0.134	pure
CY2021Q3	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	202000000	USD
CY2020Q4	us-gaap	Time Deposits At Or Above Fdic Insurance Limit TimeDepositsAtOrAboveFDICInsuranceLimit	272000000	USD
	us-gaap	Schedule Of Repurchase Agreements ScheduleOfRepurchaseAgreements	<table border="0" cellpadding="0" cellspacing="0" class="finTable" style="margin-right: 5%; margin-left: 18pt; width: 95%; font-size: 10pt; font-family: Times New Roman; text-indent: 0px;"><tbody><tr style="vertical-align: bottom;"><td style="font-family: Times New Roman; font-size: 10pt;"> </td><td style="font-family: Times New Roman; font-size: 10pt;"> </td><td colspan="2" style="text-align: center; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">Nine Months</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">Ended</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">September 30,</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">2021</p> </td><td style="font-family: Times New Roman; font-size: 10pt; padding-bottom: 1px;"> </td><td style="font-family: Times New Roman; font-size: 10pt;"> </td><td colspan="2" style="text-align: center; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt; border-bottom: 1px solid rgb(0, 0, 0);"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">Twelve Months</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">Ended</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">December 31,</p> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;text-align:center;margin:0pt;">2020</p> </td><td style="font-family: Times New Roman; 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; font-size: 10pt; width: 68%;"> <p style="font-family: Times New Roman; font-size: 10pt; font-variant: normal; margin-top: 0pt; margin-bottom: 0pt;">Outstanding balance at end of period</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">175,850,000</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">118,365,000</td><td style="width: 1%; font-family: Times New Roman; 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; font-size: 10pt;"> <p style="font-family: Times New Roman; font-size: 10pt; font-variant: normal; margin-top: 0pt; margin-bottom: 0pt;">Average interest rate at end of period</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">0.11</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">0.12</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</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; font-size: 10pt;"> <p style="font-family: Times New Roman; font-size: 10pt; font-variant: normal; margin-top: 0pt; margin-bottom: 0pt;">Average daily balance during the period</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">151,522,000</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">132,880,000</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204, 238, 255);"><td style="font-family: Times New Roman; font-size: 10pt;"> <p style="font-family: Times New Roman; font-size: 10pt; font-variant: normal; margin-top: 0pt; margin-bottom: 0pt;">Average interest rate during the period</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">0.11</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">0.12</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> <p style="font-family:Times New Roman;font-size:10pt;font-variant:normal;margin:0pt;">%</p> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(255, 255, 255);"><td style="font-family: Times New Roman; font-size: 10pt;"> <p style="font-family: Times New Roman; font-size: 10pt; font-variant: normal; margin-top: 0pt; margin-bottom: 0pt;">Maximum daily balance during the period</p> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">195,570,000</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt;"> </td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">$</td><td style="width: 13%; text-align: right; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;">173,186,000</td><td style="width: 1%; font-family: Times New Roman; font-size: 10pt; margin-left: 0pt;"> </td></tr> </tbody></table>
CY2021Q3	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	175850000	USD
CY2020Q4	us-gaap	Securities Sold Under Agreements To Repurchase SecuritiesSoldUnderAgreementsToRepurchase	118365000	USD
	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	151522000	USD
CY2020	us-gaap	Shortterm Debt Average Outstanding Amount ShorttermDebtAverageOutstandingAmount	132880000	USD
	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	195570000	USD
CY2020	us-gaap	Shortterm Debt Maximum Amount Outstanding During Period ShorttermDebtMaximumAmountOutstandingDuringPeriod	173186000	USD
CY2021Q3	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	760000000	USD
CY2021Q3	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	360000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due In Remainder Of Fiscal Year FederalHomeLoanBankAdvancesMaturitiesSummaryDueInRemainderOfFiscalYear	20000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due Within One Year Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueWithinOneYearOfBalanceSheetDate	94000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From One To Two Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromOneToTwoYearsOfBalanceSheetDate	80000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Two To Three Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromTwoToThreeYearsOfBalanceSheetDate	80000000	USD
CY2021Q3	us-gaap	Federal Home Loan Bank Advances Maturities Summary Due From Three To Four Years Of Balance Sheet Date FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate	50000000	USD
CY2021Q3	mbwm	Federal Home Loan Bank Advance Maturity After Year Four FederalHomeLoanBankAdvanceMaturityAfterYearFour	70000000	USD
CY2021Q3	mbwm	Reserve Or Liability Balance For Financial Instruments With Off Balance Sheet Risk ReserveOrLiabilityBalanceForFinancialInstrumentsWithOffBalanceSheetRisk	0	USD
CY2021Q3	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1573219000	USD
CY2020Q4	us-gaap	Fair Value Disclosure Offbalance Sheet Risks Amount Liability FairValueDisclosureOffbalanceSheetRisksAmountLiability	1430195000	USD
CY2021Q3	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	49100000	USD
CY2020Q4	us-gaap	Mortgages Held For Sale Fair Value Disclosure MortgagesHeldForSaleFairValueDisclosure	24000000.0	USD
	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
CY2021Q3	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	46000000.0	USD
CY2020Q4	mbwm	Trust Preferred Securities Included In Tier One Capital TrustPreferredSecuritiesIncludedInTierOneCapital	45500000	USD
CY2021Q3	mbwm	Capital Conservation Buffer CapitalConservationBuffer	0.025	pure
CY2021Q3	mbwm	Common Equity Tier1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets CommonEquityTier1RiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.070	pure
CY2021Q3	us-gaap	Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.085	pure
CY2021Q3	us-gaap	Capital Required For Capital Adequacy To Risk Weighted Assets CapitalRequiredForCapitalAdequacyToRiskWeightedAssets	0.105	pure
CY2021Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.29
CY2021Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.29
CY2021Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.30
CY2021Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000.0	USD
CY2019Q2	us-gaap	Stock Repurchase Program Authorized Amount1 StockRepurchaseProgramAuthorizedAmount1	20000000.0	USD
	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	636000
	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	19800000	USD
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	31.14
CY2021Q3	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	8400000	USD

Files In Submission

Name	View Source	Status
0001437749-21-025404-index-headers.html	Edgar Link	pending
0001437749-21-025404-index.html	Edgar Link	pending
0001437749-21-025404.txt	Edgar Link	pending
0001437749-21-025404-xbrl.zip	Edgar Link	pending
ex_298141.htm	Edgar Link	pending
ex_298142.htm	Edgar Link	pending
ex_298143.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
mbwm-20210930.xsd	Edgar Link	pending
mbwm-20210930_cal.xml	Edgar Link	unprocessable
mbwm-20210930_def.xml	Edgar Link	unprocessable
mbwm-20210930_lab.xml	Edgar Link	unprocessable
mbwm-20210930_pre.xml	Edgar Link	unprocessable
mbwm20210930_10q.htm	Edgar Link	pending
mbwm20210930_10q_htm.xml	Edgar Link	completed
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$MBWM
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2021 Q4 Form 10-Q Financial Statement

#000143774921025404 Filed on November 05, 2021

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$MBWM Mercantile Bank Corp Stock $mbwm

2021 Q4 Form 10-Q Financial Statement

#000143774921025404 Filed on November 05, 2021

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$MBWM
Mercantile Bank Corp Stock $mbwm